/*
* Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2016, 2019, SAP SE. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "asm/codeBuffer.hpp"
#include "asm/macroAssembler.inline.hpp"
#include "compiler/disassembler.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetAssembler.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "interpreter/interpreter.hpp"
#include "gc/shared/cardTableBarrierSet.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/accessDecorators.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/klass.inline.hpp"
#include "opto/compile.hpp"
#include "opto/intrinsicnode.hpp"
#include "opto/matcher.hpp"
#include "prims/methodHandles.hpp"
#include "registerSaver_s390.hpp"
#include "runtime/biasedLocking.hpp"
#include "runtime/icache.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/objectMonitor.hpp"
#include "runtime/os.hpp"
#include "runtime/safepoint.hpp"
#include "runtime/safepointMechanism.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/stubRoutines.hpp"
#include "utilities/events.hpp"
#include "utilities/macros.hpp"
#include <ucontext.h>
#define BLOCK_COMMENT(str) block_comment(str)
#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
// Move 32-bit register if destination and source are different.
void MacroAssembler::lr_if_needed(Register rd, Register rs) {
if (rs != rd) { z_lr(rd, rs); }
}
// Move register if destination and source are different.
void MacroAssembler::lgr_if_needed(Register rd, Register rs) {
if (rs != rd) { z_lgr(rd, rs); }
}
// Zero-extend 32-bit register into 64-bit register if destination and source are different.
void MacroAssembler::llgfr_if_needed(Register rd, Register rs) {
if (rs != rd) { z_llgfr(rd, rs); }
}
// Move float register if destination and source are different.
void MacroAssembler::ldr_if_needed(FloatRegister rd, FloatRegister rs) {
if (rs != rd) { z_ldr(rd, rs); }
}
// Move integer register if destination and source are different.
// It is assumed that shorter-than-int types are already
// appropriately sign-extended.
void MacroAssembler::move_reg_if_needed(Register dst, BasicType dst_type, Register src,
BasicType src_type) {
assert((dst_type != T_FLOAT) && (dst_type != T_DOUBLE), "use move_freg for float types");
assert((src_type != T_FLOAT) && (src_type != T_DOUBLE), "use move_freg for float types");
if (dst_type == src_type) {
lgr_if_needed(dst, src); // Just move all 64 bits.
return;
}
switch (dst_type) {
// Do not support these types for now.
// case T_BOOLEAN:
case T_BYTE: // signed byte
switch (src_type) {
case T_INT:
z_lgbr(dst, src);
break;
default:
ShouldNotReachHere();
}
return;
case T_CHAR:
case T_SHORT:
switch (src_type) {
case T_INT:
if (dst_type == T_CHAR) {
z_llghr(dst, src);
} else {
z_lghr(dst, src);
}
break;
default:
ShouldNotReachHere();
}
return;
case T_INT:
switch (src_type) {
case T_BOOLEAN:
case T_BYTE:
case T_CHAR:
case T_SHORT:
case T_INT:
case T_LONG:
case T_OBJECT:
case T_ARRAY:
case T_VOID:
case T_ADDRESS:
lr_if_needed(dst, src);
// llgfr_if_needed(dst, src); // zero-extend (in case we need to find a bug).
return;
default:
assert(false, "non-integer src type");
return;
}
case T_LONG:
switch (src_type) {
case T_BOOLEAN:
case T_BYTE:
case T_CHAR:
case T_SHORT:
case T_INT:
z_lgfr(dst, src); // sign extension
return;
case T_LONG:
case T_OBJECT:
case T_ARRAY:
case T_VOID:
case T_ADDRESS:
lgr_if_needed(dst, src);
return;
default:
assert(false, "non-integer src type");
return;
}
return;
case T_OBJECT:
case T_ARRAY:
case T_VOID:
case T_ADDRESS:
switch (src_type) {
// These types don't make sense to be converted to pointers:
// case T_BOOLEAN:
// case T_BYTE:
// case T_CHAR:
// case T_SHORT:
case T_INT:
z_llgfr(dst, src); // zero extension
return;
case T_LONG:
case T_OBJECT:
case T_ARRAY:
case T_VOID:
case T_ADDRESS:
lgr_if_needed(dst, src);
return;
default:
assert(false, "non-integer src type");
return;
}
return;
default:
assert(false, "non-integer dst type");
return;
}
}
// Move float register if destination and source are different.
void MacroAssembler::move_freg_if_needed(FloatRegister dst, BasicType dst_type,
FloatRegister src, BasicType src_type) {
assert((dst_type == T_FLOAT) || (dst_type == T_DOUBLE), "use move_reg for int types");
assert((src_type == T_FLOAT) || (src_type == T_DOUBLE), "use move_reg for int types");
if (dst_type == src_type) {
ldr_if_needed(dst, src); // Just move all 64 bits.
} else {
switch (dst_type) {
case T_FLOAT:
assert(src_type == T_DOUBLE, "invalid float type combination");
z_ledbr(dst, src);
return;
case T_DOUBLE:
assert(src_type == T_FLOAT, "invalid float type combination");
z_ldebr(dst, src);
return;
default:
assert(false, "non-float dst type");
return;
}
}
}
// Optimized emitter for reg to mem operations.
// Uses modern instructions if running on modern hardware, classic instructions
// otherwise. Prefers (usually shorter) classic instructions if applicable.
// Data register (reg) cannot be used as work register.
//
// Don't rely on register locking, instead pass a scratch register (Z_R0 by default).
// CAUTION! Passing registers >= Z_R2 may produce bad results on old CPUs!
void MacroAssembler::freg2mem_opt(FloatRegister reg,
int64_t disp,
Register index,
Register base,
void (MacroAssembler::*modern) (FloatRegister, int64_t, Register, Register),
void (MacroAssembler::*classic)(FloatRegister, int64_t, Register, Register),
Register scratch) {
index = (index == noreg) ? Z_R0 : index;
if (Displacement::is_shortDisp(disp)) {
(this->*classic)(reg, disp, index, base);
} else {
if (Displacement::is_validDisp(disp)) {
(this->*modern)(reg, disp, index, base);
} else {
if (scratch != Z_R0 && scratch != Z_R1) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
if (scratch != Z_R0) { // scratch == Z_R1
if ((scratch == index) || (index == base)) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
add2reg(scratch, disp, base);
(this->*classic)(reg, 0, index, scratch);
if (base == scratch) {
add2reg(base, -disp); // Restore base.
}
}
} else { // scratch == Z_R0
z_lgr(scratch, base);
add2reg(base, disp);
(this->*classic)(reg, 0, index, base);
z_lgr(base, scratch); // Restore base.
}
}
}
}
}
void MacroAssembler::freg2mem_opt(FloatRegister reg, const Address &a, bool is_double) {
if (is_double) {
freg2mem_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_FFUN(z_stdy), CLASSIC_FFUN(z_std));
} else {
freg2mem_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_FFUN(z_stey), CLASSIC_FFUN(z_ste));
}
}
// Optimized emitter for mem to reg operations.
// Uses modern instructions if running on modern hardware, classic instructions
// otherwise. Prefers (usually shorter) classic instructions if applicable.
// data register (reg) cannot be used as work register.
//
// Don't rely on register locking, instead pass a scratch register (Z_R0 by default).
// CAUTION! Passing registers >= Z_R2 may produce bad results on old CPUs!
void MacroAssembler::mem2freg_opt(FloatRegister reg,
int64_t disp,
Register index,
Register base,
void (MacroAssembler::*modern) (FloatRegister, int64_t, Register, Register),
void (MacroAssembler::*classic)(FloatRegister, int64_t, Register, Register),
Register scratch) {
index = (index == noreg) ? Z_R0 : index;
if (Displacement::is_shortDisp(disp)) {
(this->*classic)(reg, disp, index, base);
} else {
if (Displacement::is_validDisp(disp)) {
(this->*modern)(reg, disp, index, base);
} else {
if (scratch != Z_R0 && scratch != Z_R1) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
if (scratch != Z_R0) { // scratch == Z_R1
if ((scratch == index) || (index == base)) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
add2reg(scratch, disp, base);
(this->*classic)(reg, 0, index, scratch);
if (base == scratch) {
add2reg(base, -disp); // Restore base.
}
}
} else { // scratch == Z_R0
z_lgr(scratch, base);
add2reg(base, disp);
(this->*classic)(reg, 0, index, base);
z_lgr(base, scratch); // Restore base.
}
}
}
}
}
void MacroAssembler::mem2freg_opt(FloatRegister reg, const Address &a, bool is_double) {
if (is_double) {
mem2freg_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_FFUN(z_ldy), CLASSIC_FFUN(z_ld));
} else {
mem2freg_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_FFUN(z_ley), CLASSIC_FFUN(z_le));
}
}
// Optimized emitter for reg to mem operations.
// Uses modern instructions if running on modern hardware, classic instructions
// otherwise. Prefers (usually shorter) classic instructions if applicable.
// Data register (reg) cannot be used as work register.
//
// Don't rely on register locking, instead pass a scratch register
// (Z_R0 by default)
// CAUTION! passing registers >= Z_R2 may produce bad results on old CPUs!
void MacroAssembler::reg2mem_opt(Register reg,
int64_t disp,
Register index,
Register base,
void (MacroAssembler::*modern) (Register, int64_t, Register, Register),
void (MacroAssembler::*classic)(Register, int64_t, Register, Register),
Register scratch) {
index = (index == noreg) ? Z_R0 : index;
if (Displacement::is_shortDisp(disp)) {
(this->*classic)(reg, disp, index, base);
} else {
if (Displacement::is_validDisp(disp)) {
(this->*modern)(reg, disp, index, base);
} else {
if (scratch != Z_R0 && scratch != Z_R1) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
if (scratch != Z_R0) { // scratch == Z_R1
if ((scratch == index) || (index == base)) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
add2reg(scratch, disp, base);
(this->*classic)(reg, 0, index, scratch);
if (base == scratch) {
add2reg(base, -disp); // Restore base.
}
}
} else { // scratch == Z_R0
if ((scratch == reg) || (scratch == base) || (reg == base)) {
(this->*modern)(reg, disp, index, base); // Will fail with disp out of range.
} else {
z_lgr(scratch, base);
add2reg(base, disp);
(this->*classic)(reg, 0, index, base);
z_lgr(base, scratch); // Restore base.
}
}
}
}
}
}
int MacroAssembler::reg2mem_opt(Register reg, const Address &a, bool is_double) {
int store_offset = offset();
if (is_double) {
reg2mem_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_IFUN(z_stg), CLASSIC_IFUN(z_stg));
} else {
reg2mem_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_IFUN(z_sty), CLASSIC_IFUN(z_st));
}
return store_offset;
}
// Optimized emitter for mem to reg operations.
// Uses modern instructions if running on modern hardware, classic instructions
// otherwise. Prefers (usually shorter) classic instructions if applicable.
// Data register (reg) will be used as work register where possible.
void MacroAssembler::mem2reg_opt(Register reg,
int64_t disp,
Register index,
Register base,
void (MacroAssembler::*modern) (Register, int64_t, Register, Register),
void (MacroAssembler::*classic)(Register, int64_t, Register, Register)) {
index = (index == noreg) ? Z_R0 : index;
if (Displacement::is_shortDisp(disp)) {
(this->*classic)(reg, disp, index, base);
} else {
if (Displacement::is_validDisp(disp)) {
(this->*modern)(reg, disp, index, base);
} else {
if ((reg == index) && (reg == base)) {
z_sllg(reg, reg, 1);
add2reg(reg, disp);
(this->*classic)(reg, 0, noreg, reg);
} else if ((reg == index) && (reg != Z_R0)) {
add2reg(reg, disp);
(this->*classic)(reg, 0, reg, base);
} else if (reg == base) {
add2reg(reg, disp);
(this->*classic)(reg, 0, index, reg);
} else if (reg != Z_R0) {
add2reg(reg, disp, base);
(this->*classic)(reg, 0, index, reg);
} else { // reg == Z_R0 && reg != base here
add2reg(base, disp);
(this->*classic)(reg, 0, index, base);
add2reg(base, -disp);
}
}
}
}
void MacroAssembler::mem2reg_opt(Register reg, const Address &a, bool is_double) {
if (is_double) {
z_lg(reg, a);
} else {
mem2reg_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_IFUN(z_ly), CLASSIC_IFUN(z_l));
}
}
void MacroAssembler::mem2reg_signed_opt(Register reg, const Address &a) {
mem2reg_opt(reg, a.disp20(), a.indexOrR0(), a.baseOrR0(), MODERN_IFUN(z_lgf), CLASSIC_IFUN(z_lgf));
}
void MacroAssembler::and_imm(Register r, long mask,
Register tmp /* = Z_R0 */,
bool wide /* = false */) {
assert(wide || Immediate::is_simm32(mask), "mask value too large");
if (!wide) {
z_nilf(r, mask);
return;
}
assert(r != tmp, " need a different temporary register !");
load_const_optimized(tmp, mask);
z_ngr(r, tmp);
}
// Calculate the 1's complement.
// Note: The condition code is neither preserved nor correctly set by this code!!!
// Note: (wide == false) does not protect the high order half of the target register
// from alteration. It only serves as optimization hint for 32-bit results.
void MacroAssembler::not_(Register r1, Register r2, bool wide) {
if ((r2 == noreg) || (r2 == r1)) { // Calc 1's complement in place.
z_xilf(r1, -1);
if (wide) {
z_xihf(r1, -1);
}
} else { // Distinct src and dst registers.
load_const_optimized(r1, -1);
z_xgr(r1, r2);
}
}
unsigned long MacroAssembler::create_mask(int lBitPos, int rBitPos) {
assert(lBitPos >= 0, "zero is leftmost bit position");
assert(rBitPos <= 63, "63 is rightmost bit position");
assert(lBitPos <= rBitPos, "inverted selection interval");
return (lBitPos == 0 ? (unsigned long)(-1L) : ((1UL<<(63-lBitPos+1))-1)) & (~((1UL<<(63-rBitPos))-1));
}
// Helper function for the "Rotate_then_<logicalOP>" emitters.
// Rotate src, then mask register contents such that only bits in range survive.
// For oneBits == false, all bits not in range are set to 0. Useful for deleting all bits outside range.
// For oneBits == true, all bits not in range are set to 1. Useful for preserving all bits outside range.
// The caller must ensure that the selected range only contains bits with defined value.
void MacroAssembler::rotate_then_mask(Register dst, Register src, int lBitPos, int rBitPos,
int nRotate, bool src32bit, bool dst32bit, bool oneBits) {
assert(!(dst32bit && lBitPos < 32), "selection interval out of range for int destination");
bool sll4rll = (nRotate >= 0) && (nRotate <= (63-rBitPos)); // Substitute SLL(G) for RLL(G).
bool srl4rll = (nRotate < 0) && (-nRotate <= lBitPos); // Substitute SRL(G) for RLL(G).
// Pre-determine which parts of dst will be zero after shift/rotate.
bool llZero = sll4rll && (nRotate >= 16);
bool lhZero = (sll4rll && (nRotate >= 32)) || (srl4rll && (nRotate <= -48));
bool lfZero = llZero && lhZero;
bool hlZero = (sll4rll && (nRotate >= 48)) || (srl4rll && (nRotate <= -32));
bool hhZero = (srl4rll && (nRotate <= -16));
bool hfZero = hlZero && hhZero;
// rotate then mask src operand.
// if oneBits == true, all bits outside selected range are 1s.
// if oneBits == false, all bits outside selected range are 0s.
if (src32bit) { // There might be garbage in the upper 32 bits which will get masked away.
if (dst32bit) {
z_rll(dst, src, nRotate); // Copy and rotate, upper half of reg remains undisturbed.
} else {
if (sll4rll) { z_sllg(dst, src, nRotate); }
else if (srl4rll) { z_srlg(dst, src, -nRotate); }
else { z_rllg(dst, src, nRotate); }
}
} else {
if (sll4rll) { z_sllg(dst, src, nRotate); }
else if (srl4rll) { z_srlg(dst, src, -nRotate); }
else { z_rllg(dst, src, nRotate); }
}
unsigned long range_mask = create_mask(lBitPos, rBitPos);
unsigned int range_mask_h = (unsigned int)(range_mask >> 32);
unsigned int range_mask_l = (unsigned int)range_mask;
unsigned short range_mask_hh = (unsigned short)(range_mask >> 48);
unsigned short range_mask_hl = (unsigned short)(range_mask >> 32);
unsigned short range_mask_lh = (unsigned short)(range_mask >> 16);
unsigned short range_mask_ll = (unsigned short)range_mask;
// Works for z9 and newer H/W.
if (oneBits) {
if ((~range_mask_l) != 0) { z_oilf(dst, ~range_mask_l); } // All bits outside range become 1s.
if (((~range_mask_h) != 0) && !dst32bit) { z_oihf(dst, ~range_mask_h); }
} else {
// All bits outside range become 0s
if (((~range_mask_l) != 0) && !lfZero) {
z_nilf(dst, range_mask_l);
}
if (((~range_mask_h) != 0) && !dst32bit && !hfZero) {
z_nihf(dst, range_mask_h);
}
}
}
// Rotate src, then insert selected range from rotated src into dst.
// Clear dst before, if requested.
void MacroAssembler::rotate_then_insert(Register dst, Register src, int lBitPos, int rBitPos,
int nRotate, bool clear_dst) {
// This version does not depend on src being zero-extended int2long.
nRotate &= 0x003f; // For risbg, pretend it's an unsigned value.
z_risbg(dst, src, lBitPos, rBitPos, nRotate, clear_dst); // Rotate, then insert selected, clear the rest.
}
// Rotate src, then and selected range from rotated src into dst.
// Set condition code only if so requested. Otherwise it is unpredictable.
// See performance note in macroAssembler_s390.hpp for important information.
void MacroAssembler::rotate_then_and(Register dst, Register src, int lBitPos, int rBitPos,
int nRotate, bool test_only) {
guarantee(!test_only, "Emitter not fit for test_only instruction variant.");
// This version does not depend on src being zero-extended int2long.
nRotate &= 0x003f; // For risbg, pretend it's an unsigned value.
z_rxsbg(dst, src, lBitPos, rBitPos, nRotate, test_only); // Rotate, then xor selected.
}
// Rotate src, then or selected range from rotated src into dst.
// Set condition code only if so requested. Otherwise it is unpredictable.
// See performance note in macroAssembler_s390.hpp for important information.
void MacroAssembler::rotate_then_or(Register dst, Register src, int lBitPos, int rBitPos,
int nRotate, bool test_only) {
guarantee(!test_only, "Emitter not fit for test_only instruction variant.");
// This version does not depend on src being zero-extended int2long.
nRotate &= 0x003f; // For risbg, pretend it's an unsigned value.
z_rosbg(dst, src, lBitPos, rBitPos, nRotate, test_only); // Rotate, then xor selected.
}
// Rotate src, then xor selected range from rotated src into dst.
// Set condition code only if so requested. Otherwise it is unpredictable.
// See performance note in macroAssembler_s390.hpp for important information.
void MacroAssembler::rotate_then_xor(Register dst, Register src, int lBitPos, int rBitPos,
int nRotate, bool test_only) {
guarantee(!test_only, "Emitter not fit for test_only instruction variant.");
// This version does not depend on src being zero-extended int2long.
nRotate &= 0x003f; // For risbg, pretend it's an unsigned value.
z_rxsbg(dst, src, lBitPos, rBitPos, nRotate, test_only); // Rotate, then xor selected.
}
void MacroAssembler::add64(Register r1, RegisterOrConstant inc) {
if (inc.is_register()) {
z_agr(r1, inc.as_register());
} else { // constant
intptr_t imm = inc.as_constant();
add2reg(r1, imm);
}
}
// Helper function to multiply the 64bit contents of a register by a 16bit constant.
// The optimization tries to avoid the mghi instruction, since it uses the FPU for
// calculation and is thus rather slow.
//
// There is no handling for special cases, e.g. cval==0 or cval==1.
//
// Returns len of generated code block.
unsigned int MacroAssembler::mul_reg64_const16(Register rval, Register work, int cval) {
int block_start = offset();
bool sign_flip = cval < 0;
cval = sign_flip ? -cval : cval;
BLOCK_COMMENT("Reg64*Con16 {");
int bit1 = cval & -cval;
if (bit1 == cval) {
z_sllg(rval, rval, exact_log2(bit1));
if (sign_flip) { z_lcgr(rval, rval); }
} else {
int bit2 = (cval-bit1) & -(cval-bit1);
if ((bit1+bit2) == cval) {
z_sllg(work, rval, exact_log2(bit1));
z_sllg(rval, rval, exact_log2(bit2));
z_agr(rval, work);
if (sign_flip) { z_lcgr(rval, rval); }
} else {
if (sign_flip) { z_mghi(rval, -cval); }
else { z_mghi(rval, cval); }
}
}
BLOCK_COMMENT("} Reg64*Con16");
int block_end = offset();
return block_end - block_start;
}
// Generic operation r1 := r2 + imm.
//
// Should produce the best code for each supported CPU version.
// r2 == noreg yields r1 := r1 + imm
// imm == 0 emits either no instruction or r1 := r2 !
// NOTES: 1) Don't use this function where fixed sized
// instruction sequences are required!!!
// 2) Don't use this function if condition code
// setting is required!
// 3) Despite being declared as int64_t, the parameter imm
// must be a simm_32 value (= signed 32-bit integer).
void MacroAssembler::add2reg(Register r1, int64_t imm, Register r2) {
assert(Immediate::is_simm32(imm), "probably an implicit conversion went wrong");
if (r2 == noreg) { r2 = r1; }
// Handle special case imm == 0.
if (imm == 0) {
lgr_if_needed(r1, r2);
// Nothing else to do.
return;
}
if (!PreferLAoverADD || (r2 == Z_R0)) {
bool distinctOpnds = VM_Version::has_DistinctOpnds();
// Can we encode imm in 16 bits signed?
if (Immediate::is_simm16(imm)) {
if (r1 == r2) {
z_aghi(r1, imm);
return;
}
if (distinctOpnds) {
z_aghik(r1, r2, imm);
return;
}
z_lgr(r1, r2);
z_aghi(r1, imm);
return;
}
} else {
// Can we encode imm in 12 bits unsigned?
if (Displacement::is_shortDisp(imm)) {
z_la(r1, imm, r2);
return;
}
// Can we encode imm in 20 bits signed?
if (Displacement::is_validDisp(imm)) {
// Always use LAY instruction, so we don't need the tmp register.
z_lay(r1, imm, r2);
return;
}
}
// Can handle it (all possible values) with long immediates.
lgr_if_needed(r1, r2);
z_agfi(r1, imm);
}
// Generic operation r := b + x + d
//
// Addition of several operands with address generation semantics - sort of:
// - no restriction on the registers. Any register will do for any operand.
// - x == noreg: operand will be disregarded.
// - b == noreg: will use (contents of) result reg as operand (r := r + d).
// - x == Z_R0: just disregard
// - b == Z_R0: use as operand. This is not address generation semantics!!!
//
// The same restrictions as on add2reg() are valid!!!
void MacroAssembler::add2reg_with_index(Register r, int64_t d, Register x, Register b) {
assert(Immediate::is_simm32(d), "probably an implicit conversion went wrong");
if (x == noreg) { x = Z_R0; }
if (b == noreg) { b = r; }
// Handle special case x == R0.
if (x == Z_R0) {
// Can simply add the immediate value to the base register.
add2reg(r, d, b);
return;
}
if (!PreferLAoverADD || (b == Z_R0)) {
bool distinctOpnds = VM_Version::has_DistinctOpnds();
// Handle special case d == 0.
if (d == 0) {
if (b == x) { z_sllg(r, b, 1); return; }
if (r == x) { z_agr(r, b); return; }
if (r == b) { z_agr(r, x); return; }
if (distinctOpnds) { z_agrk(r, x, b); return; }
z_lgr(r, b);
z_agr(r, x);
} else {
if (x == b) { z_sllg(r, x, 1); }
else if (r == x) { z_agr(r, b); }
else if (r == b) { z_agr(r, x); }
else if (distinctOpnds) { z_agrk(r, x, b); }
else {
z_lgr(r, b);
z_agr(r, x);
}
add2reg(r, d);
}
} else {
// Can we encode imm in 12 bits unsigned?
if (Displacement::is_shortDisp(d)) {
z_la(r, d, x, b);
return;
}
// Can we encode imm in 20 bits signed?
if (Displacement::is_validDisp(d)) {
z_lay(r, d, x, b);
return;
}
z_la(r, 0, x, b);
add2reg(r, d);
}
}
// Generic emitter (32bit) for direct memory increment.
// For optimal code, do not specify Z_R0 as temp register.
void MacroAssembler::add2mem_32(const Address &a, int64_t imm, Register tmp) {
if (VM_Version::has_MemWithImmALUOps() && Immediate::is_simm8(imm)) {
z_asi(a, imm);
} else {
z_lgf(tmp, a);
add2reg(tmp, imm);
z_st(tmp, a);
}
}
void MacroAssembler::add2mem_64(const Address &a, int64_t imm, Register tmp) {
if (VM_Version::has_MemWithImmALUOps() && Immediate::is_simm8(imm)) {
z_agsi(a, imm);
} else {
z_lg(tmp, a);
add2reg(tmp, imm);
z_stg(tmp, a);
}
}
void MacroAssembler::load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed) {
switch (size_in_bytes) {
case 8: z_lg(dst, src); break;
case 4: is_signed ? z_lgf(dst, src) : z_llgf(dst, src); break;
case 2: is_signed ? z_lgh(dst, src) : z_llgh(dst, src); break;
case 1: is_signed ? z_lgb(dst, src) : z_llgc(dst, src); break;
default: ShouldNotReachHere();
}
}
void MacroAssembler::store_sized_value(Register src, Address dst, size_t size_in_bytes) {
switch (size_in_bytes) {
case 8: z_stg(src, dst); break;
case 4: z_st(src, dst); break;
case 2: z_sth(src, dst); break;
case 1: z_stc(src, dst); break;
default: ShouldNotReachHere();
}
}
// Split a si20 offset (20bit, signed) into an ui12 offset (12bit, unsigned) and
// a high-order summand in register tmp.
//
// return value: < 0: No split required, si20 actually has property uimm12.
// >= 0: Split performed. Use return value as uimm12 displacement and
// tmp as index register.
int MacroAssembler::split_largeoffset(int64_t si20_offset, Register tmp, bool fixed_codelen, bool accumulate) {
assert(Immediate::is_simm20(si20_offset), "sanity");
int lg_off = (int)si20_offset & 0x0fff; // Punch out low-order 12 bits, always positive.
int ll_off = (int)si20_offset & ~0x0fff; // Force low-order 12 bits to zero.
assert((Displacement::is_shortDisp(si20_offset) && (ll_off == 0)) ||
!Displacement::is_shortDisp(si20_offset), "unexpected offset values");
assert((lg_off+ll_off) == si20_offset, "offset splitup error");
Register work = accumulate? Z_R0 : tmp;
if (fixed_codelen) { // Len of code = 10 = 4 + 6.
z_lghi(work, ll_off>>12); // Implicit sign extension.
z_slag(work, work, 12);
} else { // Len of code = 0..10.
if (ll_off == 0) { return -1; }
// ll_off has 8 significant bits (at most) plus sign.
if ((ll_off & 0x0000f000) == 0) { // Non-zero bits only in upper halfbyte.
z_llilh(work, ll_off >> 16);
if (ll_off < 0) { // Sign-extension required.
z_lgfr(work, work);
}
} else {
if ((ll_off & 0x000f0000) == 0) { // Non-zero bits only in lower halfbyte.
z_llill(work, ll_off);
} else { // Non-zero bits in both halfbytes.
z_lghi(work, ll_off>>12); // Implicit sign extension.
z_slag(work, work, 12);
}
}
}
if (accumulate) { z_algr(tmp, work); } // len of code += 4
return lg_off;
}
void MacroAssembler::load_float_largeoffset(FloatRegister t, int64_t si20, Register a, Register tmp) {
if (Displacement::is_validDisp(si20)) {
z_ley(t, si20, a);
} else {
// Fixed_codelen = true is a simple way to ensure that the size of load_float_largeoffset
// does not depend on si20 (scratch buffer emit size == code buffer emit size for constant
// pool loads).
bool accumulate = true;
bool fixed_codelen = true;
Register work;
if (fixed_codelen) {
z_lgr(tmp, a); // Lgr_if_needed not applicable due to fixed_codelen.
} else {
accumulate = (a == tmp);
}
work = tmp;
int disp12 = split_largeoffset(si20, work, fixed_codelen, accumulate);
if (disp12 < 0) {
z_le(t, si20, work);
} else {
if (accumulate) {
z_le(t, disp12, work);
} else {
z_le(t, disp12, work, a);
}
}
}
}
void MacroAssembler::load_double_largeoffset(FloatRegister t, int64_t si20, Register a, Register tmp) {
if (Displacement::is_validDisp(si20)) {
z_ldy(t, si20, a);
} else {
// Fixed_codelen = true is a simple way to ensure that the size of load_double_largeoffset
// does not depend on si20 (scratch buffer emit size == code buffer emit size for constant
// pool loads).
bool accumulate = true;
bool fixed_codelen = true;
Register work;
if (fixed_codelen) {
z_lgr(tmp, a); // Lgr_if_needed not applicable due to fixed_codelen.
} else {
accumulate = (a == tmp);
}
work = tmp;
int disp12 = split_largeoffset(si20, work, fixed_codelen, accumulate);
if (disp12 < 0) {
z_ld(t, si20, work);
} else {
if (accumulate) {
z_ld(t, disp12, work);
} else {
z_ld(t, disp12, work, a);
}
}
}
}
// PCrelative TOC access.
// Returns distance (in bytes) from current position to start of consts section.
// Returns 0 (zero) if no consts section exists or if it has size zero.
long MacroAssembler::toc_distance() {
CodeSection* cs = code()->consts();
return (long)((cs != NULL) ? cs->start()-pc() : 0);
}
// Implementation on x86/sparc assumes that constant and instruction section are
// adjacent, but this doesn't hold. Two special situations may occur, that we must
// be able to handle:
// 1. const section may be located apart from the inst section.
// 2. const section may be empty
// In both cases, we use the const section's start address to compute the "TOC",
// this seems to occur only temporarily; in the final step we always seem to end up
// with the pc-relatice variant.
//
// PC-relative offset could be +/-2**32 -> use long for disp
// Furthermore: makes no sense to have special code for
// adjacent const and inst sections.
void MacroAssembler::load_toc(Register Rtoc) {
// Simply use distance from start of const section (should be patched in the end).
long disp = toc_distance();
RelocationHolder rspec = internal_word_Relocation::spec(pc() + disp);
relocate(rspec);
z_larl(Rtoc, RelAddr::pcrel_off32(disp)); // Offset is in halfwords.
}
// PCrelative TOC access.
// Load from anywhere pcrelative (with relocation of load instr)
void MacroAssembler::load_long_pcrelative(Register Rdst, address dataLocation) {
address pc = this->pc();
ptrdiff_t total_distance = dataLocation - pc;
RelocationHolder rspec = internal_word_Relocation::spec(dataLocation);
assert((total_distance & 0x01L) == 0, "halfword alignment is mandatory");
assert(total_distance != 0, "sanity");
// Some extra safety net.
if (!RelAddr::is_in_range_of_RelAddr32(total_distance)) {
guarantee(RelAddr::is_in_range_of_RelAddr32(total_distance), "load_long_pcrelative can't handle distance " INTPTR_FORMAT, total_distance);
}
(this)->relocate(rspec, relocInfo::pcrel_addr_format);
z_lgrl(Rdst, RelAddr::pcrel_off32(total_distance));
}
// PCrelative TOC access.
// Load from anywhere pcrelative (with relocation of load instr)
// loaded addr has to be relocated when added to constant pool.
void MacroAssembler::load_addr_pcrelative(Register Rdst, address addrLocation) {
address pc = this->pc();
ptrdiff_t total_distance = addrLocation - pc;
RelocationHolder rspec = internal_word_Relocation::spec(addrLocation);
assert((total_distance & 0x01L) == 0, "halfword alignment is mandatory");
// Some extra safety net.
if (!RelAddr::is_in_range_of_RelAddr32(total_distance)) {
guarantee(RelAddr::is_in_range_of_RelAddr32(total_distance), "load_long_pcrelative can't handle distance " INTPTR_FORMAT, total_distance);
}
(this)->relocate(rspec, relocInfo::pcrel_addr_format);
z_lgrl(Rdst, RelAddr::pcrel_off32(total_distance));
}
// Generic operation: load a value from memory and test.
// CondCode indicates the sign (<0, ==0, >0) of the loaded value.
void MacroAssembler::load_and_test_byte(Register dst, const Address &a) {
z_lb(dst, a);
z_ltr(dst, dst);
}
void MacroAssembler::load_and_test_short(Register dst, const Address &a) {
int64_t disp = a.disp20();
if (Displacement::is_shortDisp(disp)) {
z_lh(dst, a);
} else if (Displacement::is_longDisp(disp)) {
z_lhy(dst, a);
} else {
guarantee(false, "displacement out of range");
}
z_ltr(dst, dst);
}
void MacroAssembler::load_and_test_int(Register dst, const Address &a) {
z_lt(dst, a);
}
void MacroAssembler::load_and_test_int2long(Register dst, const Address &a) {
z_ltgf(dst, a);
}
void MacroAssembler::load_and_test_long(Register dst, const Address &a) {
z_ltg(dst, a);
}
// Test a bit in memory.
void MacroAssembler::testbit(const Address &a, unsigned int bit) {
assert(a.index() == noreg, "no index reg allowed in testbit");
if (bit <= 7) {
z_tm(a.disp() + 3, a.base(), 1 << bit);
} else if (bit <= 15) {
z_tm(a.disp() + 2, a.base(), 1 << (bit - 8));
} else if (bit <= 23) {
z_tm(a.disp() + 1, a.base(), 1 << (bit - 16));
} else if (bit <= 31) {
z_tm(a.disp() + 0, a.base(), 1 << (bit - 24));
} else {
ShouldNotReachHere();
}
}
// Test a bit in a register. Result is reflected in CC.
void MacroAssembler::testbit(Register r, unsigned int bitPos) {
if (bitPos < 16) {
z_tmll(r, 1U<<bitPos);
} else if (bitPos < 32) {
z_tmlh(r, 1U<<(bitPos-16));
} else if (bitPos < 48) {
z_tmhl(r, 1U<<(bitPos-32));
} else if (bitPos < 64) {
z_tmhh(r, 1U<<(bitPos-48));
} else {
ShouldNotReachHere();
}
}
void MacroAssembler::prefetch_read(Address a) {
z_pfd(1, a.disp20(), a.indexOrR0(), a.base());
}
void MacroAssembler::prefetch_update(Address a) {
z_pfd(2, a.disp20(), a.indexOrR0(), a.base());
}
// Clear a register, i.e. load const zero into reg.
// Return len (in bytes) of generated instruction(s).
// whole_reg: Clear 64 bits if true, 32 bits otherwise.
// set_cc: Use instruction that sets the condition code, if true.
int MacroAssembler::clear_reg(Register r, bool whole_reg, bool set_cc) {
unsigned int start_off = offset();
if (whole_reg) {
set_cc ? z_xgr(r, r) : z_laz(r, 0, Z_R0);
} else { // Only 32bit register.
set_cc ? z_xr(r, r) : z_lhi(r, 0);
}
return offset() - start_off;
}
#ifdef ASSERT
int MacroAssembler::preset_reg(Register r, unsigned long pattern, int pattern_len) {
switch (pattern_len) {
case 1:
pattern = (pattern & 0x000000ff) | ((pattern & 0x000000ff)<<8);
case 2:
pattern = (pattern & 0x0000ffff) | ((pattern & 0x0000ffff)<<16);
case 4:
pattern = (pattern & 0xffffffffL) | ((pattern & 0xffffffffL)<<32);
case 8:
return load_const_optimized_rtn_len(r, pattern, true);
break;
default:
guarantee(false, "preset_reg: bad len");
}
return 0;
}
#endif
// addr: Address descriptor of memory to clear index register will not be used !
// size: Number of bytes to clear.
// !!! DO NOT USE THEM FOR ATOMIC MEMORY CLEARING !!!
// !!! Use store_const() instead !!!
void MacroAssembler::clear_mem(const Address& addr, unsigned size) {
guarantee(size <= 256, "MacroAssembler::clear_mem: size too large");
if (size == 1) {
z_mvi(addr, 0);
return;
}
switch (size) {
case 2: z_mvhhi(addr, 0);
return;
case 4: z_mvhi(addr, 0);
return;
case 8: z_mvghi(addr, 0);
return;
default: ; // Fallthru to xc.
}
z_xc(addr, size, addr);
}
void MacroAssembler::align(int modulus) {
while (offset() % modulus != 0) z_nop();
}
// Special version for non-relocateable code if required alignment
// is larger than CodeEntryAlignment.
void MacroAssembler::align_address(int modulus) {
while ((uintptr_t)pc() % modulus != 0) z_nop();
}
Address MacroAssembler::argument_address(RegisterOrConstant arg_slot,
Register temp_reg,
int64_t extra_slot_offset) {
// On Z, we can have index and disp in an Address. So don't call argument_offset,
// which issues an unnecessary add instruction.
int stackElementSize = Interpreter::stackElementSize;
int64_t offset = extra_slot_offset * stackElementSize;
const Register argbase = Z_esp;
if (arg_slot.is_constant()) {
offset += arg_slot.as_constant() * stackElementSize;
return Address(argbase, offset);
}
// else
assert(temp_reg != noreg, "must specify");
assert(temp_reg != Z_ARG1, "base and index are conflicting");
z_sllg(temp_reg, arg_slot.as_register(), exact_log2(stackElementSize)); // tempreg = arg_slot << 3
return Address(argbase, temp_reg, offset);
}
//===================================================================
//=== START C O N S T A N T S I N C O D E S T R E A M ===
//===================================================================
//=== P A T CH A B L E C O N S T A N T S ===
//===================================================================
//---------------------------------------------------
// Load (patchable) constant into register
//---------------------------------------------------
// Load absolute address (and try to optimize).
// Note: This method is usable only for position-fixed code,
// referring to a position-fixed target location.
// If not so, relocations and patching must be used.
void MacroAssembler::load_absolute_address(Register d, address addr) {
assert(addr != NULL, "should not happen");
BLOCK_COMMENT("load_absolute_address:");
if (addr == NULL) {
z_larl(d, pc()); // Dummy emit for size calc.
return;
}
if (RelAddr::is_in_range_of_RelAddr32(addr, pc())) {
z_larl(d, addr);
return;
}
load_const_optimized(d, (long)addr);
}
// Load a 64bit constant.
// Patchable code sequence, but not atomically patchable.
// Make sure to keep code size constant -> no value-dependent optimizations.
// Do not kill condition code.
void MacroAssembler::load_const(Register t, long x) {
// Note: Right shift is only cleanly defined for unsigned types
// or for signed types with nonnegative values.
Assembler::z_iihf(t, (long)((unsigned long)x >> 32));
Assembler::z_iilf(t, (long)((unsigned long)x & 0xffffffffUL));
}
// Load a 32bit constant into a 64bit register, sign-extend or zero-extend.
// Patchable code sequence, but not atomically patchable.
// Make sure to keep code size constant -> no value-dependent optimizations.
// Do not kill condition code.
void MacroAssembler::load_const_32to64(Register t, int64_t x, bool sign_extend) {
if (sign_extend) { Assembler::z_lgfi(t, x); }
else { Assembler::z_llilf(t, x); }
}
// Load narrow oop constant, no decompression.
void MacroAssembler::load_narrow_oop(Register t, narrowOop a) {
assert(UseCompressedOops, "must be on to call this method");
load_const_32to64(t, a, false /*sign_extend*/);
}
// Load narrow klass constant, compression required.
void MacroAssembler::load_narrow_klass(Register t, Klass* k) {
assert(UseCompressedClassPointers, "must be on to call this method");
narrowKlass encoded_k = CompressedKlassPointers::encode(k);
load_const_32to64(t, encoded_k, false /*sign_extend*/);
}
//------------------------------------------------------
// Compare (patchable) constant with register.
//------------------------------------------------------
// Compare narrow oop in reg with narrow oop constant, no decompression.
void MacroAssembler::compare_immediate_narrow_oop(Register oop1, narrowOop oop2) {
assert(UseCompressedOops, "must be on to call this method");
Assembler::z_clfi(oop1, oop2);
}
// Compare narrow oop in reg with narrow oop constant, no decompression.
void MacroAssembler::compare_immediate_narrow_klass(Register klass1, Klass* klass2) {
assert(UseCompressedClassPointers, "must be on to call this method");
narrowKlass encoded_k = CompressedKlassPointers::encode(klass2);
Assembler::z_clfi(klass1, encoded_k);
}
//----------------------------------------------------------
// Check which kind of load_constant we have here.
//----------------------------------------------------------
// Detection of CPU version dependent load_const sequence.
// The detection is valid only for code sequences generated by load_const,
// not load_const_optimized.
bool MacroAssembler::is_load_const(address a) {
unsigned long inst1, inst2;
unsigned int len1, len2;
len1 = get_instruction(a, &inst1);
len2 = get_instruction(a + len1, &inst2);
return is_z_iihf(inst1) && is_z_iilf(inst2);
}
// Detection of CPU version dependent load_const_32to64 sequence.
// Mostly used for narrow oops and narrow Klass pointers.
// The detection is valid only for code sequences generated by load_const_32to64.
bool MacroAssembler::is_load_const_32to64(address pos) {
unsigned long inst1, inst2;
unsigned int len1;
len1 = get_instruction(pos, &inst1);
return is_z_llilf(inst1);
}
// Detection of compare_immediate_narrow sequence.
// The detection is valid only for code sequences generated by compare_immediate_narrow_oop.
bool MacroAssembler::is_compare_immediate32(address pos) {
return is_equal(pos, CLFI_ZOPC, RIL_MASK);
}
// Detection of compare_immediate_narrow sequence.
// The detection is valid only for code sequences generated by compare_immediate_narrow_oop.
bool MacroAssembler::is_compare_immediate_narrow_oop(address pos) {
return is_compare_immediate32(pos);
}
// Detection of compare_immediate_narrow sequence.
// The detection is valid only for code sequences generated by compare_immediate_narrow_klass.
bool MacroAssembler::is_compare_immediate_narrow_klass(address pos) {
return is_compare_immediate32(pos);
}
//-----------------------------------
// patch the load_constant
//-----------------------------------
// CPU-version dependend patching of load_const.
void MacroAssembler::patch_const(address a, long x) {
assert(is_load_const(a), "not a load of a constant");
// Note: Right shift is only cleanly defined for unsigned types
// or for signed types with nonnegative values.
set_imm32((address)a, (long)((unsigned long)x >> 32));
set_imm32((address)(a + 6), (long)((unsigned long)x & 0xffffffffUL));
}
// Patching the value of CPU version dependent load_const_32to64 sequence.
// The passed ptr MUST be in compressed format!
int MacroAssembler::patch_load_const_32to64(address pos, int64_t np) {
assert(is_load_const_32to64(pos), "not a load of a narrow ptr (oop or klass)");
set_imm32(pos, np);
return 6;
}
// Patching the value of CPU version dependent compare_immediate_narrow sequence.
// The passed ptr MUST be in compressed format!
int MacroAssembler::patch_compare_immediate_32(address pos, int64_t np) {
assert(is_compare_immediate32(pos), "not a compressed ptr compare");
set_imm32(pos, np);
return 6;
}
// Patching the immediate value of CPU version dependent load_narrow_oop sequence.
// The passed ptr must NOT be in compressed format!
int MacroAssembler::patch_load_narrow_oop(address pos, oop o) {
assert(UseCompressedOops, "Can only patch compressed oops");
narrowOop no = CompressedOops::encode(o);
return patch_load_const_32to64(pos, no);
}
// Patching the immediate value of CPU version dependent load_narrow_klass sequence.
// The passed ptr must NOT be in compressed format!
int MacroAssembler::patch_load_narrow_klass(address pos, Klass* k) {
assert(UseCompressedClassPointers, "Can only patch compressed klass pointers");
narrowKlass nk = CompressedKlassPointers::encode(k);
return patch_load_const_32to64(pos, nk);
}
// Patching the immediate value of CPU version dependent compare_immediate_narrow_oop sequence.
// The passed ptr must NOT be in compressed format!
int MacroAssembler::patch_compare_immediate_narrow_oop(address pos, oop o) {
assert(UseCompressedOops, "Can only patch compressed oops");
narrowOop no = CompressedOops::encode(o);
return patch_compare_immediate_32(pos, no);
}
// Patching the immediate value of CPU version dependent compare_immediate_narrow_klass sequence.
// The passed ptr must NOT be in compressed format!
int MacroAssembler::patch_compare_immediate_narrow_klass(address pos, Klass* k) {
assert(UseCompressedClassPointers, "Can only patch compressed klass pointers");
narrowKlass nk = CompressedKlassPointers::encode(k);
return patch_compare_immediate_32(pos, nk);
}
//------------------------------------------------------------------------
// Extract the constant from a load_constant instruction stream.
//------------------------------------------------------------------------
// Get constant from a load_const sequence.
long MacroAssembler::get_const(address a) {
assert(is_load_const(a), "not a load of a constant");
unsigned long x;
x = (((unsigned long) (get_imm32(a,0) & 0xffffffff)) << 32);
x |= (((unsigned long) (get_imm32(a,1) & 0xffffffff)));
return (long) x;
}
//--------------------------------------
// Store a constant in memory.
//--------------------------------------
// General emitter to move a constant to memory.
// The store is atomic.
// o Address must be given in RS format (no index register)
// o Displacement should be 12bit unsigned for efficiency. 20bit signed also supported.
// o Constant can be 1, 2, 4, or 8 bytes, signed or unsigned.
// o Memory slot can be 1, 2, 4, or 8 bytes, signed or unsigned.
// o Memory slot must be at least as wide as constant, will assert otherwise.
// o Signed constants will sign-extend, unsigned constants will zero-extend to slot width.
int MacroAssembler::store_const(const Address &dest, long imm,
unsigned int lm, unsigned int lc,
Register scratch) {
int64_t disp = dest.disp();
Register base = dest.base();
assert(!dest.has_index(), "not supported");
assert((lm==1)||(lm==2)||(lm==4)||(lm==8), "memory length not supported");
assert((lc==1)||(lc==2)||(lc==4)||(lc==8), "constant length not supported");
assert(lm>=lc, "memory slot too small");
assert(lc==8 || Immediate::is_simm(imm, lc*8), "const out of range");
assert(Displacement::is_validDisp(disp), "displacement out of range");
bool is_shortDisp = Displacement::is_shortDisp(disp);
int store_offset = -1;
// For target len == 1 it's easy.
if (lm == 1) {
store_offset = offset();
if (is_shortDisp) {
z_mvi(disp, base, imm);
return store_offset;
} else {
z_mviy(disp, base, imm);
return store_offset;
}
}
// All the "good stuff" takes an unsigned displacement.
if (is_shortDisp) {
// NOTE: Cannot use clear_mem for imm==0, because it is not atomic.
store_offset = offset();
switch (lm) {
case 2: // Lc == 1 handled correctly here, even for unsigned. Instruction does no widening.
z_mvhhi(disp, base, imm);
return store_offset;
case 4:
if (Immediate::is_simm16(imm)) {
z_mvhi(disp, base, imm);
return store_offset;
}
break;
case 8:
if (Immediate::is_simm16(imm)) {
z_mvghi(disp, base, imm);
return store_offset;
}
break;
default:
ShouldNotReachHere();
break;
}
}
// Can't optimize, so load value and store it.
guarantee(scratch != noreg, " need a scratch register here !");
if (imm != 0) {
load_const_optimized(scratch, imm); // Preserves CC anyway.
} else {
// Leave CC alone!!
(void) clear_reg(scratch, true, false); // Indicate unused result.
}
store_offset = offset();
if (is_shortDisp) {
switch (lm) {
case 2:
z_sth(scratch, disp, Z_R0, base);
return store_offset;
case 4:
z_st(scratch, disp, Z_R0, base);
return store_offset;
case 8:
z_stg(scratch, disp, Z_R0, base);
return store_offset;
default:
ShouldNotReachHere();
break;
}
} else {
switch (lm) {
case 2:
z_sthy(scratch, disp, Z_R0, base);
return store_offset;
case 4:
z_sty(scratch, disp, Z_R0, base);
return store_offset;
case 8:
z_stg(scratch, disp, Z_R0, base);
return store_offset;
default:
ShouldNotReachHere();
break;
}
}
return -1; // should not reach here
}
//===================================================================
//=== N O T P A T CH A B L E C O N S T A N T S ===
//===================================================================
// Load constant x into register t with a fast instrcution sequence
// depending on the bits in x. Preserves CC under all circumstances.
int MacroAssembler::load_const_optimized_rtn_len(Register t, long x, bool emit) {
if (x == 0) {
int len;
if (emit) {
len = clear_reg(t, true, false);
} else {
len = 4;
}
return len;
}
if (Immediate::is_simm16(x)) {
if (emit) { z_lghi(t, x); }
return 4;
}
// 64 bit value: | part1 | part2 | part3 | part4 |
// At least one part is not zero!
// Note: Right shift is only cleanly defined for unsigned types
// or for signed types with nonnegative values.
int part1 = (int)((unsigned long)x >> 48) & 0x0000ffff;
int part2 = (int)((unsigned long)x >> 32) & 0x0000ffff;
int part3 = (int)((unsigned long)x >> 16) & 0x0000ffff;
int part4 = (int)x & 0x0000ffff;
int part12 = (int)((unsigned long)x >> 32);
int part34 = (int)x;
// Lower word only (unsigned).
if (part12 == 0) {
if (part3 == 0) {
if (emit) z_llill(t, part4);
return 4;
}
if (part4 == 0) {
if (emit) z_llilh(t, part3);
return 4;
}
if (emit) z_llilf(t, part34);
return 6;
}
// Upper word only.
if (part34 == 0) {
if (part1 == 0) {
if (emit) z_llihl(t, part2);
return 4;
}
if (part2 == 0) {
if (emit) z_llihh(t, part1);
return 4;
}
if (emit) z_llihf(t, part12);
return 6;
}
// Lower word only (signed).
if ((part1 == 0x0000ffff) && (part2 == 0x0000ffff) && ((part3 & 0x00008000) != 0)) {
if (emit) z_lgfi(t, part34);
return 6;
}
int len = 0;
if ((part1 == 0) || (part2 == 0)) {
if (part1 == 0) {
if (emit) z_llihl(t, part2);
len += 4;
} else {
if (emit) z_llihh(t, part1);
len += 4;
}
} else {
if (emit) z_llihf(t, part12);
len += 6;
}
if ((part3 == 0) || (part4 == 0)) {
if (part3 == 0) {
if (emit) z_iill(t, part4);
len += 4;
} else {
if (emit) z_iilh(t, part3);
len += 4;
}
} else {
if (emit) z_iilf(t, part34);
len += 6;
}
return len;
}
//=====================================================================
//=== H I G H E R L E V E L B R A N C H E M I T T E R S ===
//=====================================================================
// Note: In the worst case, one of the scratch registers is destroyed!!!
void MacroAssembler::compare32_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& lbl) {
// Right operand is constant.
if (x2.is_constant()) {
jlong value = x2.as_constant();
compare_and_branch_optimized(r1, value, cond, lbl, /*len64=*/false, /*has_sign=*/true);
return;
}
// Right operand is in register.
compare_and_branch_optimized(r1, x2.as_register(), cond, lbl, /*len64=*/false, /*has_sign=*/true);
}
// Note: In the worst case, one of the scratch registers is destroyed!!!
void MacroAssembler::compareU32_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& lbl) {
// Right operand is constant.
if (x2.is_constant()) {
jlong value = x2.as_constant();
compare_and_branch_optimized(r1, value, cond, lbl, /*len64=*/false, /*has_sign=*/false);
return;
}
// Right operand is in register.
compare_and_branch_optimized(r1, x2.as_register(), cond, lbl, /*len64=*/false, /*has_sign=*/false);
}
// Note: In the worst case, one of the scratch registers is destroyed!!!
void MacroAssembler::compare64_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& lbl) {
// Right operand is constant.
if (x2.is_constant()) {
jlong value = x2.as_constant();
compare_and_branch_optimized(r1, value, cond, lbl, /*len64=*/true, /*has_sign=*/true);
return;
}
// Right operand is in register.
compare_and_branch_optimized(r1, x2.as_register(), cond, lbl, /*len64=*/true, /*has_sign=*/true);
}
void MacroAssembler::compareU64_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& lbl) {
// Right operand is constant.
if (x2.is_constant()) {
jlong value = x2.as_constant();
compare_and_branch_optimized(r1, value, cond, lbl, /*len64=*/true, /*has_sign=*/false);
return;
}
// Right operand is in register.
compare_and_branch_optimized(r1, x2.as_register(), cond, lbl, /*len64=*/true, /*has_sign=*/false);
}
// Generate an optimal branch to the branch target.
// Optimal means that a relative branch (brc or brcl) is used if the
// branch distance is short enough. Loading the target address into a
// register and branching via reg is used as fallback only.
//
// Used registers:
// Z_R1 - work reg. Holds branch target address.
// Used in fallback case only.
//
// This version of branch_optimized is good for cases where the target address is known
// and constant, i.e. is never changed (no relocation, no patching).
void MacroAssembler::branch_optimized(Assembler::branch_condition cond, address branch_addr) {
address branch_origin = pc();
if (RelAddr::is_in_range_of_RelAddr16(branch_addr, branch_origin)) {
z_brc(cond, branch_addr);
} else if (RelAddr::is_in_range_of_RelAddr32(branch_addr, branch_origin)) {
z_brcl(cond, branch_addr);
} else {
load_const_optimized(Z_R1, branch_addr); // CC must not get killed by load_const_optimized.
z_bcr(cond, Z_R1);
}
}
// This version of branch_optimized is good for cases where the target address
// is potentially not yet known at the time the code is emitted.
//
// One very common case is a branch to an unbound label which is handled here.
// The caller might know (or hope) that the branch distance is short enough
// to be encoded in a 16bit relative address. In this case he will pass a
// NearLabel branch_target.
// Care must be taken with unbound labels. Each call to target(label) creates
// an entry in the patch queue for that label to patch all references of the label
// once it gets bound. Those recorded patch locations must be patchable. Otherwise,
// an assertion fires at patch time.
void MacroAssembler::branch_optimized(Assembler::branch_condition cond, Label& branch_target) {
if (branch_target.is_bound()) {
address branch_addr = target(branch_target);
branch_optimized(cond, branch_addr);
} else if (branch_target.is_near()) {
z_brc(cond, branch_target); // Caller assures that the target will be in range for z_brc.
} else {
z_brcl(cond, branch_target); // Let's hope target is in range. Otherwise, we will abort at patch time.
}
}
// Generate an optimal compare and branch to the branch target.
// Optimal means that a relative branch (clgrj, brc or brcl) is used if the
// branch distance is short enough. Loading the target address into a
// register and branching via reg is used as fallback only.
//
// Input:
// r1 - left compare operand
// r2 - right compare operand
void MacroAssembler::compare_and_branch_optimized(Register r1,
Register r2,
Assembler::branch_condition cond,
address branch_addr,
bool len64,
bool has_sign) {
unsigned int casenum = (len64?2:0)+(has_sign?0:1);
address branch_origin = pc();
if (VM_Version::has_CompareBranch() && RelAddr::is_in_range_of_RelAddr16(branch_addr, branch_origin)) {
switch (casenum) {
case 0: z_crj( r1, r2, cond, branch_addr); break;
case 1: z_clrj (r1, r2, cond, branch_addr); break;
case 2: z_cgrj(r1, r2, cond, branch_addr); break;
case 3: z_clgrj(r1, r2, cond, branch_addr); break;
default: ShouldNotReachHere(); break;
}
} else {
switch (casenum) {
case 0: z_cr( r1, r2); break;
case 1: z_clr(r1, r2); break;
case 2: z_cgr(r1, r2); break;
case 3: z_clgr(r1, r2); break;
default: ShouldNotReachHere(); break;
}
branch_optimized(cond, branch_addr);
}
}
// Generate an optimal compare and branch to the branch target.
// Optimal means that a relative branch (clgij, brc or brcl) is used if the
// branch distance is short enough. Loading the target address into a
// register and branching via reg is used as fallback only.
//
// Input:
// r1 - left compare operand (in register)
// x2 - right compare operand (immediate)
void MacroAssembler::compare_and_branch_optimized(Register r1,
jlong x2,
Assembler::branch_condition cond,
Label& branch_target,
bool len64,
bool has_sign) {
address branch_origin = pc();
bool x2_imm8 = (has_sign && Immediate::is_simm8(x2)) || (!has_sign && Immediate::is_uimm8(x2));
bool is_RelAddr16 = branch_target.is_near() ||
(branch_target.is_bound() &&
RelAddr::is_in_range_of_RelAddr16(target(branch_target), branch_origin));
unsigned int casenum = (len64?2:0)+(has_sign?0:1);
if (VM_Version::has_CompareBranch() && is_RelAddr16 && x2_imm8) {
switch (casenum) {
case 0: z_cij( r1, x2, cond, branch_target); break;
case 1: z_clij(r1, x2, cond, branch_target); break;
case 2: z_cgij(r1, x2, cond, branch_target); break;
case 3: z_clgij(r1, x2, cond, branch_target); break;
default: ShouldNotReachHere(); break;
}
return;
}
if (x2 == 0) {
switch (casenum) {
case 0: z_ltr(r1, r1); break;
case 1: z_ltr(r1, r1); break; // Caution: unsigned test only provides zero/notZero indication!
case 2: z_ltgr(r1, r1); break;
case 3: z_ltgr(r1, r1); break; // Caution: unsigned test only provides zero/notZero indication!
default: ShouldNotReachHere(); break;
}
} else {
if ((has_sign && Immediate::is_simm16(x2)) || (!has_sign && Immediate::is_uimm(x2, 15))) {
switch (casenum) {
case 0: z_chi(r1, x2); break;
case 1: z_chi(r1, x2); break; // positive immediate < 2**15
case 2: z_cghi(r1, x2); break;
case 3: z_cghi(r1, x2); break; // positive immediate < 2**15
default: break;
}
} else if ( (has_sign && Immediate::is_simm32(x2)) || (!has_sign && Immediate::is_uimm32(x2)) ) {
switch (casenum) {
case 0: z_cfi( r1, x2); break;
case 1: z_clfi(r1, x2); break;
case 2: z_cgfi(r1, x2); break;
case 3: z_clgfi(r1, x2); break;
default: ShouldNotReachHere(); break;
}
} else {
// No instruction with immediate operand possible, so load into register.
Register scratch = (r1 != Z_R0) ? Z_R0 : Z_R1;
load_const_optimized(scratch, x2);
switch (casenum) {
case 0: z_cr( r1, scratch); break;
case 1: z_clr(r1, scratch); break;
case 2: z_cgr(r1, scratch); break;
case 3: z_clgr(r1, scratch); break;
default: ShouldNotReachHere(); break;
}
}
}
branch_optimized(cond, branch_target);
}
// Generate an optimal compare and branch to the branch target.
// Optimal means that a relative branch (clgrj, brc or brcl) is used if the
// branch distance is short enough. Loading the target address into a
// register and branching via reg is used as fallback only.
//
// Input:
// r1 - left compare operand
// r2 - right compare operand
void MacroAssembler::compare_and_branch_optimized(Register r1,
Register r2,
Assembler::branch_condition cond,
Label& branch_target,
bool len64,
bool has_sign) {
unsigned int casenum = (len64 ? 2 : 0) + (has_sign ? 0 : 1);
if (branch_target.is_bound()) {
address branch_addr = target(branch_target);
compare_and_branch_optimized(r1, r2, cond, branch_addr, len64, has_sign);
} else {
if (VM_Version::has_CompareBranch() && branch_target.is_near()) {
switch (casenum) {
case 0: z_crj( r1, r2, cond, branch_target); break;
case 1: z_clrj( r1, r2, cond, branch_target); break;
case 2: z_cgrj( r1, r2, cond, branch_target); break;
case 3: z_clgrj(r1, r2, cond, branch_target); break;
default: ShouldNotReachHere(); break;
}
} else {
switch (casenum) {
case 0: z_cr( r1, r2); break;
case 1: z_clr(r1, r2); break;
case 2: z_cgr(r1, r2); break;
case 3: z_clgr(r1, r2); break;
default: ShouldNotReachHere(); break;
}
branch_optimized(cond, branch_target);
}
}
}
//===========================================================================
//=== END H I G H E R L E V E L B R A N C H E M I T T E R S ===
//===========================================================================
AddressLiteral MacroAssembler::allocate_metadata_address(Metadata* obj) {
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
int index = oop_recorder()->allocate_metadata_index(obj);
RelocationHolder rspec = metadata_Relocation::spec(index);
return AddressLiteral((address)obj, rspec);
}
AddressLiteral MacroAssembler::constant_metadata_address(Metadata* obj) {
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
int index = oop_recorder()->find_index(obj);
RelocationHolder rspec = metadata_Relocation::spec(index);
return AddressLiteral((address)obj, rspec);
}
AddressLiteral MacroAssembler::allocate_oop_address(jobject obj) {
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
int oop_index = oop_recorder()->allocate_oop_index(obj);
return AddressLiteral(address(obj), oop_Relocation::spec(oop_index));
}
AddressLiteral MacroAssembler::constant_oop_address(jobject obj) {
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
int oop_index = oop_recorder()->find_index(obj);
return AddressLiteral(address(obj), oop_Relocation::spec(oop_index));
}
// NOTE: destroys r
void MacroAssembler::c2bool(Register r, Register t) {
z_lcr(t, r); // t = -r
z_or(r, t); // r = -r OR r
z_srl(r, 31); // Yields 0 if r was 0, 1 otherwise.
}
RegisterOrConstant MacroAssembler::delayed_value_impl(intptr_t* delayed_value_addr,
Register tmp,
int offset) {
intptr_t value = *delayed_value_addr;
if (value != 0) {
return RegisterOrConstant(value + offset);
}
BLOCK_COMMENT("delayed_value {");
// Load indirectly to solve generation ordering problem.
load_absolute_address(tmp, (address) delayed_value_addr); // tmp = a;
z_lg(tmp, 0, tmp); // tmp = *tmp;
#ifdef ASSERT
NearLabel L;
compare64_and_branch(tmp, (intptr_t)0L, Assembler::bcondNotEqual, L);
z_illtrap();
bind(L);
#endif
if (offset != 0) {
z_agfi(tmp, offset); // tmp = tmp + offset;
}
BLOCK_COMMENT("} delayed_value");
return RegisterOrConstant(tmp);
}
// Patch instruction `inst' at offset `inst_pos' to refer to `dest_pos'
// and return the resulting instruction.
// Dest_pos and inst_pos are 32 bit only. These parms can only designate
// relative positions.
// Use correct argument types. Do not pre-calculate distance.
unsigned long MacroAssembler::patched_branch(address dest_pos, unsigned long inst, address inst_pos) {
int c = 0;
unsigned long patched_inst = 0;
if (is_call_pcrelative_short(inst) ||
is_branch_pcrelative_short(inst) ||
is_branchoncount_pcrelative_short(inst) ||
is_branchonindex32_pcrelative_short(inst)) {
c = 1;
int m = fmask(15, 0); // simm16(-1, 16, 32);
int v = simm16(RelAddr::pcrel_off16(dest_pos, inst_pos), 16, 32);
patched_inst = (inst & ~m) | v;
} else if (is_compareandbranch_pcrelative_short(inst)) {
c = 2;
long m = fmask(31, 16); // simm16(-1, 16, 48);
long v = simm16(RelAddr::pcrel_off16(dest_pos, inst_pos), 16, 48);
patched_inst = (inst & ~m) | v;
} else if (is_branchonindex64_pcrelative_short(inst)) {
c = 3;
long m = fmask(31, 16); // simm16(-1, 16, 48);
long v = simm16(RelAddr::pcrel_off16(dest_pos, inst_pos), 16, 48);
patched_inst = (inst & ~m) | v;
} else if (is_call_pcrelative_long(inst) || is_branch_pcrelative_long(inst)) {
c = 4;
long m = fmask(31, 0); // simm32(-1, 16, 48);
long v = simm32(RelAddr::pcrel_off32(dest_pos, inst_pos), 16, 48);
patched_inst = (inst & ~m) | v;
} else if (is_pcrelative_long(inst)) { // These are the non-branch pc-relative instructions.
c = 5;
long m = fmask(31, 0); // simm32(-1, 16, 48);
long v = simm32(RelAddr::pcrel_off32(dest_pos, inst_pos), 16, 48);
patched_inst = (inst & ~m) | v;
} else {
print_dbg_msg(tty, inst, "not a relative branch", 0);
dump_code_range(tty, inst_pos, 32, "not a pcrelative branch");
ShouldNotReachHere();
}
long new_off = get_pcrel_offset(patched_inst);
if (new_off != (dest_pos-inst_pos)) {
tty->print_cr("case %d: dest_pos = %p, inst_pos = %p, disp = %ld(%12.12lx)", c, dest_pos, inst_pos, new_off, new_off);
print_dbg_msg(tty, inst, "<- original instruction: branch patching error", 0);
print_dbg_msg(tty, patched_inst, "<- patched instruction: branch patching error", 0);
#ifdef LUCY_DBG
VM_Version::z_SIGSEGV();
#endif
ShouldNotReachHere();
}
return patched_inst;
}
// Only called when binding labels (share/vm/asm/assembler.cpp)
// Pass arguments as intended. Do not pre-calculate distance.
void MacroAssembler::pd_patch_instruction(address branch, address target, const char* file, int line) {
unsigned long stub_inst;
int inst_len = get_instruction(branch, &stub_inst);
set_instruction(branch, patched_branch(target, stub_inst, branch), inst_len);
}
// Extract relative address (aka offset).
// inv_simm16 works for 4-byte instructions only.
// compare and branch instructions are 6-byte and have a 16bit offset "in the middle".
long MacroAssembler::get_pcrel_offset(unsigned long inst) {
if (MacroAssembler::is_pcrelative_short(inst)) {
if (((inst&0xFFFFffff00000000UL) == 0) && ((inst&0x00000000FFFF0000UL) != 0)) {
return RelAddr::inv_pcrel_off16(inv_simm16(inst));
} else {
return RelAddr::inv_pcrel_off16(inv_simm16_48(inst));
}
}
if (MacroAssembler::is_pcrelative_long(inst)) {
return RelAddr::inv_pcrel_off32(inv_simm32(inst));
}
print_dbg_msg(tty, inst, "not a pcrelative instruction", 6);
#ifdef LUCY_DBG
VM_Version::z_SIGSEGV();
#else
ShouldNotReachHere();
#endif
return -1;
}
long MacroAssembler::get_pcrel_offset(address pc) {
unsigned long inst;
unsigned int len = get_instruction(pc, &inst);
#ifdef ASSERT
long offset;
if (MacroAssembler::is_pcrelative_short(inst) || MacroAssembler::is_pcrelative_long(inst)) {
offset = get_pcrel_offset(inst);
} else {
offset = -1;
}
if (offset == -1) {
dump_code_range(tty, pc, 32, "not a pcrelative instruction");
#ifdef LUCY_DBG
VM_Version::z_SIGSEGV();
#else
ShouldNotReachHere();
#endif
}
return offset;
#else
return get_pcrel_offset(inst);
#endif // ASSERT
}
// Get target address from pc-relative instructions.
address MacroAssembler::get_target_addr_pcrel(address pc) {
assert(is_pcrelative_long(pc), "not a pcrelative instruction");
return pc + get_pcrel_offset(pc);
}
// Patch pc relative load address.
void MacroAssembler::patch_target_addr_pcrel(address pc, address con) {
unsigned long inst;
// Offset is +/- 2**32 -> use long.
ptrdiff_t distance = con - pc;
get_instruction(pc, &inst);
if (is_pcrelative_short(inst)) {
*(short *)(pc+2) = RelAddr::pcrel_off16(con, pc); // Instructions are at least 2-byte aligned, no test required.
// Some extra safety net.
if (!RelAddr::is_in_range_of_RelAddr16(distance)) {
print_dbg_msg(tty, inst, "distance out of range (16bit)", 4);
dump_code_range(tty, pc, 32, "distance out of range (16bit)");
guarantee(RelAddr::is_in_range_of_RelAddr16(distance), "too far away (more than +/- 2**16");
}
return;
}
if (is_pcrelative_long(inst)) {
*(int *)(pc+2) = RelAddr::pcrel_off32(con, pc);
// Some Extra safety net.
if (!RelAddr::is_in_range_of_RelAddr32(distance)) {
print_dbg_msg(tty, inst, "distance out of range (32bit)", 6);
dump_code_range(tty, pc, 32, "distance out of range (32bit)");
guarantee(RelAddr::is_in_range_of_RelAddr32(distance), "too far away (more than +/- 2**32");
}
return;
}
guarantee(false, "not a pcrelative instruction to patch!");
}
// "Current PC" here means the address just behind the basr instruction.
address MacroAssembler::get_PC(Register result) {
z_basr(result, Z_R0); // Don't branch, just save next instruction address in result.
return pc();
}
// Get current PC + offset.
// Offset given in bytes, must be even!
// "Current PC" here means the address of the larl instruction plus the given offset.
address MacroAssembler::get_PC(Register result, int64_t offset) {
address here = pc();
z_larl(result, offset/2); // Save target instruction address in result.
return here + offset;
}
void MacroAssembler::instr_size(Register size, Register pc) {
// Extract 2 most significant bits of current instruction.
z_llgc(size, Address(pc));
z_srl(size, 6);
// Compute (x+3)&6 which translates 0->2, 1->4, 2->4, 3->6.
z_ahi(size, 3);
z_nill(size, 6);
}
// Resize_frame with SP(new) = SP(old) - [offset].
void MacroAssembler::resize_frame_sub(Register offset, Register fp, bool load_fp)
{
assert_different_registers(offset, fp, Z_SP);
if (load_fp) { z_lg(fp, _z_abi(callers_sp), Z_SP); }
z_sgr(Z_SP, offset);
z_stg(fp, _z_abi(callers_sp), Z_SP);
}
// Resize_frame with SP(new) = [newSP] + offset.
// This emitter is useful if we already have calculated a pointer
// into the to-be-allocated stack space, e.g. with special alignment properties,
// but need some additional space, e.g. for spilling.
// newSP is the pre-calculated pointer. It must not be modified.
// fp holds, or is filled with, the frame pointer.
// offset is the additional increment which is added to addr to form the new SP.
// Note: specify a negative value to reserve more space!
// load_fp == true only indicates that fp is not pre-filled with the frame pointer.
// It does not guarantee that fp contains the frame pointer at the end.
void MacroAssembler::resize_frame_abs_with_offset(Register newSP, Register fp, int offset, bool load_fp) {
assert_different_registers(newSP, fp, Z_SP);
if (load_fp) {
z_lg(fp, _z_abi(callers_sp), Z_SP);
}
add2reg(Z_SP, offset, newSP);
z_stg(fp, _z_abi(callers_sp), Z_SP);
}
// Resize_frame with SP(new) = [newSP].
// load_fp == true only indicates that fp is not pre-filled with the frame pointer.
// It does not guarantee that fp contains the frame pointer at the end.
void MacroAssembler::resize_frame_absolute(Register newSP, Register fp, bool load_fp) {
assert_different_registers(newSP, fp, Z_SP);
if (load_fp) {
z_lg(fp, _z_abi(callers_sp), Z_SP); // need to use load/store.
}
z_lgr(Z_SP, newSP);
if (newSP != Z_R0) { // make sure we generate correct code, no matter what register newSP uses.
z_stg(fp, _z_abi(callers_sp), newSP);
} else {
z_stg(fp, _z_abi(callers_sp), Z_SP);
}
}
// Resize_frame with SP(new) = SP(old) + offset.
void MacroAssembler::resize_frame(RegisterOrConstant offset, Register fp, bool load_fp) {
assert_different_registers(fp, Z_SP);
if (load_fp) {
z_lg(fp, _z_abi(callers_sp), Z_SP);
}
add64(Z_SP, offset);
z_stg(fp, _z_abi(callers_sp), Z_SP);
}
void MacroAssembler::push_frame(Register bytes, Register old_sp, bool copy_sp, bool bytes_with_inverted_sign) {
#ifdef ASSERT
assert_different_registers(bytes, old_sp, Z_SP);
if (!copy_sp) {
z_cgr(old_sp, Z_SP);
asm_assert_eq("[old_sp]!=[Z_SP]", 0x211);
}
#endif
if (copy_sp) { z_lgr(old_sp, Z_SP); }
if (bytes_with_inverted_sign) {
z_agr(Z_SP, bytes);
} else {
z_sgr(Z_SP, bytes); // Z_sgfr sufficient, but probably not faster.
}
z_stg(old_sp, _z_abi(callers_sp), Z_SP);
}
unsigned int MacroAssembler::push_frame(unsigned int bytes, Register scratch) {
long offset = Assembler::align(bytes, frame::alignment_in_bytes);
assert(offset > 0, "should push a frame with positive size, size = %ld.", offset);
assert(Displacement::is_validDisp(-offset), "frame size out of range, size = %ld", offset);
// We must not write outside the current stack bounds (given by Z_SP).
// Thus, we have to first update Z_SP and then store the previous SP as stack linkage.
// We rely on Z_R0 by default to be available as scratch.
z_lgr(scratch, Z_SP);
add2reg(Z_SP, -offset);
z_stg(scratch, _z_abi(callers_sp), Z_SP);
#ifdef ASSERT
// Just make sure nobody uses the value in the default scratch register.
// When another register is used, the caller might rely on it containing the frame pointer.
if (scratch == Z_R0) {
z_iihf(scratch, 0xbaadbabe);
z_iilf(scratch, 0xdeadbeef);
}
#endif
return offset;
}
// Push a frame of size `bytes' plus abi160 on top.
unsigned int MacroAssembler::push_frame_abi160(unsigned int bytes) {
BLOCK_COMMENT("push_frame_abi160 {");
unsigned int res = push_frame(bytes + frame::z_abi_160_size);
BLOCK_COMMENT("} push_frame_abi160");
return res;
}
// Pop current C frame.
void MacroAssembler::pop_frame() {
BLOCK_COMMENT("pop_frame:");
Assembler::z_lg(Z_SP, _z_abi(callers_sp), Z_SP);
}
// Pop current C frame and restore return PC register (Z_R14).
void MacroAssembler::pop_frame_restore_retPC(int frame_size_in_bytes) {
BLOCK_COMMENT("pop_frame_restore_retPC:");
int retPC_offset = _z_abi16(return_pc) + frame_size_in_bytes;
// If possible, pop frame by add instead of load (a penny saved is a penny got :-).
if (Displacement::is_validDisp(retPC_offset)) {
z_lg(Z_R14, retPC_offset, Z_SP);
add2reg(Z_SP, frame_size_in_bytes);
} else {
add2reg(Z_SP, frame_size_in_bytes);
restore_return_pc();
}
}
void MacroAssembler::call_VM_leaf_base(address entry_point, bool allow_relocation) {
if (allow_relocation) {
call_c(entry_point);
} else {
call_c_static(entry_point);
}
}
void MacroAssembler::call_VM_leaf_base(address entry_point) {
bool allow_relocation = true;
call_VM_leaf_base(entry_point, allow_relocation);
}
void MacroAssembler::call_VM_base(Register oop_result,
Register last_java_sp,
address entry_point,
bool allow_relocation,
bool check_exceptions) { // Defaults to true.
// Allow_relocation indicates, if true, that the generated code shall
// be fit for code relocation or referenced data relocation. In other
// words: all addresses must be considered variable. PC-relative addressing
// is not possible then.
// On the other hand, if (allow_relocation == false), addresses and offsets
// may be considered stable, enabling us to take advantage of some PC-relative
// addressing tweaks. These might improve performance and reduce code size.
// Determine last_java_sp register.
if (!last_java_sp->is_valid()) {
last_java_sp = Z_SP; // Load Z_SP as SP.
}
set_top_ijava_frame_at_SP_as_last_Java_frame(last_java_sp, Z_R1, allow_relocation);
// ARG1 must hold thread address.
z_lgr(Z_ARG1, Z_thread);
address return_pc = NULL;
if (allow_relocation) {
return_pc = call_c(entry_point);
} else {
return_pc = call_c_static(entry_point);
}
reset_last_Java_frame(allow_relocation);
// C++ interp handles this in the interpreter.
check_and_handle_popframe(Z_thread);
check_and_handle_earlyret(Z_thread);
// Check for pending exceptions.
if (check_exceptions) {
// Check for pending exceptions (java_thread is set upon return).
load_and_test_long(Z_R0_scratch, Address(Z_thread, Thread::pending_exception_offset()));
// This used to conditionally jump to forward_exception however it is
// possible if we relocate that the branch will not reach. So we must jump
// around so we can always reach.
Label ok;
z_bre(ok); // Bcondequal is the same as bcondZero.
call_stub(StubRoutines::forward_exception_entry());
bind(ok);
}
// Get oop result if there is one and reset the value in the thread.
if (oop_result->is_valid()) {
get_vm_result(oop_result);
}
_last_calls_return_pc = return_pc; // Wipe out other (error handling) calls.
}
void MacroAssembler::call_VM_base(Register oop_result,
Register last_java_sp,
address entry_point,
bool check_exceptions) { // Defaults to true.
bool allow_relocation = true;
call_VM_base(oop_result, last_java_sp, entry_point, allow_relocation, check_exceptions);
}
// VM calls without explicit last_java_sp.
void MacroAssembler::call_VM(Register oop_result, address entry_point, bool check_exceptions) {
// Call takes possible detour via InterpreterMacroAssembler.
call_VM_base(oop_result, noreg, entry_point, true, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, address entry_point, Register arg_1, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
call_VM(oop_result, entry_point, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, address entry_point, Register arg_1, Register arg_2, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
assert(arg_2 != Z_ARG2, "smashed argument");
lgr_if_needed(Z_ARG3, arg_2);
call_VM(oop_result, entry_point, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, address entry_point, Register arg_1, Register arg_2,
Register arg_3, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
assert(arg_2 != Z_ARG2, "smashed argument");
lgr_if_needed(Z_ARG3, arg_2);
assert(arg_3 != Z_ARG2 && arg_3 != Z_ARG3, "smashed argument");
lgr_if_needed(Z_ARG4, arg_3);
call_VM(oop_result, entry_point, check_exceptions);
}
// VM static calls without explicit last_java_sp.
void MacroAssembler::call_VM_static(Register oop_result, address entry_point, bool check_exceptions) {
// Call takes possible detour via InterpreterMacroAssembler.
call_VM_base(oop_result, noreg, entry_point, false, check_exceptions);
}
void MacroAssembler::call_VM_static(Register oop_result, address entry_point, Register arg_1, Register arg_2,
Register arg_3, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
assert(arg_2 != Z_ARG2, "smashed argument");
lgr_if_needed(Z_ARG3, arg_2);
assert(arg_3 != Z_ARG2 && arg_3 != Z_ARG3, "smashed argument");
lgr_if_needed(Z_ARG4, arg_3);
call_VM_static(oop_result, entry_point, check_exceptions);
}
// VM calls with explicit last_java_sp.
void MacroAssembler::call_VM(Register oop_result, Register last_java_sp, address entry_point, bool check_exceptions) {
// Call takes possible detour via InterpreterMacroAssembler.
call_VM_base(oop_result, last_java_sp, entry_point, true, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
call_VM(oop_result, last_java_sp, entry_point, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1,
Register arg_2, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
assert(arg_2 != Z_ARG2, "smashed argument");
lgr_if_needed(Z_ARG3, arg_2);
call_VM(oop_result, last_java_sp, entry_point, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1,
Register arg_2, Register arg_3, bool check_exceptions) {
// Z_ARG1 is reserved for the thread.
lgr_if_needed(Z_ARG2, arg_1);
assert(arg_2 != Z_ARG2, "smashed argument");
lgr_if_needed(Z_ARG3, arg_2);
assert(arg_3 != Z_ARG2 && arg_3 != Z_ARG3, "smashed argument");
lgr_if_needed(Z_ARG4, arg_3);
call_VM(oop_result, last_java_sp, entry_point, check_exceptions);
}
// VM leaf calls.
void MacroAssembler::call_VM_leaf(address entry_point) {
// Call takes possible detour via InterpreterMacroAssembler.
call_VM_leaf_base(entry_point, true);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_1) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
call_VM_leaf(entry_point);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_1, Register arg_2) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
assert(arg_2 != Z_ARG1, "smashed argument");
if (arg_2 != noreg) lgr_if_needed(Z_ARG2, arg_2);
call_VM_leaf(entry_point);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_1, Register arg_2, Register arg_3) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
assert(arg_2 != Z_ARG1, "smashed argument");
if (arg_2 != noreg) lgr_if_needed(Z_ARG2, arg_2);
assert(arg_3 != Z_ARG1 && arg_3 != Z_ARG2, "smashed argument");
if (arg_3 != noreg) lgr_if_needed(Z_ARG3, arg_3);
call_VM_leaf(entry_point);
}
// Static VM leaf calls.
// Really static VM leaf calls are never patched.
void MacroAssembler::call_VM_leaf_static(address entry_point) {
// Call takes possible detour via InterpreterMacroAssembler.
call_VM_leaf_base(entry_point, false);
}
void MacroAssembler::call_VM_leaf_static(address entry_point, Register arg_1) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
call_VM_leaf_static(entry_point);
}
void MacroAssembler::call_VM_leaf_static(address entry_point, Register arg_1, Register arg_2) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
assert(arg_2 != Z_ARG1, "smashed argument");
if (arg_2 != noreg) lgr_if_needed(Z_ARG2, arg_2);
call_VM_leaf_static(entry_point);
}
void MacroAssembler::call_VM_leaf_static(address entry_point, Register arg_1, Register arg_2, Register arg_3) {
if (arg_1 != noreg) lgr_if_needed(Z_ARG1, arg_1);
assert(arg_2 != Z_ARG1, "smashed argument");
if (arg_2 != noreg) lgr_if_needed(Z_ARG2, arg_2);
assert(arg_3 != Z_ARG1 && arg_3 != Z_ARG2, "smashed argument");
if (arg_3 != noreg) lgr_if_needed(Z_ARG3, arg_3);
call_VM_leaf_static(entry_point);
}
// Don't use detour via call_c(reg).
address MacroAssembler::call_c(address function_entry) {
load_const(Z_R1, function_entry);
return call(Z_R1);
}
// Variant for really static (non-relocatable) calls which are never patched.
address MacroAssembler::call_c_static(address function_entry) {
load_absolute_address(Z_R1, function_entry);
#if 0 // def ASSERT
// Verify that call site did not move.
load_const_optimized(Z_R0, function_entry);
z_cgr(Z_R1, Z_R0);
z_brc(bcondEqual, 3);
z_illtrap(0xba);
#endif
return call(Z_R1);
}
address MacroAssembler::call_c_opt(address function_entry) {
bool success = call_far_patchable(function_entry, -2 /* emit relocation + constant */);
_last_calls_return_pc = success ? pc() : NULL;
return _last_calls_return_pc;
}
// Identify a call_far_patchable instruction: LARL + LG + BASR
//
// nop ; optionally, if required for alignment
// lgrl rx,A(TOC entry) ; PC-relative access into constant pool
// basr Z_R14,rx ; end of this instruction must be aligned to a word boundary
//
// Code pattern will eventually get patched into variant2 (see below for detection code).
//
bool MacroAssembler::is_call_far_patchable_variant0_at(address instruction_addr) {
address iaddr = instruction_addr;
// Check for the actual load instruction.
if (!is_load_const_from_toc(iaddr)) { return false; }
iaddr += load_const_from_toc_size();
// Check for the call (BASR) instruction, finally.
assert(iaddr-instruction_addr+call_byregister_size() == call_far_patchable_size(), "size mismatch");
return is_call_byregister(iaddr);
}
// Identify a call_far_patchable instruction: BRASL
//
// Code pattern to suits atomic patching:
// nop ; Optionally, if required for alignment.
// nop ... ; Multiple filler nops to compensate for size difference (variant0 is longer).
// nop ; For code pattern detection: Prepend each BRASL with a nop.
// brasl Z_R14,<reladdr> ; End of code must be 4-byte aligned !
bool MacroAssembler::is_call_far_patchable_variant2_at(address instruction_addr) {
const address call_addr = (address)((intptr_t)instruction_addr + call_far_patchable_size() - call_far_pcrelative_size());
// Check for correct number of leading nops.
address iaddr;
for (iaddr = instruction_addr; iaddr < call_addr; iaddr += nop_size()) {
if (!is_z_nop(iaddr)) { return false; }
}
assert(iaddr == call_addr, "sanity");
// --> Check for call instruction.
if (is_call_far_pcrelative(call_addr)) {
assert(call_addr-instruction_addr+call_far_pcrelative_size() == call_far_patchable_size(), "size mismatch");
return true;
}
return false;
}
// Emit a NOT mt-safely patchable 64 bit absolute call.
// If toc_offset == -2, then the destination of the call (= target) is emitted
// to the constant pool and a runtime_call relocation is added
// to the code buffer.
// If toc_offset != -2, target must already be in the constant pool at
// _ctableStart+toc_offset (a caller can retrieve toc_offset
// from the runtime_call relocation).
// Special handling of emitting to scratch buffer when there is no constant pool.
// Slightly changed code pattern. We emit an additional nop if we would
// not end emitting at a word aligned address. This is to ensure
// an atomically patchable displacement in brasl instructions.
//
// A call_far_patchable comes in different flavors:
// - LARL(CP) / LG(CP) / BR (address in constant pool, access via CP register)
// - LGRL(CP) / BR (address in constant pool, pc-relative accesss)
// - BRASL (relative address of call target coded in instruction)
// All flavors occupy the same amount of space. Length differences are compensated
// by leading nops, such that the instruction sequence always ends at the same
// byte offset. This is required to keep the return offset constant.
// Furthermore, the return address (the end of the instruction sequence) is forced
// to be on a 4-byte boundary. This is required for atomic patching, should we ever
// need to patch the call target of the BRASL flavor.
// RETURN value: false, if no constant pool entry could be allocated, true otherwise.
bool MacroAssembler::call_far_patchable(address target, int64_t tocOffset) {
// Get current pc and ensure word alignment for end of instr sequence.
const address start_pc = pc();
const intptr_t start_off = offset();
assert(!call_far_patchable_requires_alignment_nop(start_pc), "call_far_patchable requires aligned address");
const ptrdiff_t dist = (ptrdiff_t)(target - (start_pc + 2)); // Prepend each BRASL with a nop.
const bool emit_target_to_pool = (tocOffset == -2) && !code_section()->scratch_emit();
const bool emit_relative_call = !emit_target_to_pool &&
RelAddr::is_in_range_of_RelAddr32(dist) &&
ReoptimizeCallSequences &&
!code_section()->scratch_emit();
if (emit_relative_call) {
// Add padding to get the same size as below.
const unsigned int padding = call_far_patchable_size() - call_far_pcrelative_size();
unsigned int current_padding;
for (current_padding = 0; current_padding < padding; current_padding += nop_size()) { z_nop(); }
assert(current_padding == padding, "sanity");
// relative call: len = 2(nop) + 6 (brasl)
// CodeBlob resize cannot occur in this case because
// this call is emitted into pre-existing space.
z_nop(); // Prepend each BRASL with a nop.
z_brasl(Z_R14, target);
} else {
// absolute call: Get address from TOC.
// len = (load TOC){6|0} + (load from TOC){6} + (basr){2} = {14|8}
if (emit_target_to_pool) {
// When emitting the call for the first time, we do not need to use
// the pc-relative version. It will be patched anyway, when the code
// buffer is copied.
// Relocation is not needed when !ReoptimizeCallSequences.
relocInfo::relocType rt = ReoptimizeCallSequences ? relocInfo::runtime_call_w_cp_type : relocInfo::none;
AddressLiteral dest(target, rt);
// Store_oop_in_toc() adds dest to the constant table. As side effect, this kills
// inst_mark(). Reset if possible.
bool reset_mark = (inst_mark() == pc());
tocOffset = store_oop_in_toc(dest);
if (reset_mark) { set_inst_mark(); }
if (tocOffset == -1) {
return false; // Couldn't create constant pool entry.
}
}
assert(offset() == start_off, "emit no code before this point!");
address tocPos = pc() + tocOffset;
if (emit_target_to_pool) {
tocPos = code()->consts()->start() + tocOffset;
}
load_long_pcrelative(Z_R14, tocPos);
z_basr(Z_R14, Z_R14);
}
#ifdef ASSERT
// Assert that we can identify the emitted call.
assert(is_call_far_patchable_at(addr_at(start_off)), "can't identify emitted call");
assert(offset() == start_off+call_far_patchable_size(), "wrong size");
if (emit_target_to_pool) {
assert(get_dest_of_call_far_patchable_at(addr_at(start_off), code()->consts()->start()) == target,
"wrong encoding of dest address");
}
#endif
return true; // success
}
// Identify a call_far_patchable instruction.
// For more detailed information see header comment of call_far_patchable.
bool MacroAssembler::is_call_far_patchable_at(address instruction_addr) {
return is_call_far_patchable_variant2_at(instruction_addr) || // short version: BRASL
is_call_far_patchable_variant0_at(instruction_addr); // long version LARL + LG + BASR
}
// Does the call_far_patchable instruction use a pc-relative encoding
// of the call destination?
bool MacroAssembler::is_call_far_patchable_pcrelative_at(address instruction_addr) {
// Variant 2 is pc-relative.
return is_call_far_patchable_variant2_at(instruction_addr);
}
bool MacroAssembler::is_call_far_pcrelative(address instruction_addr) {
// Prepend each BRASL with a nop.
return is_z_nop(instruction_addr) && is_z_brasl(instruction_addr + nop_size()); // Match at position after one nop required.
}
// Set destination address of a call_far_patchable instruction.
void MacroAssembler::set_dest_of_call_far_patchable_at(address instruction_addr, address dest, int64_t tocOffset) {
ResourceMark rm;
// Now that CP entry is verified, patch call to a pc-relative call (if circumstances permit).
int code_size = MacroAssembler::call_far_patchable_size();
CodeBuffer buf(instruction_addr, code_size);
MacroAssembler masm(&buf);
masm.call_far_patchable(dest, tocOffset);
ICache::invalidate_range(instruction_addr, code_size); // Empty on z.
}
// Get dest address of a call_far_patchable instruction.
address MacroAssembler::get_dest_of_call_far_patchable_at(address instruction_addr, address ctable) {
// Dynamic TOC: absolute address in constant pool.
// Check variant2 first, it is more frequent.
// Relative address encoded in call instruction.
if (is_call_far_patchable_variant2_at(instruction_addr)) {
return MacroAssembler::get_target_addr_pcrel(instruction_addr + nop_size()); // Prepend each BRASL with a nop.
// Absolute address in constant pool.
} else if (is_call_far_patchable_variant0_at(instruction_addr)) {
address iaddr = instruction_addr;
long tocOffset = get_load_const_from_toc_offset(iaddr);
address tocLoc = iaddr + tocOffset;
return *(address *)(tocLoc);
} else {
fprintf(stderr, "MacroAssembler::get_dest_of_call_far_patchable_at has a problem at %p:\n", instruction_addr);
fprintf(stderr, "not a call_far_patchable: %16.16lx %16.16lx, len = %d\n",
*(unsigned long*)instruction_addr,
*(unsigned long*)(instruction_addr+8),
call_far_patchable_size());
Disassembler::decode(instruction_addr, instruction_addr+call_far_patchable_size());
ShouldNotReachHere();
return NULL;
}
}
void MacroAssembler::align_call_far_patchable(address pc) {
if (call_far_patchable_requires_alignment_nop(pc)) { z_nop(); }
}
void MacroAssembler::check_and_handle_earlyret(Register java_thread) {
}
void MacroAssembler::check_and_handle_popframe(Register java_thread) {
}
// Read from the polling page.
// Use TM or TMY instruction, depending on read offset.
// offset = 0: Use TM, safepoint polling.
// offset < 0: Use TMY, profiling safepoint polling.
void MacroAssembler::load_from_polling_page(Register polling_page_address, int64_t offset) {
if (Immediate::is_uimm12(offset)) {
z_tm(offset, polling_page_address, mask_safepoint);
} else {
z_tmy(offset, polling_page_address, mask_profiling);
}
}
// Check whether z_instruction is a read access to the polling page
// which was emitted by load_from_polling_page(..).
bool MacroAssembler::is_load_from_polling_page(address instr_loc) {
unsigned long z_instruction;
unsigned int ilen = get_instruction(instr_loc, &z_instruction);
if (ilen == 2) { return false; } // It's none of the allowed instructions.
if (ilen == 4) {
if (!is_z_tm(z_instruction)) { return false; } // It's len=4, but not a z_tm. fail.
int ms = inv_mask(z_instruction,8,32); // mask
int ra = inv_reg(z_instruction,16,32); // base register
int ds = inv_uimm12(z_instruction); // displacement
if (!(ds == 0 && ra != 0 && ms == mask_safepoint)) {
return false; // It's not a z_tm(0, ra, mask_safepoint). Fail.
}
} else { /* if (ilen == 6) */
assert(!is_z_lg(z_instruction), "old form (LG) polling page access. Please fix and use TM(Y).");
if (!is_z_tmy(z_instruction)) { return false; } // It's len=6, but not a z_tmy. fail.
int ms = inv_mask(z_instruction,8,48); // mask
int ra = inv_reg(z_instruction,16,48); // base register
int ds = inv_simm20(z_instruction); // displacement
}
return true;
}
// Extract poll address from instruction and ucontext.
address MacroAssembler::get_poll_address(address instr_loc, void* ucontext) {
assert(ucontext != NULL, "must have ucontext");
ucontext_t* uc = (ucontext_t*) ucontext;
unsigned long z_instruction;
unsigned int ilen = get_instruction(instr_loc, &z_instruction);
if (ilen == 4 && is_z_tm(z_instruction)) {
int ra = inv_reg(z_instruction, 16, 32); // base register
int ds = inv_uimm12(z_instruction); // displacement
address addr = (address)uc->uc_mcontext.gregs[ra];
return addr + ds;
} else if (ilen == 6 && is_z_tmy(z_instruction)) {
int ra = inv_reg(z_instruction, 16, 48); // base register
int ds = inv_simm20(z_instruction); // displacement
address addr = (address)uc->uc_mcontext.gregs[ra];
return addr + ds;
}
ShouldNotReachHere();
return NULL;
}
// Extract poll register from instruction.
uint MacroAssembler::get_poll_register(address instr_loc) {
unsigned long z_instruction;
unsigned int ilen = get_instruction(instr_loc, &z_instruction);
if (ilen == 4 && is_z_tm(z_instruction)) {
return (uint)inv_reg(z_instruction, 16, 32); // base register
} else if (ilen == 6 && is_z_tmy(z_instruction)) {
return (uint)inv_reg(z_instruction, 16, 48); // base register
}
ShouldNotReachHere();
return 0;
}
void MacroAssembler::safepoint_poll(Label& slow_path, Register temp_reg) {
if (SafepointMechanism::uses_thread_local_poll()) {
const Address poll_byte_addr(Z_thread, in_bytes(Thread::polling_page_offset()) + 7 /* Big Endian */);
// Armed page has poll_bit set.
z_tm(poll_byte_addr, SafepointMechanism::poll_bit());
z_brnaz(slow_path);
} else {
load_const_optimized(temp_reg, SafepointSynchronize::address_of_state());
z_cli(/*SafepointSynchronize::sz_state()*/4-1, temp_reg, SafepointSynchronize::_not_synchronized);
z_brne(slow_path);
}
}
// Don't rely on register locking, always use Z_R1 as scratch register instead.
void MacroAssembler::bang_stack_with_offset(int offset) {
// Stack grows down, caller passes positive offset.
assert(offset > 0, "must bang with positive offset");
if (Displacement::is_validDisp(-offset)) {
z_tmy(-offset, Z_SP, mask_stackbang);
} else {
add2reg(Z_R1, -offset, Z_SP); // Do not destroy Z_SP!!!
z_tm(0, Z_R1, mask_stackbang); // Just banging.
}
}
void MacroAssembler::reserved_stack_check(Register return_pc) {
// Test if reserved zone needs to be enabled.
Label no_reserved_zone_enabling;
assert(return_pc == Z_R14, "Return pc must be in R14 before z_br() to StackOverflow stub.");
BLOCK_COMMENT("reserved_stack_check {");
z_clg(Z_SP, Address(Z_thread, JavaThread::reserved_stack_activation_offset()));
z_brl(no_reserved_zone_enabling);
// Enable reserved zone again, throw stack overflow exception.
save_return_pc();
push_frame_abi160(0);
call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::enable_stack_reserved_zone), Z_thread);
pop_frame();
restore_return_pc();
load_const_optimized(Z_R1, StubRoutines::throw_delayed_StackOverflowError_entry());
// Don't use call() or z_basr(), they will invalidate Z_R14 which contains the return pc.
z_br(Z_R1);
should_not_reach_here();
bind(no_reserved_zone_enabling);
BLOCK_COMMENT("} reserved_stack_check");
}
// Defines obj, preserves var_size_in_bytes, okay for t2 == var_size_in_bytes.
void MacroAssembler::tlab_allocate(Register obj,
Register var_size_in_bytes,
int con_size_in_bytes,
Register t1,
Label& slow_case) {
assert_different_registers(obj, var_size_in_bytes, t1);
Register end = t1;
Register thread = Z_thread;
z_lg(obj, Address(thread, JavaThread::tlab_top_offset()));
if (var_size_in_bytes == noreg) {
z_lay(end, Address(obj, con_size_in_bytes));
} else {
z_lay(end, Address(obj, var_size_in_bytes));
}
z_cg(end, Address(thread, JavaThread::tlab_end_offset()));
branch_optimized(bcondHigh, slow_case);
// Update the tlab top pointer.
z_stg(end, Address(thread, JavaThread::tlab_top_offset()));
// Recover var_size_in_bytes if necessary.
if (var_size_in_bytes == end) {
z_sgr(var_size_in_bytes, obj);
}
}
// Emitter for interface method lookup.
// input: recv_klass, intf_klass, itable_index
// output: method_result
// kills: itable_index, temp1_reg, Z_R0, Z_R1
// TODO: Temp2_reg is unused. we may use this emitter also in the itable stubs.
// If the register is still not needed then, remove it.
void MacroAssembler::lookup_interface_method(Register recv_klass,
Register intf_klass,
RegisterOrConstant itable_index,
Register method_result,
Register temp1_reg,
Label& no_such_interface,
bool return_method) {
const Register vtable_len = temp1_reg; // Used to compute itable_entry_addr.
const Register itable_entry_addr = Z_R1_scratch;
const Register itable_interface = Z_R0_scratch;
BLOCK_COMMENT("lookup_interface_method {");
// Load start of itable entries into itable_entry_addr.
z_llgf(vtable_len, Address(recv_klass, Klass::vtable_length_offset()));
z_sllg(vtable_len, vtable_len, exact_log2(vtableEntry::size_in_bytes()));
// Loop over all itable entries until desired interfaceOop(Rinterface) found.
const int vtable_base_offset = in_bytes(Klass::vtable_start_offset());
add2reg_with_index(itable_entry_addr,
vtable_base_offset + itableOffsetEntry::interface_offset_in_bytes(),
recv_klass, vtable_len);
const int itable_offset_search_inc = itableOffsetEntry::size() * wordSize;
Label search;
bind(search);
// Handle IncompatibleClassChangeError.
// If the entry is NULL then we've reached the end of the table
// without finding the expected interface, so throw an exception.
load_and_test_long(itable_interface, Address(itable_entry_addr));
z_bre(no_such_interface);
add2reg(itable_entry_addr, itable_offset_search_inc);
z_cgr(itable_interface, intf_klass);
z_brne(search);
// Entry found and itable_entry_addr points to it, get offset of vtable for interface.
if (return_method) {
const int vtable_offset_offset = (itableOffsetEntry::offset_offset_in_bytes() -
itableOffsetEntry::interface_offset_in_bytes()) -
itable_offset_search_inc;
// Compute itableMethodEntry and get method and entry point
// we use addressing with index and displacement, since the formula
// for computing the entry's offset has a fixed and a dynamic part,
// the latter depending on the matched interface entry and on the case,
// that the itable index has been passed as a register, not a constant value.
int method_offset = itableMethodEntry::method_offset_in_bytes();
// Fixed part (displacement), common operand.
Register itable_offset = method_result; // Dynamic part (index register).
if (itable_index.is_register()) {
// Compute the method's offset in that register, for the formula, see the
// else-clause below.
z_sllg(itable_offset, itable_index.as_register(), exact_log2(itableMethodEntry::size() * wordSize));
z_agf(itable_offset, vtable_offset_offset, itable_entry_addr);
} else {
// Displacement increases.
method_offset += itableMethodEntry::size() * wordSize * itable_index.as_constant();
// Load index from itable.
z_llgf(itable_offset, vtable_offset_offset, itable_entry_addr);
}
// Finally load the method's oop.
z_lg(method_result, method_offset, itable_offset, recv_klass);
}
BLOCK_COMMENT("} lookup_interface_method");
}
// Lookup for virtual method invocation.
void MacroAssembler::lookup_virtual_method(Register recv_klass,
RegisterOrConstant vtable_index,
Register method_result) {
assert_different_registers(recv_klass, vtable_index.register_or_noreg());
assert(vtableEntry::size() * wordSize == wordSize,
"else adjust the scaling in the code below");
BLOCK_COMMENT("lookup_virtual_method {");
const int base = in_bytes(Klass::vtable_start_offset());
if (vtable_index.is_constant()) {
// Load with base + disp.
Address vtable_entry_addr(recv_klass,
vtable_index.as_constant() * wordSize +
base +
vtableEntry::method_offset_in_bytes());
z_lg(method_result, vtable_entry_addr);
} else {
// Shift index properly and load with base + index + disp.
Register vindex = vtable_index.as_register();
Address vtable_entry_addr(recv_klass, vindex,
base + vtableEntry::method_offset_in_bytes());
z_sllg(vindex, vindex, exact_log2(wordSize));
z_lg(method_result, vtable_entry_addr);
}
BLOCK_COMMENT("} lookup_virtual_method");
}
// Factor out code to call ic_miss_handler.
// Generate code to call the inline cache miss handler.
//
// In most cases, this code will be generated out-of-line.
// The method parameters are intended to provide some variability.
// ICM - Label which has to be bound to the start of useful code (past any traps).
// trapMarker - Marking byte for the generated illtrap instructions (if any).
// Any value except 0x00 is supported.
// = 0x00 - do not generate illtrap instructions.
// use nops to fill ununsed space.
// requiredSize - required size of the generated code. If the actually
// generated code is smaller, use padding instructions to fill up.
// = 0 - no size requirement, no padding.
// scratch - scratch register to hold branch target address.
//
// The method returns the code offset of the bound label.
unsigned int MacroAssembler::call_ic_miss_handler(Label& ICM, int trapMarker, int requiredSize, Register scratch) {
intptr_t startOffset = offset();
// Prevent entry at content_begin().
if (trapMarker != 0) {
z_illtrap(trapMarker);
}
// Load address of inline cache miss code into scratch register
// and branch to cache miss handler.
BLOCK_COMMENT("IC miss handler {");
BIND(ICM);
unsigned int labelOffset = offset();
AddressLiteral icmiss(SharedRuntime::get_ic_miss_stub());
load_const_optimized(scratch, icmiss);
z_br(scratch);
// Fill unused space.
if (requiredSize > 0) {
while ((offset() - startOffset) < requiredSize) {
if (trapMarker == 0) {
z_nop();
} else {
z_illtrap(trapMarker);
}
}
}
BLOCK_COMMENT("} IC miss handler");
return labelOffset;
}
void MacroAssembler::nmethod_UEP(Label& ic_miss) {
Register ic_reg = as_Register(Matcher::inline_cache_reg_encode());
int klass_offset = oopDesc::klass_offset_in_bytes();
if (!ImplicitNullChecks || MacroAssembler::needs_explicit_null_check(klass_offset)) {
if (VM_Version::has_CompareBranch()) {
z_cgij(Z_ARG1, 0, Assembler::bcondEqual, ic_miss);
} else {
z_ltgr(Z_ARG1, Z_ARG1);
z_bre(ic_miss);
}
}
// Compare cached class against klass from receiver.
compare_klass_ptr(ic_reg, klass_offset, Z_ARG1, false);
z_brne(ic_miss);
}
void MacroAssembler::check_klass_subtype_fast_path(Register sub_klass,
Register super_klass,
Register temp1_reg,
Label* L_success,
Label* L_failure,
Label* L_slow_path,
RegisterOrConstant super_check_offset) {
const int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
const int sco_offset = in_bytes(Klass::super_check_offset_offset());
bool must_load_sco = (super_check_offset.constant_or_zero() == -1);
bool need_slow_path = (must_load_sco ||
super_check_offset.constant_or_zero() == sc_offset);
// Input registers must not overlap.
assert_different_registers(sub_klass, super_klass, temp1_reg);
if (super_check_offset.is_register()) {
assert_different_registers(sub_klass, super_klass,
super_check_offset.as_register());
} else if (must_load_sco) {
assert(temp1_reg != noreg, "supply either a temp or a register offset");
}
const Register Rsuper_check_offset = temp1_reg;
NearLabel L_fallthrough;
int label_nulls = 0;
if (L_success == NULL) { L_success = &L_fallthrough; label_nulls++; }
if (L_failure == NULL) { L_failure = &L_fallthrough; label_nulls++; }
if (L_slow_path == NULL) { L_slow_path = &L_fallthrough; label_nulls++; }
assert(label_nulls <= 1 ||
(L_slow_path == &L_fallthrough && label_nulls <= 2 && !need_slow_path),
"at most one NULL in the batch, usually");
BLOCK_COMMENT("check_klass_subtype_fast_path {");
// If the pointers are equal, we are done (e.g., String[] elements).
// This self-check enables sharing of secondary supertype arrays among
// non-primary types such as array-of-interface. Otherwise, each such
// type would need its own customized SSA.
// We move this check to the front of the fast path because many
// type checks are in fact trivially successful in this manner,
// so we get a nicely predicted branch right at the start of the check.
compare64_and_branch(sub_klass, super_klass, bcondEqual, *L_success);
// Check the supertype display, which is uint.
if (must_load_sco) {
z_llgf(Rsuper_check_offset, sco_offset, super_klass);
super_check_offset = RegisterOrConstant(Rsuper_check_offset);
}
Address super_check_addr(sub_klass, super_check_offset, 0);
z_cg(super_klass, super_check_addr); // compare w/ displayed supertype
// This check has worked decisively for primary supers.
// Secondary supers are sought in the super_cache ('super_cache_addr').
// (Secondary supers are interfaces and very deeply nested subtypes.)
// This works in the same check above because of a tricky aliasing
// between the super_cache and the primary super display elements.
// (The 'super_check_addr' can address either, as the case requires.)
// Note that the cache is updated below if it does not help us find
// what we need immediately.
// So if it was a primary super, we can just fail immediately.
// Otherwise, it's the slow path for us (no success at this point).
// Hacked jmp, which may only be used just before L_fallthrough.
#define final_jmp(label) \
if (&(label) == &L_fallthrough) { /*do nothing*/ } \
else { branch_optimized(Assembler::bcondAlways, label); } /*omit semicolon*/
if (super_check_offset.is_register()) {
branch_optimized(Assembler::bcondEqual, *L_success);
z_cfi(super_check_offset.as_register(), sc_offset);
if (L_failure == &L_fallthrough) {
branch_optimized(Assembler::bcondEqual, *L_slow_path);
} else {
branch_optimized(Assembler::bcondNotEqual, *L_failure);
final_jmp(*L_slow_path);
}
} else if (super_check_offset.as_constant() == sc_offset) {
// Need a slow path; fast failure is impossible.
if (L_slow_path == &L_fallthrough) {
branch_optimized(Assembler::bcondEqual, *L_success);
} else {
branch_optimized(Assembler::bcondNotEqual, *L_slow_path);
final_jmp(*L_success);
}
} else {
// No slow path; it's a fast decision.
if (L_failure == &L_fallthrough) {
branch_optimized(Assembler::bcondEqual, *L_success);
} else {
branch_optimized(Assembler::bcondNotEqual, *L_failure);
final_jmp(*L_success);
}
}
bind(L_fallthrough);
#undef local_brc
#undef final_jmp
BLOCK_COMMENT("} check_klass_subtype_fast_path");
// fallthru (to slow path)
}
void MacroAssembler::check_klass_subtype_slow_path(Register Rsubklass,
Register Rsuperklass,
Register Rarray_ptr, // tmp
Register Rlength, // tmp
Label* L_success,
Label* L_failure) {
// Input registers must not overlap.
// Also check for R1 which is explicitely used here.
assert_different_registers(Z_R1, Rsubklass, Rsuperklass, Rarray_ptr, Rlength);
NearLabel L_fallthrough;
int label_nulls = 0;
if (L_success == NULL) { L_success = &L_fallthrough; label_nulls++; }
if (L_failure == NULL) { L_failure = &L_fallthrough; label_nulls++; }
assert(label_nulls <= 1, "at most one NULL in the batch");
const int ss_offset = in_bytes(Klass::secondary_supers_offset());
const int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
const int length_offset = Array<Klass*>::length_offset_in_bytes();
const int base_offset = Array<Klass*>::base_offset_in_bytes();
// Hacked jmp, which may only be used just before L_fallthrough.
#define final_jmp(label) \
if (&(label) == &L_fallthrough) { /*do nothing*/ } \
else branch_optimized(Assembler::bcondAlways, label) /*omit semicolon*/
NearLabel loop_iterate, loop_count, match;
BLOCK_COMMENT("check_klass_subtype_slow_path {");
z_lg(Rarray_ptr, ss_offset, Rsubklass);
load_and_test_int(Rlength, Address(Rarray_ptr, length_offset));
branch_optimized(Assembler::bcondZero, *L_failure);
// Oops in table are NO MORE compressed.
z_cg(Rsuperklass, base_offset, Rarray_ptr); // Check array element for match.
z_bre(match); // Shortcut for array length = 1.
// No match yet, so we must walk the array's elements.
z_lngfr(Rlength, Rlength);
z_sllg(Rlength, Rlength, LogBytesPerWord); // -#bytes of cache array
z_llill(Z_R1, BytesPerWord); // Set increment/end index.
add2reg(Rlength, 2 * BytesPerWord); // start index = -(n-2)*BytesPerWord
z_slgr(Rarray_ptr, Rlength); // start addr: += (n-2)*BytesPerWord
z_bru(loop_count);
BIND(loop_iterate);
z_cg(Rsuperklass, base_offset, Rlength, Rarray_ptr); // Check array element for match.
z_bre(match);
BIND(loop_count);
z_brxlg(Rlength, Z_R1, loop_iterate);
// Rsuperklass not found among secondary super classes -> failure.
branch_optimized(Assembler::bcondAlways, *L_failure);
// Got a hit. Return success (zero result). Set cache.
// Cache load doesn't happen here. For speed it is directly emitted by the compiler.
BIND(match);
z_stg(Rsuperklass, sc_offset, Rsubklass); // Save result to cache.
final_jmp(*L_success);
// Exit to the surrounding code.
BIND(L_fallthrough);
#undef local_brc
#undef final_jmp
BLOCK_COMMENT("} check_klass_subtype_slow_path");
}
// Emitter for combining fast and slow path.
void MacroAssembler::check_klass_subtype(Register sub_klass,
Register super_klass,
Register temp1_reg,
Register temp2_reg,
Label& L_success) {
NearLabel failure;
BLOCK_COMMENT(err_msg("check_klass_subtype(%s subclass of %s) {", sub_klass->name(), super_klass->name()));
check_klass_subtype_fast_path(sub_klass, super_klass, temp1_reg,
&L_success, &failure, NULL);
check_klass_subtype_slow_path(sub_klass, super_klass,
temp1_reg, temp2_reg, &L_success, NULL);
BIND(failure);
BLOCK_COMMENT("} check_klass_subtype");
}
void MacroAssembler::clinit_barrier(Register klass, Register thread, Label* L_fast_path, Label* L_slow_path) {
assert(L_fast_path != NULL || L_slow_path != NULL, "at least one is required");
Label L_fallthrough;
if (L_fast_path == NULL) {
L_fast_path = &L_fallthrough;
} else if (L_slow_path == NULL) {
L_slow_path = &L_fallthrough;
}
// Fast path check: class is fully initialized
z_cli(Address(klass, InstanceKlass::init_state_offset()), InstanceKlass::fully_initialized);
z_bre(*L_fast_path);
// Fast path check: current thread is initializer thread
z_cg(thread, Address(klass, InstanceKlass::init_thread_offset()));
if (L_slow_path == &L_fallthrough) {
z_bre(*L_fast_path);
} else if (L_fast_path == &L_fallthrough) {
z_brne(*L_slow_path);
} else {
Unimplemented();
}
bind(L_fallthrough);
}
// Increment a counter at counter_address when the eq condition code is
// set. Kills registers tmp1_reg and tmp2_reg and preserves the condition code.
void MacroAssembler::increment_counter_eq(address counter_address, Register tmp1_reg, Register tmp2_reg) {
Label l;
z_brne(l);
load_const(tmp1_reg, counter_address);
add2mem_32(Address(tmp1_reg), 1, tmp2_reg);
z_cr(tmp1_reg, tmp1_reg); // Set cc to eq.
bind(l);
}
// Semantics are dependent on the slow_case label:
// If the slow_case label is not NULL, failure to biased-lock the object
// transfers control to the location of the slow_case label. If the
// object could be biased-locked, control is transferred to the done label.
// The condition code is unpredictable.
//
// If the slow_case label is NULL, failure to biased-lock the object results
// in a transfer of control to the done label with a condition code of not_equal.
// If the biased-lock could be successfully obtained, control is transfered to
// the done label with a condition code of equal.
// It is mandatory to react on the condition code At the done label.
//
void MacroAssembler::biased_locking_enter(Register obj_reg,
Register mark_reg,
Register temp_reg,
Register temp2_reg, // May be Z_RO!
Label &done,
Label *slow_case) {
assert(UseBiasedLocking, "why call this otherwise?");
assert_different_registers(obj_reg, mark_reg, temp_reg, temp2_reg);
Label cas_label; // Try, if implemented, CAS locking. Fall thru to slow path otherwise.
BLOCK_COMMENT("biased_locking_enter {");
// Biased locking
// See whether the lock is currently biased toward our thread and
// whether the epoch is still valid.
// Note that the runtime guarantees sufficient alignment of JavaThread
// pointers to allow age to be placed into low bits.
assert(markWord::age_shift == markWord::lock_bits + markWord::biased_lock_bits,
"biased locking makes assumptions about bit layout");
z_lr(temp_reg, mark_reg);
z_nilf(temp_reg, markWord::biased_lock_mask_in_place);
z_chi(temp_reg, markWord::biased_lock_pattern);
z_brne(cas_label); // Try cas if object is not biased, i.e. cannot be biased locked.
load_prototype_header(temp_reg, obj_reg);
load_const_optimized(temp2_reg, ~((int) markWord::age_mask_in_place));
z_ogr(temp_reg, Z_thread);
z_xgr(temp_reg, mark_reg);
z_ngr(temp_reg, temp2_reg);
if (PrintBiasedLockingStatistics) {
increment_counter_eq((address) BiasedLocking::biased_lock_entry_count_addr(), mark_reg, temp2_reg);
// Restore mark_reg.
z_lg(mark_reg, oopDesc::mark_offset_in_bytes(), obj_reg);
}
branch_optimized(Assembler::bcondEqual, done); // Biased lock obtained, return success.
Label try_revoke_bias;
Label try_rebias;
Address mark_addr = Address(obj_reg, oopDesc::mark_offset_in_bytes());
//----------------------------------------------------------------------------
// At this point we know that the header has the bias pattern and
// that we are not the bias owner in the current epoch. We need to
// figure out more details about the state of the header in order to
// know what operations can be legally performed on the object's
// header.
// If the low three bits in the xor result aren't clear, that means
// the prototype header is no longer biased and we have to revoke
// the bias on this object.
z_tmll(temp_reg, markWord::biased_lock_mask_in_place);
z_brnaz(try_revoke_bias);
// Biasing is still enabled for this data type. See whether the
// epoch of the current bias is still valid, meaning that the epoch
// bits of the mark word are equal to the epoch bits of the
// prototype header. (Note that the prototype header's epoch bits
// only change at a safepoint.) If not, attempt to rebias the object
// toward the current thread. Note that we must be absolutely sure
// that the current epoch is invalid in order to do this because
// otherwise the manipulations it performs on the mark word are
// illegal.
z_tmll(temp_reg, markWord::epoch_mask_in_place);
z_brnaz(try_rebias);
//----------------------------------------------------------------------------
// The epoch of the current bias is still valid but we know nothing
// about the owner; it might be set or it might be clear. Try to
// acquire the bias of the object using an atomic operation. If this
// fails we will go in to the runtime to revoke the object's bias.
// Note that we first construct the presumed unbiased header so we
// don't accidentally blow away another thread's valid bias.
z_nilf(mark_reg, markWord::biased_lock_mask_in_place | markWord::age_mask_in_place |
markWord::epoch_mask_in_place);
z_lgr(temp_reg, Z_thread);
z_llgfr(mark_reg, mark_reg);
z_ogr(temp_reg, mark_reg);
assert(oopDesc::mark_offset_in_bytes() == 0, "offset of _mark is not 0");
z_csg(mark_reg, temp_reg, 0, obj_reg);
// If the biasing toward our thread failed, this means that
// another thread succeeded in biasing it toward itself and we
// need to revoke that bias. The revocation will occur in the
// interpreter runtime in the slow case.
if (PrintBiasedLockingStatistics) {
increment_counter_eq((address) BiasedLocking::anonymously_biased_lock_entry_count_addr(),
temp_reg, temp2_reg);
}
if (slow_case != NULL) {
branch_optimized(Assembler::bcondNotEqual, *slow_case); // Biased lock not obtained, need to go the long way.
}
branch_optimized(Assembler::bcondAlways, done); // Biased lock status given in condition code.
//----------------------------------------------------------------------------
bind(try_rebias);
// At this point we know the epoch has expired, meaning that the
// current "bias owner", if any, is actually invalid. Under these
// circumstances _only_, we are allowed to use the current header's
// value as the comparison value when doing the cas to acquire the
// bias in the current epoch. In other words, we allow transfer of
// the bias from one thread to another directly in this situation.
z_nilf(mark_reg, markWord::biased_lock_mask_in_place | markWord::age_mask_in_place | markWord::epoch_mask_in_place);
load_prototype_header(temp_reg, obj_reg);
z_llgfr(mark_reg, mark_reg);
z_ogr(temp_reg, Z_thread);
assert(oopDesc::mark_offset_in_bytes() == 0, "offset of _mark is not 0");
z_csg(mark_reg, temp_reg, 0, obj_reg);
// If the biasing toward our thread failed, this means that
// another thread succeeded in biasing it toward itself and we
// need to revoke that bias. The revocation will occur in the
// interpreter runtime in the slow case.
if (PrintBiasedLockingStatistics) {
increment_counter_eq((address) BiasedLocking::rebiased_lock_entry_count_addr(), temp_reg, temp2_reg);
}
if (slow_case != NULL) {
branch_optimized(Assembler::bcondNotEqual, *slow_case); // Biased lock not obtained, need to go the long way.
}
z_bru(done); // Biased lock status given in condition code.
//----------------------------------------------------------------------------
bind(try_revoke_bias);
// The prototype mark in the klass doesn't have the bias bit set any
// more, indicating that objects of this data type are not supposed
// to be biased any more. We are going to try to reset the mark of
// this object to the prototype value and fall through to the
// CAS-based locking scheme. Note that if our CAS fails, it means
// that another thread raced us for the privilege of revoking the
// bias of this particular object, so it's okay to continue in the
// normal locking code.
load_prototype_header(temp_reg, obj_reg);
assert(oopDesc::mark_offset_in_bytes() == 0, "offset of _mark is not 0");
z_csg(mark_reg, temp_reg, 0, obj_reg);
// Fall through to the normal CAS-based lock, because no matter what
// the result of the above CAS, some thread must have succeeded in
// removing the bias bit from the object's header.
if (PrintBiasedLockingStatistics) {
// z_cgr(mark_reg, temp2_reg);
increment_counter_eq((address) BiasedLocking::revoked_lock_entry_count_addr(), temp_reg, temp2_reg);
}
bind(cas_label);
BLOCK_COMMENT("} biased_locking_enter");
}
void MacroAssembler::biased_locking_exit(Register mark_addr, Register temp_reg, Label& done) {
// Check for biased locking unlock case, which is a no-op
// Note: we do not have to check the thread ID for two reasons.
// First, the interpreter checks for IllegalMonitorStateException at
// a higher level. Second, if the bias was revoked while we held the
// lock, the object could not be rebiased toward another thread, so
// the bias bit would be clear.
BLOCK_COMMENT("biased_locking_exit {");
z_lg(temp_reg, 0, mark_addr);
z_nilf(temp_reg, markWord::biased_lock_mask_in_place);
z_chi(temp_reg, markWord::biased_lock_pattern);
z_bre(done);
BLOCK_COMMENT("} biased_locking_exit");
}
void MacroAssembler::compiler_fast_lock_object(Register oop, Register box, Register temp1, Register temp2, bool try_bias) {
Register displacedHeader = temp1;
Register currentHeader = temp1;
Register temp = temp2;
NearLabel done, object_has_monitor;
BLOCK_COMMENT("compiler_fast_lock_object {");
// Load markWord from oop into mark.
z_lg(displacedHeader, 0, oop);
if (try_bias) {
biased_locking_enter(oop, displacedHeader, temp, Z_R0, done);
}
// Handle existing monitor.
// The object has an existing monitor iff (mark & monitor_value) != 0.
guarantee(Immediate::is_uimm16(markWord::monitor_value), "must be half-word");
z_lr(temp, displacedHeader);
z_nill(temp, markWord::monitor_value);
z_brne(object_has_monitor);
// Set mark to markWord | markWord::unlocked_value.
z_oill(displacedHeader, markWord::unlocked_value);
// Load Compare Value application register.
// Initialize the box (must happen before we update the object mark).
z_stg(displacedHeader, BasicLock::displaced_header_offset_in_bytes(), box);
// Memory Fence (in cmpxchgd)
// Compare object markWord with mark and if equal exchange scratch1 with object markWord.
// If the compare-and-swap succeeded, then we found an unlocked object and we
// have now locked it.
z_csg(displacedHeader, box, 0, oop);
assert(currentHeader==displacedHeader, "must be same register"); // Identified two registers from z/Architecture.
z_bre(done);
// We did not see an unlocked object so try the fast recursive case.
z_sgr(currentHeader, Z_SP);
load_const_optimized(temp, (~(os::vm_page_size()-1) | markWord::lock_mask_in_place));
z_ngr(currentHeader, temp);
// z_brne(done);
// z_release();
z_stg(currentHeader/*==0 or not 0*/, BasicLock::displaced_header_offset_in_bytes(), box);
z_bru(done);
Register zero = temp;
Register monitor_tagged = displacedHeader; // Tagged with markWord::monitor_value.
bind(object_has_monitor);
// The object's monitor m is unlocked iff m->owner == NULL,
// otherwise m->owner may contain a thread or a stack address.
//
// Try to CAS m->owner from NULL to current thread.
z_lghi(zero, 0);
// If m->owner is null, then csg succeeds and sets m->owner=THREAD and CR=EQ.
z_csg(zero, Z_thread, OM_OFFSET_NO_MONITOR_VALUE_TAG(owner), monitor_tagged);
// Store a non-null value into the box.
z_stg(box, BasicLock::displaced_header_offset_in_bytes(), box);
#ifdef ASSERT
z_brne(done);
// We've acquired the monitor, check some invariants.
// Invariant 1: _recursions should be 0.
asm_assert_mem8_is_zero(OM_OFFSET_NO_MONITOR_VALUE_TAG(recursions), monitor_tagged,
"monitor->_recursions should be 0", -1);
z_ltgr(zero, zero); // Set CR=EQ.
#endif
bind(done);
BLOCK_COMMENT("} compiler_fast_lock_object");
// If locking was successful, CR should indicate 'EQ'.
// The compiler or the native wrapper generates a branch to the runtime call
// _complete_monitor_locking_Java.
}
void MacroAssembler::compiler_fast_unlock_object(Register oop, Register box, Register temp1, Register temp2, bool try_bias) {
Register displacedHeader = temp1;
Register currentHeader = temp2;
Register temp = temp1;
Register monitor = temp2;
Label done, object_has_monitor;
BLOCK_COMMENT("compiler_fast_unlock_object {");
if (try_bias) {
biased_locking_exit(oop, currentHeader, done);
}
// Find the lock address and load the displaced header from the stack.
// if the displaced header is zero, we have a recursive unlock.
load_and_test_long(displacedHeader, Address(box, BasicLock::displaced_header_offset_in_bytes()));
z_bre(done);
// Handle existing monitor.
// The object has an existing monitor iff (mark & monitor_value) != 0.
z_lg(currentHeader, oopDesc::mark_offset_in_bytes(), oop);
guarantee(Immediate::is_uimm16(markWord::monitor_value), "must be half-word");
z_nill(currentHeader, markWord::monitor_value);
z_brne(object_has_monitor);
// Check if it is still a light weight lock, this is true if we see
// the stack address of the basicLock in the markWord of the object
// copy box to currentHeader such that csg does not kill it.
z_lgr(currentHeader, box);
z_csg(currentHeader, displacedHeader, 0, oop);
z_bru(done); // Csg sets CR as desired.
// Handle existing monitor.
bind(object_has_monitor);
z_lg(currentHeader, oopDesc::mark_offset_in_bytes(), oop); // CurrentHeader is tagged with monitor_value set.
load_and_test_long(temp, Address(currentHeader, OM_OFFSET_NO_MONITOR_VALUE_TAG(recursions)));
z_brne(done);
load_and_test_long(temp, Address(currentHeader, OM_OFFSET_NO_MONITOR_VALUE_TAG(owner)));
z_brne(done);
load_and_test_long(temp, Address(currentHeader, OM_OFFSET_NO_MONITOR_VALUE_TAG(EntryList)));
z_brne(done);
load_and_test_long(temp, Address(currentHeader, OM_OFFSET_NO_MONITOR_VALUE_TAG(cxq)));
z_brne(done);
z_release();
z_stg(temp/*=0*/, OM_OFFSET_NO_MONITOR_VALUE_TAG(owner), currentHeader);
bind(done);
BLOCK_COMMENT("} compiler_fast_unlock_object");
// flag == EQ indicates success
// flag == NE indicates failure
}
void MacroAssembler::resolve_jobject(Register value, Register tmp1, Register tmp2) {
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
bs->resolve_jobject(this, value, tmp1, tmp2);
}
// Last_Java_sp must comply to the rules in frame_s390.hpp.
void MacroAssembler::set_last_Java_frame(Register last_Java_sp, Register last_Java_pc, bool allow_relocation) {
BLOCK_COMMENT("set_last_Java_frame {");
// Always set last_Java_pc and flags first because once last_Java_sp
// is visible has_last_Java_frame is true and users will look at the
// rest of the fields. (Note: flags should always be zero before we
// get here so doesn't need to be set.)
// Verify that last_Java_pc was zeroed on return to Java.
if (allow_relocation) {
asm_assert_mem8_is_zero(in_bytes(JavaThread::last_Java_pc_offset()),
Z_thread,
"last_Java_pc not zeroed before leaving Java",
0x200);
} else {
asm_assert_mem8_is_zero_static(in_bytes(JavaThread::last_Java_pc_offset()),
Z_thread,
"last_Java_pc not zeroed before leaving Java",
0x200);
}
// When returning from calling out from Java mode the frame anchor's
// last_Java_pc will always be set to NULL. It is set here so that
// if we are doing a call to native (not VM) that we capture the
// known pc and don't have to rely on the native call having a
// standard frame linkage where we can find the pc.
if (last_Java_pc!=noreg) {
z_stg(last_Java_pc, Address(Z_thread, JavaThread::last_Java_pc_offset()));
}
// This membar release is not required on z/Architecture, since the sequence of stores
// in maintained. Nevertheless, we leave it in to document the required ordering.
// The implementation of z_release() should be empty.
// z_release();
z_stg(last_Java_sp, Address(Z_thread, JavaThread::last_Java_sp_offset()));
BLOCK_COMMENT("} set_last_Java_frame");
}
void MacroAssembler::reset_last_Java_frame(bool allow_relocation) {
BLOCK_COMMENT("reset_last_Java_frame {");
if (allow_relocation) {
asm_assert_mem8_isnot_zero(in_bytes(JavaThread::last_Java_sp_offset()),
Z_thread,
"SP was not set, still zero",
0x202);
} else {
asm_assert_mem8_isnot_zero_static(in_bytes(JavaThread::last_Java_sp_offset()),
Z_thread,
"SP was not set, still zero",
0x202);
}
// _last_Java_sp = 0
// Clearing storage must be atomic here, so don't use clear_mem()!
store_const(Address(Z_thread, JavaThread::last_Java_sp_offset()), 0);
// _last_Java_pc = 0
store_const(Address(Z_thread, JavaThread::last_Java_pc_offset()), 0);
BLOCK_COMMENT("} reset_last_Java_frame");
return;
}
void MacroAssembler::set_top_ijava_frame_at_SP_as_last_Java_frame(Register sp, Register tmp1, bool allow_relocation) {
assert_different_registers(sp, tmp1);
// We cannot trust that code generated by the C++ compiler saves R14
// to z_abi_160.return_pc, because sometimes it spills R14 using stmg at
// z_abi_160.gpr14 (e.g. InterpreterRuntime::_new()).
// Therefore we load the PC into tmp1 and let set_last_Java_frame() save
// it into the frame anchor.
get_PC(tmp1);
set_last_Java_frame(/*sp=*/sp, /*pc=*/tmp1, allow_relocation);
}
void MacroAssembler::set_thread_state(JavaThreadState new_state) {
z_release();
assert(Immediate::is_uimm16(_thread_max_state), "enum value out of range for instruction");
assert(sizeof(JavaThreadState) == sizeof(int), "enum value must have base type int");
store_const(Address(Z_thread, JavaThread::thread_state_offset()), new_state, Z_R0, false);
}
void MacroAssembler::get_vm_result(Register oop_result) {
verify_thread();
z_lg(oop_result, Address(Z_thread, JavaThread::vm_result_offset()));
clear_mem(Address(Z_thread, JavaThread::vm_result_offset()), sizeof(void*));
verify_oop(oop_result);
}
void MacroAssembler::get_vm_result_2(Register result) {
verify_thread();
z_lg(result, Address(Z_thread, JavaThread::vm_result_2_offset()));
clear_mem(Address(Z_thread, JavaThread::vm_result_2_offset()), sizeof(void*));
}
// We require that C code which does not return a value in vm_result will
// leave it undisturbed.
void MacroAssembler::set_vm_result(Register oop_result) {
z_stg(oop_result, Address(Z_thread, JavaThread::vm_result_offset()));
}
// Explicit null checks (used for method handle code).
void MacroAssembler::null_check(Register reg, Register tmp, int64_t offset) {
if (!ImplicitNullChecks) {
NearLabel ok;
compare64_and_branch(reg, (intptr_t) 0, Assembler::bcondNotEqual, ok);
// We just put the address into reg if it was 0 (tmp==Z_R0 is allowed so we can't use it for the address).
address exception_entry = Interpreter::throw_NullPointerException_entry();
load_absolute_address(reg, exception_entry);
z_br(reg);
bind(ok);
} else {
if (needs_explicit_null_check((intptr_t)offset)) {
// Provoke OS NULL exception if reg = NULL by
// accessing M[reg] w/o changing any registers.
z_lg(tmp, 0, reg);
}
// else
// Nothing to do, (later) access of M[reg + offset]
// will provoke OS NULL exception if reg = NULL.
}
}
//-------------------------------------
// Compressed Klass Pointers
//-------------------------------------
// Klass oop manipulations if compressed.
void MacroAssembler::encode_klass_not_null(Register dst, Register src) {
Register current = (src != noreg) ? src : dst; // Klass is in dst if no src provided. (dst == src) also possible.
address base = CompressedKlassPointers::base();
int shift = CompressedKlassPointers::shift();
assert(UseCompressedClassPointers, "only for compressed klass ptrs");
BLOCK_COMMENT("cKlass encoder {");
#ifdef ASSERT
Label ok;
z_tmll(current, KlassAlignmentInBytes-1); // Check alignment.
z_brc(Assembler::bcondAllZero, ok);
// The plain disassembler does not recognize illtrap. It instead displays
// a 32-bit value. Issueing two illtraps assures the disassembler finds
// the proper beginning of the next instruction.
z_illtrap(0xee);
z_illtrap(0xee);
bind(ok);
#endif
if (base != NULL) {
unsigned int base_h = ((unsigned long)base)>>32;
unsigned int base_l = (unsigned int)((unsigned long)base);
if ((base_h != 0) && (base_l == 0) && VM_Version::has_HighWordInstr()) {
lgr_if_needed(dst, current);
z_aih(dst, -((int)base_h)); // Base has no set bits in lower half.
} else if ((base_h == 0) && (base_l != 0)) {
lgr_if_needed(dst, current);
z_agfi(dst, -(int)base_l);
} else {
load_const(Z_R0, base);
lgr_if_needed(dst, current);
z_sgr(dst, Z_R0);
}
current = dst;
}
if (shift != 0) {
assert (LogKlassAlignmentInBytes == shift, "decode alg wrong");
z_srlg(dst, current, shift);
current = dst;
}
lgr_if_needed(dst, current); // Move may be required (if neither base nor shift != 0).
BLOCK_COMMENT("} cKlass encoder");
}
// This function calculates the size of the code generated by
// decode_klass_not_null(register dst, Register src)
// when (Universe::heap() != NULL). Hence, if the instructions
// it generates change, then this method needs to be updated.
int MacroAssembler::instr_size_for_decode_klass_not_null() {
address base = CompressedKlassPointers::base();
int shift_size = CompressedKlassPointers::shift() == 0 ? 0 : 6; /* sllg */
int addbase_size = 0;
assert(UseCompressedClassPointers, "only for compressed klass ptrs");
if (base != NULL) {
unsigned int base_h = ((unsigned long)base)>>32;
unsigned int base_l = (unsigned int)((unsigned long)base);
if ((base_h != 0) && (base_l == 0) && VM_Version::has_HighWordInstr()) {
addbase_size += 6; /* aih */
} else if ((base_h == 0) && (base_l != 0)) {
addbase_size += 6; /* algfi */
} else {
addbase_size += load_const_size();
addbase_size += 4; /* algr */
}
}
#ifdef ASSERT
addbase_size += 10;
addbase_size += 2; // Extra sigill.
#endif
return addbase_size + shift_size;
}
// !!! If the instructions that get generated here change
// then function instr_size_for_decode_klass_not_null()
// needs to get updated.
// This variant of decode_klass_not_null() must generate predictable code!
// The code must only depend on globally known parameters.
void MacroAssembler::decode_klass_not_null(Register dst) {
address base = CompressedKlassPointers::base();
int shift = CompressedKlassPointers::shift();
int beg_off = offset();
assert(UseCompressedClassPointers, "only for compressed klass ptrs");
BLOCK_COMMENT("cKlass decoder (const size) {");
if (shift != 0) { // Shift required?
z_sllg(dst, dst, shift);
}
if (base != NULL) {
unsigned int base_h = ((unsigned long)base)>>32;
unsigned int base_l = (unsigned int)((unsigned long)base);
if ((base_h != 0) && (base_l == 0) && VM_Version::has_HighWordInstr()) {
z_aih(dst, base_h); // Base has no set bits in lower half.
} else if ((base_h == 0) && (base_l != 0)) {
z_algfi(dst, base_l); // Base has no set bits in upper half.
} else {
load_const(Z_R0, base); // Base has set bits everywhere.
z_algr(dst, Z_R0);
}
}
#ifdef ASSERT
Label ok;
z_tmll(dst, KlassAlignmentInBytes-1); // Check alignment.
z_brc(Assembler::bcondAllZero, ok);
// The plain disassembler does not recognize illtrap. It instead displays
// a 32-bit value. Issueing two illtraps assures the disassembler finds
// the proper beginning of the next instruction.
z_illtrap(0xd1);
z_illtrap(0xd1);
bind(ok);
#endif
assert(offset() == beg_off + instr_size_for_decode_klass_not_null(), "Code gen mismatch.");
BLOCK_COMMENT("} cKlass decoder (const size)");
}
// This variant of decode_klass_not_null() is for cases where
// 1) the size of the generated instructions may vary
// 2) the result is (potentially) stored in a register different from the source.
void MacroAssembler::decode_klass_not_null(Register dst, Register src) {
address base = CompressedKlassPointers::base();
int shift = CompressedKlassPointers::shift();
assert(UseCompressedClassPointers, "only for compressed klass ptrs");
BLOCK_COMMENT("cKlass decoder {");
if (src == noreg) src = dst;
if (shift != 0) { // Shift or at least move required?
z_sllg(dst, src, shift);
} else {
lgr_if_needed(dst, src);
}
if (base != NULL) {
unsigned int base_h = ((unsigned long)base)>>32;
unsigned int base_l = (unsigned int)((unsigned long)base);
if ((base_h != 0) && (base_l == 0) && VM_Version::has_HighWordInstr()) {
z_aih(dst, base_h); // Base has not set bits in lower half.
} else if ((base_h == 0) && (base_l != 0)) {
z_algfi(dst, base_l); // Base has no set bits in upper half.
} else {
load_const_optimized(Z_R0, base); // Base has set bits everywhere.
z_algr(dst, Z_R0);
}
}
#ifdef ASSERT
Label ok;
z_tmll(dst, KlassAlignmentInBytes-1); // Check alignment.
z_brc(Assembler::bcondAllZero, ok);
// The plain disassembler does not recognize illtrap. It instead displays
// a 32-bit value. Issueing two illtraps assures the disassembler finds
// the proper beginning of the next instruction.
z_illtrap(0xd2);
z_illtrap(0xd2);
bind(ok);
#endif
BLOCK_COMMENT("} cKlass decoder");
}
void MacroAssembler::load_klass(Register klass, Address mem) {
if (UseCompressedClassPointers) {
z_llgf(klass, mem);
// Attention: no null check here!
decode_klass_not_null(klass);
} else {
z_lg(klass, mem);
}
}
void MacroAssembler::load_klass(Register klass, Register src_oop) {
if (UseCompressedClassPointers) {
z_llgf(klass, oopDesc::klass_offset_in_bytes(), src_oop);
// Attention: no null check here!
decode_klass_not_null(klass);
} else {
z_lg(klass, oopDesc::klass_offset_in_bytes(), src_oop);
}
}
void MacroAssembler::load_prototype_header(Register Rheader, Register Rsrc_oop) {
assert_different_registers(Rheader, Rsrc_oop);
load_klass(Rheader, Rsrc_oop);
z_lg(Rheader, Address(Rheader, Klass::prototype_header_offset()));
}
void MacroAssembler::store_klass(Register klass, Register dst_oop, Register ck) {
if (UseCompressedClassPointers) {
assert_different_registers(dst_oop, klass, Z_R0);
if (ck == noreg) ck = klass;
encode_klass_not_null(ck, klass);
z_st(ck, Address(dst_oop, oopDesc::klass_offset_in_bytes()));
} else {
z_stg(klass, Address(dst_oop, oopDesc::klass_offset_in_bytes()));
}
}
void MacroAssembler::store_klass_gap(Register s, Register d) {
if (UseCompressedClassPointers) {
assert(s != d, "not enough registers");
// Support s = noreg.
if (s != noreg) {
z_st(s, Address(d, oopDesc::klass_gap_offset_in_bytes()));
} else {
z_mvhi(Address(d, oopDesc::klass_gap_offset_in_bytes()), 0);
}
}
}
// Compare klass ptr in memory against klass ptr in register.
//
// Rop1 - klass in register, always uncompressed.
// disp - Offset of klass in memory, compressed/uncompressed, depending on runtime flag.
// Rbase - Base address of cKlass in memory.
// maybeNULL - True if Rop1 possibly is a NULL.
void MacroAssembler::compare_klass_ptr(Register Rop1, int64_t disp, Register Rbase, bool maybeNULL) {
BLOCK_COMMENT("compare klass ptr {");
if (UseCompressedClassPointers) {
const int shift = CompressedKlassPointers::shift();
address base = CompressedKlassPointers::base();
assert((shift == 0) || (shift == LogKlassAlignmentInBytes), "cKlass encoder detected bad shift");
assert_different_registers(Rop1, Z_R0);
assert_different_registers(Rop1, Rbase, Z_R1);
// First encode register oop and then compare with cOop in memory.
// This sequence saves an unnecessary cOop load and decode.
if (base == NULL) {
if (shift == 0) {
z_cl(Rop1, disp, Rbase); // Unscaled
} else {
z_srlg(Z_R0, Rop1, shift); // ZeroBased
z_cl(Z_R0, disp, Rbase);
}
} else { // HeapBased
#ifdef ASSERT
bool used_R0 = true;
bool used_R1 = true;
#endif
Register current = Rop1;
Label done;
if (maybeNULL) { // NULL ptr must be preserved!
z_ltgr(Z_R0, current);
z_bre(done);
current = Z_R0;
}
unsigned int base_h = ((unsigned long)base)>>32;
unsigned int base_l = (unsigned int)((unsigned long)base);
if ((base_h != 0) && (base_l == 0) && VM_Version::has_HighWordInstr()) {
lgr_if_needed(Z_R0, current);
z_aih(Z_R0, -((int)base_h)); // Base has no set bits in lower half.
} else if ((base_h == 0) && (base_l != 0)) {
lgr_if_needed(Z_R0, current);
z_agfi(Z_R0, -(int)base_l);
} else {
int pow2_offset = get_oop_base_complement(Z_R1, ((uint64_t)(intptr_t)base));
add2reg_with_index(Z_R0, pow2_offset, Z_R1, Rop1); // Subtract base by adding complement.
}
if (shift != 0) {
z_srlg(Z_R0, Z_R0, shift);
}
bind(done);
z_cl(Z_R0, disp, Rbase);
#ifdef ASSERT
if (used_R0) preset_reg(Z_R0, 0xb05bUL, 2);
if (used_R1) preset_reg(Z_R1, 0xb06bUL, 2);
#endif
}
} else {
z_clg(Rop1, disp, Z_R0, Rbase);
}
BLOCK_COMMENT("} compare klass ptr");
}
//---------------------------
// Compressed oops
//---------------------------
void MacroAssembler::encode_heap_oop(Register oop) {
oop_encoder(oop, oop, true /*maybe null*/);
}
void MacroAssembler::encode_heap_oop_not_null(Register oop) {
oop_encoder(oop, oop, false /*not null*/);
}
// Called with something derived from the oop base. e.g. oop_base>>3.
int MacroAssembler::get_oop_base_pow2_offset(uint64_t oop_base) {
unsigned int oop_base_ll = ((unsigned int)(oop_base >> 0)) & 0xffff;
unsigned int oop_base_lh = ((unsigned int)(oop_base >> 16)) & 0xffff;
unsigned int oop_base_hl = ((unsigned int)(oop_base >> 32)) & 0xffff;
unsigned int oop_base_hh = ((unsigned int)(oop_base >> 48)) & 0xffff;
unsigned int n_notzero_parts = (oop_base_ll == 0 ? 0:1)
+ (oop_base_lh == 0 ? 0:1)
+ (oop_base_hl == 0 ? 0:1)
+ (oop_base_hh == 0 ? 0:1);
assert(oop_base != 0, "This is for HeapBased cOops only");
if (n_notzero_parts != 1) { // Check if oop_base is just a few pages shy of a power of 2.
uint64_t pow2_offset = 0x10000 - oop_base_ll;
if (pow2_offset < 0x8000) { // This might not be necessary.
uint64_t oop_base2 = oop_base + pow2_offset;
oop_base_ll = ((unsigned int)(oop_base2 >> 0)) & 0xffff;
oop_base_lh = ((unsigned int)(oop_base2 >> 16)) & 0xffff;
oop_base_hl = ((unsigned int)(oop_base2 >> 32)) & 0xffff;
oop_base_hh = ((unsigned int)(oop_base2 >> 48)) & 0xffff;
n_notzero_parts = (oop_base_ll == 0 ? 0:1) +
(oop_base_lh == 0 ? 0:1) +
(oop_base_hl == 0 ? 0:1) +
(oop_base_hh == 0 ? 0:1);
if (n_notzero_parts == 1) {
assert(-(int64_t)pow2_offset != (int64_t)-1, "We use -1 to signal uninitialized base register");
return -pow2_offset;
}
}
}
return 0;
}
// If base address is offset from a straight power of two by just a few pages,
// return this offset to the caller for a possible later composite add.
// TODO/FIX: will only work correctly for 4k pages.
int MacroAssembler::get_oop_base(Register Rbase, uint64_t oop_base) {
int pow2_offset = get_oop_base_pow2_offset(oop_base);
load_const_optimized(Rbase, oop_base - pow2_offset); // Best job possible.
return pow2_offset;
}
int MacroAssembler::get_oop_base_complement(Register Rbase, uint64_t oop_base) {
int offset = get_oop_base(Rbase, oop_base);
z_lcgr(Rbase, Rbase);
return -offset;
}
// Compare compressed oop in memory against oop in register.
// Rop1 - Oop in register.
// disp - Offset of cOop in memory.
// Rbase - Base address of cOop in memory.
// maybeNULL - True if Rop1 possibly is a NULL.
// maybeNULLtarget - Branch target for Rop1 == NULL, if flow control shall NOT continue with compare instruction.
void MacroAssembler::compare_heap_oop(Register Rop1, Address mem, bool maybeNULL) {
Register Rbase = mem.baseOrR0();
Register Rindex = mem.indexOrR0();
int64_t disp = mem.disp();
const int shift = CompressedOops::shift();
address base = CompressedOops::base();
assert(UseCompressedOops, "must be on to call this method");
assert(Universe::heap() != NULL, "java heap must be initialized to call this method");
assert((shift == 0) || (shift == LogMinObjAlignmentInBytes), "cOop encoder detected bad shift");
assert_different_registers(Rop1, Z_R0);
assert_different_registers(Rop1, Rbase, Z_R1);
assert_different_registers(Rop1, Rindex, Z_R1);
BLOCK_COMMENT("compare heap oop {");
// First encode register oop and then compare with cOop in memory.
// This sequence saves an unnecessary cOop load and decode.
if (base == NULL) {
if (shift == 0) {
z_cl(Rop1, disp, Rindex, Rbase); // Unscaled
} else {
z_srlg(Z_R0, Rop1, shift); // ZeroBased
z_cl(Z_R0, disp, Rindex, Rbase);
}
} else { // HeapBased
#ifdef ASSERT
bool used_R0 = true;
bool used_R1 = true;
#endif
Label done;
int pow2_offset = get_oop_base_complement(Z_R1, ((uint64_t)(intptr_t)base));
if (maybeNULL) { // NULL ptr must be preserved!
z_ltgr(Z_R0, Rop1);
z_bre(done);
}
add2reg_with_index(Z_R0, pow2_offset, Z_R1, Rop1);
z_srlg(Z_R0, Z_R0, shift);
bind(done);
z_cl(Z_R0, disp, Rindex, Rbase);
#ifdef ASSERT
if (used_R0) preset_reg(Z_R0, 0xb05bUL, 2);
if (used_R1) preset_reg(Z_R1, 0xb06bUL, 2);
#endif
}
BLOCK_COMMENT("} compare heap oop");
}
void MacroAssembler::access_store_at(BasicType type, DecoratorSet decorators,
const Address& addr, Register val,
Register tmp1, Register tmp2, Register tmp3) {
assert((decorators & ~(AS_RAW | IN_HEAP | IN_NATIVE | IS_ARRAY | IS_NOT_NULL |
ON_UNKNOWN_OOP_REF)) == 0, "unsupported decorator");
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::store_at(this, decorators, type,
addr, val,
tmp1, tmp2, tmp3);
} else {
bs->store_at(this, decorators, type,
addr, val,
tmp1, tmp2, tmp3);
}
}
void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators,
const Address& addr, Register dst,
Register tmp1, Register tmp2, Label *is_null) {
assert((decorators & ~(AS_RAW | IN_HEAP | IN_NATIVE | IS_ARRAY | IS_NOT_NULL |
ON_PHANTOM_OOP_REF | ON_WEAK_OOP_REF)) == 0, "unsupported decorator");
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::load_at(this, decorators, type,
addr, dst,
tmp1, tmp2, is_null);
} else {
bs->load_at(this, decorators, type,
addr, dst,
tmp1, tmp2, is_null);
}
}
void MacroAssembler::load_heap_oop(Register dest, const Address &a,
Register tmp1, Register tmp2,
DecoratorSet decorators, Label *is_null) {
access_load_at(T_OBJECT, IN_HEAP | decorators, a, dest, tmp1, tmp2, is_null);
}
void MacroAssembler::store_heap_oop(Register Roop, const Address &a,
Register tmp1, Register tmp2, Register tmp3,
DecoratorSet decorators) {
access_store_at(T_OBJECT, IN_HEAP | decorators, a, Roop, tmp1, tmp2, tmp3);
}
//-------------------------------------------------
// Encode compressed oop. Generally usable encoder.
//-------------------------------------------------
// Rsrc - contains regular oop on entry. It remains unchanged.
// Rdst - contains compressed oop on exit.
// Rdst and Rsrc may indicate same register, in which case Rsrc does not remain unchanged.
//
// Rdst must not indicate scratch register Z_R1 (Z_R1_scratch) for functionality.
// Rdst should not indicate scratch register Z_R0 (Z_R0_scratch) for performance.
//
// only32bitValid is set, if later code only uses the lower 32 bits. In this
// case we must not fix the upper 32 bits.
void MacroAssembler::oop_encoder(Register Rdst, Register Rsrc, bool maybeNULL,
Register Rbase, int pow2_offset, bool only32bitValid) {
const address oop_base = CompressedOops::base();
const int oop_shift = CompressedOops::shift();
const bool disjoint = CompressedOops::base_disjoint();
assert(UseCompressedOops, "must be on to call this method");
assert(Universe::heap() != NULL, "java heap must be initialized to call this encoder");
assert((oop_shift == 0) || (oop_shift == LogMinObjAlignmentInBytes), "cOop encoder detected bad shift");
if (disjoint || (oop_base == NULL)) {
BLOCK_COMMENT("cOop encoder zeroBase {");
if (oop_shift == 0) {
if (oop_base != NULL && !only32bitValid) {
z_llgfr(Rdst, Rsrc); // Clear upper bits in case the register will be decoded again.
} else {
lgr_if_needed(Rdst, Rsrc);
}
} else {
z_srlg(Rdst, Rsrc, oop_shift);
if (oop_base != NULL && !only32bitValid) {
z_llgfr(Rdst, Rdst); // Clear upper bits in case the register will be decoded again.
}
}
BLOCK_COMMENT("} cOop encoder zeroBase");
return;
}
bool used_R0 = false;
bool used_R1 = false;
BLOCK_COMMENT("cOop encoder general {");
assert_different_registers(Rdst, Z_R1);
assert_different_registers(Rsrc, Rbase);
if (maybeNULL) {
Label done;
// We reorder shifting and subtracting, so that we can compare
// and shift in parallel:
//
// cycle 0: potential LoadN, base = <const>
// cycle 1: base = !base dst = src >> 3, cmp cr = (src != 0)
// cycle 2: if (cr) br, dst = dst + base + offset
// Get oop_base components.
if (pow2_offset == -1) {
if (Rdst == Rbase) {
if (Rdst == Z_R1 || Rsrc == Z_R1) {
Rbase = Z_R0;
used_R0 = true;
} else {
Rdst = Z_R1;
used_R1 = true;
}
}
if (Rbase == Z_R1) {
used_R1 = true;
}
pow2_offset = get_oop_base_complement(Rbase, ((uint64_t)(intptr_t)oop_base) >> oop_shift);
}
assert_different_registers(Rdst, Rbase);
// Check for NULL oop (must be left alone) and shift.
if (oop_shift != 0) { // Shift out alignment bits
if (((intptr_t)oop_base&0xc000000000000000L) == 0L) { // We are sure: no single address will have the leftmost bit set.
z_srag(Rdst, Rsrc, oop_shift); // Arithmetic shift sets the condition code.
} else {
z_srlg(Rdst, Rsrc, oop_shift);
z_ltgr(Rsrc, Rsrc); // This is the recommended way of testing for zero.
// This probably is faster, as it does not write a register. No!
// z_cghi(Rsrc, 0);
}
} else {
z_ltgr(Rdst, Rsrc); // Move NULL to result register.
}
z_bre(done);
// Subtract oop_base components.
if ((Rdst == Z_R0) || (Rbase == Z_R0)) {
z_algr(Rdst, Rbase);
if (pow2_offset != 0) { add2reg(Rdst, pow2_offset); }
} else {
add2reg_with_index(Rdst, pow2_offset, Rbase, Rdst);
}
if (!only32bitValid) {
z_llgfr(Rdst, Rdst); // Clear upper bits in case the register will be decoded again.
}
bind(done);
} else { // not null
// Get oop_base components.
if (pow2_offset == -1) {
pow2_offset = get_oop_base_complement(Rbase, (uint64_t)(intptr_t)oop_base);
}
// Subtract oop_base components and shift.
if (Rdst == Z_R0 || Rsrc == Z_R0 || Rbase == Z_R0) {
// Don't use lay instruction.
if (Rdst == Rsrc) {
z_algr(Rdst, Rbase);
} else {
lgr_if_needed(Rdst, Rbase);
z_algr(Rdst, Rsrc);
}
if (pow2_offset != 0) add2reg(Rdst, pow2_offset);
} else {
add2reg_with_index(Rdst, pow2_offset, Rbase, Rsrc);
}
if (oop_shift != 0) { // Shift out alignment bits.
z_srlg(Rdst, Rdst, oop_shift);
}
if (!only32bitValid) {
z_llgfr(Rdst, Rdst); // Clear upper bits in case the register will be decoded again.
}
}
#ifdef ASSERT
if (used_R0 && Rdst != Z_R0 && Rsrc != Z_R0) { preset_reg(Z_R0, 0xb01bUL, 2); }
if (used_R1 && Rdst != Z_R1 && Rsrc != Z_R1) { preset_reg(Z_R1, 0xb02bUL, 2); }
#endif
BLOCK_COMMENT("} cOop encoder general");
}
//-------------------------------------------------
// decode compressed oop. Generally usable decoder.
//-------------------------------------------------
// Rsrc - contains compressed oop on entry.
// Rdst - contains regular oop on exit.
// Rdst and Rsrc may indicate same register.
// Rdst must not be the same register as Rbase, if Rbase was preloaded (before call).
// Rdst can be the same register as Rbase. Then, either Z_R0 or Z_R1 must be available as scratch.
// Rbase - register to use for the base
// pow2_offset - offset of base to nice value. If -1, base must be loaded.
// For performance, it is good to
// - avoid Z_R0 for any of the argument registers.
// - keep Rdst and Rsrc distinct from Rbase. Rdst == Rsrc is ok for performance.
// - avoid Z_R1 for Rdst if Rdst == Rbase.
void MacroAssembler::oop_decoder(Register Rdst, Register Rsrc, bool maybeNULL, Register Rbase, int pow2_offset) {
const address oop_base = CompressedOops::base();
const int oop_shift = CompressedOops::shift();
const bool disjoint = CompressedOops::base_disjoint();
assert(UseCompressedOops, "must be on to call this method");
assert(Universe::heap() != NULL, "java heap must be initialized to call this decoder");
assert((oop_shift == 0) || (oop_shift == LogMinObjAlignmentInBytes),
"cOop encoder detected bad shift");
// cOops are always loaded zero-extended from memory. No explicit zero-extension necessary.
if (oop_base != NULL) {
unsigned int oop_base_hl = ((unsigned int)((uint64_t)(intptr_t)oop_base >> 32)) & 0xffff;
unsigned int oop_base_hh = ((unsigned int)((uint64_t)(intptr_t)oop_base >> 48)) & 0xffff;
unsigned int oop_base_hf = ((unsigned int)((uint64_t)(intptr_t)oop_base >> 32)) & 0xFFFFffff;
if (disjoint && (oop_base_hl == 0 || oop_base_hh == 0)) {
BLOCK_COMMENT("cOop decoder disjointBase {");
// We do not need to load the base. Instead, we can install the upper bits
// with an OR instead of an ADD.
Label done;
// Rsrc contains a narrow oop. Thus we are sure the leftmost <oop_shift> bits will never be set.
if (maybeNULL) { // NULL ptr must be preserved!
z_slag(Rdst, Rsrc, oop_shift); // Arithmetic shift sets the condition code.
z_bre(done);
} else {
z_sllg(Rdst, Rsrc, oop_shift); // Logical shift leaves condition code alone.
}
if ((oop_base_hl != 0) && (oop_base_hh != 0)) {
z_oihf(Rdst, oop_base_hf);
} else if (oop_base_hl != 0) {
z_oihl(Rdst, oop_base_hl);
} else {
assert(oop_base_hh != 0, "not heapbased mode");
z_oihh(Rdst, oop_base_hh);
}
bind(done);
BLOCK_COMMENT("} cOop decoder disjointBase");
} else {
BLOCK_COMMENT("cOop decoder general {");
// There are three decode steps:
// scale oop offset (shift left)
// get base (in reg) and pow2_offset (constant)
// add base, pow2_offset, and oop offset
// The following register overlap situations may exist:
// Rdst == Rsrc, Rbase any other
// not a problem. Scaling in-place leaves Rbase undisturbed.
// Loading Rbase does not impact the scaled offset.
// Rdst == Rbase, Rsrc any other
// scaling would destroy a possibly preloaded Rbase. Loading Rbase
// would destroy the scaled offset.
// Remedy: use Rdst_tmp if Rbase has been preloaded.
// use Rbase_tmp if base has to be loaded.
// Rsrc == Rbase, Rdst any other
// Only possible without preloaded Rbase.
// Loading Rbase does not destroy compressed oop because it was scaled into Rdst before.
// Rsrc == Rbase, Rdst == Rbase
// Only possible without preloaded Rbase.
// Loading Rbase would destroy compressed oop. Scaling in-place is ok.
// Remedy: use Rbase_tmp.
//
Label done;
Register Rdst_tmp = Rdst;
Register Rbase_tmp = Rbase;
bool used_R0 = false;
bool used_R1 = false;
bool base_preloaded = pow2_offset >= 0;
guarantee(!(base_preloaded && (Rsrc == Rbase)), "Register clash, check caller");
assert(oop_shift != 0, "room for optimization");
// Check if we need to use scratch registers.
if (Rdst == Rbase) {
assert(!(((Rdst == Z_R0) && (Rsrc == Z_R1)) || ((Rdst == Z_R1) && (Rsrc == Z_R0))), "need a scratch reg");
if (Rdst != Rsrc) {
if (base_preloaded) { Rdst_tmp = (Rdst == Z_R1) ? Z_R0 : Z_R1; }
else { Rbase_tmp = (Rdst == Z_R1) ? Z_R0 : Z_R1; }
} else {
Rbase_tmp = (Rdst == Z_R1) ? Z_R0 : Z_R1;
}
}
if (base_preloaded) lgr_if_needed(Rbase_tmp, Rbase);
// Scale oop and check for NULL.
// Rsrc contains a narrow oop. Thus we are sure the leftmost <oop_shift> bits will never be set.
if (maybeNULL) { // NULL ptr must be preserved!
z_slag(Rdst_tmp, Rsrc, oop_shift); // Arithmetic shift sets the condition code.
z_bre(done);
} else {
z_sllg(Rdst_tmp, Rsrc, oop_shift); // Logical shift leaves condition code alone.
}
// Get oop_base components.
if (!base_preloaded) {
pow2_offset = get_oop_base(Rbase_tmp, (uint64_t)(intptr_t)oop_base);
}
// Add up all components.
if ((Rbase_tmp == Z_R0) || (Rdst_tmp == Z_R0)) {
z_algr(Rdst_tmp, Rbase_tmp);
if (pow2_offset != 0) { add2reg(Rdst_tmp, pow2_offset); }
} else {
add2reg_with_index(Rdst_tmp, pow2_offset, Rbase_tmp, Rdst_tmp);
}
bind(done);
lgr_if_needed(Rdst, Rdst_tmp);
#ifdef ASSERT
if (used_R0 && Rdst != Z_R0 && Rsrc != Z_R0) { preset_reg(Z_R0, 0xb03bUL, 2); }
if (used_R1 && Rdst != Z_R1 && Rsrc != Z_R1) { preset_reg(Z_R1, 0xb04bUL, 2); }
#endif
BLOCK_COMMENT("} cOop decoder general");
}
} else {
BLOCK_COMMENT("cOop decoder zeroBase {");
if (oop_shift == 0) {
lgr_if_needed(Rdst, Rsrc);
} else {
z_sllg(Rdst, Rsrc, oop_shift);
}
BLOCK_COMMENT("} cOop decoder zeroBase");
}
}
// ((OopHandle)result).resolve();
void MacroAssembler::resolve_oop_handle(Register result) {
// OopHandle::resolve is an indirection.
z_lg(result, 0, result);
}
void MacroAssembler::load_mirror_from_const_method(Register mirror, Register const_method) {
mem2reg_opt(mirror, Address(const_method, ConstMethod::constants_offset()));
mem2reg_opt(mirror, Address(mirror, ConstantPool::pool_holder_offset_in_bytes()));
mem2reg_opt(mirror, Address(mirror, Klass::java_mirror_offset()));
resolve_oop_handle(mirror);
}
void MacroAssembler::load_method_holder(Register holder, Register method) {
mem2reg_opt(holder, Address(method, Method::const_offset()));
mem2reg_opt(holder, Address(holder, ConstMethod::constants_offset()));
mem2reg_opt(holder, Address(holder, ConstantPool::pool_holder_offset_in_bytes()));
}
//---------------------------------------------------------------
//--- Operations on arrays.
//---------------------------------------------------------------
// Compiler ensures base is doubleword aligned and cnt is #doublewords.
// Emitter does not KILL cnt and base arguments, since they need to be copied to
// work registers anyway.
// Actually, only r0, r1, and r5 are killed.
unsigned int MacroAssembler::Clear_Array(Register cnt_arg, Register base_pointer_arg, Register odd_tmp_reg) {
int block_start = offset();
Register dst_len = Z_R1; // Holds dst len for MVCLE.
Register dst_addr = Z_R0; // Holds dst addr for MVCLE.
Label doXC, doMVCLE, done;
BLOCK_COMMENT("Clear_Array {");
// Check for zero len and convert to long.
z_ltgfr(odd_tmp_reg, cnt_arg);
z_bre(done); // Nothing to do if len == 0.
// Prefetch data to be cleared.
if (VM_Version::has_Prefetch()) {
z_pfd(0x02, 0, Z_R0, base_pointer_arg);
z_pfd(0x02, 256, Z_R0, base_pointer_arg);
}
z_sllg(dst_len, odd_tmp_reg, 3); // #bytes to clear.
z_cghi(odd_tmp_reg, 32); // Check for len <= 256 bytes (<=32 DW).
z_brnh(doXC); // If so, use executed XC to clear.
// MVCLE: initialize long arrays (general case).
bind(doMVCLE);
z_lgr(dst_addr, base_pointer_arg);
// Pass 0 as source length to MVCLE: destination will be filled with padding byte 0.
// The even register of the register pair is not killed.
clear_reg(odd_tmp_reg, true, false);
MacroAssembler::move_long_ext(dst_addr, as_Register(odd_tmp_reg->encoding()-1), 0);
z_bru(done);
// XC: initialize short arrays.
Label XC_template; // Instr template, never exec directly!
bind(XC_template);
z_xc(0,0,base_pointer_arg,0,base_pointer_arg);
bind(doXC);
add2reg(dst_len, -1); // Get #bytes-1 for EXECUTE.
if (VM_Version::has_ExecuteExtensions()) {
z_exrl(dst_len, XC_template); // Execute XC with var. len.
} else {
z_larl(odd_tmp_reg, XC_template);
z_ex(dst_len,0,Z_R0,odd_tmp_reg); // Execute XC with var. len.
}
// z_bru(done); // fallthru
bind(done);
BLOCK_COMMENT("} Clear_Array");
int block_end = offset();
return block_end - block_start;
}
// Compiler ensures base is doubleword aligned and cnt is count of doublewords.
// Emitter does not KILL any arguments nor work registers.
// Emitter generates up to 16 XC instructions, depending on the array length.
unsigned int MacroAssembler::Clear_Array_Const(long cnt, Register base) {
int block_start = offset();
int off;
int lineSize_Bytes = AllocatePrefetchStepSize;
int lineSize_DW = AllocatePrefetchStepSize>>LogBytesPerWord;
bool doPrefetch = VM_Version::has_Prefetch();
int XC_maxlen = 256;
int numXCInstr = cnt > 0 ? (cnt*BytesPerWord-1)/XC_maxlen+1 : 0;
BLOCK_COMMENT("Clear_Array_Const {");
assert(cnt*BytesPerWord <= 4096, "ClearArrayConst can handle 4k only");
// Do less prefetching for very short arrays.
if (numXCInstr > 0) {
// Prefetch only some cache lines, then begin clearing.
if (doPrefetch) {
if (cnt*BytesPerWord <= lineSize_Bytes/4) { // If less than 1/4 of a cache line to clear,
z_pfd(0x02, 0, Z_R0, base); // prefetch just the first cache line.
} else {
assert(XC_maxlen == lineSize_Bytes, "ClearArrayConst needs 256B cache lines");
for (off = 0; (off < AllocatePrefetchLines) && (off <= numXCInstr); off ++) {
z_pfd(0x02, off*lineSize_Bytes, Z_R0, base);
}
}
}
for (off=0; off<(numXCInstr-1); off++) {
z_xc(off*XC_maxlen, XC_maxlen-1, base, off*XC_maxlen, base);
// Prefetch some cache lines in advance.
if (doPrefetch && (off <= numXCInstr-AllocatePrefetchLines)) {
z_pfd(0x02, (off+AllocatePrefetchLines)*lineSize_Bytes, Z_R0, base);
}
}
if (off*XC_maxlen < cnt*BytesPerWord) {
z_xc(off*XC_maxlen, (cnt*BytesPerWord-off*XC_maxlen)-1, base, off*XC_maxlen, base);
}
}
BLOCK_COMMENT("} Clear_Array_Const");
int block_end = offset();
return block_end - block_start;
}
// Compiler ensures base is doubleword aligned and cnt is #doublewords.
// Emitter does not KILL cnt and base arguments, since they need to be copied to
// work registers anyway.
// Actually, only r0, r1, (which are work registers) and odd_tmp_reg are killed.
//
// For very large arrays, exploit MVCLE H/W support.
// MVCLE instruction automatically exploits H/W-optimized page mover.
// - Bytes up to next page boundary are cleared with a series of XC to self.
// - All full pages are cleared with the page mover H/W assist.
// - Remaining bytes are again cleared by a series of XC to self.
//
unsigned int MacroAssembler::Clear_Array_Const_Big(long cnt, Register base_pointer_arg, Register odd_tmp_reg) {
int block_start = offset();
Register dst_len = Z_R1; // Holds dst len for MVCLE.
Register dst_addr = Z_R0; // Holds dst addr for MVCLE.
BLOCK_COMMENT("Clear_Array_Const_Big {");
// Get len to clear.
load_const_optimized(dst_len, (long)cnt*8L); // in Bytes = #DW*8
// Prepare other args to MVCLE.
z_lgr(dst_addr, base_pointer_arg);
// Pass 0 as source length to MVCLE: destination will be filled with padding byte 0.
// The even register of the register pair is not killed.
(void) clear_reg(odd_tmp_reg, true, false); // Src len of MVCLE is zero.
MacroAssembler::move_long_ext(dst_addr, as_Register(odd_tmp_reg->encoding() - 1), 0);
BLOCK_COMMENT("} Clear_Array_Const_Big");
int block_end = offset();
return block_end - block_start;
}
// Allocator.
unsigned int MacroAssembler::CopyRawMemory_AlignedDisjoint(Register src_reg, Register dst_reg,
Register cnt_reg,
Register tmp1_reg, Register tmp2_reg) {
// Tmp1 is oddReg.
// Tmp2 is evenReg.
int block_start = offset();
Label doMVC, doMVCLE, done, MVC_template;
BLOCK_COMMENT("CopyRawMemory_AlignedDisjoint {");
// Check for zero len and convert to long.
z_ltgfr(cnt_reg, cnt_reg); // Remember casted value for doSTG case.
z_bre(done); // Nothing to do if len == 0.
z_sllg(Z_R1, cnt_reg, 3); // Dst len in bytes. calc early to have the result ready.
z_cghi(cnt_reg, 32); // Check for len <= 256 bytes (<=32 DW).
z_brnh(doMVC); // If so, use executed MVC to clear.
bind(doMVCLE); // A lot of data (more than 256 bytes).
// Prep dest reg pair.
z_lgr(Z_R0, dst_reg); // dst addr
// Dst len already in Z_R1.
// Prep src reg pair.
z_lgr(tmp2_reg, src_reg); // src addr
z_lgr(tmp1_reg, Z_R1); // Src len same as dst len.
// Do the copy.
move_long_ext(Z_R0, tmp2_reg, 0xb0); // Bypass cache.
z_bru(done); // All done.
bind(MVC_template); // Just some data (not more than 256 bytes).
z_mvc(0, 0, dst_reg, 0, src_reg);
bind(doMVC);
if (VM_Version::has_ExecuteExtensions()) {
add2reg(Z_R1, -1);
} else {
add2reg(tmp1_reg, -1, Z_R1);
z_larl(Z_R1, MVC_template);
}
if (VM_Version::has_Prefetch()) {
z_pfd(1, 0,Z_R0,src_reg);
z_pfd(2, 0,Z_R0,dst_reg);
// z_pfd(1,256,Z_R0,src_reg); // Assume very short copy.
// z_pfd(2,256,Z_R0,dst_reg);
}
if (VM_Version::has_ExecuteExtensions()) {
z_exrl(Z_R1, MVC_template);
} else {
z_ex(tmp1_reg, 0, Z_R0, Z_R1);
}
bind(done);
BLOCK_COMMENT("} CopyRawMemory_AlignedDisjoint");
int block_end = offset();
return block_end - block_start;
}
//------------------------------------------------------
// Special String Intrinsics. Implementation
//------------------------------------------------------
// Intrinsics for CompactStrings
// Compress char[] to byte[].
// Restores: src, dst
// Uses: cnt
// Kills: tmp, Z_R0, Z_R1.
// Early clobber: result.
// Note:
// cnt is signed int. Do not rely on high word!
// counts # characters, not bytes.
// The result is the number of characters copied before the first incompatible character was found.
// If precise is true, the processing stops exactly at this point. Otherwise, the result may be off
// by a few bytes. The result always indicates the number of copied characters.
// When used as a character index, the returned value points to the first incompatible character.
//
// Note: Does not behave exactly like package private StringUTF16 compress java implementation in case of failure:
// - Different number of characters may have been written to dead array (if precise is false).
// - Returns a number <cnt instead of 0. (Result gets compared with cnt.)
unsigned int MacroAssembler::string_compress(Register result, Register src, Register dst, Register cnt,
Register tmp, bool precise) {
assert_different_registers(Z_R0, Z_R1, result, src, dst, cnt, tmp);
if (precise) {
BLOCK_COMMENT("encode_iso_array {");
} else {
BLOCK_COMMENT("string_compress {");
}
int block_start = offset();
Register Rsrc = src;
Register Rdst = dst;
Register Rix = tmp;
Register Rcnt = cnt;
Register Rmask = result; // holds incompatibility check mask until result value is stored.
Label ScalarShortcut, AllDone;
z_iilf(Rmask, 0xFF00FF00);
z_iihf(Rmask, 0xFF00FF00);
#if 0 // Sacrifice shortcuts for code compactness
{
//---< shortcuts for short strings (very frequent) >---
// Strings with 4 and 8 characters were fond to occur very frequently.
// Therefore, we handle them right away with minimal overhead.
Label skipShortcut, skip4Shortcut, skip8Shortcut;
Register Rout = Z_R0;
z_chi(Rcnt, 4);
z_brne(skip4Shortcut); // 4 characters are very frequent
z_lg(Z_R0, 0, Rsrc); // Treat exactly 4 characters specially.
if (VM_Version::has_DistinctOpnds()) {
Rout = Z_R0;
z_ngrk(Rix, Z_R0, Rmask);
} else {
Rout = Rix;
z_lgr(Rix, Z_R0);
z_ngr(Z_R0, Rmask);
}
z_brnz(skipShortcut);
z_stcmh(Rout, 5, 0, Rdst);
z_stcm(Rout, 5, 2, Rdst);
z_lgfr(result, Rcnt);
z_bru(AllDone);
bind(skip4Shortcut);
z_chi(Rcnt, 8);
z_brne(skip8Shortcut); // There's more to do...
z_lmg(Z_R0, Z_R1, 0, Rsrc); // Treat exactly 8 characters specially.
if (VM_Version::has_DistinctOpnds()) {
Rout = Z_R0;
z_ogrk(Rix, Z_R0, Z_R1);
z_ngr(Rix, Rmask);
} else {
Rout = Rix;
z_lgr(Rix, Z_R0);
z_ogr(Z_R0, Z_R1);
z_ngr(Z_R0, Rmask);
}
z_brnz(skipShortcut);
z_stcmh(Rout, 5, 0, Rdst);
z_stcm(Rout, 5, 2, Rdst);
z_stcmh(Z_R1, 5, 4, Rdst);
z_stcm(Z_R1, 5, 6, Rdst);
z_lgfr(result, Rcnt);
z_bru(AllDone);
bind(skip8Shortcut);
clear_reg(Z_R0, true, false); // #characters already processed (none). Precond for scalar loop.
z_brl(ScalarShortcut); // Just a few characters
bind(skipShortcut);
}
#endif
clear_reg(Z_R0); // make sure register is properly initialized.
if (VM_Version::has_VectorFacility()) {
const int min_vcnt = 32; // Minimum #characters required to use vector instructions.
// Otherwise just do nothing in vector mode.
// Must be multiple of 2*(vector register length in chars (8 HW = 128 bits)).
const int log_min_vcnt = exact_log2(min_vcnt);
Label VectorLoop, VectorDone, VectorBreak;
VectorRegister Vtmp1 = Z_V16;
VectorRegister Vtmp2 = Z_V17;
VectorRegister Vmask = Z_V18;
VectorRegister Vzero = Z_V19;
VectorRegister Vsrc_first = Z_V20;
VectorRegister Vsrc_last = Z_V23;
assert((Vsrc_last->encoding() - Vsrc_first->encoding() + 1) == min_vcnt/8, "logic error");
assert(VM_Version::has_DistinctOpnds(), "Assumption when has_VectorFacility()");
z_srak(Rix, Rcnt, log_min_vcnt); // # vector loop iterations
z_brz(VectorDone); // not enough data for vector loop
z_vzero(Vzero); // all zeroes
z_vgmh(Vmask, 0, 7); // generate 0xff00 mask for all 2-byte elements
z_sllg(Z_R0, Rix, log_min_vcnt); // remember #chars that will be processed by vector loop
bind(VectorLoop);
z_vlm(Vsrc_first, Vsrc_last, 0, Rsrc);
add2reg(Rsrc, min_vcnt*2);
//---< check for incompatible character >---
z_vo(Vtmp1, Z_V20, Z_V21);
z_vo(Vtmp2, Z_V22, Z_V23);
z_vo(Vtmp1, Vtmp1, Vtmp2);
z_vn(Vtmp1, Vtmp1, Vmask);
z_vceqhs(Vtmp1, Vtmp1, Vzero); // high half of all chars must be zero for successful compress.
z_bvnt(VectorBreak); // break vector loop if not all vector elements compare eq -> incompatible character found.
// re-process data from current iteration in break handler.
//---< pack & store characters >---
z_vpkh(Vtmp1, Z_V20, Z_V21); // pack (src1, src2) -> tmp1
z_vpkh(Vtmp2, Z_V22, Z_V23); // pack (src3, src4) -> tmp2
z_vstm(Vtmp1, Vtmp2, 0, Rdst); // store packed string
add2reg(Rdst, min_vcnt);
z_brct(Rix, VectorLoop);
z_bru(VectorDone);
bind(VectorBreak);
add2reg(Rsrc, -min_vcnt*2); // Fix Rsrc. Rsrc was already updated, but Rdst and Rix are not.
z_sll(Rix, log_min_vcnt); // # chars processed so far in VectorLoop, excl. current iteration.
z_sr(Z_R0, Rix); // correct # chars processed in total.
bind(VectorDone);
}
{
const int min_cnt = 8; // Minimum #characters required to use unrolled loop.
// Otherwise just do nothing in unrolled loop.
// Must be multiple of 8.
const int log_min_cnt = exact_log2(min_cnt);
Label UnrolledLoop, UnrolledDone, UnrolledBreak;
if (VM_Version::has_DistinctOpnds()) {
z_srk(Rix, Rcnt, Z_R0); // remaining # chars to compress in unrolled loop
} else {
z_lr(Rix, Rcnt);
z_sr(Rix, Z_R0);
}
z_sra(Rix, log_min_cnt); // unrolled loop count
z_brz(UnrolledDone);
bind(UnrolledLoop);
z_lmg(Z_R0, Z_R1, 0, Rsrc);
if (precise) {
z_ogr(Z_R1, Z_R0); // check all 8 chars for incompatibility
z_ngr(Z_R1, Rmask);
z_brnz(UnrolledBreak);
z_lg(Z_R1, 8, Rsrc); // reload destroyed register
z_stcmh(Z_R0, 5, 0, Rdst);
z_stcm(Z_R0, 5, 2, Rdst);
} else {
z_stcmh(Z_R0, 5, 0, Rdst);
z_stcm(Z_R0, 5, 2, Rdst);
z_ogr(Z_R0, Z_R1);
z_ngr(Z_R0, Rmask);
z_brnz(UnrolledBreak);
}
z_stcmh(Z_R1, 5, 4, Rdst);
z_stcm(Z_R1, 5, 6, Rdst);
add2reg(Rsrc, min_cnt*2);
add2reg(Rdst, min_cnt);
z_brct(Rix, UnrolledLoop);
z_lgfr(Z_R0, Rcnt); // # chars processed in total after unrolled loop.
z_nilf(Z_R0, ~(min_cnt-1));
z_tmll(Rcnt, min_cnt-1);
z_brnaz(ScalarShortcut); // if all bits zero, there is nothing left to do for scalar loop.
// Rix == 0 in all cases.
z_sllg(Z_R1, Rcnt, 1); // # src bytes already processed. Only lower 32 bits are valid!
// Z_R1 contents must be treated as unsigned operand! For huge strings,
// (Rcnt >= 2**30), the value may spill into the sign bit by sllg.
z_lgfr(result, Rcnt); // all characters processed.
z_slgfr(Rdst, Rcnt); // restore ptr
z_slgfr(Rsrc, Z_R1); // restore ptr, double the element count for Rsrc restore
z_bru(AllDone);
bind(UnrolledBreak);
z_lgfr(Z_R0, Rcnt); // # chars processed in total after unrolled loop
z_nilf(Z_R0, ~(min_cnt-1));
z_sll(Rix, log_min_cnt); // # chars not yet processed in UnrolledLoop (due to break), broken iteration not included.
z_sr(Z_R0, Rix); // fix # chars processed OK so far.
if (!precise) {
z_lgfr(result, Z_R0);
z_sllg(Z_R1, Z_R0, 1); // # src bytes already processed. Only lower 32 bits are valid!
// Z_R1 contents must be treated as unsigned operand! For huge strings,
// (Rcnt >= 2**30), the value may spill into the sign bit by sllg.
z_aghi(result, min_cnt/2); // min_cnt/2 characters have already been written
// but ptrs were not updated yet.
z_slgfr(Rdst, Z_R0); // restore ptr
z_slgfr(Rsrc, Z_R1); // restore ptr, double the element count for Rsrc restore
z_bru(AllDone);
}
bind(UnrolledDone);
}
{
Label ScalarLoop, ScalarDone, ScalarBreak;
bind(ScalarShortcut);
z_ltgfr(result, Rcnt);
z_brz(AllDone);
#if 0 // Sacrifice shortcuts for code compactness
{
//---< Special treatment for very short strings (one or two characters) >---
// For these strings, we are sure that the above code was skipped.
// Thus, no registers were modified, register restore is not required.
Label ScalarDoit, Scalar2Char;
z_chi(Rcnt, 2);
z_brh(ScalarDoit);
z_llh(Z_R1, 0, Z_R0, Rsrc);
z_bre(Scalar2Char);
z_tmll(Z_R1, 0xff00);
z_lghi(result, 0); // cnt == 1, first char invalid, no chars successfully processed
z_brnaz(AllDone);
z_stc(Z_R1, 0, Z_R0, Rdst);
z_lghi(result, 1);
z_bru(AllDone);
bind(Scalar2Char);
z_llh(Z_R0, 2, Z_R0, Rsrc);
z_tmll(Z_R1, 0xff00);
z_lghi(result, 0); // cnt == 2, first char invalid, no chars successfully processed
z_brnaz(AllDone);
z_stc(Z_R1, 0, Z_R0, Rdst);
z_tmll(Z_R0, 0xff00);
z_lghi(result, 1); // cnt == 2, second char invalid, one char successfully processed
z_brnaz(AllDone);
z_stc(Z_R0, 1, Z_R0, Rdst);
z_lghi(result, 2);
z_bru(AllDone);
bind(ScalarDoit);
}
#endif
if (VM_Version::has_DistinctOpnds()) {
z_srk(Rix, Rcnt, Z_R0); // remaining # chars to compress in unrolled loop
} else {
z_lr(Rix, Rcnt);
z_sr(Rix, Z_R0);
}
z_lgfr(result, Rcnt); // # processed characters (if all runs ok).
z_brz(ScalarDone); // uses CC from Rix calculation
bind(ScalarLoop);
z_llh(Z_R1, 0, Z_R0, Rsrc);
z_tmll(Z_R1, 0xff00);
z_brnaz(ScalarBreak);
z_stc(Z_R1, 0, Z_R0, Rdst);
add2reg(Rsrc, 2);
add2reg(Rdst, 1);
z_brct(Rix, ScalarLoop);
z_bru(ScalarDone);
bind(ScalarBreak);
z_sr(result, Rix);
bind(ScalarDone);
z_sgfr(Rdst, result); // restore ptr
z_sgfr(Rsrc, result); // restore ptr, double the element count for Rsrc restore
z_sgfr(Rsrc, result);
}
bind(AllDone);
if (precise) {
BLOCK_COMMENT("} encode_iso_array");
} else {
BLOCK_COMMENT("} string_compress");
}
return offset() - block_start;
}
// Inflate byte[] to char[].
unsigned int MacroAssembler::string_inflate_trot(Register src, Register dst, Register cnt, Register tmp) {
int block_start = offset();
BLOCK_COMMENT("string_inflate {");
Register stop_char = Z_R0;
Register table = Z_R1;
Register src_addr = tmp;
assert_different_registers(Z_R0, Z_R1, tmp, src, dst, cnt);
assert(dst->encoding()%2 == 0, "must be even reg");
assert(cnt->encoding()%2 == 1, "must be odd reg");
assert(cnt->encoding() - dst->encoding() == 1, "must be even/odd pair");
StubRoutines::zarch::generate_load_trot_table_addr(this, table); // kills Z_R0 (if ASSERT)
clear_reg(stop_char); // Stop character. Not used here, but initialized to have a defined value.
lgr_if_needed(src_addr, src);
z_llgfr(cnt, cnt); // # src characters, must be a positive simm32.
translate_ot(dst, src_addr, /* mask = */ 0x0001);
BLOCK_COMMENT("} string_inflate");
return offset() - block_start;
}
// Inflate byte[] to char[].
// Restores: src, dst
// Uses: cnt
// Kills: tmp, Z_R0, Z_R1.
// Note:
// cnt is signed int. Do not rely on high word!
// counts # characters, not bytes.
unsigned int MacroAssembler::string_inflate(Register src, Register dst, Register cnt, Register tmp) {
assert_different_registers(Z_R0, Z_R1, src, dst, cnt, tmp);
BLOCK_COMMENT("string_inflate {");
int block_start = offset();
Register Rcnt = cnt; // # characters (src: bytes, dst: char (2-byte)), remaining after current loop.
Register Rix = tmp; // loop index
Register Rsrc = src; // addr(src array)
Register Rdst = dst; // addr(dst array)
Label ScalarShortcut, AllDone;
#if 0 // Sacrifice shortcuts for code compactness
{
//---< shortcuts for short strings (very frequent) >---
Label skipShortcut, skip4Shortcut;
z_ltr(Rcnt, Rcnt); // absolutely nothing to do for strings of len == 0.
z_brz(AllDone);
clear_reg(Z_R0); // make sure registers are properly initialized.
clear_reg(Z_R1);
z_chi(Rcnt, 4);
z_brne(skip4Shortcut); // 4 characters are very frequent
z_icm(Z_R0, 5, 0, Rsrc); // Treat exactly 4 characters specially.
z_icm(Z_R1, 5, 2, Rsrc);
z_stm(Z_R0, Z_R1, 0, Rdst);
z_bru(AllDone);
bind(skip4Shortcut);
z_chi(Rcnt, 8);
z_brh(skipShortcut); // There's a lot to do...
z_lgfr(Z_R0, Rcnt); // remaining #characters (<= 8). Precond for scalar loop.
// This does not destroy the "register cleared" state of Z_R0.
z_brl(ScalarShortcut); // Just a few characters
z_icmh(Z_R0, 5, 0, Rsrc); // Treat exactly 8 characters specially.
z_icmh(Z_R1, 5, 4, Rsrc);
z_icm(Z_R0, 5, 2, Rsrc);
z_icm(Z_R1, 5, 6, Rsrc);
z_stmg(Z_R0, Z_R1, 0, Rdst);
z_bru(AllDone);
bind(skipShortcut);
}
#endif
clear_reg(Z_R0); // make sure register is properly initialized.
if (VM_Version::has_VectorFacility()) {
const int min_vcnt = 32; // Minimum #characters required to use vector instructions.
// Otherwise just do nothing in vector mode.
// Must be multiple of vector register length (16 bytes = 128 bits).
const int log_min_vcnt = exact_log2(min_vcnt);
Label VectorLoop, VectorDone;
assert(VM_Version::has_DistinctOpnds(), "Assumption when has_VectorFacility()");
z_srak(Rix, Rcnt, log_min_vcnt); // calculate # vector loop iterations
z_brz(VectorDone); // skip if none
z_sllg(Z_R0, Rix, log_min_vcnt); // remember #chars that will be processed by vector loop
bind(VectorLoop);
z_vlm(Z_V20, Z_V21, 0, Rsrc); // get next 32 characters (single-byte)
add2reg(Rsrc, min_vcnt);
z_vuplhb(Z_V22, Z_V20); // V2 <- (expand) V0(high)
z_vupllb(Z_V23, Z_V20); // V3 <- (expand) V0(low)
z_vuplhb(Z_V24, Z_V21); // V4 <- (expand) V1(high)
z_vupllb(Z_V25, Z_V21); // V5 <- (expand) V1(low)
z_vstm(Z_V22, Z_V25, 0, Rdst); // store next 32 bytes
add2reg(Rdst, min_vcnt*2);
z_brct(Rix, VectorLoop);
bind(VectorDone);
}
const int min_cnt = 8; // Minimum #characters required to use unrolled scalar loop.
// Otherwise just do nothing in unrolled scalar mode.
// Must be multiple of 8.
{
const int log_min_cnt = exact_log2(min_cnt);
Label UnrolledLoop, UnrolledDone;
if (VM_Version::has_DistinctOpnds()) {
z_srk(Rix, Rcnt, Z_R0); // remaining # chars to process in unrolled loop
} else {
z_lr(Rix, Rcnt);
z_sr(Rix, Z_R0);
}
z_sra(Rix, log_min_cnt); // unrolled loop count
z_brz(UnrolledDone);
clear_reg(Z_R0);
clear_reg(Z_R1);
bind(UnrolledLoop);
z_icmh(Z_R0, 5, 0, Rsrc);
z_icmh(Z_R1, 5, 4, Rsrc);
z_icm(Z_R0, 5, 2, Rsrc);
z_icm(Z_R1, 5, 6, Rsrc);
add2reg(Rsrc, min_cnt);
z_stmg(Z_R0, Z_R1, 0, Rdst);
add2reg(Rdst, min_cnt*2);
z_brct(Rix, UnrolledLoop);
bind(UnrolledDone);
z_lgfr(Z_R0, Rcnt); // # chars left over after unrolled loop.
z_nilf(Z_R0, min_cnt-1);
z_brnz(ScalarShortcut); // if zero, there is nothing left to do for scalar loop.
// Rix == 0 in all cases.
z_sgfr(Z_R0, Rcnt); // negative # characters the ptrs have been advanced previously.
z_agr(Rdst, Z_R0); // restore ptr, double the element count for Rdst restore.
z_agr(Rdst, Z_R0);
z_agr(Rsrc, Z_R0); // restore ptr.
z_bru(AllDone);
}
{
bind(ScalarShortcut);
// Z_R0 must contain remaining # characters as 64-bit signed int here.
// register contents is preserved over scalar processing (for register fixup).
#if 0 // Sacrifice shortcuts for code compactness
{
Label ScalarDefault;
z_chi(Rcnt, 2);
z_brh(ScalarDefault);
z_llc(Z_R0, 0, Z_R0, Rsrc); // 6 bytes
z_sth(Z_R0, 0, Z_R0, Rdst); // 4 bytes
z_brl(AllDone);
z_llc(Z_R0, 1, Z_R0, Rsrc); // 6 bytes
z_sth(Z_R0, 2, Z_R0, Rdst); // 4 bytes
z_bru(AllDone);
bind(ScalarDefault);
}
#endif
Label CodeTable;
// Some comments on Rix calculation:
// - Rcnt is small, therefore no bits shifted out of low word (sll(g) instructions).
// - high word of both Rix and Rcnt may contain garbage
// - the final lngfr takes care of that garbage, extending the sign to high word
z_sllg(Rix, Z_R0, 2); // calculate 10*Rix = (4*Rix + Rix)*2
z_ar(Rix, Z_R0);
z_larl(Z_R1, CodeTable);
z_sll(Rix, 1);
z_lngfr(Rix, Rix); // ix range: [0..7], after inversion & mult: [-(7*12)..(0*12)].
z_bc(Assembler::bcondAlways, 0, Rix, Z_R1);
z_llc(Z_R1, 6, Z_R0, Rsrc); // 6 bytes
z_sth(Z_R1, 12, Z_R0, Rdst); // 4 bytes
z_llc(Z_R1, 5, Z_R0, Rsrc);
z_sth(Z_R1, 10, Z_R0, Rdst);
z_llc(Z_R1, 4, Z_R0, Rsrc);
z_sth(Z_R1, 8, Z_R0, Rdst);
z_llc(Z_R1, 3, Z_R0, Rsrc);
z_sth(Z_R1, 6, Z_R0, Rdst);
z_llc(Z_R1, 2, Z_R0, Rsrc);
z_sth(Z_R1, 4, Z_R0, Rdst);
z_llc(Z_R1, 1, Z_R0, Rsrc);
z_sth(Z_R1, 2, Z_R0, Rdst);
z_llc(Z_R1, 0, Z_R0, Rsrc);
z_sth(Z_R1, 0, Z_R0, Rdst);
bind(CodeTable);
z_chi(Rcnt, 8); // no fixup for small strings. Rdst, Rsrc were not modified.
z_brl(AllDone);
z_sgfr(Z_R0, Rcnt); // # characters the ptrs have been advanced previously.
z_agr(Rdst, Z_R0); // restore ptr, double the element count for Rdst restore.
z_agr(Rdst, Z_R0);
z_agr(Rsrc, Z_R0); // restore ptr.
}
bind(AllDone);
BLOCK_COMMENT("} string_inflate");
return offset() - block_start;
}
// Inflate byte[] to char[], length known at compile time.
// Restores: src, dst
// Kills: tmp, Z_R0, Z_R1.
// Note:
// len is signed int. Counts # characters, not bytes.
unsigned int MacroAssembler::string_inflate_const(Register src, Register dst, Register tmp, int len) {
assert_different_registers(Z_R0, Z_R1, src, dst, tmp);
BLOCK_COMMENT("string_inflate_const {");
int block_start = offset();
Register Rix = tmp; // loop index
Register Rsrc = src; // addr(src array)
Register Rdst = dst; // addr(dst array)
Label ScalarShortcut, AllDone;
int nprocessed = 0;
int src_off = 0; // compensate for saved (optimized away) ptr advancement.
int dst_off = 0; // compensate for saved (optimized away) ptr advancement.
bool restore_inputs = false;
bool workreg_clear = false;
if ((len >= 32) && VM_Version::has_VectorFacility()) {
const int min_vcnt = 32; // Minimum #characters required to use vector instructions.
// Otherwise just do nothing in vector mode.
// Must be multiple of vector register length (16 bytes = 128 bits).
const int log_min_vcnt = exact_log2(min_vcnt);
const int iterations = (len - nprocessed) >> log_min_vcnt;
nprocessed += iterations << log_min_vcnt;
Label VectorLoop;
if (iterations == 1) {
z_vlm(Z_V20, Z_V21, 0+src_off, Rsrc); // get next 32 characters (single-byte)
z_vuplhb(Z_V22, Z_V20); // V2 <- (expand) V0(high)
z_vupllb(Z_V23, Z_V20); // V3 <- (expand) V0(low)
z_vuplhb(Z_V24, Z_V21); // V4 <- (expand) V1(high)
z_vupllb(Z_V25, Z_V21); // V5 <- (expand) V1(low)
z_vstm(Z_V22, Z_V25, 0+dst_off, Rdst); // store next 32 bytes
src_off += min_vcnt;
dst_off += min_vcnt*2;
} else {
restore_inputs = true;
z_lgfi(Rix, len>>log_min_vcnt);
bind(VectorLoop);
z_vlm(Z_V20, Z_V21, 0, Rsrc); // get next 32 characters (single-byte)
add2reg(Rsrc, min_vcnt);
z_vuplhb(Z_V22, Z_V20); // V2 <- (expand) V0(high)
z_vupllb(Z_V23, Z_V20); // V3 <- (expand) V0(low)
z_vuplhb(Z_V24, Z_V21); // V4 <- (expand) V1(high)
z_vupllb(Z_V25, Z_V21); // V5 <- (expand) V1(low)
z_vstm(Z_V22, Z_V25, 0, Rdst); // store next 32 bytes
add2reg(Rdst, min_vcnt*2);
z_brct(Rix, VectorLoop);
}
}
if (((len-nprocessed) >= 16) && VM_Version::has_VectorFacility()) {
const int min_vcnt = 16; // Minimum #characters required to use vector instructions.
// Otherwise just do nothing in vector mode.
// Must be multiple of vector register length (16 bytes = 128 bits).
const int log_min_vcnt = exact_log2(min_vcnt);
const int iterations = (len - nprocessed) >> log_min_vcnt;
nprocessed += iterations << log_min_vcnt;
assert(iterations == 1, "must be!");
z_vl(Z_V20, 0+src_off, Z_R0, Rsrc); // get next 16 characters (single-byte)
z_vuplhb(Z_V22, Z_V20); // V2 <- (expand) V0(high)
z_vupllb(Z_V23, Z_V20); // V3 <- (expand) V0(low)
z_vstm(Z_V22, Z_V23, 0+dst_off, Rdst); // store next 32 bytes
src_off += min_vcnt;
dst_off += min_vcnt*2;
}
if ((len-nprocessed) > 8) {
const int min_cnt = 8; // Minimum #characters required to use unrolled scalar loop.
// Otherwise just do nothing in unrolled scalar mode.
// Must be multiple of 8.
const int log_min_cnt = exact_log2(min_cnt);
const int iterations = (len - nprocessed) >> log_min_cnt;
nprocessed += iterations << log_min_cnt;
//---< avoid loop overhead/ptr increment for small # iterations >---
if (iterations <= 2) {
clear_reg(Z_R0);
clear_reg(Z_R1);
workreg_clear = true;
z_icmh(Z_R0, 5, 0+src_off, Rsrc);
z_icmh(Z_R1, 5, 4+src_off, Rsrc);
z_icm(Z_R0, 5, 2+src_off, Rsrc);
z_icm(Z_R1, 5, 6+src_off, Rsrc);
z_stmg(Z_R0, Z_R1, 0+dst_off, Rdst);
src_off += min_cnt;
dst_off += min_cnt*2;
}
if (iterations == 2) {
z_icmh(Z_R0, 5, 0+src_off, Rsrc);
z_icmh(Z_R1, 5, 4+src_off, Rsrc);
z_icm(Z_R0, 5, 2+src_off, Rsrc);
z_icm(Z_R1, 5, 6+src_off, Rsrc);
z_stmg(Z_R0, Z_R1, 0+dst_off, Rdst);
src_off += min_cnt;
dst_off += min_cnt*2;
}
if (iterations > 2) {
Label UnrolledLoop;
restore_inputs = true;
clear_reg(Z_R0);
clear_reg(Z_R1);
workreg_clear = true;
z_lgfi(Rix, iterations);
bind(UnrolledLoop);
z_icmh(Z_R0, 5, 0, Rsrc);
z_icmh(Z_R1, 5, 4, Rsrc);
z_icm(Z_R0, 5, 2, Rsrc);
z_icm(Z_R1, 5, 6, Rsrc);
add2reg(Rsrc, min_cnt);
z_stmg(Z_R0, Z_R1, 0, Rdst);
add2reg(Rdst, min_cnt*2);
z_brct(Rix, UnrolledLoop);
}
}
if ((len-nprocessed) > 0) {
switch (len-nprocessed) {
case 8:
if (!workreg_clear) {
clear_reg(Z_R0);
clear_reg(Z_R1);
}
z_icmh(Z_R0, 5, 0+src_off, Rsrc);
z_icmh(Z_R1, 5, 4+src_off, Rsrc);
z_icm(Z_R0, 5, 2+src_off, Rsrc);
z_icm(Z_R1, 5, 6+src_off, Rsrc);
z_stmg(Z_R0, Z_R1, 0+dst_off, Rdst);
break;
case 7:
if (!workreg_clear) {
clear_reg(Z_R0);
clear_reg(Z_R1);
}
clear_reg(Rix);
z_icm(Z_R0, 5, 0+src_off, Rsrc);
z_icm(Z_R1, 5, 2+src_off, Rsrc);
z_icm(Rix, 5, 4+src_off, Rsrc);
z_stm(Z_R0, Z_R1, 0+dst_off, Rdst);
z_llc(Z_R0, 6+src_off, Z_R0, Rsrc);
z_st(Rix, 8+dst_off, Z_R0, Rdst);
z_sth(Z_R0, 12+dst_off, Z_R0, Rdst);
break;
case 6:
if (!workreg_clear) {
clear_reg(Z_R0);
clear_reg(Z_R1);
}
clear_reg(Rix);
z_icm(Z_R0, 5, 0+src_off, Rsrc);
z_icm(Z_R1, 5, 2+src_off, Rsrc);
z_icm(Rix, 5, 4+src_off, Rsrc);
z_stm(Z_R0, Z_R1, 0+dst_off, Rdst);
z_st(Rix, 8+dst_off, Z_R0, Rdst);
break;
case 5:
if (!workreg_clear) {
clear_reg(Z_R0);
clear_reg(Z_R1);
}
z_icm(Z_R0, 5, 0+src_off, Rsrc);
z_icm(Z_R1, 5, 2+src_off, Rsrc);
z_llc(Rix, 4+src_off, Z_R0, Rsrc);
z_stm(Z_R0, Z_R1, 0+dst_off, Rdst);
z_sth(Rix, 8+dst_off, Z_R0, Rdst);
break;
case 4:
if (!workreg_clear) {
clear_reg(Z_R0);
clear_reg(Z_R1);
}
z_icm(Z_R0, 5, 0+src_off, Rsrc);
z_icm(Z_R1, 5, 2+src_off, Rsrc);
z_stm(Z_R0, Z_R1, 0+dst_off, Rdst);
break;
case 3:
if (!workreg_clear) {
clear_reg(Z_R0);
}
z_llc(Z_R1, 2+src_off, Z_R0, Rsrc);
z_icm(Z_R0, 5, 0+src_off, Rsrc);
z_sth(Z_R1, 4+dst_off, Z_R0, Rdst);
z_st(Z_R0, 0+dst_off, Rdst);
break;
case 2:
z_llc(Z_R0, 0+src_off, Z_R0, Rsrc);
z_llc(Z_R1, 1+src_off, Z_R0, Rsrc);
z_sth(Z_R0, 0+dst_off, Z_R0, Rdst);
z_sth(Z_R1, 2+dst_off, Z_R0, Rdst);
break;
case 1:
z_llc(Z_R0, 0+src_off, Z_R0, Rsrc);
z_sth(Z_R0, 0+dst_off, Z_R0, Rdst);
break;
default:
guarantee(false, "Impossible");
break;
}
src_off += len-nprocessed;
dst_off += (len-nprocessed)*2;
nprocessed = len;
}
//---< restore modified input registers >---
if ((nprocessed > 0) && restore_inputs) {
z_agfi(Rsrc, -(nprocessed-src_off));
if (nprocessed < 1000000000) { // avoid int overflow
z_agfi(Rdst, -(nprocessed*2-dst_off));
} else {
z_agfi(Rdst, -(nprocessed-dst_off));
z_agfi(Rdst, -nprocessed);
}
}
BLOCK_COMMENT("} string_inflate_const");
return offset() - block_start;
}
// Kills src.
unsigned int MacroAssembler::has_negatives(Register result, Register src, Register cnt,
Register odd_reg, Register even_reg, Register tmp) {
int block_start = offset();
Label Lloop1, Lloop2, Lslow, Lnotfound, Ldone;
const Register addr = src, mask = tmp;
BLOCK_COMMENT("has_negatives {");
z_llgfr(Z_R1, cnt); // Number of bytes to read. (Must be a positive simm32.)
z_llilf(mask, 0x80808080);
z_lhi(result, 1); // Assume true.
// Last possible addr for fast loop.
z_lay(odd_reg, -16, Z_R1, src);
z_chi(cnt, 16);
z_brl(Lslow);
// ind1: index, even_reg: index increment, odd_reg: index limit
z_iihf(mask, 0x80808080);
z_lghi(even_reg, 16);
bind(Lloop1); // 16 bytes per iteration.
z_lg(Z_R0, Address(addr));
z_lg(Z_R1, Address(addr, 8));
z_ogr(Z_R0, Z_R1);
z_ngr(Z_R0, mask);
z_brne(Ldone); // If found return 1.
z_brxlg(addr, even_reg, Lloop1);
bind(Lslow);
z_aghi(odd_reg, 16-1); // Last possible addr for slow loop.
z_lghi(even_reg, 1);
z_cgr(addr, odd_reg);
z_brh(Lnotfound);
bind(Lloop2); // 1 byte per iteration.
z_cli(Address(addr), 0x80);
z_brnl(Ldone); // If found return 1.
z_brxlg(addr, even_reg, Lloop2);
bind(Lnotfound);
z_lhi(result, 0);
bind(Ldone);
BLOCK_COMMENT("} has_negatives");
return offset() - block_start;
}
// kill: cnt1, cnt2, odd_reg, even_reg; early clobber: result
unsigned int MacroAssembler::string_compare(Register str1, Register str2,
Register cnt1, Register cnt2,
Register odd_reg, Register even_reg, Register result, int ae) {
int block_start = offset();
assert_different_registers(str1, cnt1, cnt2, odd_reg, even_reg, result);
assert_different_registers(str2, cnt1, cnt2, odd_reg, even_reg, result);
// If strings are equal up to min length, return the length difference.
const Register diff = result, // Pre-set result with length difference.
min = cnt1, // min number of bytes
tmp = cnt2;
// Note: Making use of the fact that compareTo(a, b) == -compareTo(b, a)
// we interchange str1 and str2 in the UL case and negate the result.
// Like this, str1 is always latin1 encoded, except for the UU case.
// In addition, we need 0 (or sign which is 0) extend when using 64 bit register.
const bool used_as_LU = (ae == StrIntrinsicNode::LU || ae == StrIntrinsicNode::UL);
BLOCK_COMMENT("string_compare {");
if (used_as_LU) {
z_srl(cnt2, 1);
}
// See if the lengths are different, and calculate min in cnt1.
// Save diff in case we need it for a tie-breaker.
// diff = cnt1 - cnt2
if (VM_Version::has_DistinctOpnds()) {
z_srk(diff, cnt1, cnt2);
} else {
z_lr(diff, cnt1);
z_sr(diff, cnt2);
}
if (str1 != str2) {
if (VM_Version::has_LoadStoreConditional()) {
z_locr(min, cnt2, Assembler::bcondHigh);
} else {
Label Lskip;
z_brl(Lskip); // min ok if cnt1 < cnt2
z_lr(min, cnt2); // min = cnt2
bind(Lskip);
}
}
if (ae == StrIntrinsicNode::UU) {
z_sra(diff, 1);
}
if (str1 != str2) {
Label Ldone;
if (used_as_LU) {
// Loop which searches the first difference character by character.
Label Lloop;
const Register ind1 = Z_R1,
ind2 = min;
int stride1 = 1, stride2 = 2; // See comment above.
// ind1: index, even_reg: index increment, odd_reg: index limit
z_llilf(ind1, (unsigned int)(-stride1));
z_lhi(even_reg, stride1);
add2reg(odd_reg, -stride1, min);
clear_reg(ind2); // kills min
bind(Lloop);
z_brxh(ind1, even_reg, Ldone);
z_llc(tmp, Address(str1, ind1));
z_llh(Z_R0, Address(str2, ind2));
z_ahi(ind2, stride2);
z_sr(tmp, Z_R0);
z_bre(Lloop);
z_lr(result, tmp);
} else {
// Use clcle in fast loop (only for same encoding).
z_lgr(Z_R0, str1);
z_lgr(even_reg, str2);
z_llgfr(Z_R1, min);
z_llgfr(odd_reg, min);
if (ae == StrIntrinsicNode::LL) {
compare_long_ext(Z_R0, even_reg, 0);
} else {
compare_long_uni(Z_R0, even_reg, 0);
}
z_bre(Ldone);
z_lgr(Z_R1, Z_R0);
if (ae == StrIntrinsicNode::LL) {
z_llc(Z_R0, Address(even_reg));
z_llc(result, Address(Z_R1));
} else {
z_llh(Z_R0, Address(even_reg));
z_llh(result, Address(Z_R1));
}
z_sr(result, Z_R0);
}
// Otherwise, return the difference between the first mismatched chars.
bind(Ldone);
}
if (ae == StrIntrinsicNode::UL) {
z_lcr(result, result); // Negate result (see note above).
}
BLOCK_COMMENT("} string_compare");
return offset() - block_start;
}
unsigned int MacroAssembler::array_equals(bool is_array_equ, Register ary1, Register ary2, Register limit,
Register odd_reg, Register even_reg, Register result, bool is_byte) {
int block_start = offset();
BLOCK_COMMENT("array_equals {");
assert_different_registers(ary1, limit, odd_reg, even_reg);
assert_different_registers(ary2, limit, odd_reg, even_reg);
Label Ldone, Ldone_true, Ldone_false, Lclcle, CLC_template;
int base_offset = 0;
if (ary1 != ary2) {
if (is_array_equ) {
base_offset = arrayOopDesc::base_offset_in_bytes(is_byte ? T_BYTE : T_CHAR);
// Return true if the same array.
compareU64_and_branch(ary1, ary2, Assembler::bcondEqual, Ldone_true);
// Return false if one of them is NULL.
compareU64_and_branch(ary1, (intptr_t)0, Assembler::bcondEqual, Ldone_false);
compareU64_and_branch(ary2, (intptr_t)0, Assembler::bcondEqual, Ldone_false);
// Load the lengths of arrays.
z_llgf(odd_reg, Address(ary1, arrayOopDesc::length_offset_in_bytes()));
// Return false if the two arrays are not equal length.
z_c(odd_reg, Address(ary2, arrayOopDesc::length_offset_in_bytes()));
z_brne(Ldone_false);
// string len in bytes (right operand)
if (!is_byte) {
z_chi(odd_reg, 128);
z_sll(odd_reg, 1); // preserves flags
z_brh(Lclcle);
} else {
compareU32_and_branch(odd_reg, (intptr_t)256, Assembler::bcondHigh, Lclcle);
}
} else {
z_llgfr(odd_reg, limit); // Need to zero-extend prior to using the value.
compareU32_and_branch(limit, (intptr_t)256, Assembler::bcondHigh, Lclcle);
}
// Use clc instruction for up to 256 bytes.
{
Register str1_reg = ary1,
str2_reg = ary2;
if (is_array_equ) {
str1_reg = Z_R1;
str2_reg = even_reg;
add2reg(str1_reg, base_offset, ary1); // string addr (left operand)
add2reg(str2_reg, base_offset, ary2); // string addr (right operand)
}
z_ahi(odd_reg, -1); // Clc uses decremented limit. Also compare result to 0.
z_brl(Ldone_true);
// Note: We could jump to the template if equal.
assert(VM_Version::has_ExecuteExtensions(), "unsupported hardware");
z_exrl(odd_reg, CLC_template);
z_bre(Ldone_true);
// fall through
bind(Ldone_false);
clear_reg(result);
z_bru(Ldone);
bind(CLC_template);
z_clc(0, 0, str1_reg, 0, str2_reg);
}
// Use clcle instruction.
{
bind(Lclcle);
add2reg(even_reg, base_offset, ary2); // string addr (right operand)
add2reg(Z_R0, base_offset, ary1); // string addr (left operand)
z_lgr(Z_R1, odd_reg); // string len in bytes (left operand)
if (is_byte) {
compare_long_ext(Z_R0, even_reg, 0);
} else {
compare_long_uni(Z_R0, even_reg, 0);
}
z_lghi(result, 0); // Preserve flags.
z_brne(Ldone);
}
}
// fall through
bind(Ldone_true);
z_lghi(result, 1); // All characters are equal.
bind(Ldone);
BLOCK_COMMENT("} array_equals");
return offset() - block_start;
}
// kill: haycnt, needlecnt, odd_reg, even_reg; early clobber: result
unsigned int MacroAssembler::string_indexof(Register result, Register haystack, Register haycnt,
Register needle, Register needlecnt, int needlecntval,
Register odd_reg, Register even_reg, int ae) {
int block_start = offset();
// Ensure 0<needlecnt<=haycnt in ideal graph as prerequisite!
assert(ae != StrIntrinsicNode::LU, "Invalid encoding");
const int h_csize = (ae == StrIntrinsicNode::LL) ? 1 : 2;
const int n_csize = (ae == StrIntrinsicNode::UU) ? 2 : 1;
Label L_needle1, L_Found, L_NotFound;
BLOCK_COMMENT("string_indexof {");
if (needle == haystack) {
z_lhi(result, 0);
} else {
// Load first character of needle (R0 used by search_string instructions).
if (n_csize == 2) { z_llgh(Z_R0, Address(needle)); } else { z_llgc(Z_R0, Address(needle)); }
// Compute last haystack addr to use if no match gets found.
if (needlecnt != noreg) { // variable needlecnt
z_ahi(needlecnt, -1); // Remaining characters after first one.
z_sr(haycnt, needlecnt); // Compute index succeeding last element to compare.
if (n_csize == 2) { z_sll(needlecnt, 1); } // In bytes.
} else { // constant needlecnt
assert((needlecntval & 0x7fff) == needlecntval, "must be positive simm16 immediate");
// Compute index succeeding last element to compare.
if (needlecntval != 1) { z_ahi(haycnt, 1 - needlecntval); }
}
z_llgfr(haycnt, haycnt); // Clear high half.
z_lgr(result, haystack); // Final result will be computed from needle start pointer.
if (h_csize == 2) { z_sll(haycnt, 1); } // Scale to number of bytes.
z_agr(haycnt, haystack); // Point to address succeeding last element (haystack+scale*(haycnt-needlecnt+1)).
if (h_csize != n_csize) {
assert(ae == StrIntrinsicNode::UL, "Invalid encoding");
if (needlecnt != noreg || needlecntval != 1) {
if (needlecnt != noreg) {
compare32_and_branch(needlecnt, (intptr_t)0, Assembler::bcondEqual, L_needle1);
}
// Main Loop: UL version (now we have at least 2 characters).
Label L_OuterLoop, L_InnerLoop, L_Skip;
bind(L_OuterLoop); // Search for 1st 2 characters.
z_lgr(Z_R1, haycnt);
MacroAssembler::search_string_uni(Z_R1, result);
z_brc(Assembler::bcondNotFound, L_NotFound);
z_lgr(result, Z_R1);
z_lghi(Z_R1, n_csize);
z_lghi(even_reg, h_csize);
bind(L_InnerLoop);
z_llgc(odd_reg, Address(needle, Z_R1));
z_ch(odd_reg, Address(result, even_reg));
z_brne(L_Skip);
if (needlecnt != noreg) { z_cr(Z_R1, needlecnt); } else { z_chi(Z_R1, needlecntval - 1); }
z_brnl(L_Found);
z_aghi(Z_R1, n_csize);
z_aghi(even_reg, h_csize);
z_bru(L_InnerLoop);
bind(L_Skip);
z_aghi(result, h_csize); // This is the new address we want to use for comparing.
z_bru(L_OuterLoop);
}
} else {
const intptr_t needle_bytes = (n_csize == 2) ? ((needlecntval - 1) << 1) : (needlecntval - 1);
Label L_clcle;
if (needlecnt != noreg || (needlecntval != 1 && needle_bytes <= 256)) {
if (needlecnt != noreg) {
compare32_and_branch(needlecnt, 256, Assembler::bcondHigh, L_clcle);
z_ahi(needlecnt, -1); // remaining bytes -1 (for CLC)
z_brl(L_needle1);
}
// Main Loop: clc version (now we have at least 2 characters).
Label L_OuterLoop, CLC_template;
bind(L_OuterLoop); // Search for 1st 2 characters.
z_lgr(Z_R1, haycnt);
if (h_csize == 1) {
MacroAssembler::search_string(Z_R1, result);
} else {
MacroAssembler::search_string_uni(Z_R1, result);
}
z_brc(Assembler::bcondNotFound, L_NotFound);
z_lgr(result, Z_R1);
if (needlecnt != noreg) {
assert(VM_Version::has_ExecuteExtensions(), "unsupported hardware");
z_exrl(needlecnt, CLC_template);
} else {
z_clc(h_csize, needle_bytes -1, Z_R1, n_csize, needle);
}
z_bre(L_Found);
z_aghi(result, h_csize); // This is the new address we want to use for comparing.
z_bru(L_OuterLoop);
if (needlecnt != noreg) {
bind(CLC_template);
z_clc(h_csize, 0, Z_R1, n_csize, needle);
}
}
if (needlecnt != noreg || needle_bytes > 256) {
bind(L_clcle);
// Main Loop: clcle version (now we have at least 256 bytes).
Label L_OuterLoop, CLC_template;
bind(L_OuterLoop); // Search for 1st 2 characters.
z_lgr(Z_R1, haycnt);
if (h_csize == 1) {
MacroAssembler::search_string(Z_R1, result);
} else {
MacroAssembler::search_string_uni(Z_R1, result);
}
z_brc(Assembler::bcondNotFound, L_NotFound);
add2reg(Z_R0, n_csize, needle);
add2reg(even_reg, h_csize, Z_R1);
z_lgr(result, Z_R1);
if (needlecnt != noreg) {
z_llgfr(Z_R1, needlecnt); // needle len in bytes (left operand)
z_llgfr(odd_reg, needlecnt);
} else {
load_const_optimized(Z_R1, needle_bytes);
if (Immediate::is_simm16(needle_bytes)) { z_lghi(odd_reg, needle_bytes); } else { z_lgr(odd_reg, Z_R1); }
}
if (h_csize == 1) {
compare_long_ext(Z_R0, even_reg, 0);
} else {
compare_long_uni(Z_R0, even_reg, 0);
}
z_bre(L_Found);
if (n_csize == 2) { z_llgh(Z_R0, Address(needle)); } else { z_llgc(Z_R0, Address(needle)); } // Reload.
z_aghi(result, h_csize); // This is the new address we want to use for comparing.
z_bru(L_OuterLoop);
}
}
if (needlecnt != noreg || needlecntval == 1) {
bind(L_needle1);
// Single needle character version.
if (h_csize == 1) {
MacroAssembler::search_string(haycnt, result);
} else {
MacroAssembler::search_string_uni(haycnt, result);
}
z_lgr(result, haycnt);
z_brc(Assembler::bcondFound, L_Found);
}
bind(L_NotFound);
add2reg(result, -1, haystack); // Return -1.
bind(L_Found); // Return index (or -1 in fallthrough case).
z_sgr(result, haystack);
if (h_csize == 2) { z_srag(result, result, exact_log2(sizeof(jchar))); }
}
BLOCK_COMMENT("} string_indexof");
return offset() - block_start;
}
// early clobber: result
unsigned int MacroAssembler::string_indexof_char(Register result, Register haystack, Register haycnt,
Register needle, jchar needleChar, Register odd_reg, Register even_reg, bool is_byte) {
int block_start = offset();
BLOCK_COMMENT("string_indexof_char {");
if (needle == haystack) {
z_lhi(result, 0);
} else {
Label Ldone;
z_llgfr(odd_reg, haycnt); // Preset loop ctr/searchrange end.
if (needle == noreg) {
load_const_optimized(Z_R0, (unsigned long)needleChar);
} else {
if (is_byte) {
z_llgcr(Z_R0, needle); // First (and only) needle char.
} else {
z_llghr(Z_R0, needle); // First (and only) needle char.
}
}
if (!is_byte) {
z_agr(odd_reg, odd_reg); // Calc #bytes to be processed with SRSTU.
}
z_lgr(even_reg, haystack); // haystack addr
z_agr(odd_reg, haystack); // First char after range end.
z_lghi(result, -1);
if (is_byte) {
MacroAssembler::search_string(odd_reg, even_reg);
} else {
MacroAssembler::search_string_uni(odd_reg, even_reg);
}
z_brc(Assembler::bcondNotFound, Ldone);
if (is_byte) {
if (VM_Version::has_DistinctOpnds()) {
z_sgrk(result, odd_reg, haystack);
} else {
z_sgr(odd_reg, haystack);
z_lgr(result, odd_reg);
}
} else {
z_slgr(odd_reg, haystack);
z_srlg(result, odd_reg, exact_log2(sizeof(jchar)));
}
bind(Ldone);
}
BLOCK_COMMENT("} string_indexof_char");
return offset() - block_start;
}
//-------------------------------------------------
// Constants (scalar and oop) in constant pool
//-------------------------------------------------
// Add a non-relocated constant to the CP.
int MacroAssembler::store_const_in_toc(AddressLiteral& val) {
long value = val.value();
address tocPos = long_constant(value);
if (tocPos != NULL) {
int tocOffset = (int)(tocPos - code()->consts()->start());
return tocOffset;
}
// Address_constant returned NULL, so no constant entry has been created.
// In that case, we return a "fatal" offset, just in case that subsequently
// generated access code is executed.
return -1;
}
// Returns the TOC offset where the address is stored.
// Add a relocated constant to the CP.
int MacroAssembler::store_oop_in_toc(AddressLiteral& oop) {
// Use RelocationHolder::none for the constant pool entry.
// Otherwise we will end up with a failing NativeCall::verify(x),
// where x is the address of the constant pool entry.
address tocPos = address_constant((address)oop.value(), RelocationHolder::none);
if (tocPos != NULL) {
int tocOffset = (int)(tocPos - code()->consts()->start());
RelocationHolder rsp = oop.rspec();
Relocation *rel = rsp.reloc();
// Store toc_offset in relocation, used by call_far_patchable.
if ((relocInfo::relocType)rel->type() == relocInfo::runtime_call_w_cp_type) {
((runtime_call_w_cp_Relocation *)(rel))->set_constant_pool_offset(tocOffset);
}
// Relocate at the load's pc.
relocate(rsp);
return tocOffset;
}
// Address_constant returned NULL, so no constant entry has been created
// in that case, we return a "fatal" offset, just in case that subsequently
// generated access code is executed.
return -1;
}
bool MacroAssembler::load_const_from_toc(Register dst, AddressLiteral& a, Register Rtoc) {
int tocOffset = store_const_in_toc(a);
if (tocOffset == -1) return false;
address tocPos = tocOffset + code()->consts()->start();
assert((address)code()->consts()->start() != NULL, "Please add CP address");
relocate(a.rspec());
load_long_pcrelative(dst, tocPos);
return true;
}
bool MacroAssembler::load_oop_from_toc(Register dst, AddressLiteral& a, Register Rtoc) {
int tocOffset = store_oop_in_toc(a);
if (tocOffset == -1) return false;
address tocPos = tocOffset + code()->consts()->start();
assert((address)code()->consts()->start() != NULL, "Please add CP address");
load_addr_pcrelative(dst, tocPos);
return true;
}
// If the instruction sequence at the given pc is a load_const_from_toc
// sequence, return the value currently stored at the referenced position
// in the TOC.
intptr_t MacroAssembler::get_const_from_toc(address pc) {
assert(is_load_const_from_toc(pc), "must be load_const_from_pool");
long offset = get_load_const_from_toc_offset(pc);
address dataLoc = NULL;
if (is_load_const_from_toc_pcrelative(pc)) {
dataLoc = pc + offset;
} else {
CodeBlob* cb = CodeCache::find_blob_unsafe(pc); // Else we get assertion if nmethod is zombie.
assert(cb && cb->is_nmethod(), "sanity");
nmethod* nm = (nmethod*)cb;
dataLoc = nm->ctable_begin() + offset;
}
return *(intptr_t *)dataLoc;
}
// If the instruction sequence at the given pc is a load_const_from_toc
// sequence, copy the passed-in new_data value into the referenced
// position in the TOC.
void MacroAssembler::set_const_in_toc(address pc, unsigned long new_data, CodeBlob *cb) {
assert(is_load_const_from_toc(pc), "must be load_const_from_pool");
long offset = MacroAssembler::get_load_const_from_toc_offset(pc);
address dataLoc = NULL;
if (is_load_const_from_toc_pcrelative(pc)) {
dataLoc = pc+offset;
} else {
nmethod* nm = CodeCache::find_nmethod(pc);
assert((cb == NULL) || (nm == (nmethod*)cb), "instruction address should be in CodeBlob");
dataLoc = nm->ctable_begin() + offset;
}
if (*(unsigned long *)dataLoc != new_data) { // Prevent cache invalidation: update only if necessary.
*(unsigned long *)dataLoc = new_data;
}
}
// Dynamic TOC. Getter must only be called if "a" is a load_const_from_toc
// site. Verify by calling is_load_const_from_toc() before!!
// Offset is +/- 2**32 -> use long.
long MacroAssembler::get_load_const_from_toc_offset(address a) {
assert(is_load_const_from_toc_pcrelative(a), "expected pc relative load");
// expected code sequence:
// z_lgrl(t, simm32); len = 6
unsigned long inst;
unsigned int len = get_instruction(a, &inst);
return get_pcrel_offset(inst);
}
//**********************************************************************************
// inspection of generated instruction sequences for a particular pattern
//**********************************************************************************
bool MacroAssembler::is_load_const_from_toc_pcrelative(address a) {
#ifdef ASSERT
unsigned long inst;
unsigned int len = get_instruction(a+2, &inst);
if ((len == 6) && is_load_pcrelative_long(a) && is_call_pcrelative_long(inst)) {
const int range = 128;
Assembler::dump_code_range(tty, a, range, "instr(a) == z_lgrl && instr(a+2) == z_brasl");
VM_Version::z_SIGSEGV();
}
#endif
// expected code sequence:
// z_lgrl(t, relAddr32); len = 6
//TODO: verify accessed data is in CP, if possible.
return is_load_pcrelative_long(a); // TODO: might be too general. Currently, only lgrl is used.
}
bool MacroAssembler::is_load_const_from_toc_call(address a) {
return is_load_const_from_toc(a) && is_call_byregister(a + load_const_from_toc_size());
}
bool MacroAssembler::is_load_const_call(address a) {
return is_load_const(a) && is_call_byregister(a + load_const_size());
}
//-------------------------------------------------
// Emitters for some really CICS instructions
//-------------------------------------------------
void MacroAssembler::move_long_ext(Register dst, Register src, unsigned int pad) {
assert(dst->encoding()%2==0, "must be an even/odd register pair");
assert(src->encoding()%2==0, "must be an even/odd register pair");
assert(pad<256, "must be a padding BYTE");
Label retry;
bind(retry);
Assembler::z_mvcle(dst, src, pad);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::compare_long_ext(Register left, Register right, unsigned int pad) {
assert(left->encoding() % 2 == 0, "must be an even/odd register pair");
assert(right->encoding() % 2 == 0, "must be an even/odd register pair");
assert(pad<256, "must be a padding BYTE");
Label retry;
bind(retry);
Assembler::z_clcle(left, right, pad, Z_R0);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::compare_long_uni(Register left, Register right, unsigned int pad) {
assert(left->encoding() % 2 == 0, "must be an even/odd register pair");
assert(right->encoding() % 2 == 0, "must be an even/odd register pair");
assert(pad<=0xfff, "must be a padding HALFWORD");
assert(VM_Version::has_ETF2(), "instruction must be available");
Label retry;
bind(retry);
Assembler::z_clclu(left, right, pad, Z_R0);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::search_string(Register end, Register start) {
assert(end->encoding() != 0, "end address must not be in R0");
assert(start->encoding() != 0, "start address must not be in R0");
Label retry;
bind(retry);
Assembler::z_srst(end, start);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::search_string_uni(Register end, Register start) {
assert(end->encoding() != 0, "end address must not be in R0");
assert(start->encoding() != 0, "start address must not be in R0");
assert(VM_Version::has_ETF3(), "instruction must be available");
Label retry;
bind(retry);
Assembler::z_srstu(end, start);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::kmac(Register srcBuff) {
assert(srcBuff->encoding() != 0, "src buffer address can't be in Z_R0");
assert(srcBuff->encoding() % 2 == 0, "src buffer/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_kmac(Z_R0, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::kimd(Register srcBuff) {
assert(srcBuff->encoding() != 0, "src buffer address can't be in Z_R0");
assert(srcBuff->encoding() % 2 == 0, "src buffer/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_kimd(Z_R0, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::klmd(Register srcBuff) {
assert(srcBuff->encoding() != 0, "src buffer address can't be in Z_R0");
assert(srcBuff->encoding() % 2 == 0, "src buffer/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_klmd(Z_R0, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::km(Register dstBuff, Register srcBuff) {
// DstBuff and srcBuff are allowed to be the same register (encryption in-place).
// DstBuff and srcBuff storage must not overlap destructively, and neither must overlap the parameter block.
assert(srcBuff->encoding() != 0, "src buffer address can't be in Z_R0");
assert(dstBuff->encoding() % 2 == 0, "dst buffer addr must be an even register");
assert(srcBuff->encoding() % 2 == 0, "src buffer addr/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_km(dstBuff, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::kmc(Register dstBuff, Register srcBuff) {
// DstBuff and srcBuff are allowed to be the same register (encryption in-place).
// DstBuff and srcBuff storage must not overlap destructively, and neither must overlap the parameter block.
assert(srcBuff->encoding() != 0, "src buffer address can't be in Z_R0");
assert(dstBuff->encoding() % 2 == 0, "dst buffer addr must be an even register");
assert(srcBuff->encoding() % 2 == 0, "src buffer addr/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_kmc(dstBuff, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::cksm(Register crcBuff, Register srcBuff) {
assert(srcBuff->encoding() % 2 == 0, "src buffer addr/len must be an even/odd register pair");
Label retry;
bind(retry);
Assembler::z_cksm(crcBuff, srcBuff);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::translate_oo(Register r1, Register r2, uint m3) {
assert(r1->encoding() % 2 == 0, "dst addr/src len must be an even/odd register pair");
assert((m3 & 0b1110) == 0, "Unused mask bits must be zero");
Label retry;
bind(retry);
Assembler::z_troo(r1, r2, m3);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::translate_ot(Register r1, Register r2, uint m3) {
assert(r1->encoding() % 2 == 0, "dst addr/src len must be an even/odd register pair");
assert((m3 & 0b1110) == 0, "Unused mask bits must be zero");
Label retry;
bind(retry);
Assembler::z_trot(r1, r2, m3);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::translate_to(Register r1, Register r2, uint m3) {
assert(r1->encoding() % 2 == 0, "dst addr/src len must be an even/odd register pair");
assert((m3 & 0b1110) == 0, "Unused mask bits must be zero");
Label retry;
bind(retry);
Assembler::z_trto(r1, r2, m3);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::translate_tt(Register r1, Register r2, uint m3) {
assert(r1->encoding() % 2 == 0, "dst addr/src len must be an even/odd register pair");
assert((m3 & 0b1110) == 0, "Unused mask bits must be zero");
Label retry;
bind(retry);
Assembler::z_trtt(r1, r2, m3);
Assembler::z_brc(Assembler::bcondOverflow /* CC==3 (iterate) */, retry);
}
void MacroAssembler::generate_type_profiling(const Register Rdata,
const Register Rreceiver_klass,
const Register Rwanted_receiver_klass,
const Register Rmatching_row,
bool is_virtual_call) {
const int row_size = in_bytes(ReceiverTypeData::receiver_offset(1)) -
in_bytes(ReceiverTypeData::receiver_offset(0));
const int num_rows = ReceiverTypeData::row_limit();
NearLabel found_free_row;
NearLabel do_increment;
NearLabel found_no_slot;
BLOCK_COMMENT("type profiling {");
// search for:
// a) The type given in Rwanted_receiver_klass.
// b) The *first* empty row.
// First search for a) only, just running over b) with no regard.
// This is possible because
// wanted_receiver_class == receiver_class && wanted_receiver_class == 0
// is never true (receiver_class can't be zero).
for (int row_num = 0; row_num < num_rows; row_num++) {
// Row_offset should be a well-behaved positive number. The generated code relies
// on that wrt constant code size. Add2reg can handle all row_offset values, but
// will have to vary generated code size.
int row_offset = in_bytes(ReceiverTypeData::receiver_offset(row_num));
assert(Displacement::is_shortDisp(row_offset), "Limitation of generated code");
// Is Rwanted_receiver_klass in this row?
if (VM_Version::has_CompareBranch()) {
z_lg(Rwanted_receiver_klass, row_offset, Z_R0, Rdata);
// Rmatching_row = Rdata + row_offset;
add2reg(Rmatching_row, row_offset, Rdata);
// if (*row_recv == (intptr_t) receiver_klass) goto fill_existing_slot;
compare64_and_branch(Rwanted_receiver_klass, Rreceiver_klass, Assembler::bcondEqual, do_increment);
} else {
add2reg(Rmatching_row, row_offset, Rdata);
z_cg(Rreceiver_klass, row_offset, Z_R0, Rdata);
z_bre(do_increment);
}
}
// Now that we did not find a match, let's search for b).
// We could save the first calculation of Rmatching_row if we woud search for a) in reverse order.
// We would then end up here with Rmatching_row containing the value for row_num == 0.
// We would not see much benefit, if any at all, because the CPU can schedule
// two instructions together with a branch anyway.
for (int row_num = 0; row_num < num_rows; row_num++) {
int row_offset = in_bytes(ReceiverTypeData::receiver_offset(row_num));
// Has this row a zero receiver_klass, i.e. is it empty?
if (VM_Version::has_CompareBranch()) {
z_lg(Rwanted_receiver_klass, row_offset, Z_R0, Rdata);
// Rmatching_row = Rdata + row_offset
add2reg(Rmatching_row, row_offset, Rdata);
// if (*row_recv == (intptr_t) 0) goto found_free_row
compare64_and_branch(Rwanted_receiver_klass, (intptr_t)0, Assembler::bcondEqual, found_free_row);
} else {
add2reg(Rmatching_row, row_offset, Rdata);
load_and_test_long(Rwanted_receiver_klass, Address(Rdata, row_offset));
z_bre(found_free_row); // zero -> Found a free row.
}
}
// No match, no empty row found.
// Increment total counter to indicate polymorphic case.
if (is_virtual_call) {
add2mem_64(Address(Rdata, CounterData::count_offset()), 1, Rmatching_row);
}
z_bru(found_no_slot);
// Here we found an empty row, but we have not found Rwanted_receiver_klass.
// Rmatching_row holds the address to the first empty row.
bind(found_free_row);
// Store receiver_klass into empty slot.
z_stg(Rreceiver_klass, 0, Z_R0, Rmatching_row);
// Increment the counter of Rmatching_row.
bind(do_increment);
ByteSize counter_offset = ReceiverTypeData::receiver_count_offset(0) - ReceiverTypeData::receiver_offset(0);
add2mem_64(Address(Rmatching_row, counter_offset), 1, Rdata);
bind(found_no_slot);
BLOCK_COMMENT("} type profiling");
}
//---------------------------------------
// Helpers for Intrinsic Emitters
//---------------------------------------
/**
* uint32_t crc;
* timesXtoThe32[crc & 0xFF] ^ (crc >> 8);
*/
void MacroAssembler::fold_byte_crc32(Register crc, Register val, Register table, Register tmp) {
assert_different_registers(crc, table, tmp);
assert_different_registers(val, table);
if (crc == val) { // Must rotate first to use the unmodified value.
rotate_then_insert(tmp, val, 56-2, 63-2, 2, true); // Insert byte 7 of val, shifted left by 2, into byte 6..7 of tmp, clear the rest.
z_srl(crc, 8); // Unsigned shift, clear leftmost 8 bits.
} else {
z_srl(crc, 8); // Unsigned shift, clear leftmost 8 bits.
rotate_then_insert(tmp, val, 56-2, 63-2, 2, true); // Insert byte 7 of val, shifted left by 2, into byte 6..7 of tmp, clear the rest.
}
z_x(crc, Address(table, tmp, 0));
}
/**
* uint32_t crc;
* timesXtoThe32[crc & 0xFF] ^ (crc >> 8);
*/
void MacroAssembler::fold_8bit_crc32(Register crc, Register table, Register tmp) {
fold_byte_crc32(crc, crc, table, tmp);
}
/**
* Emits code to update CRC-32 with a byte value according to constants in table.
*
* @param [in,out]crc Register containing the crc.
* @param [in]val Register containing the byte to fold into the CRC.
* @param [in]table Register containing the table of crc constants.
*
* uint32_t crc;
* val = crc_table[(val ^ crc) & 0xFF];
* crc = val ^ (crc >> 8);
*/
void MacroAssembler::update_byte_crc32(Register crc, Register val, Register table) {
z_xr(val, crc);
fold_byte_crc32(crc, val, table, val);
}
/**
* @param crc register containing existing CRC (32-bit)
* @param buf register pointing to input byte buffer (byte*)
* @param len register containing number of bytes
* @param table register pointing to CRC table
*/
void MacroAssembler::update_byteLoop_crc32(Register crc, Register buf, Register len, Register table, Register data) {
assert_different_registers(crc, buf, len, table, data);
Label L_mainLoop, L_done;
const int mainLoop_stepping = 1;
// Process all bytes in a single-byte loop.
z_ltr(len, len);
z_brnh(L_done);
bind(L_mainLoop);
z_llgc(data, Address(buf, (intptr_t)0));// Current byte of input buffer (zero extended). Avoids garbage in upper half of register.
add2reg(buf, mainLoop_stepping); // Advance buffer position.
update_byte_crc32(crc, data, table);
z_brct(len, L_mainLoop); // Iterate.
bind(L_done);
}
/**
* Emits code to update CRC-32 with a 4-byte value according to constants in table.
* Implementation according to jdk/src/share/native/java/util/zip/zlib-1.2.8/crc32.c.
*
*/
void MacroAssembler::update_1word_crc32(Register crc, Register buf, Register table, int bufDisp, int bufInc,
Register t0, Register t1, Register t2, Register t3) {
// This is what we implement (the DOBIG4 part):
//
// #define DOBIG4 c ^= *++buf4; \
// c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \
// crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24]
// #define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4
// Pre-calculate (constant) column offsets, use columns 4..7 for big-endian.
const int ix0 = 4*(4*CRC32_COLUMN_SIZE);
const int ix1 = 5*(4*CRC32_COLUMN_SIZE);
const int ix2 = 6*(4*CRC32_COLUMN_SIZE);
const int ix3 = 7*(4*CRC32_COLUMN_SIZE);
// XOR crc with next four bytes of buffer.
lgr_if_needed(t0, crc);
z_x(t0, Address(buf, bufDisp));
if (bufInc != 0) {
add2reg(buf, bufInc);
}
// Chop crc into 4 single-byte pieces, shifted left 2 bits, to form the table indices.
rotate_then_insert(t3, t0, 56-2, 63-2, 2, true); // ((c >> 0) & 0xff) << 2
rotate_then_insert(t2, t0, 56-2, 63-2, 2-8, true); // ((c >> 8) & 0xff) << 2
rotate_then_insert(t1, t0, 56-2, 63-2, 2-16, true); // ((c >> 16) & 0xff) << 2
rotate_then_insert(t0, t0, 56-2, 63-2, 2-24, true); // ((c >> 24) & 0xff) << 2
// XOR indexed table values to calculate updated crc.
z_ly(t2, Address(table, t2, (intptr_t)ix1));
z_ly(t0, Address(table, t0, (intptr_t)ix3));
z_xy(t2, Address(table, t3, (intptr_t)ix0));
z_xy(t0, Address(table, t1, (intptr_t)ix2));
z_xr(t0, t2); // Now t0 contains the updated CRC value.
lgr_if_needed(crc, t0);
}
/**
* @param crc register containing existing CRC (32-bit)
* @param buf register pointing to input byte buffer (byte*)
* @param len register containing number of bytes
* @param table register pointing to CRC table
*
* uses Z_R10..Z_R13 as work register. Must be saved/restored by caller!
*/
void MacroAssembler::kernel_crc32_1word(Register crc, Register buf, Register len, Register table,
Register t0, Register t1, Register t2, Register t3,
bool invertCRC) {
assert_different_registers(crc, buf, len, table);
Label L_mainLoop, L_tail;
Register data = t0;
Register ctr = Z_R0;
const int mainLoop_stepping = 4;
const int log_stepping = exact_log2(mainLoop_stepping);
// Don't test for len <= 0 here. This pathological case should not occur anyway.
// Optimizing for it by adding a test and a branch seems to be a waste of CPU cycles.
// The situation itself is detected and handled correctly by the conditional branches
// following aghi(len, -stepping) and aghi(len, +stepping).
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
// Check for short (<4 bytes) buffer.
z_srag(ctr, len, log_stepping);
z_brnh(L_tail);
z_lrvr(crc, crc); // Revert byte order because we are dealing with big-endian data.
rotate_then_insert(len, len, 64-log_stepping, 63, 0, true); // #bytes for tailLoop
BIND(L_mainLoop);
update_1word_crc32(crc, buf, table, 0, mainLoop_stepping, crc, t1, t2, t3);
z_brct(ctr, L_mainLoop); // Iterate.
z_lrvr(crc, crc); // Revert byte order back to original.
// Process last few (<8) bytes of buffer.
BIND(L_tail);
update_byteLoop_crc32(crc, buf, len, table, data);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
}
/**
* @param crc register containing existing CRC (32-bit)
* @param buf register pointing to input byte buffer (byte*)
* @param len register containing number of bytes
* @param table register pointing to CRC table
*/
void MacroAssembler::kernel_crc32_1byte(Register crc, Register buf, Register len, Register table,
Register t0, Register t1, Register t2, Register t3,
bool invertCRC) {
assert_different_registers(crc, buf, len, table);
Register data = t0;
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
update_byteLoop_crc32(crc, buf, len, table, data);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
}
void MacroAssembler::kernel_crc32_singleByte(Register crc, Register buf, Register len, Register table, Register tmp,
bool invertCRC) {
assert_different_registers(crc, buf, len, table, tmp);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
z_llgc(tmp, Address(buf, (intptr_t)0)); // Current byte of input buffer (zero extended). Avoids garbage in upper half of register.
update_byte_crc32(crc, tmp, table);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
}
void MacroAssembler::kernel_crc32_singleByteReg(Register crc, Register val, Register table,
bool invertCRC) {
assert_different_registers(crc, val, table);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
update_byte_crc32(crc, val, table);
if (invertCRC) {
not_(crc, noreg, false); // 1s complement of crc
}
}
//
// Code for BigInteger::multiplyToLen() intrinsic.
//
// dest_lo += src1 + src2
// dest_hi += carry1 + carry2
// Z_R7 is destroyed !
void MacroAssembler::add2_with_carry(Register dest_hi, Register dest_lo,
Register src1, Register src2) {
clear_reg(Z_R7);
z_algr(dest_lo, src1);
z_alcgr(dest_hi, Z_R7);
z_algr(dest_lo, src2);
z_alcgr(dest_hi, Z_R7);
}
// Multiply 64 bit by 64 bit first loop.
void MacroAssembler::multiply_64_x_64_loop(Register x, Register xstart,
Register x_xstart,
Register y, Register y_idx,
Register z,
Register carry,
Register product,
Register idx, Register kdx) {
// jlong carry, x[], y[], z[];
// for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx--, kdx--) {
// huge_128 product = y[idx] * x[xstart] + carry;
// z[kdx] = (jlong)product;
// carry = (jlong)(product >>> 64);
// }
// z[xstart] = carry;
Label L_first_loop, L_first_loop_exit;
Label L_one_x, L_one_y, L_multiply;
z_aghi(xstart, -1);
z_brl(L_one_x); // Special case: length of x is 1.
// Load next two integers of x.
z_sllg(Z_R1_scratch, xstart, LogBytesPerInt);
mem2reg_opt(x_xstart, Address(x, Z_R1_scratch, 0));
bind(L_first_loop);
z_aghi(idx, -1);
z_brl(L_first_loop_exit);
z_aghi(idx, -1);
z_brl(L_one_y);
// Load next two integers of y.
z_sllg(Z_R1_scratch, idx, LogBytesPerInt);
mem2reg_opt(y_idx, Address(y, Z_R1_scratch, 0));
bind(L_multiply);
Register multiplicand = product->successor();
Register product_low = multiplicand;
lgr_if_needed(multiplicand, x_xstart);
z_mlgr(product, y_idx); // multiplicand * y_idx -> product::multiplicand
clear_reg(Z_R7);
z_algr(product_low, carry); // Add carry to result.
z_alcgr(product, Z_R7); // Add carry of the last addition.
add2reg(kdx, -2);
// Store result.
z_sllg(Z_R7, kdx, LogBytesPerInt);
reg2mem_opt(product_low, Address(z, Z_R7, 0));
lgr_if_needed(carry, product);
z_bru(L_first_loop);
bind(L_one_y); // Load one 32 bit portion of y as (0,value).
clear_reg(y_idx);
mem2reg_opt(y_idx, Address(y, (intptr_t) 0), false);
z_bru(L_multiply);
bind(L_one_x); // Load one 32 bit portion of x as (0,value).
clear_reg(x_xstart);
mem2reg_opt(x_xstart, Address(x, (intptr_t) 0), false);
z_bru(L_first_loop);
bind(L_first_loop_exit);
}
// Multiply 64 bit by 64 bit and add 128 bit.
void MacroAssembler::multiply_add_128_x_128(Register x_xstart, Register y,
Register z,
Register yz_idx, Register idx,
Register carry, Register product,
int offset) {
// huge_128 product = (y[idx] * x_xstart) + z[kdx] + carry;
// z[kdx] = (jlong)product;
Register multiplicand = product->successor();
Register product_low = multiplicand;
z_sllg(Z_R7, idx, LogBytesPerInt);
mem2reg_opt(yz_idx, Address(y, Z_R7, offset));
lgr_if_needed(multiplicand, x_xstart);
z_mlgr(product, yz_idx); // multiplicand * yz_idx -> product::multiplicand
mem2reg_opt(yz_idx, Address(z, Z_R7, offset));
add2_with_carry(product, product_low, carry, yz_idx);
z_sllg(Z_R7, idx, LogBytesPerInt);
reg2mem_opt(product_low, Address(z, Z_R7, offset));
}
// Multiply 128 bit by 128 bit. Unrolled inner loop.
void MacroAssembler::multiply_128_x_128_loop(Register x_xstart,
Register y, Register z,
Register yz_idx, Register idx,
Register jdx,
Register carry, Register product,
Register carry2) {
// jlong carry, x[], y[], z[];
// int kdx = ystart+1;
// for (int idx=ystart-2; idx >= 0; idx -= 2) { // Third loop
// huge_128 product = (y[idx+1] * x_xstart) + z[kdx+idx+1] + carry;
// z[kdx+idx+1] = (jlong)product;
// jlong carry2 = (jlong)(product >>> 64);
// product = (y[idx] * x_xstart) + z[kdx+idx] + carry2;
// z[kdx+idx] = (jlong)product;
// carry = (jlong)(product >>> 64);
// }
// idx += 2;
// if (idx > 0) {
// product = (y[idx] * x_xstart) + z[kdx+idx] + carry;
// z[kdx+idx] = (jlong)product;
// carry = (jlong)(product >>> 64);
// }
Label L_third_loop, L_third_loop_exit, L_post_third_loop_done;
// scale the index
lgr_if_needed(jdx, idx);
and_imm(jdx, 0xfffffffffffffffcL);
rshift(jdx, 2);
bind(L_third_loop);
z_aghi(jdx, -1);
z_brl(L_third_loop_exit);
add2reg(idx, -4);
multiply_add_128_x_128(x_xstart, y, z, yz_idx, idx, carry, product, 8);
lgr_if_needed(carry2, product);
multiply_add_128_x_128(x_xstart, y, z, yz_idx, idx, carry2, product, 0);
lgr_if_needed(carry, product);
z_bru(L_third_loop);
bind(L_third_loop_exit); // Handle any left-over operand parts.
and_imm(idx, 0x3);
z_brz(L_post_third_loop_done);
Label L_check_1;
z_aghi(idx, -2);
z_brl(L_check_1);
multiply_add_128_x_128(x_xstart, y, z, yz_idx, idx, carry, product, 0);
lgr_if_needed(carry, product);
bind(L_check_1);
add2reg(idx, 0x2);
and_imm(idx, 0x1);
z_aghi(idx, -1);
z_brl(L_post_third_loop_done);
Register multiplicand = product->successor();
Register product_low = multiplicand;
z_sllg(Z_R7, idx, LogBytesPerInt);
clear_reg(yz_idx);
mem2reg_opt(yz_idx, Address(y, Z_R7, 0), false);
lgr_if_needed(multiplicand, x_xstart);
z_mlgr(product, yz_idx); // multiplicand * yz_idx -> product::multiplicand
clear_reg(yz_idx);
mem2reg_opt(yz_idx, Address(z, Z_R7, 0), false);
add2_with_carry(product, product_low, yz_idx, carry);
z_sllg(Z_R7, idx, LogBytesPerInt);
reg2mem_opt(product_low, Address(z, Z_R7, 0), false);
rshift(product_low, 32);
lshift(product, 32);
z_ogr(product_low, product);
lgr_if_needed(carry, product_low);
bind(L_post_third_loop_done);
}
void MacroAssembler::multiply_to_len(Register x, Register xlen,
Register y, Register ylen,
Register z,
Register tmp1, Register tmp2,
Register tmp3, Register tmp4,
Register tmp5) {
ShortBranchVerifier sbv(this);
assert_different_registers(x, xlen, y, ylen, z,
tmp1, tmp2, tmp3, tmp4, tmp5, Z_R1_scratch, Z_R7);
assert_different_registers(x, xlen, y, ylen, z,
tmp1, tmp2, tmp3, tmp4, tmp5, Z_R8);
z_stmg(Z_R7, Z_R13, _z_abi(gpr7), Z_SP);
// In openJdk, we store the argument as 32-bit value to slot.
Address zlen(Z_SP, _z_abi(remaining_cargs)); // Int in long on big endian.
const Register idx = tmp1;
const Register kdx = tmp2;
const Register xstart = tmp3;
const Register y_idx = tmp4;
const Register carry = tmp5;
const Register product = Z_R0_scratch;
const Register x_xstart = Z_R8;
// First Loop.
//
// final static long LONG_MASK = 0xffffffffL;
// int xstart = xlen - 1;
// int ystart = ylen - 1;
// long carry = 0;
// for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx-, kdx--) {
// long product = (y[idx] & LONG_MASK) * (x[xstart] & LONG_MASK) + carry;
// z[kdx] = (int)product;
// carry = product >>> 32;
// }
// z[xstart] = (int)carry;
//
lgr_if_needed(idx, ylen); // idx = ylen
z_llgf(kdx, zlen); // C2 does not respect int to long conversion for stub calls, thus load zero-extended.
clear_reg(carry); // carry = 0
Label L_done;
lgr_if_needed(xstart, xlen);
z_aghi(xstart, -1);
z_brl(L_done);
multiply_64_x_64_loop(x, xstart, x_xstart, y, y_idx, z, carry, product, idx, kdx);
NearLabel L_second_loop;
compare64_and_branch(kdx, RegisterOrConstant((intptr_t) 0), bcondEqual, L_second_loop);
NearLabel L_carry;
z_aghi(kdx, -1);
z_brz(L_carry);
// Store lower 32 bits of carry.
z_sllg(Z_R1_scratch, kdx, LogBytesPerInt);
reg2mem_opt(carry, Address(z, Z_R1_scratch, 0), false);
rshift(carry, 32);
z_aghi(kdx, -1);
bind(L_carry);
// Store upper 32 bits of carry.
z_sllg(Z_R1_scratch, kdx, LogBytesPerInt);
reg2mem_opt(carry, Address(z, Z_R1_scratch, 0), false);
// Second and third (nested) loops.
//
// for (int i = xstart-1; i >= 0; i--) { // Second loop
// carry = 0;
// for (int jdx=ystart, k=ystart+1+i; jdx >= 0; jdx--, k--) { // Third loop
// long product = (y[jdx] & LONG_MASK) * (x[i] & LONG_MASK) +
// (z[k] & LONG_MASK) + carry;
// z[k] = (int)product;
// carry = product >>> 32;
// }
// z[i] = (int)carry;
// }
//
// i = xlen, j = tmp1, k = tmp2, carry = tmp5, x[i] = rdx
const Register jdx = tmp1;
bind(L_second_loop);
clear_reg(carry); // carry = 0;
lgr_if_needed(jdx, ylen); // j = ystart+1
z_aghi(xstart, -1); // i = xstart-1;
z_brl(L_done);
// Use free slots in the current stackframe instead of push/pop.
Address zsave(Z_SP, _z_abi(carg_1));
reg2mem_opt(z, zsave);
Label L_last_x;
z_sllg(Z_R1_scratch, xstart, LogBytesPerInt);
load_address(z, Address(z, Z_R1_scratch, 4)); // z = z + k - j
z_aghi(xstart, -1); // i = xstart-1;
z_brl(L_last_x);
z_sllg(Z_R1_scratch, xstart, LogBytesPerInt);
mem2reg_opt(x_xstart, Address(x, Z_R1_scratch, 0));
Label L_third_loop_prologue;
bind(L_third_loop_prologue);
Address xsave(Z_SP, _z_abi(carg_2));
Address xlensave(Z_SP, _z_abi(carg_3));
Address ylensave(Z_SP, _z_abi(carg_4));
reg2mem_opt(x, xsave);
reg2mem_opt(xstart, xlensave);
reg2mem_opt(ylen, ylensave);
multiply_128_x_128_loop(x_xstart, y, z, y_idx, jdx, ylen, carry, product, x);
mem2reg_opt(z, zsave);
mem2reg_opt(x, xsave);
mem2reg_opt(xlen, xlensave); // This is the decrement of the loop counter!
mem2reg_opt(ylen, ylensave);
add2reg(tmp3, 1, xlen);
z_sllg(Z_R1_scratch, tmp3, LogBytesPerInt);
reg2mem_opt(carry, Address(z, Z_R1_scratch, 0), false);
z_aghi(tmp3, -1);
z_brl(L_done);
rshift(carry, 32);
z_sllg(Z_R1_scratch, tmp3, LogBytesPerInt);
reg2mem_opt(carry, Address(z, Z_R1_scratch, 0), false);
z_bru(L_second_loop);
// Next infrequent code is moved outside loops.
bind(L_last_x);
clear_reg(x_xstart);
mem2reg_opt(x_xstart, Address(x, (intptr_t) 0), false);
z_bru(L_third_loop_prologue);
bind(L_done);
z_lmg(Z_R7, Z_R13, _z_abi(gpr7), Z_SP);
}
#ifndef PRODUCT
// Assert if CC indicates "not equal" (check_equal==true) or "equal" (check_equal==false).
void MacroAssembler::asm_assert(bool check_equal, const char *msg, int id) {
Label ok;
if (check_equal) {
z_bre(ok);
} else {
z_brne(ok);
}
stop(msg, id);
bind(ok);
}
// Assert if CC indicates "low".
void MacroAssembler::asm_assert_low(const char *msg, int id) {
Label ok;
z_brnl(ok);
stop(msg, id);
bind(ok);
}
// Assert if CC indicates "high".
void MacroAssembler::asm_assert_high(const char *msg, int id) {
Label ok;
z_brnh(ok);
stop(msg, id);
bind(ok);
}
// Assert if CC indicates "not equal" (check_equal==true) or "equal" (check_equal==false)
// generate non-relocatable code.
void MacroAssembler::asm_assert_static(bool check_equal, const char *msg, int id) {
Label ok;
if (check_equal) { z_bre(ok); }
else { z_brne(ok); }
stop_static(msg, id);
bind(ok);
}
void MacroAssembler::asm_assert_mems_zero(bool check_equal, bool allow_relocation, int size, int64_t mem_offset,
Register mem_base, const char* msg, int id) {
switch (size) {
case 4:
load_and_test_int(Z_R0, Address(mem_base, mem_offset));
break;
case 8:
load_and_test_long(Z_R0, Address(mem_base, mem_offset));
break;
default:
ShouldNotReachHere();
}
if (allow_relocation) { asm_assert(check_equal, msg, id); }
else { asm_assert_static(check_equal, msg, id); }
}
// Check the condition
// expected_size == FP - SP
// after transformation:
// expected_size - FP + SP == 0
// Destroys Register expected_size if no tmp register is passed.
void MacroAssembler::asm_assert_frame_size(Register expected_size, Register tmp, const char* msg, int id) {
if (tmp == noreg) {
tmp = expected_size;
} else {
if (tmp != expected_size) {
z_lgr(tmp, expected_size);
}
z_algr(tmp, Z_SP);
z_slg(tmp, 0, Z_R0, Z_SP);
asm_assert_eq(msg, id);
}
}
#endif // !PRODUCT
void MacroAssembler::verify_thread() {
if (VerifyThread) {
unimplemented("", 117);
}
}
// Plausibility check for oops.
void MacroAssembler::verify_oop(Register oop, const char* msg) {
if (!VerifyOops) return;
BLOCK_COMMENT("verify_oop {");
Register tmp = Z_R0;
unsigned int nbytes_save = 5*BytesPerWord;
address entry = StubRoutines::verify_oop_subroutine_entry_address();
save_return_pc();
push_frame_abi160(nbytes_save);
z_stmg(Z_R1, Z_R5, frame::z_abi_160_size, Z_SP);
z_lgr(Z_ARG2, oop);
load_const(Z_ARG1, (address) msg);
load_const(Z_R1, entry);
z_lg(Z_R1, 0, Z_R1);
call_c(Z_R1);
z_lmg(Z_R1, Z_R5, frame::z_abi_160_size, Z_SP);
pop_frame();
restore_return_pc();
BLOCK_COMMENT("} verify_oop ");
}
const char* MacroAssembler::stop_types[] = {
"stop",
"untested",
"unimplemented",
"shouldnotreachhere"
};
static void stop_on_request(const char* tp, const char* msg) {
tty->print("Z assembly code requires stop: (%s) %s\n", tp, msg);
guarantee(false, "Z assembly code requires stop: %s", msg);
}
void MacroAssembler::stop(int type, const char* msg, int id) {
BLOCK_COMMENT(err_msg("stop: %s {", msg));
// Setup arguments.
load_const(Z_ARG1, (void*) stop_types[type%stop_end]);
load_const(Z_ARG2, (void*) msg);
get_PC(Z_R14); // Following code pushes a frame without entering a new function. Use current pc as return address.
save_return_pc(); // Saves return pc Z_R14.
push_frame_abi160(0);
call_VM_leaf(CAST_FROM_FN_PTR(address, stop_on_request), Z_ARG1, Z_ARG2);
// The plain disassembler does not recognize illtrap. It instead displays
// a 32-bit value. Issueing two illtraps assures the disassembler finds
// the proper beginning of the next instruction.
z_illtrap(); // Illegal instruction.
z_illtrap(); // Illegal instruction.
BLOCK_COMMENT(" } stop");
}
// Special version of stop() for code size reduction.
// Reuses the previously generated call sequence, if any.
// Generates the call sequence on its own, if necessary.
// Note: This code will work only in non-relocatable code!
// The relative address of the data elements (arg1, arg2) must not change.
// The reentry point must not move relative to it's users. This prerequisite
// should be given for "hand-written" code, if all chain calls are in the same code blob.
// Generated code must not undergo any transformation, e.g. ShortenBranches, to be safe.
address MacroAssembler::stop_chain(address reentry, int type, const char* msg, int id, bool allow_relocation) {
BLOCK_COMMENT(err_msg("stop_chain(%s,%s): %s {", reentry==NULL?"init":"cont", allow_relocation?"reloc ":"static", msg));
// Setup arguments.
if (allow_relocation) {
// Relocatable version (for comparison purposes). Remove after some time.
load_const(Z_ARG1, (void*) stop_types[type%stop_end]);
load_const(Z_ARG2, (void*) msg);
} else {
load_absolute_address(Z_ARG1, (address)stop_types[type%stop_end]);
load_absolute_address(Z_ARG2, (address)msg);
}
if ((reentry != NULL) && RelAddr::is_in_range_of_RelAddr16(reentry, pc())) {
BLOCK_COMMENT("branch to reentry point:");
z_brc(bcondAlways, reentry);
} else {
BLOCK_COMMENT("reentry point:");
reentry = pc(); // Re-entry point for subsequent stop calls.
save_return_pc(); // Saves return pc Z_R14.
push_frame_abi160(0);
if (allow_relocation) {
reentry = NULL; // Prevent reentry if code relocation is allowed.
call_VM_leaf(CAST_FROM_FN_PTR(address, stop_on_request), Z_ARG1, Z_ARG2);
} else {
call_VM_leaf_static(CAST_FROM_FN_PTR(address, stop_on_request), Z_ARG1, Z_ARG2);
}
z_illtrap(); // Illegal instruction as emergency stop, should the above call return.
}
BLOCK_COMMENT(" } stop_chain");
return reentry;
}
// Special version of stop() for code size reduction.
// Assumes constant relative addresses for data and runtime call.
void MacroAssembler::stop_static(int type, const char* msg, int id) {
stop_chain(NULL, type, msg, id, false);
}
void MacroAssembler::stop_subroutine() {
unimplemented("stop_subroutine", 710);
}
// Prints msg to stdout from within generated code..
void MacroAssembler::warn(const char* msg) {
RegisterSaver::save_live_registers(this, RegisterSaver::all_registers, Z_R14);
load_absolute_address(Z_R1, (address) warning);
load_absolute_address(Z_ARG1, (address) msg);
(void) call(Z_R1);
RegisterSaver::restore_live_registers(this, RegisterSaver::all_registers);
}
#ifndef PRODUCT
// Write pattern 0x0101010101010101 in region [low-before, high+after].
void MacroAssembler::zap_from_to(Register low, Register high, Register val, Register addr, int before, int after) {
if (!ZapEmptyStackFields) return;
BLOCK_COMMENT("zap memory region {");
load_const_optimized(val, 0x0101010101010101);
int size = before + after;
if (low == high && size < 5 && size > 0) {
int offset = -before*BytesPerWord;
for (int i = 0; i < size; ++i) {
z_stg(val, Address(low, offset));
offset +=(1*BytesPerWord);
}
} else {
add2reg(addr, -before*BytesPerWord, low);
if (after) {
#ifdef ASSERT
jlong check = after * BytesPerWord;
assert(Immediate::is_simm32(check) && Immediate::is_simm32(-check), "value not encodable !");
#endif
add2reg(high, after * BytesPerWord);
}
NearLabel loop;
bind(loop);
z_stg(val, Address(addr));
add2reg(addr, 8);
compare64_and_branch(addr, high, bcondNotHigh, loop);
if (after) {
add2reg(high, -after * BytesPerWord);
}
}
BLOCK_COMMENT("} zap memory region");
}
#endif // !PRODUCT
SkipIfEqual::SkipIfEqual(MacroAssembler* masm, const bool* flag_addr, bool value, Register _rscratch) {
_masm = masm;
_masm->load_absolute_address(_rscratch, (address)flag_addr);
_masm->load_and_test_int(_rscratch, Address(_rscratch));
if (value) {
_masm->z_brne(_label); // Skip if true, i.e. != 0.
} else {
_masm->z_bre(_label); // Skip if false, i.e. == 0.
}
}
SkipIfEqual::~SkipIfEqual() {
_masm->bind(_label);
}