8230565: ZGC: Redesign C2 load barrier to expand on the MachNode level
Reviewed-by: pliden, stefank, neliasso
Contributed-by: erik.osterlund@oracle.com, per.liden@oracle.com, stefan.karlsson@oracle.com, nils.eliasson@oracle.com
/*
* Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2014, 2019, 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 "jvm.h"
#include "asm/assembler.hpp"
#include "asm/assembler.inline.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/cardTable.hpp"
#include "gc/shared/barrierSetAssembler.hpp"
#include "gc/shared/cardTableBarrierSet.hpp"
#include "interpreter/interpreter.hpp"
#include "compiler/disassembler.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "nativeInst_aarch64.hpp"
#include "oops/accessDecorators.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/klass.inline.hpp"
#include "runtime/biasedLocking.hpp"
#include "runtime/icache.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/jniHandles.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/thread.hpp"
#ifdef COMPILER1
#include "c1/c1_LIRAssembler.hpp"
#endif
#ifdef COMPILER2
#include "oops/oop.hpp"
#include "opto/compile.hpp"
#include "opto/intrinsicnode.hpp"
#include "opto/node.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 = CompressedOops::encode((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;
}
int MacroAssembler::patch_narrow_klass(address insn_addr, narrowKlass n) {
// Metatdata pointers are either narrow (32 bits) or wide (48 bits).
// We encode narrow ones by setting the upper 16 bits in the first
// instruction.
NativeInstruction *insn = nativeInstruction_at(insn_addr);
assert(Instruction_aarch64::extract(insn->encoding(), 31, 21) == 0b11010010101 &&
nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
return 2 * 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::safepoint_poll(Label& slow_path) {
if (SafepointMechanism::uses_thread_local_poll()) {
ldr(rscratch1, Address(rthread, Thread::polling_page_offset()));
tbnz(rscratch1, exact_log2(SafepointMechanism::poll_bit()), slow_path);
} else {
unsigned long offset;
adrp(rscratch1, ExternalAddress(SafepointSynchronize::address_of_state()), offset);
ldrw(rscratch1, Address(rscratch1, offset));
assert(SafepointSynchronize::_not_synchronized == 0, "rewrite this code");
cbnz(rscratch1, slow_path);
}
}
// Just like safepoint_poll, but use an acquiring load for thread-
// local polling.
//
// We need an acquire here to ensure that any subsequent load of the
// global SafepointSynchronize::_state flag is ordered after this load
// of the local Thread::_polling page. We don't want this poll to
// return false (i.e. not safepointing) and a later poll of the global
// SafepointSynchronize::_state spuriously to return true.
//
// This is to avoid a race when we're in a native->Java transition
// racing the code which wakes up from a safepoint.
//
void MacroAssembler::safepoint_poll_acquire(Label& slow_path) {
if (SafepointMechanism::uses_thread_local_poll()) {
lea(rscratch1, Address(rthread, Thread::polling_page_offset()));
ldar(rscratch1, rscratch1);
tbnz(rscratch1, exact_log2(SafepointMechanism::poll_bit()), slow_path);
} else {
safepoint_poll(slow_path);
}
}
void MacroAssembler::reset_last_Java_frame(bool clear_fp) {
// 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()));
}
// Always clear the pc because it could have been set by make_walkable()
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) {
assert(last_java_pc != NULL, "must provide a valid PC");
adr(scratch, last_java_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, pc() /* Patched later */, 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);
}
}
void MacroAssembler::reserved_stack_check() {
// testing if reserved zone needs to be enabled
Label no_reserved_zone_enabling;
ldr(rscratch1, Address(rthread, JavaThread::reserved_stack_activation_offset()));
cmp(sp, rscratch1);
br(Assembler::LO, no_reserved_zone_enabling);
enter(); // LR and FP are live.
lea(rscratch1, CAST_FROM_FN_PTR(address, SharedRuntime::enable_stack_reserved_zone));
mov(c_rarg0, rthread);
blr(rscratch1);
leave();
// We have already removed our own frame.
// throw_delayed_StackOverflowError will think that it's been
// called by our caller.
lea(rscratch1, RuntimeAddress(StubRoutines::throw_delayed_StackOverflowError_entry()));
br(rscratch1);
should_not_reach_here();
bind(no_reserved_zone_enabling);
}
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(markWord::age_shift == markWord::lock_bits + markWord::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, markWord::biased_lock_mask_in_place);
cmp(tmp_reg, (u1)markWord::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) markWord::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, markWord::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, markWord::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, markWord::biased_lock_mask_in_place | markWord::age_mask_in_place | markWord::epoch_mask_in_place);
andr(swap_reg, swap_reg, rscratch1);
orr(tmp_reg, swap_reg, rthread);
cmpxchg_obj_header(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);
cmpxchg_obj_header(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);
cmpxchg_obj_header(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, markWord::biased_lock_mask_in_place);
cmp(temp_reg, (u1)markWord::biased_lock_pattern);
br(Assembler::EQ, done);
}
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);
// 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(JavaThread::current()->is_Compiler_thread(), "just checking");
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");
// We need a trampoline if branches are far.
if (far_branches()) {
bool in_scratch_emit_size = false;
#ifdef COMPILER2
// We don't want to emit a trampoline if C2 is generating dummy
// code during its branch shortening phase.
CompileTask* task = ciEnv::current()->task();
in_scratch_emit_size =
(task != NULL && is_c2_compile(task->comp_level()) &&
Compile::current()->in_scratch_emit_size());
#endif
if (!in_scratch_emit_size) {
address stub = emit_trampoline_stub(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) {
// Max stub size: alignment nop, TrampolineStub.
address stub = start_a_stub(NativeInstruction::instruction_size
+ NativeCallTrampolineStub::instruction_size);
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_start_addr;
}
void MacroAssembler::emit_static_call_stub() {
// CompiledDirectStaticCall::set_to_interpreted knows the
// exact layout of this stub.
isb();
mov_metadata(rmethod, (Metadata*)NULL);
// Jump to the entry point of the i2c stub.
movptr(rscratch1, 0);
br(rscratch1);
}
void MacroAssembler::c2bool(Register x) {
// implements x == 0 ? 0 : 1
// note: must only look at least-significant byte of x
// since C-style booleans are stored in one byte
// only! (was bug)
tst(x, 0xff);
cset(x, Assembler::NE);
}
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);
}
// 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,
bool return_method) {
assert_different_registers(recv_klass, intf_klass, scan_temp);
assert_different_registers(method_result, intf_klass, scan_temp);
assert(recv_klass != method_result || !return_method,
"recv_klass can be destroyed when method isn't needed");
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);
if (return_method) {
// 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.
if (return_method) {
ldrw(scan_temp, Address(scan_temp, itableOffsetEntry::offset_offset_in_bytes()));
ldr(method_result, Address(recv_klass, scan_temp, Address::uxtw(0)));
}
}
// 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,
form_address(rscratch1, recv_klass, vtable_offset_in_bytes, 0));
}
}
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);
subs(zr, 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)
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);
// Get super_klass value into r0 (even if it was in r5 or r2).
if (super_klass != r0) {
mov(r0, super_klass);
}
#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::clinit_barrier(Register klass, Register scratch, Label* L_fast_path, Label* L_slow_path) {
assert(L_fast_path != NULL || L_slow_path != NULL, "at least one is required");
assert_different_registers(klass, rthread, scratch);
Label L_fallthrough, L_tmp;
if (L_fast_path == NULL) {
L_fast_path = &L_fallthrough;
} else if (L_slow_path == NULL) {
L_slow_path = &L_fallthrough;
}
// Fast path check: class is fully initialized
ldrb(scratch, Address(klass, InstanceKlass::init_state_offset()));
subs(zr, scratch, InstanceKlass::fully_initialized);
br(Assembler::EQ, *L_fast_path);
// Fast path check: current thread is initializer thread
ldr(scratch, Address(klass, InstanceKlass::init_thread_offset()));
cmp(rthread, scratch);
if (L_slow_path == &L_fallthrough) {
br(Assembler::EQ, *L_fast_path);
bind(*L_slow_path);
} else if (L_fast_path == &L_fallthrough) {
br(Assembler::NE, *L_slow_path);
bind(*L_fast_path);
} else {
Unimplemented();
}
}
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) {
Label E, L;
stp(rscratch1, rmethod, Address(pre(sp, -2 * wordSize)));
mov(rscratch1, entry_point);
blr(rscratch1);
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) {
if (UseLSE) {
mov(tmp, 1);
ldadd(Assembler::word, tmp, zr, counter_addr);
return;
}
Label retry_load;
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
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;
address last = code()->last_insn();
if (last != NULL && nativeInstruction_at(last)->is_Membar() && prev == last) {
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_insn(pc());
dmb(Assembler::barrier(order_constraint));
}
}
bool MacroAssembler::try_merge_ldst(Register rt, const Address &adr, size_t size_in_bytes, bool is_store) {
if (ldst_can_merge(rt, adr, size_in_bytes, is_store)) {
merge_ldst(rt, adr, size_in_bytes, is_store);
code()->clear_last_insn();
return true;
} else {
assert(size_in_bytes == 8 || size_in_bytes == 4, "only 8 bytes or 4 bytes load/store is supported.");
const unsigned mask = size_in_bytes - 1;
if (adr.getMode() == Address::base_plus_offset &&
(adr.offset() & mask) == 0) { // only supports base_plus_offset.
code()->set_last_insn(pc());
}
return false;
}
}
void MacroAssembler::ldr(Register Rx, const Address &adr) {
// We always try to merge two adjacent loads into one ldp.
if (!try_merge_ldst(Rx, adr, 8, false)) {
Assembler::ldr(Rx, adr);
}
}
void MacroAssembler::ldrw(Register Rw, const Address &adr) {
// We always try to merge two adjacent loads into one ldp.
if (!try_merge_ldst(Rw, adr, 4, false)) {
Assembler::ldrw(Rw, adr);
}
}
void MacroAssembler::str(Register Rx, const Address &adr) {
// We always try to merge two adjacent stores into one stp.
if (!try_merge_ldst(Rx, adr, 8, true)) {
Assembler::str(Rx, adr);
}
}
void MacroAssembler::strw(Register Rw, const Address &adr) {
// We always try to merge two adjacent stores into one stp.
if (!try_merge_ldst(Rw, adr, 4, true)) {
Assembler::strw(Rw, adr);
}
}
// 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");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
ldrw(rscratch1, dst);
decrementw(rscratch1, value);
strw(rscratch1, dst);
}
void MacroAssembler::decrement(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid address for decrement");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
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");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
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");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
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;
}
// Push lots of registers in the bit set supplied. Don't push sp.
// Return the number of words pushed
int MacroAssembler::push_fp(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 <= 31; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->encoding_nocheck();
count &= ~1; // Only push an even number of regs
// Always pushing full 128 bit registers.
if (count) {
stpq(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(pre(stack, -count * wordSize * 2)));
words_pushed += 2;
}
for (int i = 2; i < count; i += 2) {
stpq(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize * 2));
words_pushed += 2;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
int MacroAssembler::pop_fp(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 <= 31; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->encoding_nocheck();
count &= ~1;
for (int i = 2; i < count; i += 2) {
ldpq(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize * 2));
words_pushed += 2;
}
if (count) {
ldpq(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(post(stack, count * wordSize * 2)));
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)CompressedOops::ptrs_base_addr()));
br(Assembler::EQ, ok);
stop(msg);
bind(ok);
pop(1 << rscratch1->encoding(), sp);
}
#endif
}
#endif
void MacroAssembler::resolve_jobject(Register value, Register thread, Register tmp) {
Label done, not_weak;
cbz(value, done); // Use NULL as-is.
STATIC_ASSERT(JNIHandles::weak_tag_mask == 1u);
tbz(r0, 0, not_weak); // Test for jweak tag.
// Resolve jweak.
access_load_at(T_OBJECT, IN_NATIVE | ON_PHANTOM_OOP_REF, value,
Address(value, -JNIHandles::weak_tag_value), tmp, thread);
verify_oop(value);
b(done);
bind(not_weak);
// Resolve (untagged) jobject.
access_load_at(T_OBJECT, IN_NATIVE, value, Address(value, 0), tmp, thread);
verify_oop(value);
bind(done);
}
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));
blr(c_rarg3);
hlt(0);
}
void MacroAssembler::warn(const char* msg) {
pusha();
mov(c_rarg0, (address)msg);
mov(lr, CAST_FROM_FN_PTR(address, warning));
blr(lr);
popa();
}
void MacroAssembler::unimplemented(const char* what) {
const char* buf = NULL;
{
ResourceMark rm;
stringStream ss;
ss.print("unimplemented: %s", what);
buf = code_string(ss.as_string());
}
stop(buf);
}
// 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, CompressedOops::ptrs_base());
} else {
lea(rheapbase, ExternalAddress((address)CompressedOops::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;
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
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::cmpxchg_obj_header(Register oldv, Register newv, Register obj, Register tmp,
Label &succeed, Label *fail) {
assert(oopDesc::mark_offset_in_bytes() == 0, "assumption");
cmpxchgptr(oldv, newv, obj, tmp, succeed, 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;
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
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. A weak CAS
// doesn't retry and may fail spuriously. If the oldval is wanted,
// Pass a register for the result, otherwise pass noreg.
// Clobbers rscratch1
void MacroAssembler::cmpxchg(Register addr, Register expected,
Register new_val,
enum operand_size size,
bool acquire, bool release,
bool weak,
Register result) {
if (result == noreg) result = rscratch1;
BLOCK_COMMENT("cmpxchg {");
if (UseLSE) {
mov(result, expected);
lse_cas(result, new_val, addr, size, acquire, release, /*not_pair*/ true);
compare_eq(result, expected, size);
} else {
Label retry_load, done;
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
load_exclusive(result, addr, size, acquire);
compare_eq(result, expected, size);
br(Assembler::NE, done);
store_exclusive(rscratch1, new_val, addr, size, release);
if (weak) {
cmpw(rscratch1, 0u); // If the store fails, return NE to our caller.
} else {
cbnzw(rscratch1, retry_load);
}
bind(done);
}
BLOCK_COMMENT("} cmpxchg");
}
// A generic comparison. Only compares for equality, clobbers rscratch1.
void MacroAssembler::compare_eq(Register rm, Register rn, enum operand_size size) {
if (size == xword) {
cmp(rm, rn);
} else if (size == word) {
cmpw(rm, rn);
} else if (size == halfword) {
eorw(rscratch1, rm, rn);
ands(zr, rscratch1, 0xffff);
} else if (size == byte) {
eorw(rscratch1, rm, rn);
ands(zr, rscratch1, 0xff);
} else {
ShouldNotReachHere();
}
}
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(NAME, LDXR, OP, IOP, AOP, STXR, sz) \
void MacroAssembler::atomic_##NAME(Register prev, RegisterOrConstant incr, Register addr) { \
if (UseLSE) { \
prev = prev->is_valid() ? prev : zr; \
if (incr.is_register()) { \
AOP(sz, incr.as_register(), prev, addr); \
} else { \
mov(rscratch2, incr.as_constant()); \
AOP(sz, rscratch2, prev, addr); \
} \
return; \
} \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, incr, addr) ? prev : rscratch2; \
\
Label retry_load; \
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH)) \
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(add, ldxr, add, sub, ldadd, stxr, Assembler::xword)
ATOMIC_OP(addw, ldxrw, addw, subw, ldadd, stxrw, Assembler::word)
ATOMIC_OP(addal, ldaxr, add, sub, ldaddal, stlxr, Assembler::xword)
ATOMIC_OP(addalw, ldaxrw, addw, subw, ldaddal, stlxrw, Assembler::word)
#undef ATOMIC_OP
#define ATOMIC_XCHG(OP, AOP, LDXR, STXR, sz) \
void MacroAssembler::atomic_##OP(Register prev, Register newv, Register addr) { \
if (UseLSE) { \
prev = prev->is_valid() ? prev : zr; \
AOP(sz, newv, prev, addr); \
return; \
} \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, newv, addr) ? prev : rscratch2; \
\
Label retry_load; \
if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH)) \
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, swp, ldxr, stxr, Assembler::xword)
ATOMIC_XCHG(xchgw, swp, ldxrw, stxrw, Assembler::word)
ATOMIC_XCHG(xchgal, swpal, ldaxr, stlxr, Assembler::xword)
ATOMIC_XCHG(xchgalw, swpal, ldaxrw, stlxrw, Assembler::word)
#undef ATOMIC_XCHG
#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;
}
}
fatal("DEBUG MESSAGE: %s", msg);
}
void MacroAssembler::push_call_clobbered_registers() {
int step = 4 * wordSize;
push(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
sub(sp, sp, step);
mov(rscratch1, -step);
// Push v0-v7, v16-v31.
for (int i = 31; i>= 4; i -= 4) {
if (i <= v7->encoding() || i >= v16->encoding())
st1(as_FloatRegister(i-3), as_FloatRegister(i-2), as_FloatRegister(i-1),
as_FloatRegister(i), T1D, Address(post(sp, rscratch1)));
}
st1(as_FloatRegister(0), as_FloatRegister(1), as_FloatRegister(2),
as_FloatRegister(3), T1D, Address(sp));
}
void MacroAssembler::pop_call_clobbered_registers() {
for (int i = 0; i < 32; i += 4) {
if (i <= v7->encoding() || i >= v16->encoding())
ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), T1D, Address(post(sp, 4 * wordSize)));
}
pop(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
}
void MacroAssembler::push_CPU_state(bool save_vectors) {
int step = (save_vectors ? 8 : 4) * wordSize;
push(0x3fffffff, sp); // integer registers except lr & sp
mov(rscratch1, -step);
sub(sp, sp, step);
for (int i = 28; i >= 4; i -= 4) {
st1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), save_vectors ? T2D : T1D, Address(post(sp, rscratch1)));
}
st1(v0, v1, v2, v3, save_vectors ? T2D : T1D, sp);
}
void MacroAssembler::pop_CPU_state(bool restore_vectors) {
int step = (restore_vectors ? 8 : 4) * wordSize;
for (int i = 0; i <= 28; i += 4)
ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), restore_vectors ? T2D : T1D, Address(post(sp, step)));
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 &= -1u<<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);
}
// Checks whether offset is aligned.
// Returns true if it is, else false.
bool MacroAssembler::merge_alignment_check(Register base,
size_t size,
long cur_offset,
long prev_offset) const {
if (AvoidUnalignedAccesses) {
if (base == sp) {
// Checks whether low offset if aligned to pair of registers.
long pair_mask = size * 2 - 1;
long offset = prev_offset > cur_offset ? cur_offset : prev_offset;
return (offset & pair_mask) == 0;
} else { // If base is not sp, we can't guarantee the access is aligned.
return false;
}
} else {
long mask = size - 1;
// Load/store pair instruction only supports element size aligned offset.
return (cur_offset & mask) == 0 && (prev_offset & mask) == 0;
}
}
// Checks whether current and previous loads/stores can be merged.
// Returns true if it can be merged, else false.
bool MacroAssembler::ldst_can_merge(Register rt,
const Address &adr,
size_t cur_size_in_bytes,
bool is_store) const {
address prev = pc() - NativeInstruction::instruction_size;
address last = code()->last_insn();
if (last == NULL || !nativeInstruction_at(last)->is_Imm_LdSt()) {
return false;
}
if (adr.getMode() != Address::base_plus_offset || prev != last) {
return false;
}
NativeLdSt* prev_ldst = NativeLdSt_at(prev);
size_t prev_size_in_bytes = prev_ldst->size_in_bytes();
assert(prev_size_in_bytes == 4 || prev_size_in_bytes == 8, "only supports 64/32bit merging.");
assert(cur_size_in_bytes == 4 || cur_size_in_bytes == 8, "only supports 64/32bit merging.");
if (cur_size_in_bytes != prev_size_in_bytes || is_store != prev_ldst->is_store()) {
return false;
}
long max_offset = 63 * prev_size_in_bytes;
long min_offset = -64 * prev_size_in_bytes;
assert(prev_ldst->is_not_pre_post_index(), "pre-index or post-index is not supported to be merged.");
// Only same base can be merged.
if (adr.base() != prev_ldst->base()) {
return false;
}
long cur_offset = adr.offset();
long prev_offset = prev_ldst->offset();
size_t diff = abs(cur_offset - prev_offset);
if (diff != prev_size_in_bytes) {
return false;
}
// Following cases can not be merged:
// ldr x2, [x2, #8]
// ldr x3, [x2, #16]
// or:
// ldr x2, [x3, #8]
// ldr x2, [x3, #16]
// If t1 and t2 is the same in "ldp t1, t2, [xn, #imm]", we'll get SIGILL.
if (!is_store && (adr.base() == prev_ldst->target() || rt == prev_ldst->target())) {
return false;
}
long low_offset = prev_offset > cur_offset ? cur_offset : prev_offset;
// Offset range must be in ldp/stp instruction's range.
if (low_offset > max_offset || low_offset < min_offset) {
return false;
}
if (merge_alignment_check(adr.base(), prev_size_in_bytes, cur_offset, prev_offset)) {
return true;
}
return false;
}
// Merge current load/store with previous load/store into ldp/stp.
void MacroAssembler::merge_ldst(Register rt,
const Address &adr,
size_t cur_size_in_bytes,
bool is_store) {
assert(ldst_can_merge(rt, adr, cur_size_in_bytes, is_store) == true, "cur and prev must be able to be merged.");
Register rt_low, rt_high;
address prev = pc() - NativeInstruction::instruction_size;
NativeLdSt* prev_ldst = NativeLdSt_at(prev);
long offset;
if (adr.offset() < prev_ldst->offset()) {
offset = adr.offset();
rt_low = rt;
rt_high = prev_ldst->target();
} else {
offset = prev_ldst->offset();
rt_low = prev_ldst->target();
rt_high = rt;
}
Address adr_p = Address(prev_ldst->base(), offset);
// Overwrite previous generated binary.
code_section()->set_end(prev);
const int sz = prev_ldst->size_in_bytes();
assert(sz == 8 || sz == 4, "only supports 64/32bit merging.");
if (!is_store) {
BLOCK_COMMENT("merged ldr pair");
if (sz == 8) {
ldp(rt_low, rt_high, adr_p);
} else {
ldpw(rt_low, rt_high, adr_p);
}
} else {
BLOCK_COMMENT("merged str pair");
if (sz == 8) {
stp(rt_low, rt_high, adr_p);
} else {
stpw(rt_low, rt_high, adr_p);
}
}
}
/**
* 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);
}
// Code for BigInteger::mulAdd instrinsic
// out = r0
// in = r1
// offset = r2 (already out.length-offset)
// len = r3
// k = r4
//
// pseudo code from java implementation:
// carry = 0;
// offset = out.length-offset - 1;
// for (int j=len-1; j >= 0; j--) {
// product = (in[j] & LONG_MASK) * kLong + (out[offset] & LONG_MASK) + carry;
// out[offset--] = (int)product;
// carry = product >>> 32;
// }
// return (int)carry;
void MacroAssembler::mul_add(Register out, Register in, Register offset,
Register len, Register k) {
Label LOOP, END;
// pre-loop
cmp(len, zr); // cmp, not cbz/cbnz: to use condition twice => less branches
csel(out, zr, out, Assembler::EQ);
br(Assembler::EQ, END);
add(in, in, len, LSL, 2); // in[j+1] address
add(offset, out, offset, LSL, 2); // out[offset + 1] address
mov(out, zr); // used to keep carry now
BIND(LOOP);
ldrw(rscratch1, Address(pre(in, -4)));
madd(rscratch1, rscratch1, k, out);
ldrw(rscratch2, Address(pre(offset, -4)));
add(rscratch1, rscratch1, rscratch2);
strw(rscratch1, Address(offset));
lsr(out, rscratch1, 32);
subs(len, len, 1);
br(Assembler::NE, LOOP);
BIND(END);
}
/**
* 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);
}
void MacroAssembler::kernel_crc32_using_crc32(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2,
Register tmp3) {
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
mvnw(crc, crc);
subs(len, len, 128);
br(Assembler::GE, CRC_by64_pre);
BIND(CRC_less64);
adds(len, len, 128-32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(post(buf, 16)));
subs(len, len, 32);
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(post(buf, 8)));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(post(buf, 8)));
crc32x(crc, crc, tmp2);
crc32x(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, 32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32w(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32b(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by64_pre);
sub(buf, buf, 8);
ldp(tmp0, tmp1, Address(buf, 8));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
b(CRC_by64_loop);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 8));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 16));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
br(Assembler::GE, CRC_by64_loop);
// post-loop
crc32x(crc, crc, tmp2);
crc32x(crc, crc, tmp3);
sub(len, len, 64);
add(buf, buf, 8);
cmn(len, 128);
br(Assembler::NE, CRC_less64);
BIND(L_exit);
mvnw(crc, 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_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;
if (UseCRC32) {
kernel_crc32_using_crc32(crc, buf, len, table0, table1, table2, table3);
return;
}
mvnw(crc, crc);
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, (u1)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, T8H, v20, v22);
uzp2(v25, T8H, v20, v22);
eor(v20, T16B, v24, v25);
uzp1(v26, T8H, v16, v18);
uzp2(v27, T8H, v16, v18);
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, T2D, v16, v20);
uzp2(v21, T2D, v16, v20);
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, T2D, v20, v16);
uzp2(v21, T2D, v20, v16);
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, T8H, v20, v22);
uzp2(v25, T8H, v20, v22);
eor(v20, T16B, v24, v25);
uzp1(v26, T8H, v16, v18);
uzp2(v27, T8H, v16, v18);
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, T2D, v16, v20);
uzp2(v21, T2D, v16, v20);
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, T2D, v20, v16);
uzp2(v21, T2D, v20, v16);
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);
mvnw(crc, crc);
}
void MacroAssembler::kernel_crc32c_using_crc32c(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2,
Register tmp3) {
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
subs(len, len, 128);
br(Assembler::GE, CRC_by64_pre);
BIND(CRC_less64);
adds(len, len, 128-32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(post(buf, 16)));
subs(len, len, 32);
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(post(buf, 8)));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(post(buf, 8)));
crc32cx(crc, crc, tmp2);
crc32cx(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, 32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32cw(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32cb(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by64_pre);
sub(buf, buf, 8);
ldp(tmp0, tmp1, Address(buf, 8));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
b(CRC_by64_loop);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 8));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 16));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
br(Assembler::GE, CRC_by64_loop);
// post-loop
crc32cx(crc, crc, tmp2);
crc32cx(crc, crc, tmp3);
sub(len, len, 64);
add(buf, buf, 8);
cmn(len, 128);
br(Assembler::NE, CRC_less64);
BIND(L_exit);
}
/**
* @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) {
kernel_crc32c_using_crc32c(crc, buf, len, table0, table1, table2, table3);
}
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::cmpoop(Register obj1, Register obj2) {
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
bs->obj_equals(this, obj1, obj2);
}
void MacroAssembler::load_method_holder(Register holder, Register method) {
ldr(holder, Address(method, Method::const_offset())); // ConstMethod*
ldr(holder, Address(holder, ConstMethod::constants_offset())); // ConstantPool*
ldr(holder, Address(holder, ConstantPool::pool_holder_offset_in_bytes())); // InstanceKlass*
}
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()));
}
}
// ((OopHandle)result).resolve();
void MacroAssembler::resolve_oop_handle(Register result, Register tmp) {
// OopHandle::resolve is an indirection.
access_load_at(T_OBJECT, IN_NATIVE, result, Address(result, 0), tmp, noreg);
}
void MacroAssembler::load_mirror(Register dst, Register method, Register tmp) {
const int mirror_offset = in_bytes(Klass::java_mirror_offset());
ldr(dst, Address(rmethod, Method::const_offset()));
ldr(dst, Address(dst, ConstMethod::constants_offset()));
ldr(dst, Address(dst, ConstantPool::pool_holder_offset_in_bytes()));
ldr(dst, Address(dst, mirror_offset));
resolve_oop_handle(dst, tmp);
}
void MacroAssembler::cmp_klass(Register oop, Register trial_klass, Register tmp) {
if (UseCompressedClassPointers) {
ldrw(tmp, Address(oop, oopDesc::klass_offset_in_bytes()));
if (CompressedKlassPointers::base() == NULL) {
cmp(trial_klass, tmp, LSL, CompressedKlassPointers::shift());
return;
} else if (((uint64_t)CompressedKlassPointers::base() & 0xffffffff) == 0
&& CompressedKlassPointers::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 CompressedOops::encode.
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 (CompressedOops::base() == NULL) {
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::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 (CompressedOops::base() != NULL) {
sub(r, r, rheapbase);
}
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::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 (CompressedOops::base() != NULL) {
sub(dst, src, rheapbase);
data = dst;
}
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::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 (CompressedOops::base() == NULL) {
if (CompressedOops::shift() != 0 || d != s) {
lsl(d, s, CompressedOops::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 (CompressedOops::shift() != 0) {
assert(LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
if (CompressedOops::base() != NULL) {
add(r, rheapbase, r, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(r, zr, r, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (CompressedOops::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 (CompressedOops::shift() != 0) {
assert(LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
if (CompressedOops::base() != NULL) {
add(dst, rheapbase, src, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(dst, zr, src, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (CompressedOops::base() == NULL, "sanity");
if (dst != src) {
mov(dst, src);
}
}
}
void MacroAssembler::encode_klass_not_null(Register dst, Register src) {
if (CompressedKlassPointers::base() == NULL) {
if (CompressedKlassPointers::shift() != 0) {
assert (LogKlassAlignmentInBytes == CompressedKlassPointers::shift(), "decode alg wrong");
lsr(dst, src, LogKlassAlignmentInBytes);
} else {
if (dst != src) mov(dst, src);
}
return;
}
if (use_XOR_for_compressed_class_base) {
if (CompressedKlassPointers::shift() != 0) {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
lsr(dst, dst, LogKlassAlignmentInBytes);
} else {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
}
return;
}
if (((uint64_t)CompressedKlassPointers::base() & 0xffffffff) == 0
&& CompressedKlassPointers::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)CompressedKlassPointers::base());
sub(dst, src, rbase);
if (CompressedKlassPointers::shift() != 0) {
assert (LogKlassAlignmentInBytes == CompressedKlassPointers::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 (CompressedKlassPointers::base() == NULL) {
if (CompressedKlassPointers::shift() != 0) {
assert(LogKlassAlignmentInBytes == CompressedKlassPointers::shift(), "decode alg wrong");
lsl(dst, src, LogKlassAlignmentInBytes);
} else {
if (dst != src) mov(dst, src);
}
return;
}
if (use_XOR_for_compressed_class_base) {
if (CompressedKlassPointers::shift() != 0) {
lsl(dst, src, LogKlassAlignmentInBytes);
eor(dst, dst, (uint64_t)CompressedKlassPointers::base());
} else {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
}
return;
}
if (((uint64_t)CompressedKlassPointers::base() & 0xffffffff) == 0
&& CompressedKlassPointers::shift() == 0) {
if (dst != src)
movw(dst, src);
movk(dst, (uint64_t)CompressedKlassPointers::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)CompressedKlassPointers::base());
if (CompressedKlassPointers::shift() != 0) {
assert(LogKlassAlignmentInBytes == CompressedKlassPointers::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) {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
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");
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "should be real oop");
}
#endif
int oop_index = oop_recorder()->find_index(obj);
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(k), "should not be an oop");
InstructionMark im(this);
RelocationHolder rspec = metadata_Relocation::spec(index);
code_section()->relocate(inst_mark(), rspec);
narrowKlass nk = CompressedKlassPointers::encode(k);
movz(dst, (nk >> 16), 16);
movk(dst, nk & 0xffff);
}
void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators,
Register dst, Address src,
Register tmp1, Register thread_tmp) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::load_at(this, decorators, type, dst, src, tmp1, thread_tmp);
} else {
bs->load_at(this, decorators, type, dst, src, tmp1, thread_tmp);
}
}
void MacroAssembler::access_store_at(BasicType type, DecoratorSet decorators,
Address dst, Register src,
Register tmp1, Register thread_tmp) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::store_at(this, decorators, type, dst, src, tmp1, thread_tmp);
} else {
bs->store_at(this, decorators, type, dst, src, tmp1, thread_tmp);
}
}
void MacroAssembler::resolve(DecoratorSet decorators, Register obj) {
// Use stronger ACCESS_WRITE|ACCESS_READ by default.
if ((decorators & (ACCESS_READ | ACCESS_WRITE)) == 0) {
decorators |= ACCESS_READ | ACCESS_WRITE;
}
BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
return bs->resolve(this, decorators, obj);
}
void MacroAssembler::load_heap_oop(Register dst, Address src, Register tmp1,
Register thread_tmp, DecoratorSet decorators) {
access_load_at(T_OBJECT, IN_HEAP | decorators, dst, src, tmp1, thread_tmp);
}
void MacroAssembler::load_heap_oop_not_null(Register dst, Address src, Register tmp1,
Register thread_tmp, DecoratorSet decorators) {
access_load_at(T_OBJECT, IN_HEAP | IS_NOT_NULL | decorators, dst, src, tmp1, thread_tmp);
}
void MacroAssembler::store_heap_oop(Address dst, Register src, Register tmp1,
Register thread_tmp, DecoratorSet decorators) {
access_store_at(T_OBJECT, IN_HEAP | decorators, dst, src, tmp1, thread_tmp);
}
// Used for storing NULLs.
void MacroAssembler::store_heap_oop_null(Address dst) {
access_store_at(T_OBJECT, IN_HEAP, dst, noreg, noreg, noreg);
}
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 {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "should be real oop");
}
#endif
oop_index = oop_recorder()->find_index(obj);
}
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) {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "not an oop");
}
#endif
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) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
bs->tlab_allocate(this, obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
}
// 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) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
bs->eden_allocate(this, obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case);
}
// Zero words; len is in bytes
// Destroys all registers except addr
// len must be a nonzero multiple of wordSize
void MacroAssembler::zero_memory(Register addr, Register len, Register t1) {
assert_different_registers(addr, len, t1, rscratch1, rscratch2);
#ifdef ASSERT
{ Label L;
tst(len, BytesPerWord - 1);
br(Assembler::EQ, L);
stop("len is not a multiple of BytesPerWord");
bind(L);
}
#endif
#ifndef PRODUCT
block_comment("zero memory");
#endif
Label loop;
Label entry;
// Algorithm:
//
// scratch1 = cnt & 7;
// cnt -= scratch1;
// p += scratch1;
// switch (scratch1) {
// do {
// cnt -= 8;
// p[-8] = 0;
// case 7:
// p[-7] = 0;
// case 6:
// p[-6] = 0;
// // ...
// case 1:
// p[-1] = 0;
// case 0:
// p += 8;
// } while (cnt);
// }
const int unroll = 8; // Number of str(zr) instructions we'll unroll
lsr(len, len, LogBytesPerWord);
andr(rscratch1, len, unroll - 1); // tmp1 = cnt % unroll
sub(len, len, rscratch1); // cnt -= unroll
// t1 always points to the end of the region we're about to zero
add(t1, addr, rscratch1, Assembler::LSL, LogBytesPerWord);
adr(rscratch2, entry);
sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 2);
br(rscratch2);
bind(loop);
sub(len, len, unroll);
for (int i = -unroll; i < 0; i++)
Assembler::str(zr, Address(t1, i * wordSize));
bind(entry);
add(t1, t1, unroll * wordSize);
cbnz(len, loop);
}
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));
}
}
// Move the address of the polling page into dest.
void MacroAssembler::get_polling_page(Register dest, address page, relocInfo::relocType rtype) {
if (SafepointMechanism::uses_thread_local_poll()) {
ldr(dest, Address(rthread, Thread::polling_page_offset()));
} else {
unsigned long off;
adrp(dest, Address(page, rtype), off);
assert(off == 0, "polling page must be page aligned");
}
}
// Move the address of the polling page into r, then read the polling
// page.
address MacroAssembler::read_polling_page(Register r, address page, relocInfo::relocType rtype) {
get_polling_page(r, page, rtype);
return read_polling_page(r, rtype);
}
// Read the polling page. The address of the polling page must
// already be in r.
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) {
CardTable::CardValue* byte_map_base =
((CardTableBarrierSet*)(BarrierSet::barrier_set()))->card_table()->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);
// We expect offset to be zero with most collectors.
if (offset != 0) {
add(reg, reg, offset);
}
} 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)));
}
}
#ifdef COMPILER2
typedef void (MacroAssembler::* chr_insn)(Register Rt, const Address &adr);
// 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,
Register tmp5, Register tmp6,
int icnt1, Register result, int ae) {
// NOTE: tmp5, tmp6 can be zr depending on specific method version
Label LINEARSEARCH, LINEARSTUB, LINEAR_MEDIUM, 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;
bool isL = ae == StrIntrinsicNode::LL;
bool str1_isL = ae == StrIntrinsicNode::LL || ae == StrIntrinsicNode::UL;
bool str2_isL = ae == StrIntrinsicNode::LL || ae == StrIntrinsicNode::LU;
int str1_chr_shift = str1_isL ? 0:1;
int str2_chr_shift = str2_isL ? 0:1;
int str1_chr_size = str1_isL ? 1:2;
int str2_chr_size = str2_isL ? 1:2;
chr_insn str1_load_1chr = str1_isL ? (chr_insn)&MacroAssembler::ldrb :
(chr_insn)&MacroAssembler::ldrh;
chr_insn str2_load_1chr = str2_isL ? (chr_insn)&MacroAssembler::ldrb :
(chr_insn)&MacroAssembler::ldrh;
chr_insn load_2chr = isL ? (chr_insn)&MacroAssembler::ldrh : (chr_insn)&MacroAssembler::ldrw;
chr_insn load_4chr = isL ? (chr_insn)&MacroAssembler::ldrw : (chr_insn)&MacroAssembler::ldr;
// 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) {
sub(result_tmp, cnt2, cnt1);
cmp(cnt1, (u1)8); // Use Linear Scan if cnt1 < 8 || cnt1 >= 256
br(LT, LINEARSEARCH);
dup(v0, T16B, cnt1); // done in separate FPU pipeline. Almost no penalty
subs(zr, cnt1, 256);
lsr(tmp1, cnt2, 2);
ccmp(cnt1, tmp1, 0b0000, LT); // Source must be 4 * pattern for BM
br(GE, LINEARSTUB);
}
// 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
//
// This particular implementation has few java-specific optimizations.
//
// #define ASIZE 256
//
// 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] = m;
// for (i = 0; i < m - 1; ) {
// c = x[i];
// ++i;
// // c < 256 for Latin1 string, so, no need for branch
// #ifdef PATTERN_STRING_IS_LATIN1
// bc[c] = m - i;
// #else
// if (c < ASIZE) bc[c] = m - i;
// #endif
// }
//
// /* 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;
// // c < 256 for Latin1 string, so, no need for branch
// #ifdef SOURCE_STRING_IS_LATIN1
// // LL case: (c< 256) always true. Remove branch
// j += bc[y[j+m-1]];
// #endif
// #ifndef PATTERN_STRING_IS_UTF
// // UU case: need if (c<ASIZE) check. Skip 1 character if not.
// if (c < ASIZE)
// j += bc[y[j+m-1]];
// else
// j += 1
// #endif
// #ifdef PATTERN_IS_LATIN1_AND_SOURCE_IS_UTF
// // UL case: need if (c<ASIZE) check. Skip <pattern length> if not.
// if (c < ASIZE)
// j += bc[y[j+m-1]];
// else
// j += m
// #endif
// }
// }
if (icnt1 == -1) {
Label BCLOOP, BCSKIP, BMLOOPSTR2, BMLOOPSTR1, BMSKIP, BMADV, BMMATCH,
BMLOOPSTR1_LASTCMP, BMLOOPSTR1_CMP, BMLOOPSTR1_AFTER_LOAD, BM_INIT_LOOP;
Register cnt1end = tmp2;
Register str2end = cnt2;
Register skipch = tmp2;
// str1 length is >=8, so, we can read at least 1 register for cases when
// UTF->Latin1 conversion is not needed(8 LL or 4UU) and half register for
// UL case. We'll re-read last character in inner pre-loop code to have
// single outer pre-loop load
const int firstStep = isL ? 7 : 3;
const int ASIZE = 256;
const int STORED_BYTES = 32; // amount of bytes stored per instruction
sub(sp, sp, ASIZE);
mov(tmp5, ASIZE/STORED_BYTES); // loop iterations
mov(ch1, sp);
BIND(BM_INIT_LOOP);
stpq(v0, v0, Address(post(ch1, STORED_BYTES)));
subs(tmp5, tmp5, 1);
br(GT, BM_INIT_LOOP);
sub(cnt1tmp, cnt1, 1);
mov(tmp5, str2);
add(str2end, str2, result_tmp, LSL, str2_chr_shift);
sub(ch2, cnt1, 1);
mov(tmp3, str1);
BIND(BCLOOP);
(this->*str1_load_1chr)(ch1, Address(post(tmp3, str1_chr_size)));
if (!str1_isL) {
subs(zr, ch1, ASIZE);
br(HS, BCSKIP);
}
strb(ch2, Address(sp, ch1));
BIND(BCSKIP);
subs(ch2, ch2, 1);
br(GT, BCLOOP);
add(tmp6, str1, cnt1, LSL, str1_chr_shift); // address after str1
if (str1_isL == str2_isL) {
// load last 8 bytes (8LL/4UU symbols)
ldr(tmp6, Address(tmp6, -wordSize));
} else {
ldrw(tmp6, Address(tmp6, -wordSize/2)); // load last 4 bytes(4 symbols)
// convert Latin1 to UTF. We'll have to wait until load completed, but
// it's still faster than per-character loads+checks
lsr(tmp3, tmp6, BitsPerByte * (wordSize/2 - str1_chr_size)); // str1[N-1]
ubfx(ch1, tmp6, 8, 8); // str1[N-2]
ubfx(ch2, tmp6, 16, 8); // str1[N-3]
andr(tmp6, tmp6, 0xFF); // str1[N-4]
orr(ch2, ch1, ch2, LSL, 16);
orr(tmp6, tmp6, tmp3, LSL, 48);
orr(tmp6, tmp6, ch2, LSL, 16);
}
BIND(BMLOOPSTR2);
(this->*str2_load_1chr)(skipch, Address(str2, cnt1tmp, Address::lsl(str2_chr_shift)));
sub(cnt1tmp, cnt1tmp, firstStep); // cnt1tmp is positive here, because cnt1 >= 8
if (str1_isL == str2_isL) {
// re-init tmp3. It's for free because it's executed in parallel with
// load above. Alternative is to initialize it before loop, but it'll
// affect performance on in-order systems with 2 or more ld/st pipelines
lsr(tmp3, tmp6, BitsPerByte * (wordSize - str1_chr_size));
}
if (!isL) { // UU/UL case
lsl(ch2, cnt1tmp, 1); // offset in bytes
}
cmp(tmp3, skipch);
br(NE, BMSKIP);
ldr(ch2, Address(str2, isL ? cnt1tmp : ch2));
mov(ch1, tmp6);
if (isL) {
b(BMLOOPSTR1_AFTER_LOAD);
} else {
sub(cnt1tmp, cnt1tmp, 1); // no need to branch for UU/UL case. cnt1 >= 8
b(BMLOOPSTR1_CMP);
}
BIND(BMLOOPSTR1);
(this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp, Address::lsl(str1_chr_shift)));
(this->*str2_load_1chr)(ch2, Address(str2, cnt1tmp, Address::lsl(str2_chr_shift)));
BIND(BMLOOPSTR1_AFTER_LOAD);
subs(cnt1tmp, cnt1tmp, 1);
br(LT, BMLOOPSTR1_LASTCMP);
BIND(BMLOOPSTR1_CMP);
cmp(ch1, ch2);
br(EQ, BMLOOPSTR1);
BIND(BMSKIP);
if (!isL) {
// if we've met UTF symbol while searching Latin1 pattern, then we can
// skip cnt1 symbols
if (str1_isL != str2_isL) {
mov(result_tmp, cnt1);
} else {
mov(result_tmp, 1);
}
subs(zr, skipch, ASIZE);
br(HS, BMADV);
}
ldrb(result_tmp, Address(sp, skipch)); // load skip distance
BIND(BMADV);
sub(cnt1tmp, cnt1, 1);
add(str2, str2, result_tmp, LSL, str2_chr_shift);
cmp(str2, str2end);
br(LE, BMLOOPSTR2);
add(sp, sp, ASIZE);
b(NOMATCH);
BIND(BMLOOPSTR1_LASTCMP);
cmp(ch1, ch2);
br(NE, BMSKIP);
BIND(BMMATCH);
sub(result, str2, tmp5);
if (!str2_isL) lsr(result, result, 1);
add(sp, sp, ASIZE);
b(DONE);
BIND(LINEARSTUB);
cmp(cnt1, (u1)16); // small patterns still should be handled by simple algorithm
br(LT, LINEAR_MEDIUM);
mov(result, zr);
RuntimeAddress stub = NULL;
if (isL) {
stub = RuntimeAddress(StubRoutines::aarch64::string_indexof_linear_ll());
assert(stub.target() != NULL, "string_indexof_linear_ll stub has not been generated");
} else if (str1_isL) {
stub = RuntimeAddress(StubRoutines::aarch64::string_indexof_linear_ul());
assert(stub.target() != NULL, "string_indexof_linear_ul stub has not been generated");
} else {
stub = RuntimeAddress(StubRoutines::aarch64::string_indexof_linear_uu());
assert(stub.target() != NULL, "string_indexof_linear_uu stub has not been generated");
}
trampoline_call(stub);
b(DONE);
}
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;
cmp(cnt1, u1(str1_isL == str2_isL ? 4 : 2));
br(LT, DOSHORT);
BIND(LINEAR_MEDIUM);
(this->*str1_load_1chr)(first, Address(str1));
lea(str1, Address(str1, cnt1, Address::lsl(str1_chr_shift)));
sub(cnt1_neg, zr, cnt1, LSL, str1_chr_shift);
lea(str2, Address(str2, result_tmp, Address::lsl(str2_chr_shift)));
sub(cnt2_neg, zr, result_tmp, LSL, str2_chr_shift);
BIND(FIRST_LOOP);
(this->*str2_load_1chr)(ch2, Address(str2, cnt2_neg));
cmp(first, ch2);
br(EQ, STR1_LOOP);
BIND(STR2_NEXT);
adds(cnt2_neg, cnt2_neg, str2_chr_size);
br(LE, FIRST_LOOP);
b(NOMATCH);
BIND(STR1_LOOP);
adds(cnt1tmp, cnt1_neg, str1_chr_size);
add(cnt2tmp, cnt2_neg, str2_chr_size);
br(GE, MATCH);
BIND(STR1_NEXT);
(this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp));
(this->*str2_load_1chr)(ch2, Address(str2, cnt2tmp));
cmp(ch1, ch2);
br(NE, STR2_NEXT);
adds(cnt1tmp, cnt1tmp, str1_chr_size);
add(cnt2tmp, cnt2tmp, str2_chr_size);
br(LT, STR1_NEXT);
b(MATCH);
BIND(DOSHORT);
if (str1_isL == str2_isL) {
cmp(cnt1, (u1)2);
br(LT, DO1);
br(GT, DO3);
}
}
if (icnt1 == 4) {
Label CH1_LOOP;
(this->*load_4chr)(ch1, str1);
sub(result_tmp, cnt2, 4);
lea(str2, Address(str2, result_tmp, Address::lsl(str2_chr_shift)));
sub(cnt2_neg, zr, result_tmp, LSL, str2_chr_shift);
BIND(CH1_LOOP);
(this->*load_4chr)(ch2, Address(str2, cnt2_neg));
cmp(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, str2_chr_size);
br(LE, CH1_LOOP);
b(NOMATCH);
}
if ((icnt1 == -1 && str1_isL == str2_isL) || icnt1 == 2) {
Label CH1_LOOP;
BIND(DO2);
(this->*load_2chr)(ch1, str1);
if (icnt1 == 2) {
sub(result_tmp, cnt2, 2);
}
lea(str2, Address(str2, result_tmp, Address::lsl(str2_chr_shift)));
sub(cnt2_neg, zr, result_tmp, LSL, str2_chr_shift);
BIND(CH1_LOOP);
(this->*load_2chr)(ch2, Address(str2, cnt2_neg));
cmp(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, str2_chr_size);
br(LE, CH1_LOOP);
b(NOMATCH);
}
if ((icnt1 == -1 && str1_isL == str2_isL) || icnt1 == 3) {
Label FIRST_LOOP, STR2_NEXT, STR1_LOOP;
BIND(DO3);
(this->*load_2chr)(first, str1);
(this->*str1_load_1chr)(ch1, Address(str1, 2*str1_chr_size));
if (icnt1 == 3) {
sub(result_tmp, cnt2, 3);
}
lea(str2, Address(str2, result_tmp, Address::lsl(str2_chr_shift)));
sub(cnt2_neg, zr, result_tmp, LSL, str2_chr_shift);
BIND(FIRST_LOOP);
(this->*load_2chr)(ch2, Address(str2, cnt2_neg));
cmpw(first, ch2);
br(EQ, STR1_LOOP);
BIND(STR2_NEXT);
adds(cnt2_neg, cnt2_neg, str2_chr_size);
br(LE, FIRST_LOOP);
b(NOMATCH);
BIND(STR1_LOOP);
add(cnt2tmp, cnt2_neg, 2*str2_chr_size);
(this->*str2_load_1chr)(ch2, Address(str2, cnt2tmp));
cmp(ch1, ch2);
br(NE, STR2_NEXT);
b(MATCH);
}
if (icnt1 == -1 || icnt1 == 1) {
Label CH1_LOOP, HAS_ZERO, DO1_SHORT, DO1_LOOP;
BIND(DO1);
(this->*str1_load_1chr)(ch1, str1);
cmp(cnt2, (u1)8);
br(LT, DO1_SHORT);
sub(result_tmp, cnt2, 8/str2_chr_size);
sub(cnt2_neg, zr, result_tmp, LSL, str2_chr_shift);
mov(tmp3, str2_isL ? 0x0101010101010101 : 0x0001000100010001);
lea(str2, Address(str2, result_tmp, Address::lsl(str2_chr_shift)));
if (str2_isL) {
orr(ch1, ch1, ch1, LSL, 8);
}
orr(ch1, ch1, ch1, LSL, 16);
orr(ch1, ch1, ch1, LSL, 32);
BIND(CH1_LOOP);
ldr(ch2, Address(str2, cnt2_neg));
eor(ch2, ch1, ch2);
sub(tmp1, ch2, tmp3);
orr(tmp2, ch2, str2_isL ? 0x7f7f7f7f7f7f7f7f : 0x7fff7fff7fff7fff);
bics(tmp1, tmp1, tmp2);
br(NE, HAS_ZERO);
adds(cnt2_neg, cnt2_neg, 8);
br(LT, CH1_LOOP);
cmp(cnt2_neg, (u1)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::lsl(str2_chr_shift)));
sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
BIND(DO1_LOOP);
(this->*str2_load_1chr)(ch2, Address(str2, cnt2_neg));
cmpw(ch1, ch2);
br(EQ, MATCH);
adds(cnt2_neg, cnt2_neg, str2_chr_size);
br(LT, DO1_LOOP);
}
}
BIND(NOMATCH);
mov(result, -1);
b(DONE);
BIND(MATCH);
add(result, result_tmp, cnt2_neg, ASR, str2_chr_shift);
BIND(DONE);
}
typedef void (MacroAssembler::* chr_insn)(Register Rt, const Address &adr);
typedef void (MacroAssembler::* uxt_insn)(Register Rd, Register Rn);
void MacroAssembler::string_indexof_char(Register str1, Register cnt1,
Register ch, Register result,
Register tmp1, Register tmp2, Register tmp3)
{
Label CH1_LOOP, HAS_ZERO, DO1_SHORT, DO1_LOOP, MATCH, NOMATCH, DONE;
Register cnt1_neg = cnt1;
Register ch1 = rscratch1;
Register result_tmp = rscratch2;
cmp(cnt1, (u1)4);
br(LT, DO1_SHORT);
orr(ch, ch, ch, LSL, 16);
orr(ch, ch, ch, LSL, 32);
sub(cnt1, cnt1, 4);
mov(result_tmp, cnt1);
lea(str1, Address(str1, cnt1, Address::uxtw(1)));
sub(cnt1_neg, zr, cnt1, LSL, 1);
mov(tmp3, 0x0001000100010001);
BIND(CH1_LOOP);
ldr(ch1, Address(str1, cnt1_neg));
eor(ch1, ch, ch1);
sub(tmp1, ch1, tmp3);
orr(tmp2, ch1, 0x7fff7fff7fff7fff);
bics(tmp1, tmp1, tmp2);
br(NE, HAS_ZERO);
adds(cnt1_neg, cnt1_neg, 8);
br(LT, CH1_LOOP);
cmp(cnt1_neg, (u1)8);
mov(cnt1_neg, 0);
br(LT, CH1_LOOP);
b(NOMATCH);
BIND(HAS_ZERO);
rev(tmp1, tmp1);
clz(tmp1, tmp1);
add(cnt1_neg, cnt1_neg, tmp1, LSR, 3);
b(MATCH);
BIND(DO1_SHORT);
mov(result_tmp, cnt1);
lea(str1, Address(str1, cnt1, Address::uxtw(1)));
sub(cnt1_neg, zr, cnt1, LSL, 1);
BIND(DO1_LOOP);
ldrh(ch1, Address(str1, cnt1_neg));
cmpw(ch, ch1);
br(EQ, MATCH);
adds(cnt1_neg, cnt1_neg, 2);
br(LT, DO1_LOOP);
BIND(NOMATCH);
mov(result, -1);
b(DONE);
BIND(MATCH);
add(result, result_tmp, cnt1_neg, ASR, 1);
BIND(DONE);
}
// Compare strings.
void MacroAssembler::string_compare(Register str1, Register str2,
Register cnt1, Register cnt2, Register result, Register tmp1, Register tmp2,
FloatRegister vtmp1, FloatRegister vtmp2, FloatRegister vtmp3, int ae) {
Label DONE, SHORT_LOOP, SHORT_STRING, SHORT_LAST, TAIL, STUB,
DIFFERENCE, NEXT_WORD, SHORT_LOOP_TAIL, SHORT_LAST2, SHORT_LAST_INIT,
SHORT_LOOP_START, TAIL_CHECK;
const u1 STUB_THRESHOLD = 64 + 8;
bool isLL = ae == StrIntrinsicNode::LL;
bool isLU = ae == StrIntrinsicNode::LU;
bool isUL = ae == StrIntrinsicNode::UL;
bool str1_isL = isLL || isLU;
bool str2_isL = isLL || isUL;
int str1_chr_shift = str1_isL ? 0 : 1;
int str2_chr_shift = str2_isL ? 0 : 1;
int str1_chr_size = str1_isL ? 1 : 2;
int str2_chr_size = str2_isL ? 1 : 2;
int minCharsInWord = isLL ? wordSize : wordSize/2;
FloatRegister vtmpZ = vtmp1, vtmp = vtmp2;
chr_insn str1_load_chr = str1_isL ? (chr_insn)&MacroAssembler::ldrb :
(chr_insn)&MacroAssembler::ldrh;
chr_insn str2_load_chr = str2_isL ? (chr_insn)&MacroAssembler::ldrb :
(chr_insn)&MacroAssembler::ldrh;
uxt_insn ext_chr = isLL ? (uxt_insn)&MacroAssembler::uxtbw :
(uxt_insn)&MacroAssembler::uxthw;
BLOCK_COMMENT("string_compare {");
// Bizzarely, the counts are passed in bytes, regardless of whether they
// are L or U strings, however the result is always in characters.
if (!str1_isL) asrw(cnt1, cnt1, 1);
if (!str2_isL) asrw(cnt2, cnt2, 1);
// Compute the minimum of the string lengths and save the difference.
subsw(result, cnt1, cnt2);
cselw(cnt2, cnt1, cnt2, Assembler::LE); // min
// A very short string
cmpw(cnt2, minCharsInWord);
br(Assembler::LE, SHORT_STRING);
// Compare longwords
// load first parts of strings and finish initialization while loading
{
if (str1_isL == str2_isL) { // LL or UU
ldr(tmp1, Address(str1));
cmp(str1, str2);
br(Assembler::EQ, DONE);
ldr(tmp2, Address(str2));
cmp(cnt2, STUB_THRESHOLD);
br(GE, STUB);
subsw(cnt2, cnt2, minCharsInWord);
br(EQ, TAIL_CHECK);
lea(str2, Address(str2, cnt2, Address::uxtw(str2_chr_shift)));
lea(str1, Address(str1, cnt2, Address::uxtw(str1_chr_shift)));
sub(cnt2, zr, cnt2, LSL, str2_chr_shift);
} else if (isLU) {
ldrs(vtmp, Address(str1));
cmp(str1, str2);
br(Assembler::EQ, DONE);
ldr(tmp2, Address(str2));
cmp(cnt2, STUB_THRESHOLD);
br(GE, STUB);
subw(cnt2, cnt2, 4);
eor(vtmpZ, T16B, vtmpZ, vtmpZ);
lea(str1, Address(str1, cnt2, Address::uxtw(str1_chr_shift)));
lea(str2, Address(str2, cnt2, Address::uxtw(str2_chr_shift)));
zip1(vtmp, T8B, vtmp, vtmpZ);
sub(cnt1, zr, cnt2, LSL, str1_chr_shift);
sub(cnt2, zr, cnt2, LSL, str2_chr_shift);
add(cnt1, cnt1, 4);
fmovd(tmp1, vtmp);
} else { // UL case
ldr(tmp1, Address(str1));
cmp(str1, str2);
br(Assembler::EQ, DONE);
ldrs(vtmp, Address(str2));
cmp(cnt2, STUB_THRESHOLD);
br(GE, STUB);
subw(cnt2, cnt2, 4);
lea(str1, Address(str1, cnt2, Address::uxtw(str1_chr_shift)));
eor(vtmpZ, T16B, vtmpZ, vtmpZ);
lea(str2, Address(str2, cnt2, Address::uxtw(str2_chr_shift)));
sub(cnt1, zr, cnt2, LSL, str1_chr_shift);
zip1(vtmp, T8B, vtmp, vtmpZ);
sub(cnt2, zr, cnt2, LSL, str2_chr_shift);
add(cnt1, cnt1, 8);
fmovd(tmp2, vtmp);
}
adds(cnt2, cnt2, isUL ? 4 : 8);
br(GE, TAIL);
eor(rscratch2, tmp1, tmp2);
cbnz(rscratch2, DIFFERENCE);
// main loop
bind(NEXT_WORD);
if (str1_isL == str2_isL) {
ldr(tmp1, Address(str1, cnt2));
ldr(tmp2, Address(str2, cnt2));
adds(cnt2, cnt2, 8);
} else if (isLU) {
ldrs(vtmp, Address(str1, cnt1));
ldr(tmp2, Address(str2, cnt2));
add(cnt1, cnt1, 4);
zip1(vtmp, T8B, vtmp, vtmpZ);
fmovd(tmp1, vtmp);
adds(cnt2, cnt2, 8);
} else { // UL
ldrs(vtmp, Address(str2, cnt2));
ldr(tmp1, Address(str1, cnt1));
zip1(vtmp, T8B, vtmp, vtmpZ);
add(cnt1, cnt1, 8);
fmovd(tmp2, vtmp);
adds(cnt2, cnt2, 4);
}
br(GE, TAIL);
eor(rscratch2, tmp1, tmp2);
cbz(rscratch2, NEXT_WORD);
b(DIFFERENCE);
bind(TAIL);
eor(rscratch2, tmp1, tmp2);
cbnz(rscratch2, DIFFERENCE);
// Last longword. In the case where length == 4 we compare the
// same longword twice, but that's still faster than another
// conditional branch.
if (str1_isL == str2_isL) {
ldr(tmp1, Address(str1));
ldr(tmp2, Address(str2));
} else if (isLU) {
ldrs(vtmp, Address(str1));
ldr(tmp2, Address(str2));
zip1(vtmp, T8B, vtmp, vtmpZ);
fmovd(tmp1, vtmp);
} else { // UL
ldrs(vtmp, Address(str2));
ldr(tmp1, Address(str1));
zip1(vtmp, T8B, vtmp, vtmpZ);
fmovd(tmp2, vtmp);
}
bind(TAIL_CHECK);
eor(rscratch2, tmp1, tmp2);
cbz(rscratch2, DONE);
// Find the first different characters in the longwords and
// compute their difference.
bind(DIFFERENCE);
rev(rscratch2, rscratch2);
clz(rscratch2, rscratch2);
andr(rscratch2, rscratch2, isLL ? -8 : -16);
lsrv(tmp1, tmp1, rscratch2);
(this->*ext_chr)(tmp1, tmp1);
lsrv(tmp2, tmp2, rscratch2);
(this->*ext_chr)(tmp2, tmp2);
subw(result, tmp1, tmp2);
b(DONE);
}
bind(STUB);
RuntimeAddress stub = NULL;
switch(ae) {
case StrIntrinsicNode::LL:
stub = RuntimeAddress(StubRoutines::aarch64::compare_long_string_LL());
break;
case StrIntrinsicNode::UU:
stub = RuntimeAddress(StubRoutines::aarch64::compare_long_string_UU());
break;
case StrIntrinsicNode::LU:
stub = RuntimeAddress(StubRoutines::aarch64::compare_long_string_LU());
break;
case StrIntrinsicNode::UL:
stub = RuntimeAddress(StubRoutines::aarch64::compare_long_string_UL());
break;
default:
ShouldNotReachHere();
}
assert(stub.target() != NULL, "compare_long_string stub has not been generated");
trampoline_call(stub);
b(DONE);
bind(SHORT_STRING);
// Is the minimum length zero?
cbz(cnt2, DONE);
// arrange code to do most branches while loading and loading next characters
// while comparing previous
(this->*str1_load_chr)(tmp1, Address(post(str1, str1_chr_size)));
subs(cnt2, cnt2, 1);
br(EQ, SHORT_LAST_INIT);
(this->*str2_load_chr)(cnt1, Address(post(str2, str2_chr_size)));
b(SHORT_LOOP_START);
bind(SHORT_LOOP);
subs(cnt2, cnt2, 1);
br(EQ, SHORT_LAST);
bind(SHORT_LOOP_START);
(this->*str1_load_chr)(tmp2, Address(post(str1, str1_chr_size)));
(this->*str2_load_chr)(rscratch1, Address(post(str2, str2_chr_size)));
cmp(tmp1, cnt1);
br(NE, SHORT_LOOP_TAIL);
subs(cnt2, cnt2, 1);
br(EQ, SHORT_LAST2);
(this->*str1_load_chr)(tmp1, Address(post(str1, str1_chr_size)));
(this->*str2_load_chr)(cnt1, Address(post(str2, str2_chr_size)));
cmp(tmp2, rscratch1);
br(EQ, SHORT_LOOP);
sub(result, tmp2, rscratch1);
b(DONE);
bind(SHORT_LOOP_TAIL);
sub(result, tmp1, cnt1);
b(DONE);
bind(SHORT_LAST2);
cmp(tmp2, rscratch1);
br(EQ, DONE);
sub(result, tmp2, rscratch1);
b(DONE);
bind(SHORT_LAST_INIT);
(this->*str2_load_chr)(cnt1, Address(post(str2, str2_chr_size)));
bind(SHORT_LAST);
cmp(tmp1, cnt1);
br(EQ, DONE);
sub(result, tmp1, cnt1);
bind(DONE);
BLOCK_COMMENT("} string_compare");
}
#endif // COMPILER2
// This method checks if provided byte array contains byte with highest bit set.
void MacroAssembler::has_negatives(Register ary1, Register len, Register result) {
// Simple and most common case of aligned small array which is not at the
// end of memory page is placed here. All other cases are in stub.
Label LOOP, END, STUB, STUB_LONG, SET_RESULT, DONE;
const uint64_t UPPER_BIT_MASK=0x8080808080808080;
assert_different_registers(ary1, len, result);
cmpw(len, 0);
br(LE, SET_RESULT);
cmpw(len, 4 * wordSize);
br(GE, STUB_LONG); // size > 32 then go to stub
int shift = 64 - exact_log2(os::vm_page_size());
lsl(rscratch1, ary1, shift);
mov(rscratch2, (size_t)(4 * wordSize) << shift);
adds(rscratch2, rscratch1, rscratch2); // At end of page?
br(CS, STUB); // at the end of page then go to stub
subs(len, len, wordSize);
br(LT, END);
BIND(LOOP);
ldr(rscratch1, Address(post(ary1, wordSize)));
tst(rscratch1, UPPER_BIT_MASK);
br(NE, SET_RESULT);
subs(len, len, wordSize);
br(GE, LOOP);
cmpw(len, -wordSize);
br(EQ, SET_RESULT);
BIND(END);
ldr(result, Address(ary1));
sub(len, zr, len, LSL, 3); // LSL 3 is to get bits from bytes
lslv(result, result, len);
tst(result, UPPER_BIT_MASK);
b(SET_RESULT);
BIND(STUB);
RuntimeAddress has_neg = RuntimeAddress(StubRoutines::aarch64::has_negatives());
assert(has_neg.target() != NULL, "has_negatives stub has not been generated");
trampoline_call(has_neg);
b(DONE);
BIND(STUB_LONG);
RuntimeAddress has_neg_long = RuntimeAddress(
StubRoutines::aarch64::has_negatives_long());
assert(has_neg_long.target() != NULL, "has_negatives stub has not been generated");
trampoline_call(has_neg_long);
b(DONE);
BIND(SET_RESULT);
cset(result, NE); // set true or false
BIND(DONE);
}
void MacroAssembler::arrays_equals(Register a1, Register a2, Register tmp3,
Register tmp4, Register tmp5, Register result,
Register cnt1, int elem_size) {
Label DONE, SAME;
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);
int stubBytesThreshold = 3 * 64 + (UseSIMDForArrayEquals ? 0 : 16);
assert(elem_size == 1 || elem_size == 2, "must be char or byte");
assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
#ifndef PRODUCT
{
const char kind = (elem_size == 2) ? 'U' : 'L';
char comment[64];
snprintf(comment, sizeof comment, "array_equals%c{", kind);
BLOCK_COMMENT(comment);
}
#endif
// if (a1 == a2)
// return true;
cmpoop(a1, a2); // May have read barriers for a1 and a2.
br(EQ, SAME);
if (UseSimpleArrayEquals) {
Label NEXT_WORD, SHORT, TAIL03, TAIL01, A_MIGHT_BE_NULL, A_IS_NOT_NULL;
// if (a1 == null || a2 == null)
// return false;
// a1 & a2 == 0 means (some-pointer is null) or
// (very-rare-or-even-probably-impossible-pointer-values)
// so, we can save one branch in most cases
tst(a1, a2);
mov(result, false);
br(EQ, A_MIGHT_BE_NULL);
// if (a1.length != a2.length)
// return false;
bind(A_IS_NOT_NULL);
ldrw(cnt1, Address(a1, length_offset));
ldrw(cnt2, Address(a2, length_offset));
eorw(tmp5, cnt1, cnt2);
cbnzw(tmp5, 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(tmp5, tmp1, tmp2);
cbnz(tmp5, 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(tmp3, Address(a1, cnt1));
ldr(tmp4, Address(a2, cnt1));
eor(tmp5, tmp3, tmp4);
cbnz(tmp5, DONE);
b(SAME);
bind(A_MIGHT_BE_NULL);
// in case both a1 and a2 are not-null, proceed with loads
cbz(a1, DONE);
cbz(a2, DONE);
b(A_IS_NOT_NULL);
bind(SHORT);
tbz(cnt1, 2 - log_elem_size, TAIL03); // 0-7 bytes left.
{
ldrw(tmp1, Address(post(a1, 4)));
ldrw(tmp2, Address(post(a2, 4)));
eorw(tmp5, tmp1, tmp2);
cbnzw(tmp5, DONE);
}
bind(TAIL03);
tbz(cnt1, 1 - log_elem_size, TAIL01); // 0-3 bytes left.
{
ldrh(tmp3, Address(post(a1, 2)));
ldrh(tmp4, Address(post(a2, 2)));
eorw(tmp5, tmp3, tmp4);
cbnzw(tmp5, 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(tmp5, tmp1, tmp2);
cbnzw(tmp5, DONE);
}
}
} else {
Label NEXT_DWORD, SHORT, TAIL, TAIL2, STUB, EARLY_OUT,
CSET_EQ, LAST_CHECK;
mov(result, false);
cbz(a1, DONE);
ldrw(cnt1, Address(a1, length_offset));
cbz(a2, DONE);
ldrw(cnt2, Address(a2, length_offset));
// on most CPUs a2 is still "locked"(surprisingly) in ldrw and it's
// faster to perform another branch before comparing a1 and a2
cmp(cnt1, (u1)elem_per_word);
br(LE, SHORT); // short or same
ldr(tmp3, Address(pre(a1, base_offset)));
subs(zr, cnt1, stubBytesThreshold);
br(GE, STUB);
ldr(tmp4, Address(pre(a2, base_offset)));
sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
cmp(cnt2, cnt1);
br(NE, DONE);
// Main 16 byte comparison loop with 2 exits
bind(NEXT_DWORD); {
ldr(tmp1, Address(pre(a1, wordSize)));
ldr(tmp2, Address(pre(a2, wordSize)));
subs(cnt1, cnt1, 2 * elem_per_word);
br(LE, TAIL);
eor(tmp4, tmp3, tmp4);
cbnz(tmp4, DONE);
ldr(tmp3, Address(pre(a1, wordSize)));
ldr(tmp4, Address(pre(a2, wordSize)));
cmp(cnt1, (u1)elem_per_word);
br(LE, TAIL2);
cmp(tmp1, tmp2);
} br(EQ, NEXT_DWORD);
b(DONE);
bind(TAIL);
eor(tmp4, tmp3, tmp4);
eor(tmp2, tmp1, tmp2);
lslv(tmp2, tmp2, tmp5);
orr(tmp5, tmp4, tmp2);
cmp(tmp5, zr);
b(CSET_EQ);
bind(TAIL2);
eor(tmp2, tmp1, tmp2);
cbnz(tmp2, DONE);
b(LAST_CHECK);
bind(STUB);
ldr(tmp4, Address(pre(a2, base_offset)));
cmp(cnt2, cnt1);
br(NE, DONE);
if (elem_size == 2) { // convert to byte counter
lsl(cnt1, cnt1, 1);
}
eor(tmp5, tmp3, tmp4);
cbnz(tmp5, DONE);
RuntimeAddress stub = RuntimeAddress(StubRoutines::aarch64::large_array_equals());
assert(stub.target() != NULL, "array_equals_long stub has not been generated");
trampoline_call(stub);
b(DONE);
bind(EARLY_OUT);
// (a1 != null && a2 == null) || (a1 != null && a2 != null && a1 == a2)
// so, if a2 == null => return false(0), else return true, so we can return a2
mov(result, a2);
b(DONE);
bind(SHORT);
cmp(cnt2, cnt1);
br(NE, DONE);
cbz(cnt1, SAME);
sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
ldr(tmp3, Address(a1, base_offset));
ldr(tmp4, Address(a2, base_offset));
bind(LAST_CHECK);
eor(tmp4, tmp3, tmp4);
lslv(tmp5, tmp4, tmp5);
cmp(tmp5, zr);
bind(CSET_EQ);
cset(result, EQ);
b(DONE);
}
bind(SAME);
mov(result, true);
// That's it.
bind(DONE);
BLOCK_COMMENT("} array_equals");
}
// Compare Strings
// For Strings we're passed the address of the first characters in a1
// and a2 and the length in cnt1.
// 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 strings < 8 bytes, we compare a
// halfword, then a short, and then a byte.
void MacroAssembler::string_equals(Register a1, Register a2,
Register result, Register cnt1, int elem_size)
{
Label SAME, DONE, SHORT, NEXT_WORD;
Register tmp1 = rscratch1;
Register tmp2 = rscratch2;
Register cnt2 = tmp2; // cnt2 only used in array length compare
assert(elem_size == 1 || elem_size == 2, "must be 2 or 1 byte");
assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
#ifndef PRODUCT
{
const char kind = (elem_size == 2) ? 'U' : 'L';
char comment[64];
snprintf(comment, sizeof comment, "{string_equals%c", kind);
BLOCK_COMMENT(comment);
}
#endif
mov(result, false);
// Check for short strings, i.e. smaller than wordSize.
subs(cnt1, cnt1, wordSize);
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, wordSize);
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.
ldr(tmp1, Address(a1, cnt1));
ldr(tmp2, Address(a2, cnt1));
eor(tmp2, tmp1, tmp2);
cbnz(tmp2, DONE);
b(SAME);
bind(SHORT);
Label TAIL03, TAIL01;
tbz(cnt1, 2, 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, 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 1-byte elements
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("} string_equals");
}
// The size of the blocks erased by the zero_blocks stub. We must
// handle anything smaller than this ourselves in zero_words().
const int MacroAssembler::zero_words_block_size = 8;
// zero_words() is used by C2 ClearArray patterns. It is as small as
// possible, handling small word counts locally and delegating
// anything larger to the zero_blocks stub. It is expanded many times
// in compiled code, so it is important to keep it short.
// ptr: Address of a buffer to be zeroed.
// cnt: Count in HeapWords.
//
// ptr, cnt, rscratch1, and rscratch2 are clobbered.
void MacroAssembler::zero_words(Register ptr, Register cnt)
{
assert(is_power_of_2(zero_words_block_size), "adjust this");
assert(ptr == r10 && cnt == r11, "mismatch in register usage");
BLOCK_COMMENT("zero_words {");
cmp(cnt, (u1)zero_words_block_size);
Label around;
br(LO, around);
{
RuntimeAddress zero_blocks = RuntimeAddress(StubRoutines::aarch64::zero_blocks());
assert(zero_blocks.target() != NULL, "zero_blocks stub has not been generated");
if (StubRoutines::aarch64::complete()) {
trampoline_call(zero_blocks);
} else {
bl(zero_blocks);
}
}
bind(around);
for (int i = zero_words_block_size >> 1; i > 1; i >>= 1) {
Label l;
tbz(cnt, exact_log2(i), l);
for (int j = 0; j < i; j += 2) {
stp(zr, zr, post(ptr, 16));
}
bind(l);
}
{
Label l;
tbz(cnt, 0, l);
str(zr, Address(ptr));
bind(l);
}
BLOCK_COMMENT("} zero_words");
}
// base: Address of a buffer to be zeroed, 8 bytes aligned.
// cnt: Immediate count in HeapWords.
#define SmallArraySize (18 * BytesPerLong)
void MacroAssembler::zero_words(Register base, u_int64_t cnt)
{
BLOCK_COMMENT("zero_words {");
int i = cnt & 1; // store any odd word to start
if (i) str(zr, Address(base));
if (cnt <= SmallArraySize / BytesPerLong) {
for (; i < (int)cnt; i += 2)
stp(zr, zr, Address(base, i * wordSize));
} else {
const int unroll = 4; // Number of stp(zr, zr) instructions we'll unroll
int remainder = cnt % (2 * unroll);
for (; i < remainder; i += 2)
stp(zr, zr, Address(base, i * wordSize));
Label loop;
Register cnt_reg = rscratch1;
Register loop_base = rscratch2;
cnt = cnt - remainder;
mov(cnt_reg, cnt);
// adjust base and prebias by -2 * wordSize so we can pre-increment
add(loop_base, base, (remainder - 2) * wordSize);
bind(loop);
sub(cnt_reg, cnt_reg, 2 * unroll);
for (i = 1; i < unroll; i++)
stp(zr, zr, Address(loop_base, 2 * i * wordSize));
stp(zr, zr, Address(pre(loop_base, 2 * unroll * wordSize)));
cbnz(cnt_reg, loop);
}
BLOCK_COMMENT("} zero_words");
}
// Zero blocks of memory by using DC ZVA.
//
// Aligns the base address first sufficently for DC ZVA, then uses
// DC ZVA repeatedly for every full block. cnt is the size to be
// zeroed in HeapWords. Returns the count of words left to be zeroed
// in cnt.
//
// NOTE: This is intended to be used in the zero_blocks() stub. If
// you want to use it elsewhere, note that cnt must be >= 2*zva_length.
void MacroAssembler::zero_dcache_blocks(Register base, Register cnt) {
Register tmp = rscratch1;
Register tmp2 = rscratch2;
int zva_length = VM_Version::zva_length();
Label initial_table_end, loop_zva;
Label fini;
// Base must be 16 byte aligned. If not just return and let caller handle it
tst(base, 0x0f);
br(Assembler::NE, fini);
// Align base with ZVA length.
neg(tmp, base);
andr(tmp, tmp, zva_length - 1);
// tmp: the number of bytes to be filled to align the base with ZVA length.
add(base, base, tmp);
sub(cnt, cnt, tmp, Assembler::ASR, 3);
adr(tmp2, initial_table_end);
sub(tmp2, tmp2, tmp, Assembler::LSR, 2);
br(tmp2);
for (int i = -zva_length + 16; i < 0; i += 16)
stp(zr, zr, Address(base, i));
bind(initial_table_end);
sub(cnt, cnt, zva_length >> 3);
bind(loop_zva);
dc(Assembler::ZVA, base);
subs(cnt, cnt, zva_length >> 3);
add(base, base, zva_length);
br(Assembler::GE, loop_zva);
add(cnt, cnt, zva_length >> 3); // count not zeroed by DC ZVA
bind(fini);
}
// base: Address of a buffer to be filled, 8 bytes aligned.
// cnt: Count in 8-byte unit.
// value: Value to be filled with.
// base will point to the end of the buffer after filling.
void MacroAssembler::fill_words(Register base, Register cnt, Register value)
{
// Algorithm:
//
// scratch1 = cnt & 7;
// cnt -= scratch1;
// p += scratch1;
// switch (scratch1) {
// do {
// cnt -= 8;
// p[-8] = v;
// case 7:
// p[-7] = v;
// case 6:
// p[-6] = v;
// // ...
// case 1:
// p[-1] = v;
// case 0:
// p += 8;
// } while (cnt);
// }
assert_different_registers(base, cnt, value, rscratch1, rscratch2);
Label fini, skip, entry, loop;
const int unroll = 8; // Number of stp instructions we'll unroll
cbz(cnt, fini);
tbz(base, 3, skip);
str(value, Address(post(base, 8)));
sub(cnt, cnt, 1);
bind(skip);
andr(rscratch1, cnt, (unroll-1) * 2);
sub(cnt, cnt, rscratch1);
add(base, base, rscratch1, Assembler::LSL, 3);
adr(rscratch2, entry);
sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 1);
br(rscratch2);
bind(loop);
add(base, base, unroll * 16);
for (int i = -unroll; i < 0; i++)
stp(value, value, Address(base, i * 16));
bind(entry);
subs(cnt, cnt, unroll * 2);
br(Assembler::GE, loop);
tbz(cnt, 0, fini);
str(value, Address(post(base, 8)));
bind(fini);
}
// Intrinsic for sun/nio/cs/ISO_8859_1$Encoder.implEncodeISOArray and
// java/lang/StringUTF16.compress.
void MacroAssembler::encode_iso_array(Register src, Register dst,
Register len, Register result,
FloatRegister Vtmp1, FloatRegister Vtmp2,
FloatRegister Vtmp3, FloatRegister Vtmp4)
{
Label DONE, SET_RESULT, NEXT_32, NEXT_32_PRFM, LOOP_8, NEXT_8, LOOP_1, NEXT_1,
NEXT_32_START, NEXT_32_PRFM_START;
Register tmp1 = rscratch1, tmp2 = rscratch2;
mov(result, len); // Save initial len
cmp(len, (u1)8); // handle shortest strings first
br(LT, LOOP_1);
cmp(len, (u1)32);
br(LT, NEXT_8);
// The following code uses the SIMD 'uzp1' and 'uzp2' instructions
// to convert chars to bytes
if (SoftwarePrefetchHintDistance >= 0) {
ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
subs(tmp2, len, SoftwarePrefetchHintDistance/2 + 16);
br(LE, NEXT_32_START);
b(NEXT_32_PRFM_START);
BIND(NEXT_32_PRFM);
ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
BIND(NEXT_32_PRFM_START);
prfm(Address(src, SoftwarePrefetchHintDistance));
orr(v4, T16B, Vtmp1, Vtmp2);
orr(v5, T16B, Vtmp3, Vtmp4);
uzp1(Vtmp1, T16B, Vtmp1, Vtmp2);
uzp1(Vtmp3, T16B, Vtmp3, Vtmp4);
uzp2(v5, T16B, v4, v5); // high bytes
umov(tmp2, v5, D, 1);
fmovd(tmp1, v5);
orr(tmp1, tmp1, tmp2);
cbnz(tmp1, LOOP_8);
stpq(Vtmp1, Vtmp3, dst);
sub(len, len, 32);
add(dst, dst, 32);
add(src, src, 64);
subs(tmp2, len, SoftwarePrefetchHintDistance/2 + 16);
br(GE, NEXT_32_PRFM);
cmp(len, (u1)32);
br(LT, LOOP_8);
BIND(NEXT_32);
ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
BIND(NEXT_32_START);
} else {
BIND(NEXT_32);
ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
}
prfm(Address(src, SoftwarePrefetchHintDistance));
uzp1(v4, T16B, Vtmp1, Vtmp2);
uzp1(v5, T16B, Vtmp3, Vtmp4);
orr(Vtmp1, T16B, Vtmp1, Vtmp2);
orr(Vtmp3, T16B, Vtmp3, Vtmp4);
uzp2(Vtmp1, T16B, Vtmp1, Vtmp3); // high bytes
umov(tmp2, Vtmp1, D, 1);
fmovd(tmp1, Vtmp1);
orr(tmp1, tmp1, tmp2);
cbnz(tmp1, LOOP_8);
stpq(v4, v5, dst);
sub(len, len, 32);
add(dst, dst, 32);
add(src, src, 64);
cmp(len, (u1)32);
br(GE, NEXT_32);
cbz(len, DONE);
BIND(LOOP_8);
cmp(len, (u1)8);
br(LT, LOOP_1);
BIND(NEXT_8);
ld1(Vtmp1, T8H, src);
uzp1(Vtmp2, T16B, Vtmp1, Vtmp1); // low bytes
uzp2(Vtmp3, T16B, Vtmp1, Vtmp1); // high bytes
fmovd(tmp1, Vtmp3);
cbnz(tmp1, NEXT_1);
strd(Vtmp2, dst);
sub(len, len, 8);
add(dst, dst, 8);
add(src, src, 16);
cmp(len, (u1)8);
br(GE, NEXT_8);
BIND(LOOP_1);
cbz(len, DONE);
BIND(NEXT_1);
ldrh(tmp1, Address(post(src, 2)));
tst(tmp1, 0xff00);
br(NE, SET_RESULT);
strb(tmp1, Address(post(dst, 1)));
subs(len, len, 1);
br(GT, NEXT_1);
BIND(SET_RESULT);
sub(result, result, len); // Return index where we stopped
// Return len == 0 if we processed all
// characters
BIND(DONE);
}
// Inflate byte[] array to char[].
void MacroAssembler::byte_array_inflate(Register src, Register dst, Register len,
FloatRegister vtmp1, FloatRegister vtmp2, FloatRegister vtmp3,
Register tmp4) {
Label big, done, after_init, to_stub;
assert_different_registers(src, dst, len, tmp4, rscratch1);
fmovd(vtmp1, zr);
lsrw(tmp4, len, 3);
bind(after_init);
cbnzw(tmp4, big);
// Short string: less than 8 bytes.
{
Label loop, tiny;
cmpw(len, 4);
br(LT, tiny);
// Use SIMD to do 4 bytes.
ldrs(vtmp2, post(src, 4));
zip1(vtmp3, T8B, vtmp2, vtmp1);
subw(len, len, 4);
strd(vtmp3, post(dst, 8));
cbzw(len, done);
// Do the remaining bytes by steam.
bind(loop);
ldrb(tmp4, post(src, 1));
strh(tmp4, post(dst, 2));
subw(len, len, 1);
bind(tiny);
cbnz(len, loop);
b(done);
}
if (SoftwarePrefetchHintDistance >= 0) {
bind(to_stub);
RuntimeAddress stub = RuntimeAddress(StubRoutines::aarch64::large_byte_array_inflate());
assert(stub.target() != NULL, "large_byte_array_inflate stub has not been generated");
trampoline_call(stub);
b(after_init);
}
// Unpack the bytes 8 at a time.
bind(big);
{
Label loop, around, loop_last, loop_start;
if (SoftwarePrefetchHintDistance >= 0) {
const int large_loop_threshold = (64 + 16)/8;
ldrd(vtmp2, post(src, 8));
andw(len, len, 7);
cmp(tmp4, (u1)large_loop_threshold);
br(GE, to_stub);
b(loop_start);
bind(loop);
ldrd(vtmp2, post(src, 8));
bind(loop_start);
subs(tmp4, tmp4, 1);
br(EQ, loop_last);
zip1(vtmp2, T16B, vtmp2, vtmp1);
ldrd(vtmp3, post(src, 8));
st1(vtmp2, T8H, post(dst, 16));
subs(tmp4, tmp4, 1);
zip1(vtmp3, T16B, vtmp3, vtmp1);
st1(vtmp3, T8H, post(dst, 16));
br(NE, loop);
b(around);
bind(loop_last);
zip1(vtmp2, T16B, vtmp2, vtmp1);
st1(vtmp2, T8H, post(dst, 16));
bind(around);
cbz(len, done);
} else {
andw(len, len, 7);
bind(loop);
ldrd(vtmp2, post(src, 8));
sub(tmp4, tmp4, 1);
zip1(vtmp3, T16B, vtmp2, vtmp1);
st1(vtmp3, T8H, post(dst, 16));
cbnz(tmp4, loop);
}
}
// Do the tail of up to 8 bytes.
add(src, src, len);
ldrd(vtmp3, Address(src, -8));
add(dst, dst, len, ext::uxtw, 1);
zip1(vtmp3, T16B, vtmp3, vtmp1);
strq(vtmp3, Address(dst, -16));
bind(done);
}
// Compress char[] array to byte[].
void MacroAssembler::char_array_compress(Register src, Register dst, Register len,
FloatRegister tmp1Reg, FloatRegister tmp2Reg,
FloatRegister tmp3Reg, FloatRegister tmp4Reg,
Register result) {
encode_iso_array(src, dst, len, result,
tmp1Reg, tmp2Reg, tmp3Reg, tmp4Reg);
cmp(len, zr);
csel(result, result, zr, EQ);
}
// 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));
blr(lr);
if (dst != c_rarg0) {
mov(dst, c_rarg0);
}
pop(saved_regs, sp);
}
void MacroAssembler::cache_wb(Address line) {
assert(line.getMode() == Address::base_plus_offset, "mode should be base_plus_offset");
assert(line.index() == noreg, "index should be noreg");
assert(line.offset() == 0, "offset should be 0");
// would like to assert this
// assert(line._ext.shift == 0, "shift should be zero");
if (VM_Version::supports_dcpop()) {
// writeback using clear virtual address to point of persistence
dc(Assembler::CVAP, line.base());
} else {
// no need to generate anything as Unsafe.writebackMemory should
// never invoke this stub
}
}
void MacroAssembler::cache_wbsync(bool is_pre) {
// we only need a barrier post sync
if (!is_pre) {
membar(Assembler::AnyAny);
}
}