8151340: aarch64: prefetch the destination word for write prior to ldxr/stxr loops.
Summary: aarch64: add prefetch for write prior to ldxr/stxr loops.
Reviewed-by: aph
Contributed-by: felix.yang@linaro.org
/*
* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2014, 2015, Red Hat Inc. 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 <sys/types.h>
#include "precompiled.hpp"
#include "asm/assembler.hpp"
#include "asm/assembler.inline.hpp"
#include "interpreter/interpreter.hpp"
#include "compiler/disassembler.hpp"
#include "memory/resourceArea.hpp"
#include "nativeInst_aarch64.hpp"
#include "oops/klass.inline.hpp"
#include "oops/oop.inline.hpp"
#include "opto/compile.hpp"
#include "opto/node.hpp"
#include "runtime/biasedLocking.hpp"
#include "runtime/icache.hpp"
#include "runtime/interfaceSupport.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/thread.hpp"
#if INCLUDE_ALL_GCS
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1SATBCardTableModRefBS.hpp"
#include "gc/g1/heapRegion.hpp"
#endif
#ifdef PRODUCT
#define BLOCK_COMMENT(str) /* nothing */
#define STOP(error) stop(error)
#else
#define BLOCK_COMMENT(str) block_comment(str)
#define STOP(error) block_comment(error); stop(error)
#endif
#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
// Patch any kind of instruction; there may be several instructions.
// Return the total length (in bytes) of the instructions.
int MacroAssembler::pd_patch_instruction_size(address branch, address target) {
int instructions = 1;
assert((uint64_t)target < (1ul << 48), "48-bit overflow in address constant");
long offset = (target - branch) >> 2;
unsigned insn = *(unsigned*)branch;
if ((Instruction_aarch64::extract(insn, 29, 24) & 0b111011) == 0b011000) {
// Load register (literal)
Instruction_aarch64::spatch(branch, 23, 5, offset);
} else if (Instruction_aarch64::extract(insn, 30, 26) == 0b00101) {
// Unconditional branch (immediate)
Instruction_aarch64::spatch(branch, 25, 0, offset);
} else if (Instruction_aarch64::extract(insn, 31, 25) == 0b0101010) {
// Conditional branch (immediate)
Instruction_aarch64::spatch(branch, 23, 5, offset);
} else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011010) {
// Compare & branch (immediate)
Instruction_aarch64::spatch(branch, 23, 5, offset);
} else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011011) {
// Test & branch (immediate)
Instruction_aarch64::spatch(branch, 18, 5, offset);
} else if (Instruction_aarch64::extract(insn, 28, 24) == 0b10000) {
// PC-rel. addressing
offset = target-branch;
int shift = Instruction_aarch64::extract(insn, 31, 31);
if (shift) {
u_int64_t dest = (u_int64_t)target;
uint64_t pc_page = (uint64_t)branch >> 12;
uint64_t adr_page = (uint64_t)target >> 12;
unsigned offset_lo = dest & 0xfff;
offset = adr_page - pc_page;
// We handle 4 types of PC relative addressing
// 1 - adrp Rx, target_page
// ldr/str Ry, [Rx, #offset_in_page]
// 2 - adrp Rx, target_page
// add Ry, Rx, #offset_in_page
// 3 - adrp Rx, target_page (page aligned reloc, offset == 0)
// movk Rx, #imm16<<32
// 4 - adrp Rx, target_page (page aligned reloc, offset == 0)
// In the first 3 cases we must check that Rx is the same in the adrp and the
// subsequent ldr/str, add or movk instruction. Otherwise we could accidentally end
// up treating a type 4 relocation as a type 1, 2 or 3 just because it happened
// to be followed by a random unrelated ldr/str, add or movk instruction.
//
unsigned insn2 = ((unsigned*)branch)[1];
if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 9, 5)) {
// Load/store register (unsigned immediate)
unsigned size = Instruction_aarch64::extract(insn2, 31, 30);
Instruction_aarch64::patch(branch + sizeof (unsigned),
21, 10, offset_lo >> size);
guarantee(((dest >> size) << size) == dest, "misaligned target");
instructions = 2;
} else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
// add (immediate)
Instruction_aarch64::patch(branch + sizeof (unsigned),
21, 10, offset_lo);
instructions = 2;
} else if (Instruction_aarch64::extract(insn2, 31, 21) == 0b11110010110 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
// movk #imm16<<32
Instruction_aarch64::patch(branch + 4, 20, 5, (uint64_t)target >> 32);
long dest = ((long)target & 0xffffffffL) | ((long)branch & 0xffff00000000L);
long pc_page = (long)branch >> 12;
long adr_page = (long)dest >> 12;
offset = adr_page - pc_page;
instructions = 2;
}
}
int offset_lo = offset & 3;
offset >>= 2;
Instruction_aarch64::spatch(branch, 23, 5, offset);
Instruction_aarch64::patch(branch, 30, 29, offset_lo);
} else if (Instruction_aarch64::extract(insn, 31, 21) == 0b11010010100) {
u_int64_t dest = (u_int64_t)target;
// Move wide constant
assert(nativeInstruction_at(branch+4)->is_movk(), "wrong insns in patch");
assert(nativeInstruction_at(branch+8)->is_movk(), "wrong insns in patch");
Instruction_aarch64::patch(branch, 20, 5, dest & 0xffff);
Instruction_aarch64::patch(branch+4, 20, 5, (dest >>= 16) & 0xffff);
Instruction_aarch64::patch(branch+8, 20, 5, (dest >>= 16) & 0xffff);
assert(target_addr_for_insn(branch) == target, "should be");
instructions = 3;
} else if (Instruction_aarch64::extract(insn, 31, 22) == 0b1011100101 &&
Instruction_aarch64::extract(insn, 4, 0) == 0b11111) {
// nothing to do
assert(target == 0, "did not expect to relocate target for polling page load");
} else {
ShouldNotReachHere();
}
return instructions * NativeInstruction::instruction_size;
}
int MacroAssembler::patch_oop(address insn_addr, address o) {
int instructions;
unsigned insn = *(unsigned*)insn_addr;
assert(nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
// OOPs are either narrow (32 bits) or wide (48 bits). We encode
// narrow OOPs by setting the upper 16 bits in the first
// instruction.
if (Instruction_aarch64::extract(insn, 31, 21) == 0b11010010101) {
// Move narrow OOP
narrowOop n = oopDesc::encode_heap_oop((oop)o);
Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
instructions = 2;
} else {
// Move wide OOP
assert(nativeInstruction_at(insn_addr+8)->is_movk(), "wrong insns in patch");
uintptr_t dest = (uintptr_t)o;
Instruction_aarch64::patch(insn_addr, 20, 5, dest & 0xffff);
Instruction_aarch64::patch(insn_addr+4, 20, 5, (dest >>= 16) & 0xffff);
Instruction_aarch64::patch(insn_addr+8, 20, 5, (dest >>= 16) & 0xffff);
instructions = 3;
}
return instructions * NativeInstruction::instruction_size;
}
address MacroAssembler::target_addr_for_insn(address insn_addr, unsigned insn) {
long offset = 0;
if ((Instruction_aarch64::extract(insn, 29, 24) & 0b011011) == 0b00011000) {
// Load register (literal)
offset = Instruction_aarch64::sextract(insn, 23, 5);
return address(((uint64_t)insn_addr + (offset << 2)));
} else if (Instruction_aarch64::extract(insn, 30, 26) == 0b00101) {
// Unconditional branch (immediate)
offset = Instruction_aarch64::sextract(insn, 25, 0);
} else if (Instruction_aarch64::extract(insn, 31, 25) == 0b0101010) {
// Conditional branch (immediate)
offset = Instruction_aarch64::sextract(insn, 23, 5);
} else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011010) {
// Compare & branch (immediate)
offset = Instruction_aarch64::sextract(insn, 23, 5);
} else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011011) {
// Test & branch (immediate)
offset = Instruction_aarch64::sextract(insn, 18, 5);
} else if (Instruction_aarch64::extract(insn, 28, 24) == 0b10000) {
// PC-rel. addressing
offset = Instruction_aarch64::extract(insn, 30, 29);
offset |= Instruction_aarch64::sextract(insn, 23, 5) << 2;
int shift = Instruction_aarch64::extract(insn, 31, 31) ? 12 : 0;
if (shift) {
offset <<= shift;
uint64_t target_page = ((uint64_t)insn_addr) + offset;
target_page &= ((uint64_t)-1) << shift;
// Return the target address for the following sequences
// 1 - adrp Rx, target_page
// ldr/str Ry, [Rx, #offset_in_page]
// 2 - adrp Rx, target_page
// add Ry, Rx, #offset_in_page
// 3 - adrp Rx, target_page (page aligned reloc, offset == 0)
// movk Rx, #imm12<<32
// 4 - adrp Rx, target_page (page aligned reloc, offset == 0)
//
// In the first two cases we check that the register is the same and
// return the target_page + the offset within the page.
// Otherwise we assume it is a page aligned relocation and return
// the target page only.
//
unsigned insn2 = ((unsigned*)insn_addr)[1];
if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 9, 5)) {
// Load/store register (unsigned immediate)
unsigned int byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
unsigned int size = Instruction_aarch64::extract(insn2, 31, 30);
return address(target_page + (byte_offset << size));
} else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
// add (immediate)
unsigned int byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
return address(target_page + byte_offset);
} else {
if (Instruction_aarch64::extract(insn2, 31, 21) == 0b11110010110 &&
Instruction_aarch64::extract(insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
target_page = (target_page & 0xffffffff) |
((uint64_t)Instruction_aarch64::extract(insn2, 20, 5) << 32);
}
return (address)target_page;
}
} else {
ShouldNotReachHere();
}
} else if (Instruction_aarch64::extract(insn, 31, 23) == 0b110100101) {
u_int32_t *insns = (u_int32_t *)insn_addr;
// Move wide constant: movz, movk, movk. See movptr().
assert(nativeInstruction_at(insns+1)->is_movk(), "wrong insns in patch");
assert(nativeInstruction_at(insns+2)->is_movk(), "wrong insns in patch");
return address(u_int64_t(Instruction_aarch64::extract(insns[0], 20, 5))
+ (u_int64_t(Instruction_aarch64::extract(insns[1], 20, 5)) << 16)
+ (u_int64_t(Instruction_aarch64::extract(insns[2], 20, 5)) << 32));
} else if (Instruction_aarch64::extract(insn, 31, 22) == 0b1011100101 &&
Instruction_aarch64::extract(insn, 4, 0) == 0b11111) {
return 0;
} else {
ShouldNotReachHere();
}
return address(((uint64_t)insn_addr + (offset << 2)));
}
void MacroAssembler::serialize_memory(Register thread, Register tmp) {
dsb(Assembler::SY);
}
void MacroAssembler::reset_last_Java_frame(bool clear_fp,
bool clear_pc) {
// we must set sp to zero to clear frame
str(zr, Address(rthread, JavaThread::last_Java_sp_offset()));
// must clear fp, so that compiled frames are not confused; it is
// possible that we need it only for debugging
if (clear_fp) {
str(zr, Address(rthread, JavaThread::last_Java_fp_offset()));
}
if (clear_pc) {
str(zr, Address(rthread, JavaThread::last_Java_pc_offset()));
}
}
// Calls to C land
//
// When entering C land, the rfp, & resp of the last Java frame have to be recorded
// in the (thread-local) JavaThread object. When leaving C land, the last Java fp
// has to be reset to 0. This is required to allow proper stack traversal.
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
Register last_java_pc,
Register scratch) {
if (last_java_pc->is_valid()) {
str(last_java_pc, Address(rthread,
JavaThread::frame_anchor_offset()
+ JavaFrameAnchor::last_Java_pc_offset()));
}
// determine last_java_sp register
if (last_java_sp == sp) {
mov(scratch, sp);
last_java_sp = scratch;
} else if (!last_java_sp->is_valid()) {
last_java_sp = esp;
}
str(last_java_sp, Address(rthread, JavaThread::last_Java_sp_offset()));
// last_java_fp is optional
if (last_java_fp->is_valid()) {
str(last_java_fp, Address(rthread, JavaThread::last_Java_fp_offset()));
}
}
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
address last_java_pc,
Register scratch) {
if (last_java_pc != NULL) {
adr(scratch, last_java_pc);
} else {
// FIXME: This is almost never correct. We should delete all
// cases of set_last_Java_frame with last_java_pc=NULL and use the
// correct return address instead.
adr(scratch, pc());
}
str(scratch, Address(rthread,
JavaThread::frame_anchor_offset()
+ JavaFrameAnchor::last_Java_pc_offset()));
set_last_Java_frame(last_java_sp, last_java_fp, noreg, scratch);
}
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
Label &L,
Register scratch) {
if (L.is_bound()) {
set_last_Java_frame(last_java_sp, last_java_fp, target(L), scratch);
} else {
InstructionMark im(this);
L.add_patch_at(code(), locator());
set_last_Java_frame(last_java_sp, last_java_fp, (address)NULL, scratch);
}
}
void MacroAssembler::far_call(Address entry, CodeBuffer *cbuf, Register tmp) {
assert(ReservedCodeCacheSize < 4*G, "branch out of range");
assert(CodeCache::find_blob(entry.target()) != NULL,
"destination of far call not found in code cache");
if (far_branches()) {
unsigned long offset;
// We can use ADRP here because we know that the total size of
// the code cache cannot exceed 2Gb.
adrp(tmp, entry, offset);
add(tmp, tmp, offset);
if (cbuf) cbuf->set_insts_mark();
blr(tmp);
} else {
if (cbuf) cbuf->set_insts_mark();
bl(entry);
}
}
void MacroAssembler::far_jump(Address entry, CodeBuffer *cbuf, Register tmp) {
assert(ReservedCodeCacheSize < 4*G, "branch out of range");
assert(CodeCache::find_blob(entry.target()) != NULL,
"destination of far call not found in code cache");
if (far_branches()) {
unsigned long offset;
// We can use ADRP here because we know that the total size of
// the code cache cannot exceed 2Gb.
adrp(tmp, entry, offset);
add(tmp, tmp, offset);
if (cbuf) cbuf->set_insts_mark();
br(tmp);
} else {
if (cbuf) cbuf->set_insts_mark();
b(entry);
}
}
int MacroAssembler::biased_locking_enter(Register lock_reg,
Register obj_reg,
Register swap_reg,
Register tmp_reg,
bool swap_reg_contains_mark,
Label& done,
Label* slow_case,
BiasedLockingCounters* counters) {
assert(UseBiasedLocking, "why call this otherwise?");
assert_different_registers(lock_reg, obj_reg, swap_reg);
if (PrintBiasedLockingStatistics && counters == NULL)
counters = BiasedLocking::counters();
assert_different_registers(lock_reg, obj_reg, swap_reg, tmp_reg, rscratch1, rscratch2, noreg);
assert(markOopDesc::age_shift == markOopDesc::lock_bits + markOopDesc::biased_lock_bits, "biased locking makes assumptions about bit layout");
Address mark_addr (obj_reg, oopDesc::mark_offset_in_bytes());
Address klass_addr (obj_reg, oopDesc::klass_offset_in_bytes());
Address saved_mark_addr(lock_reg, 0);
// 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
// First check to see whether biasing is even enabled for this object
Label cas_label;
int null_check_offset = -1;
if (!swap_reg_contains_mark) {
null_check_offset = offset();
ldr(swap_reg, mark_addr);
}
andr(tmp_reg, swap_reg, markOopDesc::biased_lock_mask_in_place);
cmp(tmp_reg, markOopDesc::biased_lock_pattern);
br(Assembler::NE, cas_label);
// The bias pattern is present in the object's header. Need to check
// whether the bias owner and the epoch are both still current.
load_prototype_header(tmp_reg, obj_reg);
orr(tmp_reg, tmp_reg, rthread);
eor(tmp_reg, swap_reg, tmp_reg);
andr(tmp_reg, tmp_reg, ~((int) markOopDesc::age_mask_in_place));
if (counters != NULL) {
Label around;
cbnz(tmp_reg, around);
atomic_incw(Address((address)counters->biased_lock_entry_count_addr()), tmp_reg, rscratch1, rscratch2);
b(done);
bind(around);
} else {
cbz(tmp_reg, done);
}
Label try_revoke_bias;
Label try_rebias;
// 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.
andr(rscratch1, tmp_reg, markOopDesc::biased_lock_mask_in_place);
cbnz(rscratch1, 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.
andr(rscratch1, tmp_reg, markOopDesc::epoch_mask_in_place);
cbnz(rscratch1, 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.
{
Label here;
mov(rscratch1, markOopDesc::biased_lock_mask_in_place | markOopDesc::age_mask_in_place | markOopDesc::epoch_mask_in_place);
andr(swap_reg, swap_reg, rscratch1);
orr(tmp_reg, swap_reg, rthread);
cmpxchgptr(swap_reg, tmp_reg, obj_reg, rscratch1, here, slow_case);
// 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.
bind(here);
if (counters != NULL) {
atomic_incw(Address((address)counters->anonymously_biased_lock_entry_count_addr()),
tmp_reg, rscratch1, rscratch2);
}
}
b(done);
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.
//
// FIXME: due to a lack of registers we currently blow away the age
// bits in this situation. Should attempt to preserve them.
{
Label here;
load_prototype_header(tmp_reg, obj_reg);
orr(tmp_reg, rthread, tmp_reg);
cmpxchgptr(swap_reg, tmp_reg, obj_reg, rscratch1, here, slow_case);
// If the biasing toward our thread failed, then another thread
// succeeded in biasing it toward itself and we need to revoke that
// bias. The revocation will occur in the runtime in the slow case.
bind(here);
if (counters != NULL) {
atomic_incw(Address((address)counters->rebiased_lock_entry_count_addr()),
tmp_reg, rscratch1, rscratch2);
}
}
b(done);
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.
//
// FIXME: due to a lack of registers we currently blow away the age
// bits in this situation. Should attempt to preserve them.
{
Label here, nope;
load_prototype_header(tmp_reg, obj_reg);
cmpxchgptr(swap_reg, tmp_reg, obj_reg, rscratch1, here, &nope);
bind(here);
// 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 (counters != NULL) {
atomic_incw(Address((address)counters->revoked_lock_entry_count_addr()), tmp_reg,
rscratch1, rscratch2);
}
bind(nope);
}
bind(cas_label);
return null_check_offset;
}
void MacroAssembler::biased_locking_exit(Register obj_reg, Register temp_reg, Label& done) {
assert(UseBiasedLocking, "why call this otherwise?");
// 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.
ldr(temp_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
andr(temp_reg, temp_reg, markOopDesc::biased_lock_mask_in_place);
cmp(temp_reg, markOopDesc::biased_lock_pattern);
br(Assembler::EQ, done);
}
// added to make this compile
REGISTER_DEFINITION(Register, noreg);
static void pass_arg0(MacroAssembler* masm, Register arg) {
if (c_rarg0 != arg ) {
masm->mov(c_rarg0, arg);
}
}
static void pass_arg1(MacroAssembler* masm, Register arg) {
if (c_rarg1 != arg ) {
masm->mov(c_rarg1, arg);
}
}
static void pass_arg2(MacroAssembler* masm, Register arg) {
if (c_rarg2 != arg ) {
masm->mov(c_rarg2, arg);
}
}
static void pass_arg3(MacroAssembler* masm, Register arg) {
if (c_rarg3 != arg ) {
masm->mov(c_rarg3, arg);
}
}
void MacroAssembler::call_VM_base(Register oop_result,
Register java_thread,
Register last_java_sp,
address entry_point,
int number_of_arguments,
bool check_exceptions) {
// determine java_thread register
if (!java_thread->is_valid()) {
java_thread = rthread;
}
// determine last_java_sp register
if (!last_java_sp->is_valid()) {
last_java_sp = esp;
}
// debugging support
assert(number_of_arguments >= 0 , "cannot have negative number of arguments");
assert(java_thread == rthread, "unexpected register");
#ifdef ASSERT
// TraceBytecodes does not use r12 but saves it over the call, so don't verify
// if ((UseCompressedOops || UseCompressedClassPointers) && !TraceBytecodes) verify_heapbase("call_VM_base: heap base corrupted?");
#endif // ASSERT
assert(java_thread != oop_result , "cannot use the same register for java_thread & oop_result");
assert(java_thread != last_java_sp, "cannot use the same register for java_thread & last_java_sp");
// push java thread (becomes first argument of C function)
mov(c_rarg0, java_thread);
// set last Java frame before call
assert(last_java_sp != rfp, "can't use rfp");
Label l;
set_last_Java_frame(last_java_sp, rfp, l, rscratch1);
// do the call, remove parameters
MacroAssembler::call_VM_leaf_base(entry_point, number_of_arguments, &l);
// reset last Java frame
// Only interpreter should have to clear fp
reset_last_Java_frame(true, true);
// C++ interp handles this in the interpreter
check_and_handle_popframe(java_thread);
check_and_handle_earlyret(java_thread);
if (check_exceptions) {
// check for pending exceptions (java_thread is set upon return)
ldr(rscratch1, Address(java_thread, in_bytes(Thread::pending_exception_offset())));
Label ok;
cbz(rscratch1, ok);
lea(rscratch1, RuntimeAddress(StubRoutines::forward_exception_entry()));
br(rscratch1);
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, java_thread);
}
}
void MacroAssembler::call_VM_helper(Register oop_result, address entry_point, int number_of_arguments, bool check_exceptions) {
call_VM_base(oop_result, noreg, noreg, entry_point, number_of_arguments, check_exceptions);
}
// Maybe emit a call via a trampoline. If the code cache is small
// trampolines won't be emitted.
address MacroAssembler::trampoline_call(Address entry, CodeBuffer *cbuf) {
assert(entry.rspec().type() == relocInfo::runtime_call_type
|| entry.rspec().type() == relocInfo::opt_virtual_call_type
|| entry.rspec().type() == relocInfo::static_call_type
|| entry.rspec().type() == relocInfo::virtual_call_type, "wrong reloc type");
unsigned int start_offset = offset();
if (far_branches() && !Compile::current()->in_scratch_emit_size()) {
address stub = emit_trampoline_stub(start_offset, entry.target());
if (stub == NULL) {
return NULL; // CodeCache is full
}
}
if (cbuf) cbuf->set_insts_mark();
relocate(entry.rspec());
if (!far_branches()) {
bl(entry.target());
} else {
bl(pc());
}
// just need to return a non-null address
return pc();
}
// Emit a trampoline stub for a call to a target which is too far away.
//
// code sequences:
//
// call-site:
// branch-and-link to <destination> or <trampoline stub>
//
// Related trampoline stub for this call site in the stub section:
// load the call target from the constant pool
// branch (LR still points to the call site above)
address MacroAssembler::emit_trampoline_stub(int insts_call_instruction_offset,
address dest) {
address stub = start_a_stub(Compile::MAX_stubs_size/2);
if (stub == NULL) {
return NULL; // CodeBuffer::expand failed
}
// Create a trampoline stub relocation which relates this trampoline stub
// with the call instruction at insts_call_instruction_offset in the
// instructions code-section.
align(wordSize);
relocate(trampoline_stub_Relocation::spec(code()->insts()->start()
+ insts_call_instruction_offset));
const int stub_start_offset = offset();
// Now, create the trampoline stub's code:
// - load the call
// - call
Label target;
ldr(rscratch1, target);
br(rscratch1);
bind(target);
assert(offset() - stub_start_offset == NativeCallTrampolineStub::data_offset,
"should be");
emit_int64((int64_t)dest);
const address stub_start_addr = addr_at(stub_start_offset);
assert(is_NativeCallTrampolineStub_at(stub_start_addr), "doesn't look like a trampoline");
end_a_stub();
return stub;
}
address MacroAssembler::ic_call(address entry, jint method_index) {
RelocationHolder rh = virtual_call_Relocation::spec(pc(), method_index);
// address const_ptr = long_constant((jlong)Universe::non_oop_word());
// unsigned long offset;
// ldr_constant(rscratch2, const_ptr);
movptr(rscratch2, (uintptr_t)Universe::non_oop_word());
return trampoline_call(Address(entry, rh));
}
// Implementation of call_VM versions
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
bool check_exceptions) {
call_VM_helper(oop_result, entry_point, 0, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
bool check_exceptions) {
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 1, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
Register arg_2,
bool check_exceptions) {
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 2, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
Register arg_2,
Register arg_3,
bool check_exceptions) {
assert(arg_1 != c_rarg3, "smashed arg");
assert(arg_2 != c_rarg3, "smashed arg");
pass_arg3(this, arg_3);
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 3, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
int number_of_arguments,
bool check_exceptions) {
call_VM_base(oop_result, rthread, last_java_sp, entry_point, number_of_arguments, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
Register arg_1,
bool check_exceptions) {
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 1, 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) {
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 2, 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) {
assert(arg_1 != c_rarg3, "smashed arg");
assert(arg_2 != c_rarg3, "smashed arg");
pass_arg3(this, arg_3);
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 3, check_exceptions);
}
void MacroAssembler::get_vm_result(Register oop_result, Register java_thread) {
ldr(oop_result, Address(java_thread, JavaThread::vm_result_offset()));
str(zr, Address(java_thread, JavaThread::vm_result_offset()));
verify_oop(oop_result, "broken oop in call_VM_base");
}
void MacroAssembler::get_vm_result_2(Register metadata_result, Register java_thread) {
ldr(metadata_result, Address(java_thread, JavaThread::vm_result_2_offset()));
str(zr, Address(java_thread, JavaThread::vm_result_2_offset()));
}
void MacroAssembler::align(int modulus) {
while (offset() % modulus != 0) nop();
}
// these are no-ops overridden by InterpreterMacroAssembler
void MacroAssembler::check_and_handle_earlyret(Register java_thread) { }
void MacroAssembler::check_and_handle_popframe(Register java_thread) { }
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);
// load indirectly to solve generation ordering problem
ldr(tmp, ExternalAddress((address) delayed_value_addr));
if (offset != 0)
add(tmp, tmp, offset);
return RegisterOrConstant(tmp);
}
void MacroAssembler:: notify(int type) {
if (type == bytecode_start) {
// set_last_Java_frame(esp, rfp, (address)NULL);
Assembler:: notify(type);
// reset_last_Java_frame(true, false);
}
else
Assembler:: notify(type);
}
// Look up the method for a megamorphic invokeinterface call.
// The target method is determined by <intf_klass, itable_index>.
// The receiver klass is in recv_klass.
// On success, the result will be in method_result, and execution falls through.
// On failure, execution transfers to the given label.
void MacroAssembler::lookup_interface_method(Register recv_klass,
Register intf_klass,
RegisterOrConstant itable_index,
Register method_result,
Register scan_temp,
Label& L_no_such_interface) {
assert_different_registers(recv_klass, intf_klass, method_result, scan_temp);
assert(itable_index.is_constant() || itable_index.as_register() == method_result,
"caller must use same register for non-constant itable index as for method");
// Compute start of first itableOffsetEntry (which is at the end of the vtable)
int vtable_base = in_bytes(Klass::vtable_start_offset());
int itentry_off = itableMethodEntry::method_offset_in_bytes();
int scan_step = itableOffsetEntry::size() * wordSize;
int vte_size = vtableEntry::size_in_bytes();
assert(vte_size == wordSize, "else adjust times_vte_scale");
ldrw(scan_temp, Address(recv_klass, Klass::vtable_length_offset()));
// %%% Could store the aligned, prescaled offset in the klassoop.
// lea(scan_temp, Address(recv_klass, scan_temp, times_vte_scale, vtable_base));
lea(scan_temp, Address(recv_klass, scan_temp, Address::lsl(3)));
add(scan_temp, scan_temp, vtable_base);
// Adjust recv_klass by scaled itable_index, so we can free itable_index.
assert(itableMethodEntry::size() * wordSize == wordSize, "adjust the scaling in the code below");
// lea(recv_klass, Address(recv_klass, itable_index, Address::times_ptr, itentry_off));
lea(recv_klass, Address(recv_klass, itable_index, Address::lsl(3)));
if (itentry_off)
add(recv_klass, recv_klass, itentry_off);
// for (scan = klass->itable(); scan->interface() != NULL; scan += scan_step) {
// if (scan->interface() == intf) {
// result = (klass + scan->offset() + itable_index);
// }
// }
Label search, found_method;
for (int peel = 1; peel >= 0; peel--) {
ldr(method_result, Address(scan_temp, itableOffsetEntry::interface_offset_in_bytes()));
cmp(intf_klass, method_result);
if (peel) {
br(Assembler::EQ, found_method);
} else {
br(Assembler::NE, search);
// (invert the test to fall through to found_method...)
}
if (!peel) break;
bind(search);
// Check that the previous entry is non-null. A null entry means that
// the receiver class doesn't implement the interface, and wasn't the
// same as when the caller was compiled.
cbz(method_result, L_no_such_interface);
add(scan_temp, scan_temp, scan_step);
}
bind(found_method);
// Got a hit.
ldr(scan_temp, Address(scan_temp, itableOffsetEntry::offset_offset_in_bytes()));
ldr(method_result, Address(recv_klass, scan_temp));
}
// virtual method calling
void MacroAssembler::lookup_virtual_method(Register recv_klass,
RegisterOrConstant vtable_index,
Register method_result) {
const int base = in_bytes(Klass::vtable_start_offset());
assert(vtableEntry::size() * wordSize == 8,
"adjust the scaling in the code below");
int vtable_offset_in_bytes = base + vtableEntry::method_offset_in_bytes();
if (vtable_index.is_register()) {
lea(method_result, Address(recv_klass,
vtable_index.as_register(),
Address::lsl(LogBytesPerWord)));
ldr(method_result, Address(method_result, vtable_offset_in_bytes));
} else {
vtable_offset_in_bytes += vtable_index.as_constant() * wordSize;
ldr(method_result, Address(recv_klass, vtable_offset_in_bytes));
}
}
void MacroAssembler::check_klass_subtype(Register sub_klass,
Register super_klass,
Register temp_reg,
Label& L_success) {
Label L_failure;
check_klass_subtype_fast_path(sub_klass, super_klass, temp_reg, &L_success, &L_failure, NULL);
check_klass_subtype_slow_path(sub_klass, super_klass, temp_reg, noreg, &L_success, NULL);
bind(L_failure);
}
void MacroAssembler::check_klass_subtype_fast_path(Register sub_klass,
Register super_klass,
Register temp_reg,
Label* L_success,
Label* L_failure,
Label* L_slow_path,
RegisterOrConstant super_check_offset) {
assert_different_registers(sub_klass, super_klass, temp_reg);
bool must_load_sco = (super_check_offset.constant_or_zero() == -1);
if (super_check_offset.is_register()) {
assert_different_registers(sub_klass, super_klass,
super_check_offset.as_register());
} else if (must_load_sco) {
assert(temp_reg != noreg, "supply either a temp or a register offset");
}
Label 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, "at most one NULL in the batch");
int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
int sco_offset = in_bytes(Klass::super_check_offset_offset());
Address super_check_offset_addr(super_klass, sco_offset);
// Hacked jmp, which may only be used just before L_fallthrough.
#define final_jmp(label) \
if (&(label) == &L_fallthrough) { /*do nothing*/ } \
else b(label) /*omit semi*/
// 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.
cmp(sub_klass, super_klass);
br(Assembler::EQ, *L_success);
// Check the supertype display:
if (must_load_sco) {
ldrw(temp_reg, super_check_offset_addr);
super_check_offset = RegisterOrConstant(temp_reg);
}
Address super_check_addr(sub_klass, super_check_offset);
ldr(rscratch1, super_check_addr);
cmp(super_klass, rscratch1); // load 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).
if (super_check_offset.is_register()) {
br(Assembler::EQ, *L_success);
cmp(super_check_offset.as_register(), sc_offset);
if (L_failure == &L_fallthrough) {
br(Assembler::EQ, *L_slow_path);
} else {
br(Assembler::NE, *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) {
br(Assembler::EQ, *L_success);
} else {
br(Assembler::NE, *L_slow_path);
final_jmp(*L_success);
}
} else {
// No slow path; it's a fast decision.
if (L_failure == &L_fallthrough) {
br(Assembler::EQ, *L_success);
} else {
br(Assembler::NE, *L_failure);
final_jmp(*L_success);
}
}
bind(L_fallthrough);
#undef final_jmp
}
// These two are taken from x86, but they look generally useful
// scans count pointer sized words at [addr] for occurence of value,
// generic
void MacroAssembler::repne_scan(Register addr, Register value, Register count,
Register scratch) {
Label Lloop, Lexit;
cbz(count, Lexit);
bind(Lloop);
ldr(scratch, post(addr, wordSize));
cmp(value, scratch);
br(EQ, Lexit);
sub(count, count, 1);
cbnz(count, Lloop);
bind(Lexit);
}
// scans count 4 byte words at [addr] for occurence of value,
// generic
void MacroAssembler::repne_scanw(Register addr, Register value, Register count,
Register scratch) {
Label Lloop, Lexit;
cbz(count, Lexit);
bind(Lloop);
ldrw(scratch, post(addr, wordSize));
cmpw(value, scratch);
br(EQ, Lexit);
sub(count, count, 1);
cbnz(count, Lloop);
bind(Lexit);
}
void MacroAssembler::check_klass_subtype_slow_path(Register sub_klass,
Register super_klass,
Register temp_reg,
Register temp2_reg,
Label* L_success,
Label* L_failure,
bool set_cond_codes) {
assert_different_registers(sub_klass, super_klass, temp_reg);
if (temp2_reg != noreg)
assert_different_registers(sub_klass, super_klass, temp_reg, temp2_reg, rscratch1);
#define IS_A_TEMP(reg) ((reg) == temp_reg || (reg) == temp2_reg)
Label 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");
// a couple of useful fields in sub_klass:
int ss_offset = in_bytes(Klass::secondary_supers_offset());
int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
Address secondary_supers_addr(sub_klass, ss_offset);
Address super_cache_addr( sub_klass, sc_offset);
BLOCK_COMMENT("check_klass_subtype_slow_path");
// Do a linear scan of the secondary super-klass chain.
// This code is rarely used, so simplicity is a virtue here.
// The repne_scan instruction uses fixed registers, which we must spill.
// Don't worry too much about pre-existing connections with the input regs.
assert(sub_klass != r0, "killed reg"); // killed by mov(r0, super)
assert(sub_klass != r2, "killed reg"); // killed by lea(r2, &pst_counter)
// Get super_klass value into r0 (even if it was in r5 or r2).
RegSet pushed_registers;
if (!IS_A_TEMP(r2)) pushed_registers += r2;
if (!IS_A_TEMP(r5)) pushed_registers += r5;
if (super_klass != r0 || UseCompressedOops) {
if (!IS_A_TEMP(r0)) pushed_registers += r0;
}
push(pushed_registers, sp);
#ifndef PRODUCT
mov(rscratch2, (address)&SharedRuntime::_partial_subtype_ctr);
Address pst_counter_addr(rscratch2);
ldr(rscratch1, pst_counter_addr);
add(rscratch1, rscratch1, 1);
str(rscratch1, pst_counter_addr);
#endif //PRODUCT
// We will consult the secondary-super array.
ldr(r5, secondary_supers_addr);
// Load the array length.
ldrw(r2, Address(r5, Array<Klass*>::length_offset_in_bytes()));
// Skip to start of data.
add(r5, r5, Array<Klass*>::base_offset_in_bytes());
cmp(sp, zr); // Clear Z flag; SP is never zero
// Scan R2 words at [R5] for an occurrence of R0.
// Set NZ/Z based on last compare.
repne_scan(r5, r0, r2, rscratch1);
// Unspill the temp. registers:
pop(pushed_registers, sp);
br(Assembler::NE, *L_failure);
// Success. Cache the super we found and proceed in triumph.
str(super_klass, super_cache_addr);
if (L_success != &L_fallthrough) {
b(*L_success);
}
#undef IS_A_TEMP
bind(L_fallthrough);
}
void MacroAssembler::verify_oop(Register reg, const char* s) {
if (!VerifyOops) return;
// Pass register number to verify_oop_subroutine
const char* b = NULL;
{
ResourceMark rm;
stringStream ss;
ss.print("verify_oop: %s: %s", reg->name(), s);
b = code_string(ss.as_string());
}
BLOCK_COMMENT("verify_oop {");
stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
mov(r0, reg);
mov(rscratch1, (address)b);
// call indirectly to solve generation ordering problem
lea(rscratch2, ExternalAddress(StubRoutines::verify_oop_subroutine_entry_address()));
ldr(rscratch2, Address(rscratch2));
blr(rscratch2);
ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
BLOCK_COMMENT("} verify_oop");
}
void MacroAssembler::verify_oop_addr(Address addr, const char* s) {
if (!VerifyOops) return;
const char* b = NULL;
{
ResourceMark rm;
stringStream ss;
ss.print("verify_oop_addr: %s", s);
b = code_string(ss.as_string());
}
BLOCK_COMMENT("verify_oop_addr {");
stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
// addr may contain sp so we will have to adjust it based on the
// pushes that we just did.
if (addr.uses(sp)) {
lea(r0, addr);
ldr(r0, Address(r0, 4 * wordSize));
} else {
ldr(r0, addr);
}
mov(rscratch1, (address)b);
// call indirectly to solve generation ordering problem
lea(rscratch2, ExternalAddress(StubRoutines::verify_oop_subroutine_entry_address()));
ldr(rscratch2, Address(rscratch2));
blr(rscratch2);
ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
BLOCK_COMMENT("} verify_oop_addr");
}
Address MacroAssembler::argument_address(RegisterOrConstant arg_slot,
int extra_slot_offset) {
// cf. TemplateTable::prepare_invoke(), if (load_receiver).
int stackElementSize = Interpreter::stackElementSize;
int offset = Interpreter::expr_offset_in_bytes(extra_slot_offset+0);
#ifdef ASSERT
int offset1 = Interpreter::expr_offset_in_bytes(extra_slot_offset+1);
assert(offset1 - offset == stackElementSize, "correct arithmetic");
#endif
if (arg_slot.is_constant()) {
return Address(esp, arg_slot.as_constant() * stackElementSize
+ offset);
} else {
add(rscratch1, esp, arg_slot.as_register(),
ext::uxtx, exact_log2(stackElementSize));
return Address(rscratch1, offset);
}
}
void MacroAssembler::call_VM_leaf_base(address entry_point,
int number_of_arguments,
Label *retaddr) {
call_VM_leaf_base1(entry_point, number_of_arguments, 0, ret_type_integral, retaddr);
}
void MacroAssembler::call_VM_leaf_base1(address entry_point,
int number_of_gp_arguments,
int number_of_fp_arguments,
ret_type type,
Label *retaddr) {
Label E, L;
stp(rscratch1, rmethod, Address(pre(sp, -2 * wordSize)));
// We add 1 to number_of_arguments because the thread in arg0 is
// not counted
mov(rscratch1, entry_point);
blrt(rscratch1, number_of_gp_arguments + 1, number_of_fp_arguments, type);
if (retaddr)
bind(*retaddr);
ldp(rscratch1, rmethod, Address(post(sp, 2 * wordSize)));
maybe_isb();
}
void MacroAssembler::call_VM_leaf(address entry_point, int number_of_arguments) {
call_VM_leaf_base(entry_point, number_of_arguments);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0) {
pass_arg0(this, arg_0);
call_VM_leaf_base(entry_point, 1);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
pass_arg0(this, arg_0);
pass_arg1(this, arg_1);
call_VM_leaf_base(entry_point, 2);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0,
Register arg_1, Register arg_2) {
pass_arg0(this, arg_0);
pass_arg1(this, arg_1);
pass_arg2(this, arg_2);
call_VM_leaf_base(entry_point, 3);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0) {
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 1);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
assert(arg_0 != c_rarg1, "smashed arg");
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 2);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2) {
assert(arg_0 != c_rarg2, "smashed arg");
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
assert(arg_0 != c_rarg1, "smashed arg");
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 3);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2, Register arg_3) {
assert(arg_0 != c_rarg3, "smashed arg");
assert(arg_1 != c_rarg3, "smashed arg");
assert(arg_2 != c_rarg3, "smashed arg");
pass_arg3(this, arg_3);
assert(arg_0 != c_rarg2, "smashed arg");
assert(arg_1 != c_rarg2, "smashed arg");
pass_arg2(this, arg_2);
assert(arg_0 != c_rarg1, "smashed arg");
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 4);
}
void MacroAssembler::null_check(Register reg, int offset) {
if (needs_explicit_null_check(offset)) {
// provoke OS NULL exception if reg = NULL by
// accessing M[reg] w/o changing any registers
// NOTE: this is plenty to provoke a segv
ldr(zr, Address(reg));
} else {
// nothing to do, (later) access of M[reg + offset]
// will provoke OS NULL exception if reg = NULL
}
}
// MacroAssembler protected routines needed to implement
// public methods
void MacroAssembler::mov(Register r, Address dest) {
code_section()->relocate(pc(), dest.rspec());
u_int64_t imm64 = (u_int64_t)dest.target();
movptr(r, imm64);
}
// Move a constant pointer into r. In AArch64 mode the virtual
// address space is 48 bits in size, so we only need three
// instructions to create a patchable instruction sequence that can
// reach anywhere.
void MacroAssembler::movptr(Register r, uintptr_t imm64) {
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%"PRIX64, imm64);
block_comment(buffer);
}
#endif
assert(imm64 < (1ul << 48), "48-bit overflow in address constant");
movz(r, imm64 & 0xffff);
imm64 >>= 16;
movk(r, imm64 & 0xffff, 16);
imm64 >>= 16;
movk(r, imm64 & 0xffff, 32);
}
// Macro to mov replicated immediate to vector register.
// Vd will get the following values for different arrangements in T
// imm32 == hex 000000gh T8B: Vd = ghghghghghghghgh
// imm32 == hex 000000gh T16B: Vd = ghghghghghghghghghghghghghghghgh
// imm32 == hex 0000efgh T4H: Vd = efghefghefghefgh
// imm32 == hex 0000efgh T8H: Vd = efghefghefghefghefghefghefghefgh
// imm32 == hex abcdefgh T2S: Vd = abcdefghabcdefgh
// imm32 == hex abcdefgh T4S: Vd = abcdefghabcdefghabcdefghabcdefgh
// T1D/T2D: invalid
void MacroAssembler::mov(FloatRegister Vd, SIMD_Arrangement T, u_int32_t imm32) {
assert(T != T1D && T != T2D, "invalid arrangement");
if (T == T8B || T == T16B) {
assert((imm32 & ~0xff) == 0, "extraneous bits in unsigned imm32 (T8B/T16B)");
movi(Vd, T, imm32 & 0xff, 0);
return;
}
u_int32_t nimm32 = ~imm32;
if (T == T4H || T == T8H) {
assert((imm32 & ~0xffff) == 0, "extraneous bits in unsigned imm32 (T4H/T8H)");
imm32 &= 0xffff;
nimm32 &= 0xffff;
}
u_int32_t x = imm32;
int movi_cnt = 0;
int movn_cnt = 0;
while (x) { if (x & 0xff) movi_cnt++; x >>= 8; }
x = nimm32;
while (x) { if (x & 0xff) movn_cnt++; x >>= 8; }
if (movn_cnt < movi_cnt) imm32 = nimm32;
unsigned lsl = 0;
while (imm32 && (imm32 & 0xff) == 0) { lsl += 8; imm32 >>= 8; }
if (movn_cnt < movi_cnt)
mvni(Vd, T, imm32 & 0xff, lsl);
else
movi(Vd, T, imm32 & 0xff, lsl);
imm32 >>= 8; lsl += 8;
while (imm32) {
while ((imm32 & 0xff) == 0) { lsl += 8; imm32 >>= 8; }
if (movn_cnt < movi_cnt)
bici(Vd, T, imm32 & 0xff, lsl);
else
orri(Vd, T, imm32 & 0xff, lsl);
lsl += 8; imm32 >>= 8;
}
}
void MacroAssembler::mov_immediate64(Register dst, u_int64_t imm64)
{
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%"PRIX64, imm64);
block_comment(buffer);
}
#endif
if (operand_valid_for_logical_immediate(false, imm64)) {
orr(dst, zr, imm64);
} else {
// we can use a combination of MOVZ or MOVN with
// MOVK to build up the constant
u_int64_t imm_h[4];
int zero_count = 0;
int neg_count = 0;
int i;
for (i = 0; i < 4; i++) {
imm_h[i] = ((imm64 >> (i * 16)) & 0xffffL);
if (imm_h[i] == 0) {
zero_count++;
} else if (imm_h[i] == 0xffffL) {
neg_count++;
}
}
if (zero_count == 4) {
// one MOVZ will do
movz(dst, 0);
} else if (neg_count == 4) {
// one MOVN will do
movn(dst, 0);
} else if (zero_count == 3) {
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0L) {
movz(dst, (u_int32_t)imm_h[i], (i << 4));
break;
}
}
} else if (neg_count == 3) {
// one MOVN will do
for (int i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
break;
}
}
} else if (zero_count == 2) {
// one MOVZ and one MOVK will do
for (i = 0; i < 3; i++) {
if (imm_h[i] != 0L) {
movz(dst, (u_int32_t)imm_h[i], (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0L) {
movk(dst, (u_int32_t)imm_h[i], (i << 4));
}
}
} else if (neg_count == 2) {
// one MOVN and one MOVK will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movk(dst, (u_int32_t)imm_h[i], (i << 4));
}
}
} else if (zero_count == 1) {
// one MOVZ and two MOVKs will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0L) {
movz(dst, (u_int32_t)imm_h[i], (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0x0L) {
movk(dst, (u_int32_t)imm_h[i], (i << 4));
}
}
} else if (neg_count == 1) {
// one MOVN and two MOVKs will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movk(dst, (u_int32_t)imm_h[i], (i << 4));
}
}
} else {
// use a MOVZ and 3 MOVKs (makes it easier to debug)
movz(dst, (u_int32_t)imm_h[0], 0);
for (i = 1; i < 4; i++) {
movk(dst, (u_int32_t)imm_h[i], (i << 4));
}
}
}
}
void MacroAssembler::mov_immediate32(Register dst, u_int32_t imm32)
{
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%"PRIX32, imm32);
block_comment(buffer);
}
#endif
if (operand_valid_for_logical_immediate(true, imm32)) {
orrw(dst, zr, imm32);
} else {
// we can use MOVZ, MOVN or two calls to MOVK to build up the
// constant
u_int32_t imm_h[2];
imm_h[0] = imm32 & 0xffff;
imm_h[1] = ((imm32 >> 16) & 0xffff);
if (imm_h[0] == 0) {
movzw(dst, imm_h[1], 16);
} else if (imm_h[0] == 0xffff) {
movnw(dst, imm_h[1] ^ 0xffff, 16);
} else if (imm_h[1] == 0) {
movzw(dst, imm_h[0], 0);
} else if (imm_h[1] == 0xffff) {
movnw(dst, imm_h[0] ^ 0xffff, 0);
} else {
// use a MOVZ and MOVK (makes it easier to debug)
movzw(dst, imm_h[0], 0);
movkw(dst, imm_h[1], 16);
}
}
}
// Form an address from base + offset in Rd. Rd may or may
// not actually be used: you must use the Address that is returned.
// It is up to you to ensure that the shift provided matches the size
// of your data.
Address MacroAssembler::form_address(Register Rd, Register base, long byte_offset, int shift) {
if (Address::offset_ok_for_immed(byte_offset, shift))
// It fits; no need for any heroics
return Address(base, byte_offset);
// Don't do anything clever with negative or misaligned offsets
unsigned mask = (1 << shift) - 1;
if (byte_offset < 0 || byte_offset & mask) {
mov(Rd, byte_offset);
add(Rd, base, Rd);
return Address(Rd);
}
// See if we can do this with two 12-bit offsets
{
unsigned long word_offset = byte_offset >> shift;
unsigned long masked_offset = word_offset & 0xfff000;
if (Address::offset_ok_for_immed(word_offset - masked_offset)
&& Assembler::operand_valid_for_add_sub_immediate(masked_offset << shift)) {
add(Rd, base, masked_offset << shift);
word_offset -= masked_offset;
return Address(Rd, word_offset << shift);
}
}
// Do it the hard way
mov(Rd, byte_offset);
add(Rd, base, Rd);
return Address(Rd);
}
void MacroAssembler::atomic_incw(Register counter_addr, Register tmp, Register tmp2) {
Label retry_load;
prfm(Address(counter_addr), PSTL1STRM);
bind(retry_load);
// flush and load exclusive from the memory location
ldxrw(tmp, counter_addr);
addw(tmp, tmp, 1);
// if we store+flush with no intervening write tmp wil be zero
stxrw(tmp2, tmp, counter_addr);
cbnzw(tmp2, retry_load);
}
int MacroAssembler::corrected_idivl(Register result, Register ra, Register rb,
bool want_remainder, Register scratch)
{
// Full implementation of Java idiv and irem. The function
// returns the (pc) offset of the div instruction - may be needed
// for implicit exceptions.
//
// constraint : ra/rb =/= scratch
// normal case
//
// input : ra: dividend
// rb: divisor
//
// result: either
// quotient (= ra idiv rb)
// remainder (= ra irem rb)
assert(ra != scratch && rb != scratch, "reg cannot be scratch");
int idivl_offset = offset();
if (! want_remainder) {
sdivw(result, ra, rb);
} else {
sdivw(scratch, ra, rb);
Assembler::msubw(result, scratch, rb, ra);
}
return idivl_offset;
}
int MacroAssembler::corrected_idivq(Register result, Register ra, Register rb,
bool want_remainder, Register scratch)
{
// Full implementation of Java ldiv and lrem. The function
// returns the (pc) offset of the div instruction - may be needed
// for implicit exceptions.
//
// constraint : ra/rb =/= scratch
// normal case
//
// input : ra: dividend
// rb: divisor
//
// result: either
// quotient (= ra idiv rb)
// remainder (= ra irem rb)
assert(ra != scratch && rb != scratch, "reg cannot be scratch");
int idivq_offset = offset();
if (! want_remainder) {
sdiv(result, ra, rb);
} else {
sdiv(scratch, ra, rb);
Assembler::msub(result, scratch, rb, ra);
}
return idivq_offset;
}
void MacroAssembler::membar(Membar_mask_bits order_constraint) {
address prev = pc() - NativeMembar::instruction_size;
if (prev == code()->last_membar()) {
NativeMembar *bar = NativeMembar_at(prev);
// We are merging two memory barrier instructions. On AArch64 we
// can do this simply by ORing them together.
bar->set_kind(bar->get_kind() | order_constraint);
BLOCK_COMMENT("merged membar");
} else {
code()->set_last_membar(pc());
dmb(Assembler::barrier(order_constraint));
}
}
// MacroAssembler routines found actually to be needed
void MacroAssembler::push(Register src)
{
str(src, Address(pre(esp, -1 * wordSize)));
}
void MacroAssembler::pop(Register dst)
{
ldr(dst, Address(post(esp, 1 * wordSize)));
}
// Note: load_unsigned_short used to be called load_unsigned_word.
int MacroAssembler::load_unsigned_short(Register dst, Address src) {
int off = offset();
ldrh(dst, src);
return off;
}
int MacroAssembler::load_unsigned_byte(Register dst, Address src) {
int off = offset();
ldrb(dst, src);
return off;
}
int MacroAssembler::load_signed_short(Register dst, Address src) {
int off = offset();
ldrsh(dst, src);
return off;
}
int MacroAssembler::load_signed_byte(Register dst, Address src) {
int off = offset();
ldrsb(dst, src);
return off;
}
int MacroAssembler::load_signed_short32(Register dst, Address src) {
int off = offset();
ldrshw(dst, src);
return off;
}
int MacroAssembler::load_signed_byte32(Register dst, Address src) {
int off = offset();
ldrsbw(dst, src);
return off;
}
void MacroAssembler::load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed, Register dst2) {
switch (size_in_bytes) {
case 8: ldr(dst, src); break;
case 4: ldrw(dst, src); break;
case 2: is_signed ? load_signed_short(dst, src) : load_unsigned_short(dst, src); break;
case 1: is_signed ? load_signed_byte( dst, src) : load_unsigned_byte( dst, src); break;
default: ShouldNotReachHere();
}
}
void MacroAssembler::store_sized_value(Address dst, Register src, size_t size_in_bytes, Register src2) {
switch (size_in_bytes) {
case 8: str(src, dst); break;
case 4: strw(src, dst); break;
case 2: strh(src, dst); break;
case 1: strb(src, dst); break;
default: ShouldNotReachHere();
}
}
void MacroAssembler::decrementw(Register reg, int value)
{
if (value < 0) { incrementw(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { subw(reg, reg, value); return; }
/* else */ {
guarantee(reg != rscratch2, "invalid dst for register decrement");
movw(rscratch2, (unsigned)value);
subw(reg, reg, rscratch2);
}
}
void MacroAssembler::decrement(Register reg, int value)
{
if (value < 0) { increment(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { sub(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register decrement");
mov(rscratch2, (unsigned long)value);
sub(reg, reg, rscratch2);
}
}
void MacroAssembler::decrementw(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address decrement");
ldrw(rscratch1, dst);
decrementw(rscratch1, value);
strw(rscratch1, dst);
}
void MacroAssembler::decrement(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid address for decrement");
ldr(rscratch1, dst);
decrement(rscratch1, value);
str(rscratch1, dst);
}
void MacroAssembler::incrementw(Register reg, int value)
{
if (value < 0) { decrementw(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { addw(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register increment");
movw(rscratch2, (unsigned)value);
addw(reg, reg, rscratch2);
}
}
void MacroAssembler::increment(Register reg, int value)
{
if (value < 0) { decrement(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { add(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register increment");
movw(rscratch2, (unsigned)value);
add(reg, reg, rscratch2);
}
}
void MacroAssembler::incrementw(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address increment");
ldrw(rscratch1, dst);
incrementw(rscratch1, value);
strw(rscratch1, dst);
}
void MacroAssembler::increment(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address increment");
ldr(rscratch1, dst);
increment(rscratch1, value);
str(rscratch1, dst);
}
void MacroAssembler::pusha() {
push(0x7fffffff, sp);
}
void MacroAssembler::popa() {
pop(0x7fffffff, sp);
}
// Push lots of registers in the bit set supplied. Don't push sp.
// Return the number of words pushed
int MacroAssembler::push(unsigned int bitset, Register stack) {
int words_pushed = 0;
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 30; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->encoding_nocheck();
count &= ~1; // Only push an even nuber of regs
if (count) {
stp(as_Register(regs[0]), as_Register(regs[1]),
Address(pre(stack, -count * wordSize)));
words_pushed += 2;
}
for (int i = 2; i < count; i += 2) {
stp(as_Register(regs[i]), as_Register(regs[i+1]),
Address(stack, i * wordSize));
words_pushed += 2;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
int MacroAssembler::pop(unsigned int bitset, Register stack) {
int words_pushed = 0;
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 30; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->encoding_nocheck();
count &= ~1;
for (int i = 2; i < count; i += 2) {
ldp(as_Register(regs[i]), as_Register(regs[i+1]),
Address(stack, i * wordSize));
words_pushed += 2;
}
if (count) {
ldp(as_Register(regs[0]), as_Register(regs[1]),
Address(post(stack, count * wordSize)));
words_pushed += 2;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
#ifdef ASSERT
void MacroAssembler::verify_heapbase(const char* msg) {
#if 0
assert (UseCompressedOops || UseCompressedClassPointers, "should be compressed");
assert (Universe::heap() != NULL, "java heap should be initialized");
if (CheckCompressedOops) {
Label ok;
push(1 << rscratch1->encoding(), sp); // cmpptr trashes rscratch1
cmpptr(rheapbase, ExternalAddress((address)Universe::narrow_ptrs_base_addr()));
br(Assembler::EQ, ok);
stop(msg);
bind(ok);
pop(1 << rscratch1->encoding(), sp);
}
#endif
}
#endif
void MacroAssembler::stop(const char* msg) {
address ip = pc();
pusha();
mov(c_rarg0, (address)msg);
mov(c_rarg1, (address)ip);
mov(c_rarg2, sp);
mov(c_rarg3, CAST_FROM_FN_PTR(address, MacroAssembler::debug64));
// call(c_rarg3);
blrt(c_rarg3, 3, 0, 1);
hlt(0);
}
// If a constant does not fit in an immediate field, generate some
// number of MOV instructions and then perform the operation.
void MacroAssembler::wrap_add_sub_imm_insn(Register Rd, Register Rn, unsigned imm,
add_sub_imm_insn insn1,
add_sub_reg_insn insn2) {
assert(Rd != zr, "Rd = zr and not setting flags?");
if (operand_valid_for_add_sub_immediate((int)imm)) {
(this->*insn1)(Rd, Rn, imm);
} else {
if (uabs(imm) < (1 << 24)) {
(this->*insn1)(Rd, Rn, imm & -(1 << 12));
(this->*insn1)(Rd, Rd, imm & ((1 << 12)-1));
} else {
assert_different_registers(Rd, Rn);
mov(Rd, (uint64_t)imm);
(this->*insn2)(Rd, Rn, Rd, LSL, 0);
}
}
}
// Seperate vsn which sets the flags. Optimisations are more restricted
// because we must set the flags correctly.
void MacroAssembler::wrap_adds_subs_imm_insn(Register Rd, Register Rn, unsigned imm,
add_sub_imm_insn insn1,
add_sub_reg_insn insn2) {
if (operand_valid_for_add_sub_immediate((int)imm)) {
(this->*insn1)(Rd, Rn, imm);
} else {
assert_different_registers(Rd, Rn);
assert(Rd != zr, "overflow in immediate operand");
mov(Rd, (uint64_t)imm);
(this->*insn2)(Rd, Rn, Rd, LSL, 0);
}
}
void MacroAssembler::add(Register Rd, Register Rn, RegisterOrConstant increment) {
if (increment.is_register()) {
add(Rd, Rn, increment.as_register());
} else {
add(Rd, Rn, increment.as_constant());
}
}
void MacroAssembler::addw(Register Rd, Register Rn, RegisterOrConstant increment) {
if (increment.is_register()) {
addw(Rd, Rn, increment.as_register());
} else {
addw(Rd, Rn, increment.as_constant());
}
}
void MacroAssembler::sub(Register Rd, Register Rn, RegisterOrConstant decrement) {
if (decrement.is_register()) {
sub(Rd, Rn, decrement.as_register());
} else {
sub(Rd, Rn, decrement.as_constant());
}
}
void MacroAssembler::subw(Register Rd, Register Rn, RegisterOrConstant decrement) {
if (decrement.is_register()) {
subw(Rd, Rn, decrement.as_register());
} else {
subw(Rd, Rn, decrement.as_constant());
}
}
void MacroAssembler::reinit_heapbase()
{
if (UseCompressedOops) {
if (Universe::is_fully_initialized()) {
mov(rheapbase, Universe::narrow_ptrs_base());
} else {
lea(rheapbase, ExternalAddress((address)Universe::narrow_ptrs_base_addr()));
ldr(rheapbase, Address(rheapbase));
}
}
}
// this simulates the behaviour of the x86 cmpxchg instruction using a
// load linked/store conditional pair. we use the acquire/release
// versions of these instructions so that we flush pending writes as
// per Java semantics.
// n.b the x86 version assumes the old value to be compared against is
// in rax and updates rax with the value located in memory if the
// cmpxchg fails. we supply a register for the old value explicitly
// the aarch64 load linked/store conditional instructions do not
// accept an offset. so, unlike x86, we must provide a plain register
// to identify the memory word to be compared/exchanged rather than a
// register+offset Address.
void MacroAssembler::cmpxchgptr(Register oldv, Register newv, Register addr, Register tmp,
Label &succeed, Label *fail) {
// oldv holds comparison value
// newv holds value to write in exchange
// addr identifies memory word to compare against/update
if (UseLSE) {
mov(tmp, oldv);
casal(Assembler::xword, oldv, newv, addr);
cmp(tmp, oldv);
br(Assembler::EQ, succeed);
membar(AnyAny);
} else {
Label retry_load, nope;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
// flush and load exclusive from the memory location
// and fail if it is not what we expect
ldaxr(tmp, addr);
cmp(tmp, oldv);
br(Assembler::NE, nope);
// if we store+flush with no intervening write tmp wil be zero
stlxr(tmp, newv, addr);
cbzw(tmp, succeed);
// retry so we only ever return after a load fails to compare
// ensures we don't return a stale value after a failed write.
b(retry_load);
// if the memory word differs we return it in oldv and signal a fail
bind(nope);
membar(AnyAny);
mov(oldv, tmp);
}
if (fail)
b(*fail);
}
void MacroAssembler::cmpxchgw(Register oldv, Register newv, Register addr, Register tmp,
Label &succeed, Label *fail) {
// oldv holds comparison value
// newv holds value to write in exchange
// addr identifies memory word to compare against/update
// tmp returns 0/1 for success/failure
if (UseLSE) {
mov(tmp, oldv);
casal(Assembler::word, oldv, newv, addr);
cmp(tmp, oldv);
br(Assembler::EQ, succeed);
membar(AnyAny);
} else {
Label retry_load, nope;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
// flush and load exclusive from the memory location
// and fail if it is not what we expect
ldaxrw(tmp, addr);
cmp(tmp, oldv);
br(Assembler::NE, nope);
// if we store+flush with no intervening write tmp wil be zero
stlxrw(tmp, newv, addr);
cbzw(tmp, succeed);
// retry so we only ever return after a load fails to compare
// ensures we don't return a stale value after a failed write.
b(retry_load);
// if the memory word differs we return it in oldv and signal a fail
bind(nope);
membar(AnyAny);
mov(oldv, tmp);
}
if (fail)
b(*fail);
}
// A generic CAS; success or failure is in the EQ flag.
void MacroAssembler::cmpxchg(Register addr, Register expected,
Register new_val,
enum operand_size size,
bool acquire, bool release,
Register tmp) {
if (UseLSE) {
mov(tmp, expected);
lse_cas(tmp, new_val, addr, size, acquire, release, /*not_pair*/ true);
cmp(tmp, expected);
} else {
BLOCK_COMMENT("cmpxchg {");
Label retry_load, done;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
load_exclusive(tmp, addr, size, acquire);
if (size == xword)
cmp(tmp, expected);
else
cmpw(tmp, expected);
br(Assembler::NE, done);
store_exclusive(tmp, new_val, addr, size, release);
cbnzw(tmp, retry_load);
bind(done);
BLOCK_COMMENT("} cmpxchg");
}
}
static bool different(Register a, RegisterOrConstant b, Register c) {
if (b.is_constant())
return a != c;
else
return a != b.as_register() && a != c && b.as_register() != c;
}
#define ATOMIC_OP(LDXR, OP, IOP, STXR) \
void MacroAssembler::atomic_##OP(Register prev, RegisterOrConstant incr, Register addr) { \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, incr, addr) ? prev : rscratch2; \
\
Label retry_load; \
prfm(Address(addr), PSTL1STRM); \
bind(retry_load); \
LDXR(result, addr); \
OP(rscratch1, result, incr); \
STXR(rscratch2, rscratch1, addr); \
cbnzw(rscratch2, retry_load); \
if (prev->is_valid() && prev != result) { \
IOP(prev, rscratch1, incr); \
} \
}
ATOMIC_OP(ldxr, add, sub, stxr)
ATOMIC_OP(ldxrw, addw, subw, stxrw)
#undef ATOMIC_OP
#define ATOMIC_XCHG(OP, LDXR, STXR) \
void MacroAssembler::atomic_##OP(Register prev, Register newv, Register addr) { \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, newv, addr) ? prev : rscratch2; \
\
Label retry_load; \
prfm(Address(addr), PSTL1STRM); \
bind(retry_load); \
LDXR(result, addr); \
STXR(rscratch1, newv, addr); \
cbnzw(rscratch1, retry_load); \
if (prev->is_valid() && prev != result) \
mov(prev, result); \
}
ATOMIC_XCHG(xchg, ldxr, stxr)
ATOMIC_XCHG(xchgw, ldxrw, stxrw)
#undef ATOMIC_XCHG
void MacroAssembler::incr_allocated_bytes(Register thread,
Register var_size_in_bytes,
int con_size_in_bytes,
Register t1) {
if (!thread->is_valid()) {
thread = rthread;
}
assert(t1->is_valid(), "need temp reg");
ldr(t1, Address(thread, in_bytes(JavaThread::allocated_bytes_offset())));
if (var_size_in_bytes->is_valid()) {
add(t1, t1, var_size_in_bytes);
} else {
add(t1, t1, con_size_in_bytes);
}
str(t1, Address(thread, in_bytes(JavaThread::allocated_bytes_offset())));
}
#ifndef PRODUCT
extern "C" void findpc(intptr_t x);
#endif
void MacroAssembler::debug64(char* msg, int64_t pc, int64_t regs[])
{
// In order to get locks to work, we need to fake a in_VM state
if (ShowMessageBoxOnError ) {
JavaThread* thread = JavaThread::current();
JavaThreadState saved_state = thread->thread_state();
thread->set_thread_state(_thread_in_vm);
#ifndef PRODUCT
if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
ttyLocker ttyl;
BytecodeCounter::print();
}
#endif
if (os::message_box(msg, "Execution stopped, print registers?")) {
ttyLocker ttyl;
tty->print_cr(" pc = 0x%016lx", pc);
#ifndef PRODUCT
tty->cr();
findpc(pc);
tty->cr();
#endif
tty->print_cr(" r0 = 0x%016lx", regs[0]);
tty->print_cr(" r1 = 0x%016lx", regs[1]);
tty->print_cr(" r2 = 0x%016lx", regs[2]);
tty->print_cr(" r3 = 0x%016lx", regs[3]);
tty->print_cr(" r4 = 0x%016lx", regs[4]);
tty->print_cr(" r5 = 0x%016lx", regs[5]);
tty->print_cr(" r6 = 0x%016lx", regs[6]);
tty->print_cr(" r7 = 0x%016lx", regs[7]);
tty->print_cr(" r8 = 0x%016lx", regs[8]);
tty->print_cr(" r9 = 0x%016lx", regs[9]);
tty->print_cr("r10 = 0x%016lx", regs[10]);
tty->print_cr("r11 = 0x%016lx", regs[11]);
tty->print_cr("r12 = 0x%016lx", regs[12]);
tty->print_cr("r13 = 0x%016lx", regs[13]);
tty->print_cr("r14 = 0x%016lx", regs[14]);
tty->print_cr("r15 = 0x%016lx", regs[15]);
tty->print_cr("r16 = 0x%016lx", regs[16]);
tty->print_cr("r17 = 0x%016lx", regs[17]);
tty->print_cr("r18 = 0x%016lx", regs[18]);
tty->print_cr("r19 = 0x%016lx", regs[19]);
tty->print_cr("r20 = 0x%016lx", regs[20]);
tty->print_cr("r21 = 0x%016lx", regs[21]);
tty->print_cr("r22 = 0x%016lx", regs[22]);
tty->print_cr("r23 = 0x%016lx", regs[23]);
tty->print_cr("r24 = 0x%016lx", regs[24]);
tty->print_cr("r25 = 0x%016lx", regs[25]);
tty->print_cr("r26 = 0x%016lx", regs[26]);
tty->print_cr("r27 = 0x%016lx", regs[27]);
tty->print_cr("r28 = 0x%016lx", regs[28]);
tty->print_cr("r30 = 0x%016lx", regs[30]);
tty->print_cr("r31 = 0x%016lx", regs[31]);
BREAKPOINT;
}
ThreadStateTransition::transition(thread, _thread_in_vm, saved_state);
} else {
ttyLocker ttyl;
::tty->print_cr("=============== DEBUG MESSAGE: %s ================\n",
msg);
assert(false, "DEBUG MESSAGE: %s", msg);
}
}
#ifdef BUILTIN_SIM
// routine to generate an x86 prolog for a stub function which
// bootstraps into the generated ARM code which directly follows the
// stub
//
// the argument encodes the number of general and fp registers
// passed by the caller and the callng convention (currently just
// the number of general registers and assumes C argument passing)
extern "C" {
int aarch64_stub_prolog_size();
void aarch64_stub_prolog();
void aarch64_prolog();
}
void MacroAssembler::c_stub_prolog(int gp_arg_count, int fp_arg_count, int ret_type,
address *prolog_ptr)
{
int calltype = (((ret_type & 0x3) << 8) |
((fp_arg_count & 0xf) << 4) |
(gp_arg_count & 0xf));
// the addresses for the x86 to ARM entry code we need to use
address start = pc();
// printf("start = %lx\n", start);
int byteCount = aarch64_stub_prolog_size();
// printf("byteCount = %x\n", byteCount);
int instructionCount = (byteCount + 3)/ 4;
// printf("instructionCount = %x\n", instructionCount);
for (int i = 0; i < instructionCount; i++) {
nop();
}
memcpy(start, (void*)aarch64_stub_prolog, byteCount);
// write the address of the setup routine and the call format at the
// end of into the copied code
u_int64_t *patch_end = (u_int64_t *)(start + byteCount);
if (prolog_ptr)
patch_end[-2] = (u_int64_t)prolog_ptr;
patch_end[-1] = calltype;
}
#endif
void MacroAssembler::push_call_clobbered_registers() {
push(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
// Push v0-v7, v16-v31.
for (int i = 30; i >= 0; i -= 2) {
if (i <= v7->encoding() || i >= v16->encoding()) {
stpd(as_FloatRegister(i), as_FloatRegister(i+1),
Address(pre(sp, -2 * wordSize)));
}
}
}
void MacroAssembler::pop_call_clobbered_registers() {
for (int i = 0; i < 32; i += 2) {
if (i <= v7->encoding() || i >= v16->encoding()) {
ldpd(as_FloatRegister(i), as_FloatRegister(i+1),
Address(post(sp, 2 * wordSize)));
}
}
pop(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
}
void MacroAssembler::push_CPU_state(bool save_vectors) {
push(0x3fffffff, sp); // integer registers except lr & sp
if (!save_vectors) {
for (int i = 30; i >= 0; i -= 2)
stpd(as_FloatRegister(i), as_FloatRegister(i+1),
Address(pre(sp, -2 * wordSize)));
} else {
for (int i = 30; i >= 0; i -= 2)
stpq(as_FloatRegister(i), as_FloatRegister(i+1),
Address(pre(sp, -4 * wordSize)));
}
}
void MacroAssembler::pop_CPU_state(bool restore_vectors) {
if (!restore_vectors) {
for (int i = 0; i < 32; i += 2)
ldpd(as_FloatRegister(i), as_FloatRegister(i+1),
Address(post(sp, 2 * wordSize)));
} else {
for (int i = 0; i < 32; i += 2)
ldpq(as_FloatRegister(i), as_FloatRegister(i+1),
Address(post(sp, 4 * wordSize)));
}
pop(0x3fffffff, sp); // integer registers except lr & sp
}
/**
* Helpers for multiply_to_len().
*/
void MacroAssembler::add2_with_carry(Register final_dest_hi, Register dest_hi, Register dest_lo,
Register src1, Register src2) {
adds(dest_lo, dest_lo, src1);
adc(dest_hi, dest_hi, zr);
adds(dest_lo, dest_lo, src2);
adc(final_dest_hi, dest_hi, zr);
}
// Generate an address from (r + r1 extend offset). "size" is the
// size of the operand. The result may be in rscratch2.
Address MacroAssembler::offsetted_address(Register r, Register r1,
Address::extend ext, int offset, int size) {
if (offset || (ext.shift() % size != 0)) {
lea(rscratch2, Address(r, r1, ext));
return Address(rscratch2, offset);
} else {
return Address(r, r1, ext);
}
}
Address MacroAssembler::spill_address(int size, int offset, Register tmp)
{
assert(offset >= 0, "spill to negative address?");
// Offset reachable ?
// Not aligned - 9 bits signed offset
// Aligned - 12 bits unsigned offset shifted
Register base = sp;
if ((offset & (size-1)) && offset >= (1<<8)) {
add(tmp, base, offset & ((1<<12)-1));
base = tmp;
offset &= -1<<12;
}
if (offset >= (1<<12) * size) {
add(tmp, base, offset & (((1<<12)-1)<<12));
base = tmp;
offset &= ~(((1<<12)-1)<<12);
}
return Address(base, offset);
}
/**
* 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;
subsw(xstart, xstart, 1);
br(Assembler::MI, L_one_x);
lea(rscratch1, Address(x, xstart, Address::lsl(LogBytesPerInt)));
ldr(x_xstart, Address(rscratch1));
ror(x_xstart, x_xstart, 32); // convert big-endian to little-endian
bind(L_first_loop);
subsw(idx, idx, 1);
br(Assembler::MI, L_first_loop_exit);
subsw(idx, idx, 1);
br(Assembler::MI, L_one_y);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldr(y_idx, Address(rscratch1));
ror(y_idx, y_idx, 32); // convert big-endian to little-endian
bind(L_multiply);
// AArch64 has a multiply-accumulate instruction that we can't use
// here because it has no way to process carries, so we have to use
// separate add and adc instructions. Bah.
umulh(rscratch1, x_xstart, y_idx); // x_xstart * y_idx -> rscratch1:product
mul(product, x_xstart, y_idx);
adds(product, product, carry);
adc(carry, rscratch1, zr); // x_xstart * y_idx + carry -> carry:product
subw(kdx, kdx, 2);
ror(product, product, 32); // back to big-endian
str(product, offsetted_address(z, kdx, Address::uxtw(LogBytesPerInt), 0, BytesPerLong));
b(L_first_loop);
bind(L_one_y);
ldrw(y_idx, Address(y, 0));
b(L_multiply);
bind(L_one_x);
ldrw(x_xstart, Address(x, 0));
b(L_first_loop);
bind(L_first_loop_exit);
}
/**
* Multiply 128 bit by 128. Unrolled inner loop.
*
*/
void MacroAssembler::multiply_128_x_128_loop(Register y, Register z,
Register carry, Register carry2,
Register idx, Register jdx,
Register yz_idx1, Register yz_idx2,
Register tmp, Register tmp3, Register tmp4,
Register tmp6, Register product_hi) {
// jlong carry, x[], y[], z[];
// int kdx = ystart+1;
// for (int idx=ystart-2; idx >= 0; idx -= 2) { // Third loop
// huge_128 tmp3 = (y[idx+1] * product_hi) + z[kdx+idx+1] + carry;
// jlong carry2 = (jlong)(tmp3 >>> 64);
// huge_128 tmp4 = (y[idx] * product_hi) + z[kdx+idx] + carry2;
// carry = (jlong)(tmp4 >>> 64);
// z[kdx+idx+1] = (jlong)tmp3;
// z[kdx+idx] = (jlong)tmp4;
// }
// idx += 2;
// if (idx > 0) {
// yz_idx1 = (y[idx] * product_hi) + z[kdx+idx] + carry;
// z[kdx+idx] = (jlong)yz_idx1;
// carry = (jlong)(yz_idx1 >>> 64);
// }
//
Label L_third_loop, L_third_loop_exit, L_post_third_loop_done;
lsrw(jdx, idx, 2);
bind(L_third_loop);
subsw(jdx, jdx, 1);
br(Assembler::MI, L_third_loop_exit);
subw(idx, idx, 4);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldp(yz_idx2, yz_idx1, Address(rscratch1, 0));
lea(tmp6, Address(z, idx, Address::uxtw(LogBytesPerInt)));
ror(yz_idx1, yz_idx1, 32); // convert big-endian to little-endian
ror(yz_idx2, yz_idx2, 32);
ldp(rscratch2, rscratch1, Address(tmp6, 0));
mul(tmp3, product_hi, yz_idx1); // yz_idx1 * product_hi -> tmp4:tmp3
umulh(tmp4, product_hi, yz_idx1);
ror(rscratch1, rscratch1, 32); // convert big-endian to little-endian
ror(rscratch2, rscratch2, 32);
mul(tmp, product_hi, yz_idx2); // yz_idx2 * product_hi -> carry2:tmp
umulh(carry2, product_hi, yz_idx2);
// propagate sum of both multiplications into carry:tmp4:tmp3
adds(tmp3, tmp3, carry);
adc(tmp4, tmp4, zr);
adds(tmp3, tmp3, rscratch1);
adcs(tmp4, tmp4, tmp);
adc(carry, carry2, zr);
adds(tmp4, tmp4, rscratch2);
adc(carry, carry, zr);
ror(tmp3, tmp3, 32); // convert little-endian to big-endian
ror(tmp4, tmp4, 32);
stp(tmp4, tmp3, Address(tmp6, 0));
b(L_third_loop);
bind (L_third_loop_exit);
andw (idx, idx, 0x3);
cbz(idx, L_post_third_loop_done);
Label L_check_1;
subsw(idx, idx, 2);
br(Assembler::MI, L_check_1);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldr(yz_idx1, Address(rscratch1, 0));
ror(yz_idx1, yz_idx1, 32);
mul(tmp3, product_hi, yz_idx1); // yz_idx1 * product_hi -> tmp4:tmp3
umulh(tmp4, product_hi, yz_idx1);
lea(rscratch1, Address(z, idx, Address::uxtw(LogBytesPerInt)));
ldr(yz_idx2, Address(rscratch1, 0));
ror(yz_idx2, yz_idx2, 32);
add2_with_carry(carry, tmp4, tmp3, carry, yz_idx2);
ror(tmp3, tmp3, 32);
str(tmp3, Address(rscratch1, 0));
bind (L_check_1);
andw (idx, idx, 0x1);
subsw(idx, idx, 1);
br(Assembler::MI, L_post_third_loop_done);
ldrw(tmp4, Address(y, idx, Address::uxtw(LogBytesPerInt)));
mul(tmp3, tmp4, product_hi); // tmp4 * product_hi -> carry2:tmp3
umulh(carry2, tmp4, product_hi);
ldrw(tmp4, Address(z, idx, Address::uxtw(LogBytesPerInt)));
add2_with_carry(carry2, tmp3, tmp4, carry);
strw(tmp3, Address(z, idx, Address::uxtw(LogBytesPerInt)));
extr(carry, carry2, tmp3, 32);
bind(L_post_third_loop_done);
}
/**
* Code for BigInteger::multiplyToLen() instrinsic.
*
* r0: x
* r1: xlen
* r2: y
* r3: ylen
* r4: z
* r5: zlen
* r10: tmp1
* r11: tmp2
* r12: tmp3
* r13: tmp4
* r14: tmp5
* r15: tmp6
* r16: tmp7
*
*/
void MacroAssembler::multiply_to_len(Register x, Register xlen, Register y, Register ylen,
Register z, Register zlen,
Register tmp1, Register tmp2, Register tmp3, Register tmp4,
Register tmp5, Register tmp6, Register product_hi) {
assert_different_registers(x, xlen, y, ylen, z, zlen, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6);
const Register idx = tmp1;
const Register kdx = tmp2;
const Register xstart = tmp3;
const Register y_idx = tmp4;
const Register carry = tmp5;
const Register product = xlen;
const Register x_xstart = zlen; // reuse register
// 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;
//
movw(idx, ylen); // idx = ylen;
movw(kdx, zlen); // kdx = xlen+ylen;
mov(carry, zr); // carry = 0;
Label L_done;
movw(xstart, xlen);
subsw(xstart, xstart, 1);
br(Assembler::MI, L_done);
multiply_64_x_64_loop(x, xstart, x_xstart, y, y_idx, z, carry, product, idx, kdx);
Label L_second_loop;
cbzw(kdx, L_second_loop);
Label L_carry;
subw(kdx, kdx, 1);
cbzw(kdx, L_carry);
strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
lsr(carry, carry, 32);
subw(kdx, kdx, 1);
bind(L_carry);
strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
// 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] = product_hi
const Register jdx = tmp1;
bind(L_second_loop);
mov(carry, zr); // carry = 0;
movw(jdx, ylen); // j = ystart+1
subsw(xstart, xstart, 1); // i = xstart-1;
br(Assembler::MI, L_done);
str(z, Address(pre(sp, -4 * wordSize)));
Label L_last_x;
lea(z, offsetted_address(z, xstart, Address::uxtw(LogBytesPerInt), 4, BytesPerInt)); // z = z + k - j
subsw(xstart, xstart, 1); // i = xstart-1;
br(Assembler::MI, L_last_x);
lea(rscratch1, Address(x, xstart, Address::uxtw(LogBytesPerInt)));
ldr(product_hi, Address(rscratch1));
ror(product_hi, product_hi, 32); // convert big-endian to little-endian
Label L_third_loop_prologue;
bind(L_third_loop_prologue);
str(ylen, Address(sp, wordSize));
stp(x, xstart, Address(sp, 2 * wordSize));
multiply_128_x_128_loop(y, z, carry, x, jdx, ylen, product,
tmp2, x_xstart, tmp3, tmp4, tmp6, product_hi);
ldp(z, ylen, Address(post(sp, 2 * wordSize)));
ldp(x, xlen, Address(post(sp, 2 * wordSize))); // copy old xstart -> xlen
addw(tmp3, xlen, 1);
strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
subsw(tmp3, tmp3, 1);
br(Assembler::MI, L_done);
lsr(carry, carry, 32);
strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
b(L_second_loop);
// Next infrequent code is moved outside loops.
bind(L_last_x);
ldrw(product_hi, Address(x, 0));
b(L_third_loop_prologue);
bind(L_done);
}
/**
* 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) {
eor(val, val, crc);
andr(val, val, 0xff);
ldrw(val, Address(table, val, Address::lsl(2)));
eor(crc, val, crc, Assembler::LSR, 8);
}
/**
* Emits code to update CRC-32 with a 32-bit value according to tables 0 to 3
*
* @param [in,out]crc Register containing the crc.
* @param [in]v Register containing the 32-bit to fold into the CRC.
* @param [in]table0 Register containing table 0 of crc constants.
* @param [in]table1 Register containing table 1 of crc constants.
* @param [in]table2 Register containing table 2 of crc constants.
* @param [in]table3 Register containing table 3 of crc constants.
*
* uint32_t crc;
* v = crc ^ v
* crc = table3[v&0xff]^table2[(v>>8)&0xff]^table1[(v>>16)&0xff]^table0[v>>24]
*
*/
void MacroAssembler::update_word_crc32(Register crc, Register v, Register tmp,
Register table0, Register table1, Register table2, Register table3,
bool upper) {
eor(v, crc, v, upper ? LSR:LSL, upper ? 32:0);
uxtb(tmp, v);
ldrw(crc, Address(table3, tmp, Address::lsl(2)));
ubfx(tmp, v, 8, 8);
ldrw(tmp, Address(table2, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
ubfx(tmp, v, 16, 8);
ldrw(tmp, Address(table1, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
ubfx(tmp, v, 24, 8);
ldrw(tmp, Address(table0, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
}
/**
* @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 that will contain address of CRC table
* @param tmp scratch register
*/
void MacroAssembler::kernel_crc32(Register crc, Register buf, Register len,
Register table0, Register table1, Register table2, Register table3,
Register tmp, Register tmp2, Register tmp3) {
Label L_by16, L_by16_loop, L_by4, L_by4_loop, L_by1, L_by1_loop, L_exit;
unsigned long offset;
ornw(crc, zr, crc);
if (UseCRC32) {
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop;
subs(len, len, 64);
br(Assembler::GE, CRC_by64_loop);
adds(len, len, 64-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp, Address(post(buf, 4)));
subs(len, len, 4);
crc32w(crc, crc, tmp);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp, Address(post(buf, 1)));
subs(len, len, 1);
crc32b(crc, crc, tmp);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32x(crc, crc, tmp);
crc32x(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32x(crc, crc, tmp);
crc32x(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32x(crc, crc, tmp);
crc32x(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32x(crc, crc, tmp);
crc32x(crc, crc, tmp3);
br(Assembler::GE, CRC_by64_loop);
adds(len, len, 64-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
BIND(L_exit);
ornw(crc, zr, crc);
return;
}
adrp(table0, ExternalAddress(StubRoutines::crc_table_addr()), offset);
if (offset) add(table0, table0, offset);
add(table1, table0, 1*256*sizeof(juint));
add(table2, table0, 2*256*sizeof(juint));
add(table3, table0, 3*256*sizeof(juint));
if (UseNeon) {
cmp(len, 64);
br(Assembler::LT, L_by16);
eor(v16, T16B, v16, v16);
Label L_fold;
add(tmp, table0, 4*256*sizeof(juint)); // Point at the Neon constants
ld1(v0, v1, T2D, post(buf, 32));
ld1r(v4, T2D, post(tmp, 8));
ld1r(v5, T2D, post(tmp, 8));
ld1r(v6, T2D, post(tmp, 8));
ld1r(v7, T2D, post(tmp, 8));
mov(v16, T4S, 0, crc);
eor(v0, T16B, v0, v16);
sub(len, len, 64);
BIND(L_fold);
pmull(v22, T8H, v0, v5, T8B);
pmull(v20, T8H, v0, v7, T8B);
pmull(v23, T8H, v0, v4, T8B);
pmull(v21, T8H, v0, v6, T8B);
pmull2(v18, T8H, v0, v5, T16B);
pmull2(v16, T8H, v0, v7, T16B);
pmull2(v19, T8H, v0, v4, T16B);
pmull2(v17, T8H, v0, v6, T16B);
uzp1(v24, v20, v22, T8H);
uzp2(v25, v20, v22, T8H);
eor(v20, T16B, v24, v25);
uzp1(v26, v16, v18, T8H);
uzp2(v27, v16, v18, T8H);
eor(v16, T16B, v26, v27);
ushll2(v22, T4S, v20, T8H, 8);
ushll(v20, T4S, v20, T4H, 8);
ushll2(v18, T4S, v16, T8H, 8);
ushll(v16, T4S, v16, T4H, 8);
eor(v22, T16B, v23, v22);
eor(v18, T16B, v19, v18);
eor(v20, T16B, v21, v20);
eor(v16, T16B, v17, v16);
uzp1(v17, v16, v20, T2D);
uzp2(v21, v16, v20, T2D);
eor(v17, T16B, v17, v21);
ushll2(v20, T2D, v17, T4S, 16);
ushll(v16, T2D, v17, T2S, 16);
eor(v20, T16B, v20, v22);
eor(v16, T16B, v16, v18);
uzp1(v17, v20, v16, T2D);
uzp2(v21, v20, v16, T2D);
eor(v28, T16B, v17, v21);
pmull(v22, T8H, v1, v5, T8B);
pmull(v20, T8H, v1, v7, T8B);
pmull(v23, T8H, v1, v4, T8B);
pmull(v21, T8H, v1, v6, T8B);
pmull2(v18, T8H, v1, v5, T16B);
pmull2(v16, T8H, v1, v7, T16B);
pmull2(v19, T8H, v1, v4, T16B);
pmull2(v17, T8H, v1, v6, T16B);
ld1(v0, v1, T2D, post(buf, 32));
uzp1(v24, v20, v22, T8H);
uzp2(v25, v20, v22, T8H);
eor(v20, T16B, v24, v25);
uzp1(v26, v16, v18, T8H);
uzp2(v27, v16, v18, T8H);
eor(v16, T16B, v26, v27);
ushll2(v22, T4S, v20, T8H, 8);
ushll(v20, T4S, v20, T4H, 8);
ushll2(v18, T4S, v16, T8H, 8);
ushll(v16, T4S, v16, T4H, 8);
eor(v22, T16B, v23, v22);
eor(v18, T16B, v19, v18);
eor(v20, T16B, v21, v20);
eor(v16, T16B, v17, v16);
uzp1(v17, v16, v20, T2D);
uzp2(v21, v16, v20, T2D);
eor(v16, T16B, v17, v21);
ushll2(v20, T2D, v16, T4S, 16);
ushll(v16, T2D, v16, T2S, 16);
eor(v20, T16B, v22, v20);
eor(v16, T16B, v16, v18);
uzp1(v17, v20, v16, T2D);
uzp2(v21, v20, v16, T2D);
eor(v20, T16B, v17, v21);
shl(v16, T2D, v28, 1);
shl(v17, T2D, v20, 1);
eor(v0, T16B, v0, v16);
eor(v1, T16B, v1, v17);
subs(len, len, 32);
br(Assembler::GE, L_fold);
mov(crc, 0);
mov(tmp, v0, T1D, 0);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v0, T1D, 1);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v1, T1D, 0);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v1, T1D, 1);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
add(len, len, 32);
}
BIND(L_by16);
subs(len, len, 16);
br(Assembler::GE, L_by16_loop);
adds(len, len, 16-4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::GT, L_by1_loop);
b(L_exit);
BIND(L_by4_loop);
ldrw(tmp, Address(post(buf, 4)));
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3);
subs(len, len, 4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(L_by1_loop);
subs(len, len, 1);
ldrb(tmp, Address(post(buf, 1)));
update_byte_crc32(crc, tmp, table0);
br(Assembler::GT, L_by1_loop);
b(L_exit);
align(CodeEntryAlignment);
BIND(L_by16_loop);
subs(len, len, 16);
ldp(tmp, tmp3, Address(post(buf, 16)));
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, true);
br(Assembler::GE, L_by16_loop);
adds(len, len, 16-4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::GT, L_by1_loop);
BIND(L_exit);
ornw(crc, zr, 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 that will contain address of CRC table
* @param tmp scratch register
*/
void MacroAssembler::kernel_crc32c(Register crc, Register buf, Register len,
Register table0, Register table1, Register table2, Register table3,
Register tmp, Register tmp2, Register tmp3) {
Label L_exit;
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop;
subs(len, len, 64);
br(Assembler::GE, CRC_by64_loop);
adds(len, len, 64-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp, Address(post(buf, 4)));
subs(len, len, 4);
crc32cw(crc, crc, tmp);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp, Address(post(buf, 1)));
subs(len, len, 1);
crc32cb(crc, crc, tmp);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32cx(crc, crc, tmp);
crc32cx(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32cx(crc, crc, tmp);
crc32cx(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32cx(crc, crc, tmp);
crc32cx(crc, crc, tmp3);
ldp(tmp, tmp3, Address(post(buf, 16)));
crc32cx(crc, crc, tmp);
crc32cx(crc, crc, tmp3);
br(Assembler::GE, CRC_by64_loop);
adds(len, len, 64-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
BIND(L_exit);
return;
}
SkipIfEqual::SkipIfEqual(
MacroAssembler* masm, const bool* flag_addr, bool value) {
_masm = masm;
unsigned long offset;
_masm->adrp(rscratch1, ExternalAddress((address)flag_addr), offset);
_masm->ldrb(rscratch1, Address(rscratch1, offset));
_masm->cbzw(rscratch1, _label);
}
SkipIfEqual::~SkipIfEqual() {
_masm->bind(_label);
}
void MacroAssembler::addptr(const Address &dst, int32_t src) {
Address adr;
switch(dst.getMode()) {
case Address::base_plus_offset:
// This is the expected mode, although we allow all the other
// forms below.
adr = form_address(rscratch2, dst.base(), dst.offset(), LogBytesPerWord);
break;
default:
lea(rscratch2, dst);
adr = Address(rscratch2);
break;
}
ldr(rscratch1, adr);
add(rscratch1, rscratch1, src);
str(rscratch1, adr);
}
void MacroAssembler::cmpptr(Register src1, Address src2) {
unsigned long offset;
adrp(rscratch1, src2, offset);
ldr(rscratch1, Address(rscratch1, offset));
cmp(src1, rscratch1);
}
void MacroAssembler::store_check(Register obj, Address dst) {
store_check(obj);
}
void MacroAssembler::store_check(Register obj) {
// Does a store check for the oop in register obj. The content of
// register obj is destroyed afterwards.
BarrierSet* bs = Universe::heap()->barrier_set();
assert(bs->kind() == BarrierSet::CardTableForRS ||
bs->kind() == BarrierSet::CardTableExtension,
"Wrong barrier set kind");
CardTableModRefBS* ct = barrier_set_cast<CardTableModRefBS>(bs);
assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");
lsr(obj, obj, CardTableModRefBS::card_shift);
assert(CardTableModRefBS::dirty_card_val() == 0, "must be");
load_byte_map_base(rscratch1);
if (UseCondCardMark) {
Label L_already_dirty;
membar(StoreLoad);
ldrb(rscratch2, Address(obj, rscratch1));
cbz(rscratch2, L_already_dirty);
strb(zr, Address(obj, rscratch1));
bind(L_already_dirty);
} else {
if (UseConcMarkSweepGC && CMSPrecleaningEnabled) {
membar(StoreStore);
}
strb(zr, Address(obj, rscratch1));
}
}
void MacroAssembler::load_klass(Register dst, Register src) {
if (UseCompressedClassPointers) {
ldrw(dst, Address(src, oopDesc::klass_offset_in_bytes()));
decode_klass_not_null(dst);
} else {
ldr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
}
}
void MacroAssembler::cmp_klass(Register oop, Register trial_klass, Register tmp) {
if (UseCompressedClassPointers) {
ldrw(tmp, Address(oop, oopDesc::klass_offset_in_bytes()));
if (Universe::narrow_klass_base() == NULL) {
cmp(trial_klass, tmp, LSL, Universe::narrow_klass_shift());
return;
} else if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
&& Universe::narrow_klass_shift() == 0) {
// Only the bottom 32 bits matter
cmpw(trial_klass, tmp);
return;
}
decode_klass_not_null(tmp);
} else {
ldr(tmp, Address(oop, oopDesc::klass_offset_in_bytes()));
}
cmp(trial_klass, tmp);
}
void MacroAssembler::load_prototype_header(Register dst, Register src) {
load_klass(dst, src);
ldr(dst, Address(dst, Klass::prototype_header_offset()));
}
void MacroAssembler::store_klass(Register dst, Register src) {
// FIXME: Should this be a store release? concurrent gcs assumes
// klass length is valid if klass field is not null.
if (UseCompressedClassPointers) {
encode_klass_not_null(src);
strw(src, Address(dst, oopDesc::klass_offset_in_bytes()));
} else {
str(src, Address(dst, oopDesc::klass_offset_in_bytes()));
}
}
void MacroAssembler::store_klass_gap(Register dst, Register src) {
if (UseCompressedClassPointers) {
// Store to klass gap in destination
strw(src, Address(dst, oopDesc::klass_gap_offset_in_bytes()));
}
}
// Algorithm must match oop.inline.hpp encode_heap_oop.
void MacroAssembler::encode_heap_oop(Register d, Register s) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop: heap base corrupted?");
#endif
verify_oop(s, "broken oop in encode_heap_oop");
if (Universe::narrow_oop_base() == NULL) {
if (Universe::narrow_oop_shift() != 0) {
assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
lsr(d, s, LogMinObjAlignmentInBytes);
} else {
mov(d, s);
}
} else {
subs(d, s, rheapbase);
csel(d, d, zr, Assembler::HS);
lsr(d, d, LogMinObjAlignmentInBytes);
/* Old algorithm: is this any worse?
Label nonnull;
cbnz(r, nonnull);
sub(r, r, rheapbase);
bind(nonnull);
lsr(r, r, LogMinObjAlignmentInBytes);
*/
}
}
void MacroAssembler::encode_heap_oop_not_null(Register r) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop_not_null: heap base corrupted?");
if (CheckCompressedOops) {
Label ok;
cbnz(r, ok);
stop("null oop passed to encode_heap_oop_not_null");
bind(ok);
}
#endif
verify_oop(r, "broken oop in encode_heap_oop_not_null");
if (Universe::narrow_oop_base() != NULL) {
sub(r, r, rheapbase);
}
if (Universe::narrow_oop_shift() != 0) {
assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
lsr(r, r, LogMinObjAlignmentInBytes);
}
}
void MacroAssembler::encode_heap_oop_not_null(Register dst, Register src) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop_not_null2: heap base corrupted?");
if (CheckCompressedOops) {
Label ok;
cbnz(src, ok);
stop("null oop passed to encode_heap_oop_not_null2");
bind(ok);
}
#endif
verify_oop(src, "broken oop in encode_heap_oop_not_null2");
Register data = src;
if (Universe::narrow_oop_base() != NULL) {
sub(dst, src, rheapbase);
data = dst;
}
if (Universe::narrow_oop_shift() != 0) {
assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
lsr(dst, data, LogMinObjAlignmentInBytes);
data = dst;
}
if (data == src)
mov(dst, src);
}
void MacroAssembler::decode_heap_oop(Register d, Register s) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::decode_heap_oop: heap base corrupted?");
#endif
if (Universe::narrow_oop_base() == NULL) {
if (Universe::narrow_oop_shift() != 0 || d != s) {
lsl(d, s, Universe::narrow_oop_shift());
}
} else {
Label done;
if (d != s)
mov(d, s);
cbz(s, done);
add(d, rheapbase, s, Assembler::LSL, LogMinObjAlignmentInBytes);
bind(done);
}
verify_oop(d, "broken oop in decode_heap_oop");
}
void MacroAssembler::decode_heap_oop_not_null(Register r) {
assert (UseCompressedOops, "should only be used for compressed headers");
assert (Universe::heap() != NULL, "java heap should be initialized");
// Cannot assert, unverified entry point counts instructions (see .ad file)
// vtableStubs also counts instructions in pd_code_size_limit.
// Also do not verify_oop as this is called by verify_oop.
if (Universe::narrow_oop_shift() != 0) {
assert(LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
if (Universe::narrow_oop_base() != NULL) {
add(r, rheapbase, r, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(r, zr, r, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (Universe::narrow_oop_base() == NULL, "sanity");
}
}
void MacroAssembler::decode_heap_oop_not_null(Register dst, Register src) {
assert (UseCompressedOops, "should only be used for compressed headers");
assert (Universe::heap() != NULL, "java heap should be initialized");
// Cannot assert, unverified entry point counts instructions (see .ad file)
// vtableStubs also counts instructions in pd_code_size_limit.
// Also do not verify_oop as this is called by verify_oop.
if (Universe::narrow_oop_shift() != 0) {
assert(LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
if (Universe::narrow_oop_base() != NULL) {
add(dst, rheapbase, src, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(dst, zr, src, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (Universe::narrow_oop_base() == NULL, "sanity");
if (dst != src) {
mov(dst, src);
}
}
}
void MacroAssembler::encode_klass_not_null(Register dst, Register src) {
if (Universe::narrow_klass_base() == NULL) {
if (Universe::narrow_klass_shift() != 0) {
assert (LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
lsr(dst, src, LogKlassAlignmentInBytes);
} else {
if (dst != src) mov(dst, src);
}
return;
}
if (use_XOR_for_compressed_class_base) {
if (Universe::narrow_klass_shift() != 0) {
eor(dst, src, (uint64_t)Universe::narrow_klass_base());
lsr(dst, dst, LogKlassAlignmentInBytes);
} else {
eor(dst, src, (uint64_t)Universe::narrow_klass_base());
}
return;
}
if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
&& Universe::narrow_klass_shift() == 0) {
movw(dst, src);
return;
}
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_klass_not_null2: heap base corrupted?");
#endif
Register rbase = dst;
if (dst == src) rbase = rheapbase;
mov(rbase, (uint64_t)Universe::narrow_klass_base());
sub(dst, src, rbase);
if (Universe::narrow_klass_shift() != 0) {
assert (LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
lsr(dst, dst, LogKlassAlignmentInBytes);
}
if (dst == src) reinit_heapbase();
}
void MacroAssembler::encode_klass_not_null(Register r) {
encode_klass_not_null(r, r);
}
void MacroAssembler::decode_klass_not_null(Register dst, Register src) {
Register rbase = dst;
assert (UseCompressedClassPointers, "should only be used for compressed headers");
if (Universe::narrow_klass_base() == NULL) {
if (Universe::narrow_klass_shift() != 0) {
assert(LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
lsl(dst, src, LogKlassAlignmentInBytes);
} else {
if (dst != src) mov(dst, src);
}
return;
}
if (use_XOR_for_compressed_class_base) {
if (Universe::narrow_klass_shift() != 0) {
lsl(dst, src, LogKlassAlignmentInBytes);
eor(dst, dst, (uint64_t)Universe::narrow_klass_base());
} else {
eor(dst, src, (uint64_t)Universe::narrow_klass_base());
}
return;
}
if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
&& Universe::narrow_klass_shift() == 0) {
if (dst != src)
movw(dst, src);
movk(dst, (uint64_t)Universe::narrow_klass_base() >> 32, 32);
return;
}
// Cannot assert, unverified entry point counts instructions (see .ad file)
// vtableStubs also counts instructions in pd_code_size_limit.
// Also do not verify_oop as this is called by verify_oop.
if (dst == src) rbase = rheapbase;
mov(rbase, (uint64_t)Universe::narrow_klass_base());
if (Universe::narrow_klass_shift() != 0) {
assert(LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
add(dst, rbase, src, Assembler::LSL, LogKlassAlignmentInBytes);
} else {
add(dst, rbase, src);
}
if (dst == src) reinit_heapbase();
}
void MacroAssembler::decode_klass_not_null(Register r) {
decode_klass_not_null(r, r);
}
void MacroAssembler::set_narrow_oop(Register dst, jobject obj) {
assert (UseCompressedOops, "should only be used for compressed oops");
assert (Universe::heap() != NULL, "java heap should be initialized");
assert (oop_recorder() != NULL, "this assembler needs an OopRecorder");
int oop_index = oop_recorder()->find_index(obj);
assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "should be real oop");
InstructionMark im(this);
RelocationHolder rspec = oop_Relocation::spec(oop_index);
code_section()->relocate(inst_mark(), rspec);
movz(dst, 0xDEAD, 16);
movk(dst, 0xBEEF);
}
void MacroAssembler::set_narrow_klass(Register dst, Klass* k) {
assert (UseCompressedClassPointers, "should only be used for compressed headers");
assert (oop_recorder() != NULL, "this assembler needs an OopRecorder");
int index = oop_recorder()->find_index(k);
assert(! Universe::heap()->is_in_reserved(k), "should not be an oop");
InstructionMark im(this);
RelocationHolder rspec = metadata_Relocation::spec(index);
code_section()->relocate(inst_mark(), rspec);
narrowKlass nk = Klass::encode_klass(k);
movz(dst, (nk >> 16), 16);
movk(dst, nk & 0xffff);
}
void MacroAssembler::load_heap_oop(Register dst, Address src)
{
if (UseCompressedOops) {
ldrw(dst, src);
decode_heap_oop(dst);
} else {
ldr(dst, src);
}
}
void MacroAssembler::load_heap_oop_not_null(Register dst, Address src)
{
if (UseCompressedOops) {
ldrw(dst, src);
decode_heap_oop_not_null(dst);
} else {
ldr(dst, src);
}
}
void MacroAssembler::store_heap_oop(Address dst, Register src) {
if (UseCompressedOops) {
assert(!dst.uses(src), "not enough registers");
encode_heap_oop(src);
strw(src, dst);
} else
str(src, dst);
}
// Used for storing NULLs.
void MacroAssembler::store_heap_oop_null(Address dst) {
if (UseCompressedOops) {
strw(zr, dst);
} else
str(zr, dst);
}
#if INCLUDE_ALL_GCS
void MacroAssembler::g1_write_barrier_pre(Register obj,
Register pre_val,
Register thread,
Register tmp,
bool tosca_live,
bool expand_call) {
// If expand_call is true then we expand the call_VM_leaf macro
// directly to skip generating the check by
// InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
assert(thread == rthread, "must be");
Label done;
Label runtime;
assert(pre_val != noreg, "check this code");
if (obj != noreg)
assert_different_registers(obj, pre_val, tmp);
Address in_progress(thread, in_bytes(JavaThread::satb_mark_queue_offset() +
SATBMarkQueue::byte_offset_of_active()));
Address index(thread, in_bytes(JavaThread::satb_mark_queue_offset() +
SATBMarkQueue::byte_offset_of_index()));
Address buffer(thread, in_bytes(JavaThread::satb_mark_queue_offset() +
SATBMarkQueue::byte_offset_of_buf()));
// Is marking active?
if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
ldrw(tmp, in_progress);
} else {
assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
ldrb(tmp, in_progress);
}
cbzw(tmp, done);
// Do we need to load the previous value?
if (obj != noreg) {
load_heap_oop(pre_val, Address(obj, 0));
}
// Is the previous value null?
cbz(pre_val, done);
// Can we store original value in the thread's buffer?
// Is index == 0?
// (The index field is typed as size_t.)
ldr(tmp, index); // tmp := *index_adr
cbz(tmp, runtime); // tmp == 0?
// If yes, goto runtime
sub(tmp, tmp, wordSize); // tmp := tmp - wordSize
str(tmp, index); // *index_adr := tmp
ldr(rscratch1, buffer);
add(tmp, tmp, rscratch1); // tmp := tmp + *buffer_adr
// Record the previous value
str(pre_val, Address(tmp, 0));
b(done);
bind(runtime);
// save the live input values
push(r0->bit(tosca_live) | obj->bit(obj != noreg) | pre_val->bit(true), sp);
// Calling the runtime using the regular call_VM_leaf mechanism generates
// code (generated by InterpreterMacroAssember::call_VM_leaf_base)
// that checks that the *(rfp+frame::interpreter_frame_last_sp) == NULL.
//
// If we care generating the pre-barrier without a frame (e.g. in the
// intrinsified Reference.get() routine) then ebp might be pointing to
// the caller frame and so this check will most likely fail at runtime.
//
// Expanding the call directly bypasses the generation of the check.
// So when we do not have have a full interpreter frame on the stack
// expand_call should be passed true.
if (expand_call) {
assert(pre_val != c_rarg1, "smashed arg");
pass_arg1(this, thread);
pass_arg0(this, pre_val);
MacroAssembler::call_VM_leaf_base(CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), 2);
} else {
call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), pre_val, thread);
}
pop(r0->bit(tosca_live) | obj->bit(obj != noreg) | pre_val->bit(true), sp);
bind(done);
}
void MacroAssembler::g1_write_barrier_post(Register store_addr,
Register new_val,
Register thread,
Register tmp,
Register tmp2) {
assert(thread == rthread, "must be");
Address queue_index(thread, in_bytes(JavaThread::dirty_card_queue_offset() +
DirtyCardQueue::byte_offset_of_index()));
Address buffer(thread, in_bytes(JavaThread::dirty_card_queue_offset() +
DirtyCardQueue::byte_offset_of_buf()));
BarrierSet* bs = Universe::heap()->barrier_set();
CardTableModRefBS* ct = (CardTableModRefBS*)bs;
assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");
Label done;
Label runtime;
// Does store cross heap regions?
eor(tmp, store_addr, new_val);
lsr(tmp, tmp, HeapRegion::LogOfHRGrainBytes);
cbz(tmp, done);
// crosses regions, storing NULL?
cbz(new_val, done);
// storing region crossing non-NULL, is card already dirty?
ExternalAddress cardtable((address) ct->byte_map_base);
assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");
const Register card_addr = tmp;
lsr(card_addr, store_addr, CardTableModRefBS::card_shift);
// get the address of the card
load_byte_map_base(tmp2);
add(card_addr, card_addr, tmp2);
ldrb(tmp2, Address(card_addr));
cmpw(tmp2, (int)G1SATBCardTableModRefBS::g1_young_card_val());
br(Assembler::EQ, done);
assert((int)CardTableModRefBS::dirty_card_val() == 0, "must be 0");
membar(Assembler::StoreLoad);
ldrb(tmp2, Address(card_addr));
cbzw(tmp2, done);
// storing a region crossing, non-NULL oop, card is clean.
// dirty card and log.
strb(zr, Address(card_addr));
ldr(rscratch1, queue_index);
cbz(rscratch1, runtime);
sub(rscratch1, rscratch1, wordSize);
str(rscratch1, queue_index);
ldr(tmp2, buffer);
str(card_addr, Address(tmp2, rscratch1));
b(done);
bind(runtime);
// save the live input values
push(store_addr->bit(true) | new_val->bit(true), sp);
call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), card_addr, thread);
pop(store_addr->bit(true) | new_val->bit(true), sp);
bind(done);
}
#endif // INCLUDE_ALL_GCS
Address MacroAssembler::allocate_metadata_address(Metadata* obj) {
assert(oop_recorder() != NULL, "this assembler needs a Recorder");
int index = oop_recorder()->allocate_metadata_index(obj);
RelocationHolder rspec = metadata_Relocation::spec(index);
return Address((address)obj, rspec);
}
// Move an oop into a register. immediate is true if we want
// immediate instrcutions, i.e. we are not going to patch this
// instruction while the code is being executed by another thread. In
// that case we can use move immediates rather than the constant pool.
void MacroAssembler::movoop(Register dst, jobject obj, bool immediate) {
int oop_index;
if (obj == NULL) {
oop_index = oop_recorder()->allocate_oop_index(obj);
} else {
oop_index = oop_recorder()->find_index(obj);
assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "should be real oop");
}
RelocationHolder rspec = oop_Relocation::spec(oop_index);
if (! immediate) {
address dummy = address(uintptr_t(pc()) & -wordSize); // A nearby aligned address
ldr_constant(dst, Address(dummy, rspec));
} else
mov(dst, Address((address)obj, rspec));
}
// Move a metadata address into a register.
void MacroAssembler::mov_metadata(Register dst, Metadata* obj) {
int oop_index;
if (obj == NULL) {
oop_index = oop_recorder()->allocate_metadata_index(obj);
} else {
oop_index = oop_recorder()->find_index(obj);
}
RelocationHolder rspec = metadata_Relocation::spec(oop_index);
mov(dst, Address((address)obj, rspec));
}
Address MacroAssembler::constant_oop_address(jobject obj) {
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "not an oop");
int oop_index = oop_recorder()->find_index(obj);
return Address((address)obj, oop_Relocation::spec(oop_index));
}
// 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,
Register t2,
Label& slow_case) {
assert_different_registers(obj, t2);
assert_different_registers(obj, var_size_in_bytes);
Register end = t2;
// verify_tlab();
ldr(obj, Address(rthread, JavaThread::tlab_top_offset()));
if (var_size_in_bytes == noreg) {
lea(end, Address(obj, con_size_in_bytes));
} else {
lea(end, Address(obj, var_size_in_bytes));
}
ldr(rscratch1, Address(rthread, JavaThread::tlab_end_offset()));
cmp(end, rscratch1);
br(Assembler::HI, slow_case);
// update the tlab top pointer
str(end, Address(rthread, JavaThread::tlab_top_offset()));
// recover var_size_in_bytes if necessary
if (var_size_in_bytes == end) {
sub(var_size_in_bytes, var_size_in_bytes, obj);
}
// verify_tlab();
}
// Preserves r19, and r3.
Register MacroAssembler::tlab_refill(Label& retry,
Label& try_eden,
Label& slow_case) {
Register top = r0;
Register t1 = r2;
Register t2 = r4;
assert_different_registers(top, rthread, t1, t2, /* preserve: */ r19, r3);
Label do_refill, discard_tlab;
if (!Universe::heap()->supports_inline_contig_alloc()) {
// No allocation in the shared eden.
b(slow_case);
}
ldr(top, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
ldr(t1, Address(rthread, in_bytes(JavaThread::tlab_end_offset())));
// calculate amount of free space
sub(t1, t1, top);
lsr(t1, t1, LogHeapWordSize);
// Retain tlab and allocate object in shared space if
// the amount free in the tlab is too large to discard.
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_refill_waste_limit_offset())));
cmp(t1, rscratch1);
br(Assembler::LE, discard_tlab);
// Retain
// ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_refill_waste_limit_offset())));
mov(t2, (int32_t) ThreadLocalAllocBuffer::refill_waste_limit_increment());
add(rscratch1, rscratch1, t2);
str(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_refill_waste_limit_offset())));
if (TLABStats) {
// increment number of slow_allocations
addmw(Address(rthread, in_bytes(JavaThread::tlab_slow_allocations_offset())),
1, rscratch1);
}
b(try_eden);
bind(discard_tlab);
if (TLABStats) {
// increment number of refills
addmw(Address(rthread, in_bytes(JavaThread::tlab_number_of_refills_offset())), 1,
rscratch1);
// accumulate wastage -- t1 is amount free in tlab
addmw(Address(rthread, in_bytes(JavaThread::tlab_fast_refill_waste_offset())), t1,
rscratch1);
}
// if tlab is currently allocated (top or end != null) then
// fill [top, end + alignment_reserve) with array object
cbz(top, do_refill);
// set up the mark word
mov(rscratch1, (intptr_t)markOopDesc::prototype()->copy_set_hash(0x2));
str(rscratch1, Address(top, oopDesc::mark_offset_in_bytes()));
// set the length to the remaining space
sub(t1, t1, typeArrayOopDesc::header_size(T_INT));
add(t1, t1, (int32_t)ThreadLocalAllocBuffer::alignment_reserve());
lsl(t1, t1, log2_intptr(HeapWordSize/sizeof(jint)));
strw(t1, Address(top, arrayOopDesc::length_offset_in_bytes()));
// set klass to intArrayKlass
{
unsigned long offset;
// dubious reloc why not an oop reloc?
adrp(rscratch1, ExternalAddress((address)Universe::intArrayKlassObj_addr()),
offset);
ldr(t1, Address(rscratch1, offset));
}
// store klass last. concurrent gcs assumes klass length is valid if
// klass field is not null.
store_klass(top, t1);
mov(t1, top);
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_start_offset())));
sub(t1, t1, rscratch1);
incr_allocated_bytes(rthread, t1, 0, rscratch1);
// refill the tlab with an eden allocation
bind(do_refill);
ldr(t1, Address(rthread, in_bytes(JavaThread::tlab_size_offset())));
lsl(t1, t1, LogHeapWordSize);
// allocate new tlab, address returned in top
eden_allocate(top, t1, 0, t2, slow_case);
// Check that t1 was preserved in eden_allocate.
#ifdef ASSERT
if (UseTLAB) {
Label ok;
Register tsize = r4;
assert_different_registers(tsize, rthread, t1);
str(tsize, Address(pre(sp, -16)));
ldr(tsize, Address(rthread, in_bytes(JavaThread::tlab_size_offset())));
lsl(tsize, tsize, LogHeapWordSize);
cmp(t1, tsize);
br(Assembler::EQ, ok);
STOP("assert(t1 != tlab size)");
should_not_reach_here();
bind(ok);
ldr(tsize, Address(post(sp, 16)));
}
#endif
str(top, Address(rthread, in_bytes(JavaThread::tlab_start_offset())));
str(top, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
add(top, top, t1);
sub(top, top, (int32_t)ThreadLocalAllocBuffer::alignment_reserve_in_bytes());
str(top, Address(rthread, in_bytes(JavaThread::tlab_end_offset())));
verify_tlab();
b(retry);
return rthread; // for use by caller
}
// Defines obj, preserves var_size_in_bytes
void MacroAssembler::eden_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);
if (!Universe::heap()->supports_inline_contig_alloc()) {
b(slow_case);
} else {
Register end = t1;
Register heap_end = rscratch2;
Label retry;
bind(retry);
{
unsigned long offset;
adrp(rscratch1, ExternalAddress((address) Universe::heap()->end_addr()), offset);
ldr(heap_end, Address(rscratch1, offset));
}
ExternalAddress heap_top((address) Universe::heap()->top_addr());
// Get the current top of the heap
{
unsigned long offset;
adrp(rscratch1, heap_top, offset);
// Use add() here after ARDP, rather than lea().
// lea() does not generate anything if its offset is zero.
// However, relocs expect to find either an ADD or a load/store
// insn after an ADRP. add() always generates an ADD insn, even
// for add(Rn, Rn, 0).
add(rscratch1, rscratch1, offset);
ldaxr(obj, rscratch1);
}
// Adjust it my the size of our new object
if (var_size_in_bytes == noreg) {
lea(end, Address(obj, con_size_in_bytes));
} else {
lea(end, Address(obj, var_size_in_bytes));
}
// if end < obj then we wrapped around high memory
cmp(end, obj);
br(Assembler::LO, slow_case);
cmp(end, heap_end);
br(Assembler::HI, slow_case);
// If heap_top hasn't been changed by some other thread, update it.
stlxr(rscratch2, end, rscratch1);
cbnzw(rscratch2, retry);
}
}
void MacroAssembler::verify_tlab() {
#ifdef ASSERT
if (UseTLAB && VerifyOops) {
Label next, ok;
stp(rscratch2, rscratch1, Address(pre(sp, -16)));
ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_start_offset())));
cmp(rscratch2, rscratch1);
br(Assembler::HS, next);
STOP("assert(top >= start)");
should_not_reach_here();
bind(next);
ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_end_offset())));
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
cmp(rscratch2, rscratch1);
br(Assembler::HS, ok);
STOP("assert(top <= end)");
should_not_reach_here();
bind(ok);
ldp(rscratch2, rscratch1, Address(post(sp, 16)));
}
#endif
}
// Writes to stack successive pages until offset reached to check for
// stack overflow + shadow pages. This clobbers tmp.
void MacroAssembler::bang_stack_size(Register size, Register tmp) {
assert_different_registers(tmp, size, rscratch1);
mov(tmp, sp);
// Bang stack for total size given plus shadow page size.
// Bang one page at a time because large size can bang beyond yellow and
// red zones.
Label loop;
mov(rscratch1, os::vm_page_size());
bind(loop);
lea(tmp, Address(tmp, -os::vm_page_size()));
subsw(size, size, rscratch1);
str(size, Address(tmp));
br(Assembler::GT, loop);
// Bang down shadow pages too.
// At this point, (tmp-0) is the last address touched, so don't
// touch it again. (It was touched as (tmp-pagesize) but then tmp
// was post-decremented.) Skip this address by starting at i=1, and
// touch a few more pages below. N.B. It is important to touch all
// the way down to and including i=StackShadowPages.
for (int i = 0; i < (int)(JavaThread::stack_shadow_zone_size() / os::vm_page_size()) - 1; i++) {
// this could be any sized move but this is can be a debugging crumb
// so the bigger the better.
lea(tmp, Address(tmp, -os::vm_page_size()));
str(size, Address(tmp));
}
}
address MacroAssembler::read_polling_page(Register r, address page, relocInfo::relocType rtype) {
unsigned long off;
adrp(r, Address(page, rtype), off);
InstructionMark im(this);
code_section()->relocate(inst_mark(), rtype);
ldrw(zr, Address(r, off));
return inst_mark();
}
address MacroAssembler::read_polling_page(Register r, relocInfo::relocType rtype) {
InstructionMark im(this);
code_section()->relocate(inst_mark(), rtype);
ldrw(zr, Address(r, 0));
return inst_mark();
}
void MacroAssembler::adrp(Register reg1, const Address &dest, unsigned long &byte_offset) {
relocInfo::relocType rtype = dest.rspec().reloc()->type();
unsigned long low_page = (unsigned long)CodeCache::low_bound() >> 12;
unsigned long high_page = (unsigned long)(CodeCache::high_bound()-1) >> 12;
unsigned long dest_page = (unsigned long)dest.target() >> 12;
long offset_low = dest_page - low_page;
long offset_high = dest_page - high_page;
assert(is_valid_AArch64_address(dest.target()), "bad address");
assert(dest.getMode() == Address::literal, "ADRP must be applied to a literal address");
InstructionMark im(this);
code_section()->relocate(inst_mark(), dest.rspec());
// 8143067: Ensure that the adrp can reach the dest from anywhere within
// the code cache so that if it is relocated we know it will still reach
if (offset_high >= -(1<<20) && offset_low < (1<<20)) {
_adrp(reg1, dest.target());
} else {
unsigned long target = (unsigned long)dest.target();
unsigned long adrp_target
= (target & 0xffffffffUL) | ((unsigned long)pc() & 0xffff00000000UL);
_adrp(reg1, (address)adrp_target);
movk(reg1, target >> 32, 32);
}
byte_offset = (unsigned long)dest.target() & 0xfff;
}
void MacroAssembler::load_byte_map_base(Register reg) {
jbyte *byte_map_base =
((CardTableModRefBS*)(Universe::heap()->barrier_set()))->byte_map_base;
if (is_valid_AArch64_address((address)byte_map_base)) {
// Strictly speaking the byte_map_base isn't an address at all,
// and it might even be negative.
unsigned long offset;
adrp(reg, ExternalAddress((address)byte_map_base), offset);
assert(offset == 0, "misaligned card table base");
} else {
mov(reg, (uint64_t)byte_map_base);
}
}
void MacroAssembler::build_frame(int framesize) {
assert(framesize > 0, "framesize must be > 0");
if (framesize < ((1 << 9) + 2 * wordSize)) {
sub(sp, sp, framesize);
stp(rfp, lr, Address(sp, framesize - 2 * wordSize));
if (PreserveFramePointer) add(rfp, sp, framesize - 2 * wordSize);
} else {
stp(rfp, lr, Address(pre(sp, -2 * wordSize)));
if (PreserveFramePointer) mov(rfp, sp);
if (framesize < ((1 << 12) + 2 * wordSize))
sub(sp, sp, framesize - 2 * wordSize);
else {
mov(rscratch1, framesize - 2 * wordSize);
sub(sp, sp, rscratch1);
}
}
}
void MacroAssembler::remove_frame(int framesize) {
assert(framesize > 0, "framesize must be > 0");
if (framesize < ((1 << 9) + 2 * wordSize)) {
ldp(rfp, lr, Address(sp, framesize - 2 * wordSize));
add(sp, sp, framesize);
} else {
if (framesize < ((1 << 12) + 2 * wordSize))
add(sp, sp, framesize - 2 * wordSize);
else {
mov(rscratch1, framesize - 2 * wordSize);
add(sp, sp, rscratch1);
}
ldp(rfp, lr, Address(post(sp, 2 * wordSize)));
}
}
// Search for str1 in str2 and return index or -1
void MacroAssembler::string_indexof(Register str2, Register str1,
Register cnt2, Register cnt1,
Register tmp1, Register tmp2,
Register tmp3, Register tmp4,
int icnt1, Register result) {
Label BM, LINEARSEARCH, DONE, NOMATCH, MATCH;
Register ch1 = rscratch1;
Register ch2 = rscratch2;
Register cnt1tmp = tmp1;
Register cnt2tmp = tmp2;
Register cnt1_neg = cnt1;
Register cnt2_neg = cnt2;
Register result_tmp = tmp4;
// Note, inline_string_indexOf() generates checks:
// if (substr.count > string.count) return -1;
// if (substr.count == 0) return 0;
// We have two strings, a source string in str2, cnt2 and a pattern string
// in str1, cnt1. Find the 1st occurence of pattern in source or return -1.
// For larger pattern and source we use a simplified Boyer Moore algorithm.
// With a small pattern and source we use linear scan.
if (icnt1 == -1) {
cmp(cnt1, 256); // Use Linear Scan if cnt1 < 8 || cnt1 >= 256
ccmp(cnt1, 8, 0b0000, LO); // Can't handle skip >= 256 because we use
br(LO, LINEARSEARCH); // a byte array.
cmp(cnt1, cnt2, LSR, 2); // Source must be 4 * pattern for BM
br(HS, LINEARSEARCH);
}
// The Boyer Moore alogorithm is based on the description here:-
//
// http://en.wikipedia.org/wiki/Boyer%E2%80%93Moore_string_search_algorithm
//
// This describes and algorithm with 2 shift rules. The 'Bad Character' rule
// and the 'Good Suffix' rule.
//
// These rules are essentially heuristics for how far we can shift the
// pattern along the search string.
//
// The implementation here uses the 'Bad Character' rule only because of the
// complexity of initialisation for the 'Good Suffix' rule.
//
// This is also known as the Boyer-Moore-Horspool algorithm:-
//
// http://en.wikipedia.org/wiki/Boyer-Moore-Horspool_algorithm
//
// #define ASIZE 128
//
// int bm(unsigned char *x, int m, unsigned char *y, int n) {
// int i, j;
// unsigned c;
// unsigned char bc[ASIZE];
//
// /* Preprocessing */
// for (i = 0; i < ASIZE; ++i)
// bc[i] = 0;
// for (i = 0; i < m - 1; ) {
// c = x[i];
// ++i;
// if (c < ASIZE) bc[c] = i;
// }
//
// /* Searching */
// j = 0;
// while (j <= n - m) {
// c = y[i+j];
// if (x[m-1] == c)
// for (i = m - 2; i >= 0 && x[i] == y[i + j]; --i);
// if (i < 0) return j;
// if (c < ASIZE)
// j = j - bc[y[j+m-1]] + m;
// else
// j += 1; // Advance by 1 only if char >= ASIZE
// }
// }
if (icnt1 == -1) {
BIND(BM);
Label ZLOOP, BCLOOP, BCSKIP, BMLOOPSTR2, BMLOOPSTR1, BMSKIP;
Label BMADV, BMMATCH, BMCHECKEND;
Register cnt1end = tmp2;
Register str2end = cnt2;
Register skipch = tmp2;
// Restrict ASIZE to 128 to reduce stack space/initialisation.
// The presence of chars >= ASIZE in the target string does not affect
// performance, but we must be careful not to initialise them in the stack
// array.
// The presence of chars >= ASIZE in the source string may adversely affect
// performance since we can only advance by one when we encounter one.
stp(zr, zr, pre(sp, -128));
for (int i = 1; i < 8; i++)
stp(zr, zr, Address(sp, i*16));
mov(cnt1tmp, 0);
sub(cnt1end, cnt1, 1);
BIND(BCLOOP);
ldrh(ch1, Address(str1, cnt1tmp, Address::lsl(1)));
cmp(ch1, 128);
add(cnt1tmp, cnt1tmp, 1);
br(HS, BCSKIP);
strb(cnt1tmp, Address(sp, ch1));
BIND(BCSKIP);
cmp(cnt1tmp, cnt1end);
br(LT, BCLOOP);
mov(result_tmp, str2);
sub(cnt2, cnt2, cnt1);
add(str2end, str2, cnt2, LSL, 1);
BIND(BMLOOPSTR2);
sub(cnt1tmp, cnt1, 1);
ldrh(ch1, Address(str1, cnt1tmp, Address::lsl(1)));
ldrh(skipch, Address(str2, cnt1tmp, Address::lsl(1)));
cmp(ch1, skipch);
br(NE, BMSKIP);
subs(cnt1tmp, cnt1tmp, 1);
br(LT, BMMATCH);
BIND(BMLOOPSTR1);
ldrh(ch1, Address(str1, cnt1tmp, Address::lsl(1)));
ldrh(ch2, Address(str2, cnt1tmp, Address::lsl(1)));
cmp(ch1, ch2);
br(NE, BMSKIP);
subs(cnt1tmp, cnt1tmp, 1);
br(GE, BMLOOPSTR1);
BIND(BMMATCH);
sub(result_tmp, str2, result_tmp);
lsr(result, result_tmp, 1);
add(sp, sp, 128);
b(DONE);
BIND(BMADV);
add(str2, str2, 2);
b(BMCHECKEND);
BIND(BMSKIP);
cmp(skipch, 128);
br(HS, BMADV);
ldrb(ch2, Address(sp, skipch));
add(str2, str2, cnt1, LSL, 1);
sub(str2, str2, ch2, LSL, 1);
BIND(BMCHECKEND);
cmp(str2, str2end);
br(LE, BMLOOPSTR2);
add(sp, sp, 128);
b(NOMATCH);
}
BIND(LINEARSEARCH);
{
Label DO1, DO2, DO3;
Register str2tmp = tmp2;
Register first = tmp3;
if (icnt1 == -1)
{
Label DOSHORT, FIRST_LOOP, STR2_NEXT, STR1_LOOP, STR1_NEXT, LAST_WORD;
cmp(cnt1, 4);
br(LT, DOSHORT);
sub(cnt2, cnt2, cnt1);
sub(cnt1, cnt1, 4);
mov(result_tmp, cnt2);
lea(str1, Address(str1, cnt1, Address::uxtw(1)));
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt1_neg, zr, cnt1, LSL, 1);
sub(cnt2_neg, zr, cnt2, LSL, 1);
ldr(first, Address(str1, cnt1_neg));
BIND(FIRST_LOOP);
ldr(ch2, Address(str2, cnt2_neg));
cmp(first, ch2);
br(EQ, STR1_LOOP);
BIND(STR2_NEXT);
adds(cnt2_neg, cnt2_neg, 2);
br(LE, FIRST_LOOP);
b(NOMATCH);
BIND(STR1_LOOP);
adds(cnt1tmp, cnt1_neg, 8);
add(cnt2tmp, cnt2_neg, 8);
br(GE, LAST_WORD);
BIND(STR1_NEXT);
ldr(ch1, Address(str1, cnt1tmp));
ldr(ch2, Address(str2, cnt2tmp));
cmp(ch1, ch2);
br(NE, STR2_NEXT);
adds(cnt1tmp, cnt1tmp, 8);
add(cnt2tmp, cnt2tmp, 8);
br(LT, STR1_NEXT);
BIND(LAST_WORD);
ldr(ch1, Address(str1));
sub(str2tmp, str2, cnt1_neg); // adjust to corresponding
ldr(ch2, Address(str2tmp, cnt2_neg)); // word in str2
cmp(ch1, ch2);
br(NE, STR2_NEXT);
b(MATCH);
BIND(DOSHORT);
cmp(cnt1, 2);
br(LT, DO1);
br(GT, DO3);
}
if (icnt1 == 4) {
Label CH1_LOOP;
ldr(ch1, str1);
sub(cnt2, cnt2, 4);
mov(result_tmp, cnt2);
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2_neg, zr, cnt2, LSL, 1);
BIND(CH1_LOOP);
ldr(ch2, Address(str2, cnt2_neg));
cmp(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, 2);
br(LE, CH1_LOOP);
b(NOMATCH);
}
if (icnt1 == -1 || icnt1 == 2) {
Label CH1_LOOP;
BIND(DO2);
ldrw(ch1, str1);
sub(cnt2, cnt2, 2);
mov(result_tmp, cnt2);
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2_neg, zr, cnt2, LSL, 1);
BIND(CH1_LOOP);
ldrw(ch2, Address(str2, cnt2_neg));
cmp(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, 2);
br(LE, CH1_LOOP);
b(NOMATCH);
}
if (icnt1 == -1 || icnt1 == 3) {
Label FIRST_LOOP, STR2_NEXT, STR1_LOOP;
BIND(DO3);
ldrw(first, str1);
ldrh(ch1, Address(str1, 4));
sub(cnt2, cnt2, 3);
mov(result_tmp, cnt2);
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2_neg, zr, cnt2, LSL, 1);
BIND(FIRST_LOOP);
ldrw(ch2, Address(str2, cnt2_neg));
cmpw(first, ch2);
br(EQ, STR1_LOOP);
BIND(STR2_NEXT);
adds(cnt2_neg, cnt2_neg, 2);
br(LE, FIRST_LOOP);
b(NOMATCH);
BIND(STR1_LOOP);
add(cnt2tmp, cnt2_neg, 4);
ldrh(ch2, Address(str2, cnt2tmp));
cmp(ch1, ch2);
br(NE, STR2_NEXT);
b(MATCH);
}
if (icnt1 == -1 || icnt1 == 1) {
Label CH1_LOOP, HAS_ZERO;
Label DO1_SHORT, DO1_LOOP;
BIND(DO1);
ldrh(ch1, str1);
cmp(cnt2, 4);
br(LT, DO1_SHORT);
orr(ch1, ch1, ch1, LSL, 16);
orr(ch1, ch1, ch1, LSL, 32);
sub(cnt2, cnt2, 4);
mov(result_tmp, cnt2);
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2_neg, zr, cnt2, LSL, 1);
mov(tmp3, 0x0001000100010001);
BIND(CH1_LOOP);
ldr(ch2, Address(str2, cnt2_neg));
eor(ch2, ch1, ch2);
sub(tmp1, ch2, tmp3);
orr(tmp2, ch2, 0x7fff7fff7fff7fff);
bics(tmp1, tmp1, tmp2);
br(NE, HAS_ZERO);
adds(cnt2_neg, cnt2_neg, 8);
br(LT, CH1_LOOP);
cmp(cnt2_neg, 8);
mov(cnt2_neg, 0);
br(LT, CH1_LOOP);
b(NOMATCH);
BIND(HAS_ZERO);
rev(tmp1, tmp1);
clz(tmp1, tmp1);
add(cnt2_neg, cnt2_neg, tmp1, LSR, 3);
b(MATCH);
BIND(DO1_SHORT);
mov(result_tmp, cnt2);
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2_neg, zr, cnt2, LSL, 1);
BIND(DO1_LOOP);
ldrh(ch2, Address(str2, cnt2_neg));
cmpw(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, 2);
br(LT, DO1_LOOP);
}
}
BIND(NOMATCH);
mov(result, -1);
b(DONE);
BIND(MATCH);
add(result, result_tmp, cnt2_neg, ASR, 1);
BIND(DONE);
}
// Compare strings.
void MacroAssembler::string_compare(Register str1, Register str2,
Register cnt1, Register cnt2, Register result,
Register tmp1) {
Label LENGTH_DIFF, DONE, SHORT_LOOP, SHORT_STRING,
NEXT_WORD, DIFFERENCE;
BLOCK_COMMENT("string_compare {");
// Compute the minimum of the string lengths and save the difference.
subsw(tmp1, cnt1, cnt2);
cselw(cnt2, cnt1, cnt2, Assembler::LE); // min
// A very short string
cmpw(cnt2, 4);
br(Assembler::LT, SHORT_STRING);
// Check if the strings start at the same location.
cmp(str1, str2);
br(Assembler::EQ, LENGTH_DIFF);
// Compare longwords
{
subw(cnt2, cnt2, 4); // The last longword is a special case
// Move both string pointers to the last longword of their
// strings, negate the remaining count, and convert it to bytes.
lea(str1, Address(str1, cnt2, Address::uxtw(1)));
lea(str2, Address(str2, cnt2, Address::uxtw(1)));
sub(cnt2, zr, cnt2, LSL, 1);
// Loop, loading longwords and comparing them into rscratch2.
bind(NEXT_WORD);
ldr(result, Address(str1, cnt2));
ldr(cnt1, Address(str2, cnt2));
adds(cnt2, cnt2, wordSize);
eor(rscratch2, result, cnt1);
cbnz(rscratch2, DIFFERENCE);
br(Assembler::LT, NEXT_WORD);
// Last longword. In the case where length == 4 we compare the
// same longword twice, but that's still faster than another
// conditional branch.
ldr(result, Address(str1));
ldr(cnt1, Address(str2));
eor(rscratch2, result, cnt1);
cbz(rscratch2, LENGTH_DIFF);
// Find the first different characters in the longwords and
// compute their difference.
bind(DIFFERENCE);
rev(rscratch2, rscratch2);
clz(rscratch2, rscratch2);
andr(rscratch2, rscratch2, -16);
lsrv(result, result, rscratch2);
uxthw(result, result);
lsrv(cnt1, cnt1, rscratch2);
uxthw(cnt1, cnt1);
subw(result, result, cnt1);
b(DONE);
}
bind(SHORT_STRING);
// Is the minimum length zero?
cbz(cnt2, LENGTH_DIFF);
bind(SHORT_LOOP);
load_unsigned_short(result, Address(post(str1, 2)));
load_unsigned_short(cnt1, Address(post(str2, 2)));
subw(result, result, cnt1);
cbnz(result, DONE);
sub(cnt2, cnt2, 1);
cbnz(cnt2, SHORT_LOOP);
// Strings are equal up to min length. Return the length difference.
bind(LENGTH_DIFF);
mov(result, tmp1);
// That's it
bind(DONE);
BLOCK_COMMENT("} string_compare");
}
// Compare Strings or char/byte arrays.
// is_string is true iff this is a string comparison.
// For Strings we're passed the address of the first characters in a1
// and a2 and the length in cnt1.
// For byte and char arrays we're passed the arrays themselves and we
// have to extract length fields and do null checks here.
// elem_size is the element size in bytes: either 1 or 2.
// There are two implementations. For arrays >= 8 bytes, all
// comparisons (including the final one, which may overlap) are
// performed 8 bytes at a time. For arrays < 8 bytes, we compare a
// halfword, then a short, and then a byte.
void MacroAssembler::arrays_equals(Register a1, Register a2,
Register result, Register cnt1,
int elem_size, bool is_string)
{
Label SAME, DONE, SHORT, NEXT_WORD, ONE;
Register tmp1 = rscratch1;
Register tmp2 = rscratch2;
Register cnt2 = tmp2; // cnt2 only used in array length compare
int elem_per_word = wordSize/elem_size;
int log_elem_size = exact_log2(elem_size);
int length_offset = arrayOopDesc::length_offset_in_bytes();
int base_offset
= arrayOopDesc::base_offset_in_bytes(elem_size == 2 ? T_CHAR : T_BYTE);
assert(elem_size == 1 || elem_size == 2, "must be char or byte");
assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
BLOCK_COMMENT(is_string ? "string_equals {" : "array_equals {");
mov(result, false);
if (!is_string) {
// if (a==a2)
// return true;
eor(rscratch1, a1, a2);
cbz(rscratch1, SAME);
// if (a==null || a2==null)
// return false;
cbz(a1, DONE);
cbz(a2, DONE);
// if (a1.length != a2.length)
// return false;
ldrw(cnt1, Address(a1, length_offset));
ldrw(cnt2, Address(a2, length_offset));
eorw(tmp1, cnt1, cnt2);
cbnzw(tmp1, DONE);
lea(a1, Address(a1, base_offset));
lea(a2, Address(a2, base_offset));
}
// Check for short strings, i.e. smaller than wordSize.
subs(cnt1, cnt1, elem_per_word);
br(Assembler::LT, SHORT);
// Main 8 byte comparison loop.
bind(NEXT_WORD); {
ldr(tmp1, Address(post(a1, wordSize)));
ldr(tmp2, Address(post(a2, wordSize)));
subs(cnt1, cnt1, elem_per_word);
eor(tmp1, tmp1, tmp2);
cbnz(tmp1, DONE);
} br(GT, NEXT_WORD);
// Last longword. In the case where length == 4 we compare the
// same longword twice, but that's still faster than another
// conditional branch.
// cnt1 could be 0, -1, -2, -3, -4 for chars; -4 only happens when
// length == 4.
if (log_elem_size > 0)
lsl(cnt1, cnt1, log_elem_size);
ldr(tmp1, Address(a1, cnt1));
ldr(tmp2, Address(a2, cnt1));
eor(tmp1, tmp1, tmp2);
cbnz(tmp1, DONE);
b(SAME);
bind(SHORT);
Label TAIL03, TAIL01;
tbz(cnt1, 2 - log_elem_size, TAIL03); // 0-7 bytes left.
{
ldrw(tmp1, Address(post(a1, 4)));
ldrw(tmp2, Address(post(a2, 4)));
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
bind(TAIL03);
tbz(cnt1, 1 - log_elem_size, TAIL01); // 0-3 bytes left.
{
ldrh(tmp1, Address(post(a1, 2)));
ldrh(tmp2, Address(post(a2, 2)));
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
bind(TAIL01);
if (elem_size == 1) { // Only needed when comparing byte arrays.
tbz(cnt1, 0, SAME); // 0-1 bytes left.
{
ldrb(tmp1, a1);
ldrb(tmp2, a2);
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
}
// Arrays are equal.
bind(SAME);
mov(result, true);
// That's it.
bind(DONE);
BLOCK_COMMENT(is_string ? "} string_equals" : "} array_equals");
}
// encode char[] to byte[] in ISO_8859_1
void MacroAssembler::encode_iso_array(Register src, Register dst,
Register len, Register result,
FloatRegister Vtmp1, FloatRegister Vtmp2,
FloatRegister Vtmp3, FloatRegister Vtmp4)
{
Label DONE, NEXT_32, LOOP_8, NEXT_8, LOOP_1, NEXT_1;
Register tmp1 = rscratch1;
mov(result, len); // Save initial len
#ifndef BUILTIN_SIM
subs(len, len, 32);
br(LT, LOOP_8);
// The following code uses the SIMD 'uqxtn' and 'uqxtn2' instructions
// to convert chars to bytes. These set the 'QC' bit in the FPSR if
// any char could not fit in a byte, so clear the FPSR so we can test it.
clear_fpsr();
BIND(NEXT_32);
ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
uqxtn(Vtmp1, T8B, Vtmp1, T8H); // uqxtn - write bottom half
uqxtn(Vtmp1, T16B, Vtmp2, T8H); // uqxtn2 - write top half
uqxtn(Vtmp2, T8B, Vtmp3, T8H);
uqxtn(Vtmp2, T16B, Vtmp4, T8H); // uqxtn2
get_fpsr(tmp1);
cbnzw(tmp1, LOOP_8);
st1(Vtmp1, Vtmp2, T16B, post(dst, 32));
subs(len, len, 32);
add(src, src, 64);
br(GE, NEXT_32);
BIND(LOOP_8);
adds(len, len, 32-8);
br(LT, LOOP_1);
clear_fpsr(); // QC may be set from loop above, clear again
BIND(NEXT_8);
ld1(Vtmp1, T8H, src);
uqxtn(Vtmp1, T8B, Vtmp1, T8H);
get_fpsr(tmp1);
cbnzw(tmp1, LOOP_1);
st1(Vtmp1, T8B, post(dst, 8));
subs(len, len, 8);
add(src, src, 16);
br(GE, NEXT_8);
BIND(LOOP_1);
adds(len, len, 8);
br(LE, DONE);
#else
cbz(len, DONE);
#endif
BIND(NEXT_1);
ldrh(tmp1, Address(post(src, 2)));
tst(tmp1, 0xff00);
br(NE, DONE);
strb(tmp1, Address(post(dst, 1)));
subs(len, len, 1);
br(GT, NEXT_1);
BIND(DONE);
sub(result, result, len); // Return index where we stopped
}
// get_thread() can be called anywhere inside generated code so we
// need to save whatever non-callee save context might get clobbered
// by the call to JavaThread::aarch64_get_thread_helper() or, indeed,
// the call setup code.
//
// aarch64_get_thread_helper() clobbers only r0, r1, and flags.
//
void MacroAssembler::get_thread(Register dst) {
RegSet saved_regs = RegSet::range(r0, r1) + lr - dst;
push(saved_regs, sp);
mov(lr, CAST_FROM_FN_PTR(address, JavaThread::aarch64_get_thread_helper));
blrt(lr, 1, 0, 1);
if (dst != c_rarg0) {
mov(dst, c_rarg0);
}
pop(saved_regs, sp);
}