blob: b72e385d58d9fdd2f4d451d168d931bd6b8076d4 [file] [log] [blame]
// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <limits.h> // For LONG_MIN, LONG_MAX.
#if V8_TARGET_ARCH_ARM
#include "src/base/bits.h"
#include "src/base/division-by-constant.h"
#include "src/base/utils/random-number-generator.h"
#include "src/codegen/assembler-inl.h"
#include "src/codegen/callable.h"
#include "src/codegen/code-factory.h"
#include "src/codegen/external-reference-table.h"
#include "src/codegen/macro-assembler.h"
#include "src/codegen/register-configuration.h"
#include "src/debug/debug.h"
#include "src/execution/frames-inl.h"
#include "src/heap/memory-chunk.h"
#include "src/init/bootstrapper.h"
#include "src/logging/counters.h"
#include "src/numbers/double.h"
#include "src/objects/objects-inl.h"
#include "src/runtime/runtime.h"
#include "src/snapshot/embedded/embedded-data.h"
#include "src/snapshot/snapshot.h"
#include "src/wasm/wasm-code-manager.h"
// Satisfy cpplint check, but don't include platform-specific header. It is
// included recursively via macro-assembler.h.
#if 0
#include "src/codegen/arm/macro-assembler-arm.h"
#endif
namespace v8 {
namespace internal {
int TurboAssembler::RequiredStackSizeForCallerSaved(SaveFPRegsMode fp_mode,
Register exclusion1,
Register exclusion2,
Register exclusion3) const {
int bytes = 0;
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
bytes += NumRegs(list) * kPointerSize;
if (fp_mode == kSaveFPRegs) {
bytes += DwVfpRegister::kNumRegisters * DwVfpRegister::kSizeInBytes;
}
return bytes;
}
int TurboAssembler::PushCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1,
Register exclusion2, Register exclusion3) {
int bytes = 0;
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
stm(db_w, sp, list);
bytes += NumRegs(list) * kPointerSize;
if (fp_mode == kSaveFPRegs) {
SaveFPRegs(sp, lr);
bytes += DwVfpRegister::kNumRegisters * DwVfpRegister::kSizeInBytes;
}
return bytes;
}
int TurboAssembler::PopCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1,
Register exclusion2, Register exclusion3) {
int bytes = 0;
if (fp_mode == kSaveFPRegs) {
RestoreFPRegs(sp, lr);
bytes += DwVfpRegister::kNumRegisters * DwVfpRegister::kSizeInBytes;
}
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
ldm(ia_w, sp, list);
bytes += NumRegs(list) * kPointerSize;
return bytes;
}
void TurboAssembler::LoadFromConstantsTable(Register destination,
int constant_index) {
DCHECK(RootsTable::IsImmortalImmovable(RootIndex::kBuiltinsConstantsTable));
const uint32_t offset =
FixedArray::kHeaderSize + constant_index * kPointerSize - kHeapObjectTag;
LoadRoot(destination, RootIndex::kBuiltinsConstantsTable);
ldr(destination, MemOperand(destination, offset));
}
void TurboAssembler::LoadRootRelative(Register destination, int32_t offset) {
ldr(destination, MemOperand(kRootRegister, offset));
}
void TurboAssembler::LoadRootRegisterOffset(Register destination,
intptr_t offset) {
if (offset == 0) {
Move(destination, kRootRegister);
} else {
add(destination, kRootRegister, Operand(offset));
}
}
void TurboAssembler::Jump(Register target, Condition cond) { bx(target, cond); }
void TurboAssembler::Jump(intptr_t target, RelocInfo::Mode rmode,
Condition cond) {
mov(pc, Operand(target, rmode), LeaveCC, cond);
}
void TurboAssembler::Jump(Address target, RelocInfo::Mode rmode,
Condition cond) {
DCHECK(!RelocInfo::IsCodeTarget(rmode));
Jump(static_cast<intptr_t>(target), rmode, cond);
}
void TurboAssembler::Jump(Handle<Code> code, RelocInfo::Mode rmode,
Condition cond) {
DCHECK(RelocInfo::IsCodeTarget(rmode));
DCHECK_IMPLIES(options().isolate_independent_code,
Builtins::IsIsolateIndependentBuiltin(*code));
DCHECK_IMPLIES(options().use_pc_relative_calls_and_jumps,
Builtins::IsIsolateIndependentBuiltin(*code));
int builtin_index = Builtins::kNoBuiltinId;
bool target_is_builtin =
isolate()->builtins()->IsBuiltinHandle(code, &builtin_index);
if (options().use_pc_relative_calls_and_jumps && target_is_builtin) {
int32_t code_target_index = AddCodeTarget(code);
b(code_target_index * kInstrSize, cond, RelocInfo::RELATIVE_CODE_TARGET);
return;
} else if (root_array_available_ && options().isolate_independent_code) {
// This branch is taken only for specific cctests, where we force isolate
// creation at runtime. At this point, Code space isn't restricted to a
// size s.t. pc-relative calls may be used.
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
int offset = IsolateData::builtin_entry_slot_offset(
static_cast<Builtins::Name>(code->builtin_index()));
ldr(scratch, MemOperand(kRootRegister, offset));
Jump(scratch, cond);
return;
} else if (options().inline_offheap_trampolines && target_is_builtin) {
// Inline the trampoline.
RecordCommentForOffHeapTrampoline(builtin_index);
EmbeddedData d = EmbeddedData::FromBlob();
Address entry = d.InstructionStartOfBuiltin(builtin_index);
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
mov(ip, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Jump(ip, cond);
return;
}
// 'code' is always generated ARM code, never THUMB code
Jump(static_cast<intptr_t>(code.address()), rmode, cond);
}
void TurboAssembler::Jump(const ExternalReference& reference) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Move(scratch, reference);
Jump(scratch);
}
void TurboAssembler::Call(Register target, Condition cond) {
// Block constant pool for the call instruction sequence.
BlockConstPoolScope block_const_pool(this);
blx(target, cond);
}
void TurboAssembler::Call(Address target, RelocInfo::Mode rmode, Condition cond,
TargetAddressStorageMode mode,
bool check_constant_pool) {
// Check if we have to emit the constant pool before we block it.
if (check_constant_pool) MaybeCheckConstPool();
// Block constant pool for the call instruction sequence.
BlockConstPoolScope block_const_pool(this);
bool old_predictable_code_size = predictable_code_size();
if (mode == NEVER_INLINE_TARGET_ADDRESS) {
set_predictable_code_size(true);
}
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
// Call sequence on V7 or later may be :
// movw ip, #... @ call address low 16
// movt ip, #... @ call address high 16
// blx ip
// @ return address
// Or for pre-V7 or values that may be back-patched
// to avoid ICache flushes:
// ldr ip, [pc, #...] @ call address
// blx ip
// @ return address
mov(ip, Operand(target, rmode));
blx(ip, cond);
if (mode == NEVER_INLINE_TARGET_ADDRESS) {
set_predictable_code_size(old_predictable_code_size);
}
}
void TurboAssembler::Call(Handle<Code> code, RelocInfo::Mode rmode,
Condition cond, TargetAddressStorageMode mode,
bool check_constant_pool) {
DCHECK(RelocInfo::IsCodeTarget(rmode));
DCHECK_IMPLIES(options().isolate_independent_code,
Builtins::IsIsolateIndependentBuiltin(*code));
DCHECK_IMPLIES(options().use_pc_relative_calls_and_jumps,
Builtins::IsIsolateIndependentBuiltin(*code));
int builtin_index = Builtins::kNoBuiltinId;
bool target_is_builtin =
isolate()->builtins()->IsBuiltinHandle(code, &builtin_index);
if (target_is_builtin && options().use_pc_relative_calls_and_jumps) {
int32_t code_target_index = AddCodeTarget(code);
bl(code_target_index * kInstrSize, cond, RelocInfo::RELATIVE_CODE_TARGET);
return;
} else if (root_array_available_ && options().isolate_independent_code) {
// This branch is taken only for specific cctests, where we force isolate
// creation at runtime. At this point, Code space isn't restricted to a
// size s.t. pc-relative calls may be used.
int offset = IsolateData::builtin_entry_slot_offset(
static_cast<Builtins::Name>(code->builtin_index()));
ldr(ip, MemOperand(kRootRegister, offset));
Call(ip, cond);
return;
} else if (target_is_builtin && options().inline_offheap_trampolines) {
// Inline the trampoline.
CallBuiltin(builtin_index);
return;
}
// 'code' is always generated ARM code, never THUMB code
DCHECK(code->IsExecutable());
Call(code.address(), rmode, cond, mode);
}
void TurboAssembler::LoadEntryFromBuiltinIndex(Register builtin_index) {
STATIC_ASSERT(kSystemPointerSize == 4);
STATIC_ASSERT(kSmiShiftSize == 0);
STATIC_ASSERT(kSmiTagSize == 1);
STATIC_ASSERT(kSmiTag == 0);
// The builtin_index register contains the builtin index as a Smi.
// Untagging is folded into the indexing operand below.
mov(builtin_index,
Operand(builtin_index, LSL, kSystemPointerSizeLog2 - kSmiTagSize));
add(builtin_index, builtin_index,
Operand(IsolateData::builtin_entry_table_offset()));
ldr(builtin_index, MemOperand(kRootRegister, builtin_index));
}
void TurboAssembler::CallBuiltinByIndex(Register builtin_index) {
LoadEntryFromBuiltinIndex(builtin_index);
Call(builtin_index);
}
void TurboAssembler::CallBuiltin(int builtin_index, Condition cond) {
DCHECK(Builtins::IsBuiltinId(builtin_index));
RecordCommentForOffHeapTrampoline(builtin_index);
EmbeddedData d = EmbeddedData::FromBlob();
Address entry = d.InstructionStartOfBuiltin(builtin_index);
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
mov(ip, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Call(ip, cond);
}
void TurboAssembler::LoadCodeObjectEntry(Register destination,
Register code_object) {
// Code objects are called differently depending on whether we are generating
// builtin code (which will later be embedded into the binary) or compiling
// user JS code at runtime.
// * Builtin code runs in --jitless mode and thus must not call into on-heap
// Code targets. Instead, we dispatch through the builtins entry table.
// * Codegen at runtime does not have this restriction and we can use the
// shorter, branchless instruction sequence. The assumption here is that
// targets are usually generated code and not builtin Code objects.
if (options().isolate_independent_code) {
DCHECK(root_array_available());
Label if_code_is_off_heap, out;
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(!AreAliased(destination, scratch));
DCHECK(!AreAliased(code_object, scratch));
// Check whether the Code object is an off-heap trampoline. If so, call its
// (off-heap) entry point directly without going through the (on-heap)
// trampoline. Otherwise, just call the Code object as always.
ldr(scratch, FieldMemOperand(code_object, Code::kFlagsOffset));
tst(scratch, Operand(Code::IsOffHeapTrampoline::kMask));
b(ne, &if_code_is_off_heap);
// Not an off-heap trampoline, the entry point is at
// Code::raw_instruction_start().
add(destination, code_object, Operand(Code::kHeaderSize - kHeapObjectTag));
jmp(&out);
// An off-heap trampoline, the entry point is loaded from the builtin entry
// table.
bind(&if_code_is_off_heap);
ldr(scratch, FieldMemOperand(code_object, Code::kBuiltinIndexOffset));
lsl(destination, scratch, Operand(kSystemPointerSizeLog2));
add(destination, destination, kRootRegister);
ldr(destination,
MemOperand(destination, IsolateData::builtin_entry_table_offset()));
bind(&out);
} else {
add(destination, code_object, Operand(Code::kHeaderSize - kHeapObjectTag));
}
}
void TurboAssembler::CallCodeObject(Register code_object) {
LoadCodeObjectEntry(code_object, code_object);
Call(code_object);
}
void TurboAssembler::JumpCodeObject(Register code_object) {
LoadCodeObjectEntry(code_object, code_object);
Jump(code_object);
}
void TurboAssembler::StoreReturnAddressAndCall(Register target) {
// This generates the final instruction sequence for calls to C functions
// once an exit frame has been constructed.
//
// Note that this assumes the caller code (i.e. the Code object currently
// being generated) is immovable or that the callee function cannot trigger
// GC, since the callee function will return to it.
// Compute the return address in lr to return to after the jump below. The pc
// is already at '+ 8' from the current instruction; but return is after three
// instructions, so add another 4 to pc to get the return address.
Assembler::BlockConstPoolScope block_const_pool(this);
add(lr, pc, Operand(4));
str(lr, MemOperand(sp));
Call(target);
}
void TurboAssembler::Ret(Condition cond) { bx(lr, cond); }
void TurboAssembler::Drop(int count, Condition cond) {
if (count > 0) {
add(sp, sp, Operand(count * kPointerSize), LeaveCC, cond);
}
}
void TurboAssembler::Drop(Register count, Condition cond) {
add(sp, sp, Operand(count, LSL, kPointerSizeLog2), LeaveCC, cond);
}
void TurboAssembler::Ret(int drop, Condition cond) {
Drop(drop, cond);
Ret(cond);
}
void TurboAssembler::Call(Label* target) { bl(target); }
void TurboAssembler::Push(Handle<HeapObject> handle) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(handle));
push(scratch);
}
void TurboAssembler::Push(Smi smi) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(smi));
push(scratch);
}
void TurboAssembler::PushArray(Register array, Register size, Register scratch,
PushArrayOrder order) {
UseScratchRegisterScope temps(this);
Register counter = scratch;
Register tmp = temps.Acquire();
DCHECK(!AreAliased(array, size, counter, tmp));
Label loop, entry;
if (order == PushArrayOrder::kReverse) {
mov(counter, Operand(0));
b(&entry);
bind(&loop);
ldr(tmp, MemOperand(array, counter, LSL, kSystemPointerSizeLog2));
push(tmp);
add(counter, counter, Operand(1));
bind(&entry);
cmp(counter, size);
b(lt, &loop);
} else {
mov(counter, size);
b(&entry);
bind(&loop);
ldr(tmp, MemOperand(array, counter, LSL, kSystemPointerSizeLog2));
push(tmp);
bind(&entry);
sub(counter, counter, Operand(1), SetCC);
b(ge, &loop);
}
}
void TurboAssembler::Move(Register dst, Smi smi) { mov(dst, Operand(smi)); }
void TurboAssembler::Move(Register dst, Handle<HeapObject> value) {
// TODO(jgruber,v8:8887): Also consider a root-relative load when generating
// non-isolate-independent code. In many cases it might be cheaper than
// embedding the relocatable value.
if (root_array_available_ && options().isolate_independent_code) {
IndirectLoadConstant(dst, value);
return;
}
mov(dst, Operand(value));
}
void TurboAssembler::Move(Register dst, ExternalReference reference) {
// TODO(jgruber,v8:8887): Also consider a root-relative load when generating
// non-isolate-independent code. In many cases it might be cheaper than
// embedding the relocatable value.
if (root_array_available_ && options().isolate_independent_code) {
IndirectLoadExternalReference(dst, reference);
return;
}
mov(dst, Operand(reference));
}
void TurboAssembler::Move(Register dst, Register src, Condition cond) {
if (dst != src) {
mov(dst, src, LeaveCC, cond);
}
}
void TurboAssembler::Move(SwVfpRegister dst, SwVfpRegister src,
Condition cond) {
if (dst != src) {
vmov(dst, src, cond);
}
}
void TurboAssembler::Move(DwVfpRegister dst, DwVfpRegister src,
Condition cond) {
if (dst != src) {
vmov(dst, src, cond);
}
}
void TurboAssembler::Move(QwNeonRegister dst, QwNeonRegister src) {
if (dst != src) {
vmov(dst, src);
}
}
void TurboAssembler::MovePair(Register dst0, Register src0, Register dst1,
Register src1) {
DCHECK_NE(dst0, dst1);
if (dst0 != src1) {
Move(dst0, src0);
Move(dst1, src1);
} else if (dst1 != src0) {
// Swap the order of the moves to resolve the overlap.
Move(dst1, src1);
Move(dst0, src0);
} else {
// Worse case scenario, this is a swap.
Swap(dst0, src0);
}
}
void TurboAssembler::Swap(Register srcdst0, Register srcdst1) {
DCHECK(srcdst0 != srcdst1);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, srcdst0);
mov(srcdst0, srcdst1);
mov(srcdst1, scratch);
}
void TurboAssembler::Swap(DwVfpRegister srcdst0, DwVfpRegister srcdst1) {
DCHECK(srcdst0 != srcdst1);
DCHECK(VfpRegisterIsAvailable(srcdst0));
DCHECK(VfpRegisterIsAvailable(srcdst1));
if (CpuFeatures::IsSupported(NEON)) {
vswp(srcdst0, srcdst1);
} else {
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = temps.AcquireD();
vmov(scratch, srcdst0);
vmov(srcdst0, srcdst1);
vmov(srcdst1, scratch);
}
}
void TurboAssembler::Swap(QwNeonRegister srcdst0, QwNeonRegister srcdst1) {
DCHECK(srcdst0 != srcdst1);
vswp(srcdst0, srcdst1);
}
void MacroAssembler::Mls(Register dst, Register src1, Register src2,
Register srcA, Condition cond) {
if (CpuFeatures::IsSupported(ARMv7)) {
CpuFeatureScope scope(this, ARMv7);
mls(dst, src1, src2, srcA, cond);
} else {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(srcA != scratch);
mul(scratch, src1, src2, LeaveCC, cond);
sub(dst, srcA, scratch, LeaveCC, cond);
}
}
void MacroAssembler::And(Register dst, Register src1, const Operand& src2,
Condition cond) {
if (!src2.IsRegister() && !src2.MustOutputRelocInfo(this) &&
src2.immediate() == 0) {
mov(dst, Operand::Zero(), LeaveCC, cond);
} else if (!(src2.InstructionsRequired(this) == 1) &&
!src2.MustOutputRelocInfo(this) &&
CpuFeatures::IsSupported(ARMv7) &&
base::bits::IsPowerOfTwo(src2.immediate() + 1)) {
CpuFeatureScope scope(this, ARMv7);
ubfx(dst, src1, 0,
base::bits::WhichPowerOfTwo(static_cast<uint32_t>(src2.immediate()) +
1),
cond);
} else {
and_(dst, src1, src2, LeaveCC, cond);
}
}
void MacroAssembler::Ubfx(Register dst, Register src1, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1u << (width + lsb)) - 1u - ((1u << lsb) - 1u);
and_(dst, src1, Operand(mask), LeaveCC, cond);
if (lsb != 0) {
mov(dst, Operand(dst, LSR, lsb), LeaveCC, cond);
}
} else {
CpuFeatureScope scope(this, ARMv7);
ubfx(dst, src1, lsb, width, cond);
}
}
void MacroAssembler::Sbfx(Register dst, Register src1, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
and_(dst, src1, Operand(mask), LeaveCC, cond);
int shift_up = 32 - lsb - width;
int shift_down = lsb + shift_up;
if (shift_up != 0) {
mov(dst, Operand(dst, LSL, shift_up), LeaveCC, cond);
}
if (shift_down != 0) {
mov(dst, Operand(dst, ASR, shift_down), LeaveCC, cond);
}
} else {
CpuFeatureScope scope(this, ARMv7);
sbfx(dst, src1, lsb, width, cond);
}
}
void TurboAssembler::Bfc(Register dst, Register src, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
bic(dst, src, Operand(mask));
} else {
CpuFeatureScope scope(this, ARMv7);
Move(dst, src, cond);
bfc(dst, lsb, width, cond);
}
}
void TurboAssembler::LoadRoot(Register destination, RootIndex index,
Condition cond) {
ldr(destination,
MemOperand(kRootRegister, RootRegisterOffsetForRootIndex(index)), cond);
}
void MacroAssembler::RecordWriteField(Register object, int offset,
Register value,
LinkRegisterStatus lr_status,
SaveFPRegsMode save_fp,
RememberedSetAction remembered_set_action,
SmiCheck smi_check) {
// First, check if a write barrier is even needed. The tests below
// catch stores of Smis.
Label done;
// Skip barrier if writing a smi.
if (smi_check == INLINE_SMI_CHECK) {
JumpIfSmi(value, &done);
}
// Although the object register is tagged, the offset is relative to the start
// of the object, so so offset must be a multiple of kPointerSize.
DCHECK(IsAligned(offset, kPointerSize));
if (emit_debug_code()) {
Label ok;
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
add(scratch, object, Operand(offset - kHeapObjectTag));
tst(scratch, Operand(kPointerSize - 1));
b(eq, &ok);
stop();
bind(&ok);
}
RecordWrite(object, Operand(offset - kHeapObjectTag), value, lr_status,
save_fp, remembered_set_action, OMIT_SMI_CHECK);
bind(&done);
}
void TurboAssembler::SaveRegisters(RegList registers) {
DCHECK_GT(NumRegs(registers), 0);
RegList regs = 0;
for (int i = 0; i < Register::kNumRegisters; ++i) {
if ((registers >> i) & 1u) {
regs |= Register::from_code(i).bit();
}
}
stm(db_w, sp, regs);
}
void TurboAssembler::RestoreRegisters(RegList registers) {
DCHECK_GT(NumRegs(registers), 0);
RegList regs = 0;
for (int i = 0; i < Register::kNumRegisters; ++i) {
if ((registers >> i) & 1u) {
regs |= Register::from_code(i).bit();
}
}
ldm(ia_w, sp, regs);
}
void TurboAssembler::CallEphemeronKeyBarrier(Register object, Operand offset,
SaveFPRegsMode fp_mode) {
EphemeronKeyBarrierDescriptor descriptor;
RegList registers = descriptor.allocatable_registers();
SaveRegisters(registers);
Register object_parameter(
descriptor.GetRegisterParameter(EphemeronKeyBarrierDescriptor::kObject));
Register slot_parameter(descriptor.GetRegisterParameter(
EphemeronKeyBarrierDescriptor::kSlotAddress));
Register fp_mode_parameter(
descriptor.GetRegisterParameter(EphemeronKeyBarrierDescriptor::kFPMode));
MoveObjectAndSlot(object_parameter, slot_parameter, object, offset);
Move(fp_mode_parameter, Smi::FromEnum(fp_mode));
Call(isolate()->builtins()->builtin_handle(Builtins::kEphemeronKeyBarrier),
RelocInfo::CODE_TARGET);
RestoreRegisters(registers);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Operand offset, RememberedSetAction remembered_set_action,
SaveFPRegsMode fp_mode) {
CallRecordWriteStub(
object, offset, remembered_set_action, fp_mode,
isolate()->builtins()->builtin_handle(Builtins::kRecordWrite),
kNullAddress);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Operand offset, RememberedSetAction remembered_set_action,
SaveFPRegsMode fp_mode, Address wasm_target) {
CallRecordWriteStub(object, offset, remembered_set_action, fp_mode,
Handle<Code>::null(), wasm_target);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Operand offset, RememberedSetAction remembered_set_action,
SaveFPRegsMode fp_mode, Handle<Code> code_target, Address wasm_target) {
DCHECK_NE(code_target.is_null(), wasm_target == kNullAddress);
// TODO(albertnetymk): For now we ignore remembered_set_action and fp_mode,
// i.e. always emit remember set and save FP registers in RecordWriteStub. If
// large performance regression is observed, we should use these values to
// avoid unnecessary work.
RecordWriteDescriptor descriptor;
RegList registers = descriptor.allocatable_registers();
SaveRegisters(registers);
Register object_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kObject));
Register slot_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kSlot));
Register remembered_set_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kRememberedSet));
Register fp_mode_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kFPMode));
MoveObjectAndSlot(object_parameter, slot_parameter, object, offset);
Move(remembered_set_parameter, Smi::FromEnum(remembered_set_action));
Move(fp_mode_parameter, Smi::FromEnum(fp_mode));
if (code_target.is_null()) {
Call(wasm_target, RelocInfo::WASM_STUB_CALL);
} else {
Call(code_target, RelocInfo::CODE_TARGET);
}
RestoreRegisters(registers);
}
void TurboAssembler::MoveObjectAndSlot(Register dst_object, Register dst_slot,
Register object, Operand offset) {
DCHECK_NE(dst_object, dst_slot);
DCHECK(offset.IsRegister() || offset.IsImmediate());
// If `offset` is a register, it cannot overlap with `object`.
DCHECK_IMPLIES(offset.IsRegister(), offset.rm() != object);
// If the slot register does not overlap with the object register, we can
// overwrite it.
if (dst_slot != object) {
add(dst_slot, object, offset);
Move(dst_object, object);
return;
}
DCHECK_EQ(dst_slot, object);
// If the destination object register does not overlap with the offset
// register, we can overwrite it.
if (!offset.IsRegister() || (offset.rm() != dst_object)) {
Move(dst_object, dst_slot);
add(dst_slot, dst_slot, offset);
return;
}
DCHECK_EQ(dst_object, offset.rm());
// We only have `dst_slot` and `dst_object` left as distinct registers so we
// have to swap them. We write this as a add+sub sequence to avoid using a
// scratch register.
add(dst_slot, dst_slot, dst_object);
sub(dst_object, dst_slot, dst_object);
}
// The register 'object' contains a heap object pointer. The heap object tag is
// shifted away. A scratch register also needs to be available.
void MacroAssembler::RecordWrite(Register object, Operand offset,
Register value, LinkRegisterStatus lr_status,
SaveFPRegsMode fp_mode,
RememberedSetAction remembered_set_action,
SmiCheck smi_check) {
DCHECK_NE(object, value);
if (emit_debug_code()) {
{
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
add(scratch, object, offset);
ldr(scratch, MemOperand(scratch));
cmp(scratch, value);
}
Check(eq, AbortReason::kWrongAddressOrValuePassedToRecordWrite);
}
if ((remembered_set_action == OMIT_REMEMBERED_SET &&
!FLAG_incremental_marking) ||
FLAG_disable_write_barriers) {
return;
}
// First, check if a write barrier is even needed. The tests below
// catch stores of smis and stores into the young generation.
Label done;
if (smi_check == INLINE_SMI_CHECK) {
JumpIfSmi(value, &done);
}
CheckPageFlag(value, MemoryChunk::kPointersToHereAreInterestingMask, eq,
&done);
CheckPageFlag(object, MemoryChunk::kPointersFromHereAreInterestingMask, eq,
&done);
// Record the actual write.
if (lr_status == kLRHasNotBeenSaved) {
push(lr);
}
CallRecordWriteStub(object, offset, remembered_set_action, fp_mode);
if (lr_status == kLRHasNotBeenSaved) {
pop(lr);
}
bind(&done);
}
void TurboAssembler::PushCommonFrame(Register marker_reg) {
if (marker_reg.is_valid()) {
if (marker_reg.code() > fp.code()) {
stm(db_w, sp, fp.bit() | lr.bit());
mov(fp, Operand(sp));
Push(marker_reg);
} else {
stm(db_w, sp, marker_reg.bit() | fp.bit() | lr.bit());
add(fp, sp, Operand(kPointerSize));
}
} else {
stm(db_w, sp, fp.bit() | lr.bit());
mov(fp, sp);
}
}
void TurboAssembler::PushStandardFrame(Register function_reg) {
DCHECK(!function_reg.is_valid() || function_reg.code() < cp.code());
stm(db_w, sp,
(function_reg.is_valid() ? function_reg.bit() : 0) | cp.bit() | fp.bit() |
lr.bit());
int offset = -StandardFrameConstants::kContextOffset;
offset += function_reg.is_valid() ? kPointerSize : 0;
add(fp, sp, Operand(offset));
Push(kJavaScriptCallArgCountRegister);
}
void TurboAssembler::VFPCanonicalizeNaN(const DwVfpRegister dst,
const DwVfpRegister src,
const Condition cond) {
// Subtracting 0.0 preserves all inputs except for signalling NaNs, which
// become quiet NaNs. We use vsub rather than vadd because vsub preserves -0.0
// inputs: -0.0 + 0.0 = 0.0, but -0.0 - 0.0 = -0.0.
vsub(dst, src, kDoubleRegZero, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const SwVfpRegister src1,
const SwVfpRegister src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const SwVfpRegister src1,
const float src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const DwVfpRegister src1,
const DwVfpRegister src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const DwVfpRegister src1,
const double src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const SwVfpRegister src1,
const SwVfpRegister src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const SwVfpRegister src1,
const float src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const DwVfpRegister src1,
const DwVfpRegister src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const DwVfpRegister src1,
const double src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VmovHigh(Register dst, DwVfpRegister src) {
if (src.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(src.code());
vmov(dst, loc.high());
} else {
vmov(NeonS32, dst, src, 1);
}
}
void TurboAssembler::VmovHigh(DwVfpRegister dst, Register src) {
if (dst.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(dst.code());
vmov(loc.high(), src);
} else {
vmov(NeonS32, dst, 1, src);
}
}
void TurboAssembler::VmovLow(Register dst, DwVfpRegister src) {
if (src.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(src.code());
vmov(dst, loc.low());
} else {
vmov(NeonS32, dst, src, 0);
}
}
void TurboAssembler::VmovLow(DwVfpRegister dst, Register src) {
if (dst.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(dst.code());
vmov(loc.low(), src);
} else {
vmov(NeonS32, dst, 0, src);
}
}
void TurboAssembler::VmovExtended(Register dst, int src_code) {
DCHECK_LE(SwVfpRegister::kNumRegisters, src_code);
DCHECK_GT(SwVfpRegister::kNumRegisters * 2, src_code);
if (src_code & 0x1) {
VmovHigh(dst, DwVfpRegister::from_code(src_code / 2));
} else {
VmovLow(dst, DwVfpRegister::from_code(src_code / 2));
}
}
void TurboAssembler::VmovExtended(int dst_code, Register src) {
DCHECK_LE(SwVfpRegister::kNumRegisters, dst_code);
DCHECK_GT(SwVfpRegister::kNumRegisters * 2, dst_code);
if (dst_code & 0x1) {
VmovHigh(DwVfpRegister::from_code(dst_code / 2), src);
} else {
VmovLow(DwVfpRegister::from_code(dst_code / 2), src);
}
}
void TurboAssembler::VmovExtended(int dst_code, int src_code) {
if (src_code == dst_code) return;
if (src_code < SwVfpRegister::kNumRegisters &&
dst_code < SwVfpRegister::kNumRegisters) {
// src and dst are both s-registers.
vmov(SwVfpRegister::from_code(dst_code),
SwVfpRegister::from_code(src_code));
return;
}
DwVfpRegister dst_d_reg = DwVfpRegister::from_code(dst_code / 2);
DwVfpRegister src_d_reg = DwVfpRegister::from_code(src_code / 2);
int dst_offset = dst_code & 1;
int src_offset = src_code & 1;
if (CpuFeatures::IsSupported(NEON)) {
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = temps.AcquireD();
// On Neon we can shift and insert from d-registers.
if (src_offset == dst_offset) {
// Offsets are the same, use vdup to copy the source to the opposite lane.
vdup(Neon32, scratch, src_d_reg, src_offset);
// Here we are extending the lifetime of scratch.
src_d_reg = scratch;
src_offset = dst_offset ^ 1;
}
if (dst_offset) {
if (dst_d_reg == src_d_reg) {
vdup(Neon32, dst_d_reg, src_d_reg, 0);
} else {
vsli(Neon64, dst_d_reg, src_d_reg, 32);
}
} else {
if (dst_d_reg == src_d_reg) {
vdup(Neon32, dst_d_reg, src_d_reg, 1);
} else {
vsri(Neon64, dst_d_reg, src_d_reg, 32);
}
}
return;
}
// Without Neon, use the scratch registers to move src and/or dst into
// s-registers.
UseScratchRegisterScope temps(this);
LowDwVfpRegister d_scratch = temps.AcquireLowD();
LowDwVfpRegister d_scratch2 = temps.AcquireLowD();
int s_scratch_code = d_scratch.low().code();
int s_scratch_code2 = d_scratch2.low().code();
if (src_code < SwVfpRegister::kNumRegisters) {
// src is an s-register, dst is not.
vmov(d_scratch, dst_d_reg);
vmov(SwVfpRegister::from_code(s_scratch_code + dst_offset),
SwVfpRegister::from_code(src_code));
vmov(dst_d_reg, d_scratch);
} else if (dst_code < SwVfpRegister::kNumRegisters) {
// dst is an s-register, src is not.
vmov(d_scratch, src_d_reg);
vmov(SwVfpRegister::from_code(dst_code),
SwVfpRegister::from_code(s_scratch_code + src_offset));
} else {
// Neither src or dst are s-registers. Both scratch double registers are
// available when there are 32 VFP registers.
vmov(d_scratch, src_d_reg);
vmov(d_scratch2, dst_d_reg);
vmov(SwVfpRegister::from_code(s_scratch_code + dst_offset),
SwVfpRegister::from_code(s_scratch_code2 + src_offset));
vmov(dst_d_reg, d_scratch2);
}
}
void TurboAssembler::VmovExtended(int dst_code, const MemOperand& src) {
if (dst_code < SwVfpRegister::kNumRegisters) {
vldr(SwVfpRegister::from_code(dst_code), src);
} else {
UseScratchRegisterScope temps(this);
LowDwVfpRegister scratch = temps.AcquireLowD();
// TODO(bbudge) If Neon supported, use load single lane form of vld1.
int dst_s_code = scratch.low().code() + (dst_code & 1);
vmov(scratch, DwVfpRegister::from_code(dst_code / 2));
vldr(SwVfpRegister::from_code(dst_s_code), src);
vmov(DwVfpRegister::from_code(dst_code / 2), scratch);
}
}
void TurboAssembler::VmovExtended(const MemOperand& dst, int src_code) {
if (src_code < SwVfpRegister::kNumRegisters) {
vstr(SwVfpRegister::from_code(src_code), dst);
} else {
// TODO(bbudge) If Neon supported, use store single lane form of vst1.
UseScratchRegisterScope temps(this);
LowDwVfpRegister scratch = temps.AcquireLowD();
int src_s_code = scratch.low().code() + (src_code & 1);
vmov(scratch, DwVfpRegister::from_code(src_code / 2));
vstr(SwVfpRegister::from_code(src_s_code), dst);
}
}
void TurboAssembler::ExtractLane(Register dst, QwNeonRegister src,
NeonDataType dt, int lane) {
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_word = byte >> kDoubleSizeLog2;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
DwVfpRegister double_source =
DwVfpRegister::from_code(src.code() * 2 + double_word);
vmov(dt, dst, double_source, double_lane);
}
void TurboAssembler::ExtractLane(Register dst, DwVfpRegister src,
NeonDataType dt, int lane) {
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
vmov(dt, dst, src, double_lane);
}
void TurboAssembler::ExtractLane(SwVfpRegister dst, QwNeonRegister src,
int lane) {
int s_code = src.code() * 4 + lane;
VmovExtended(dst.code(), s_code);
}
void TurboAssembler::ExtractLane(DwVfpRegister dst, QwNeonRegister src,
int lane) {
DwVfpRegister double_dst = DwVfpRegister::from_code(src.code() * 2 + lane);
vmov(dst, double_dst);
}
void TurboAssembler::ReplaceLane(QwNeonRegister dst, QwNeonRegister src,
Register src_lane, NeonDataType dt, int lane) {
Move(dst, src);
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_word = byte >> kDoubleSizeLog2;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
DwVfpRegister double_dst =
DwVfpRegister::from_code(dst.code() * 2 + double_word);
vmov(dt, double_dst, double_lane, src_lane);
}
void TurboAssembler::ReplaceLane(QwNeonRegister dst, QwNeonRegister src,
SwVfpRegister src_lane, int lane) {
Move(dst, src);
int s_code = dst.code() * 4 + lane;
VmovExtended(s_code, src_lane.code());
}
void TurboAssembler::ReplaceLane(QwNeonRegister dst, QwNeonRegister src,
DwVfpRegister src_lane, int lane) {
Move(dst, src);
DwVfpRegister double_dst = DwVfpRegister::from_code(dst.code() * 2 + lane);
vmov(double_dst, src_lane);
}
void TurboAssembler::LslPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_high, src_low));
DCHECK(!AreAliased(dst_high, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
lsl(dst_high, src_low, Operand(scratch));
mov(dst_low, Operand(0));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsl(dst_high, src_high, Operand(shift));
orr(dst_high, dst_high, Operand(src_low, LSR, scratch));
lsl(dst_low, src_low, Operand(shift));
bind(&done);
}
void TurboAssembler::LslPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK_GE(63, shift);
DCHECK(!AreAliased(dst_high, src_low));
if (shift == 0) {
Move(dst_high, src_high);
Move(dst_low, src_low);
} else if (shift == 32) {
Move(dst_high, src_low);
Move(dst_low, Operand(0));
} else if (shift >= 32) {
shift &= 0x1F;
lsl(dst_high, src_low, Operand(shift));
mov(dst_low, Operand(0));
} else {
lsl(dst_high, src_high, Operand(shift));
orr(dst_high, dst_high, Operand(src_low, LSR, 32 - shift));
lsl(dst_low, src_low, Operand(shift));
}
}
void TurboAssembler::LsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_low, src_high));
DCHECK(!AreAliased(dst_low, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
lsr(dst_low, src_high, Operand(scratch));
mov(dst_high, Operand(0));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, scratch));
lsr(dst_high, src_high, Operand(shift));
bind(&done);
}
void TurboAssembler::LsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK_GE(63, shift);
DCHECK(!AreAliased(dst_low, src_high));
if (shift == 32) {
mov(dst_low, src_high);
mov(dst_high, Operand(0));
} else if (shift > 32) {
shift &= 0x1F;
lsr(dst_low, src_high, Operand(shift));
mov(dst_high, Operand(0));
} else if (shift == 0) {
Move(dst_low, src_low);
Move(dst_high, src_high);
} else {
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, 32 - shift));
lsr(dst_high, src_high, Operand(shift));
}
}
void TurboAssembler::AsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_low, src_high));
DCHECK(!AreAliased(dst_low, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
asr(dst_low, src_high, Operand(scratch));
asr(dst_high, src_high, Operand(31));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, scratch));
asr(dst_high, src_high, Operand(shift));
bind(&done);
}
void TurboAssembler::AsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK_GE(63, shift);
DCHECK(!AreAliased(dst_low, src_high));
if (shift == 32) {
mov(dst_low, src_high);
asr(dst_high, src_high, Operand(31));
} else if (shift > 32) {
shift &= 0x1F;
asr(dst_low, src_high, Operand(shift));
asr(dst_high, src_high, Operand(31));
} else if (shift == 0) {
Move(dst_low, src_low);
Move(dst_high, src_high);
} else {
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, 32 - shift));
asr(dst_high, src_high, Operand(shift));
}
}
void TurboAssembler::StubPrologue(StackFrame::Type type) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(StackFrame::TypeToMarker(type)));
PushCommonFrame(scratch);
}
void TurboAssembler::Prologue() { PushStandardFrame(r1); }
void TurboAssembler::EnterFrame(StackFrame::Type type,
bool load_constant_pool_pointer_reg) {
// r0-r3: preserved
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(StackFrame::TypeToMarker(type)));
PushCommonFrame(scratch);
}
int TurboAssembler::LeaveFrame(StackFrame::Type type) {
// r0: preserved
// r1: preserved
// r2: preserved
// Drop the execution stack down to the frame pointer and restore
// the caller frame pointer and return address.
mov(sp, fp);
int frame_ends = pc_offset();
ldm(ia_w, sp, fp.bit() | lr.bit());
return frame_ends;
}
#ifdef V8_OS_WIN
void TurboAssembler::AllocateStackSpace(Register bytes_scratch) {
// "Functions that allocate 4 KB or more on the stack must ensure that each
// page prior to the final page is touched in order." Source:
// https://docs.microsoft.com/en-us/cpp/build/overview-of-arm-abi-conventions?view=vs-2019#stack
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = temps.AcquireD();
Label check_offset;
Label touch_next_page;
jmp(&check_offset);
bind(&touch_next_page);
sub(sp, sp, Operand(kStackPageSize));
// Just to touch the page, before we increment further.
vldr(scratch, MemOperand(sp));
sub(bytes_scratch, bytes_scratch, Operand(kStackPageSize));
bind(&check_offset);
cmp(bytes_scratch, Operand(kStackPageSize));
b(gt, &touch_next_page);
sub(sp, sp, bytes_scratch);
}
void TurboAssembler::AllocateStackSpace(int bytes) {
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = no_dreg;
while (bytes > kStackPageSize) {
if (scratch == no_dreg) {
scratch = temps.AcquireD();
}
sub(sp, sp, Operand(kStackPageSize));
vldr(scratch, MemOperand(sp));
bytes -= kStackPageSize;
}
sub(sp, sp, Operand(bytes));
}
#endif
void MacroAssembler::EnterExitFrame(bool save_doubles, int stack_space,
StackFrame::Type frame_type) {
DCHECK(frame_type == StackFrame::EXIT ||
frame_type == StackFrame::BUILTIN_EXIT);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
// Set up the frame structure on the stack.
DCHECK_EQ(2 * kPointerSize, ExitFrameConstants::kCallerSPDisplacement);
DCHECK_EQ(1 * kPointerSize, ExitFrameConstants::kCallerPCOffset);
DCHECK_EQ(0 * kPointerSize, ExitFrameConstants::kCallerFPOffset);
mov(scratch, Operand(StackFrame::TypeToMarker(frame_type)));
PushCommonFrame(scratch);
// Reserve room for saved entry sp.
sub(sp, fp, Operand(ExitFrameConstants::kFixedFrameSizeFromFp));
if (emit_debug_code()) {
mov(scratch, Operand::Zero());
str(scratch, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
// Save the frame pointer and the context in top.
Move(scratch, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
str(fp, MemOperand(scratch));
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
str(cp, MemOperand(scratch));
// Optionally save all double registers.
if (save_doubles) {
SaveFPRegs(sp, scratch);
// Note that d0 will be accessible at
// fp - ExitFrameConstants::kFrameSize -
// DwVfpRegister::kNumRegisters * kDoubleSize,
// since the sp slot and code slot were pushed after the fp.
}
// Reserve place for the return address and stack space and align the frame
// preparing for calling the runtime function.
const int frame_alignment = MacroAssembler::ActivationFrameAlignment();
AllocateStackSpace((stack_space + 1) * kPointerSize);
if (frame_alignment > 0) {
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
and_(sp, sp, Operand(-frame_alignment));
}
// Set the exit frame sp value to point just before the return address
// location.
add(scratch, sp, Operand(kPointerSize));
str(scratch, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
int TurboAssembler::ActivationFrameAlignment() {
#if V8_HOST_ARCH_ARM
// Running on the real platform. Use the alignment as mandated by the local
// environment.
// Note: This will break if we ever start generating snapshots on one ARM
// platform for another ARM platform with a different alignment.
return base::OS::ActivationFrameAlignment();
#else // V8_HOST_ARCH_ARM
// If we are using the simulator then we should always align to the expected
// alignment. As the simulator is used to generate snapshots we do not know
// if the target platform will need alignment, so this is controlled from a
// flag.
return FLAG_sim_stack_alignment;
#endif // V8_HOST_ARCH_ARM
}
void MacroAssembler::LeaveExitFrame(bool save_doubles, Register argument_count,
bool argument_count_is_length) {
ConstantPoolUnavailableScope constant_pool_unavailable(this);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
// Optionally restore all double registers.
if (save_doubles) {
// Calculate the stack location of the saved doubles and restore them.
const int offset = ExitFrameConstants::kFixedFrameSizeFromFp;
sub(r3, fp, Operand(offset + DwVfpRegister::kNumRegisters * kDoubleSize));
RestoreFPRegs(r3, scratch);
}
// Clear top frame.
mov(r3, Operand::Zero());
Move(scratch, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
str(r3, MemOperand(scratch));
// Restore current context from top and clear it in debug mode.
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
ldr(cp, MemOperand(scratch));
#ifdef DEBUG
mov(r3, Operand(Context::kInvalidContext));
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
str(r3, MemOperand(scratch));
#endif
// Tear down the exit frame, pop the arguments, and return.
mov(sp, Operand(fp));
ldm(ia_w, sp, fp.bit() | lr.bit());
if (argument_count.is_valid()) {
if (argument_count_is_length) {
add(sp, sp, argument_count);
} else {
add(sp, sp, Operand(argument_count, LSL, kPointerSizeLog2));
}
}
}
void TurboAssembler::MovFromFloatResult(const DwVfpRegister dst) {
if (use_eabi_hardfloat()) {
Move(dst, d0);
} else {
vmov(dst, r0, r1);
}
}
// On ARM this is just a synonym to make the purpose clear.
void TurboAssembler::MovFromFloatParameter(DwVfpRegister dst) {
MovFromFloatResult(dst);
}
void TurboAssembler::PrepareForTailCall(Register callee_args_count,
Register caller_args_count,
Register scratch0, Register scratch1) {
DCHECK(!AreAliased(callee_args_count, caller_args_count, scratch0, scratch1));
// Calculate the end of destination area where we will put the arguments
// after we drop current frame. We add kPointerSize to count the receiver
// argument which is not included into formal parameters count.
Register dst_reg = scratch0;
add(dst_reg, fp, Operand(caller_args_count, LSL, kPointerSizeLog2));
add(dst_reg, dst_reg,
Operand(StandardFrameConstants::kCallerSPOffset + kPointerSize));
Register src_reg = caller_args_count;
// Calculate the end of source area. +kPointerSize is for the receiver.
add(src_reg, sp, Operand(callee_args_count, LSL, kPointerSizeLog2));
add(src_reg, src_reg, Operand(kPointerSize));
if (FLAG_debug_code) {
cmp(src_reg, dst_reg);
Check(lo, AbortReason::kStackAccessBelowStackPointer);
}
// Restore caller's frame pointer and return address now as they will be
// overwritten by the copying loop.
ldr(lr, MemOperand(fp, StandardFrameConstants::kCallerPCOffset));
ldr(fp, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
// Now copy callee arguments to the caller frame going backwards to avoid
// callee arguments corruption (source and destination areas could overlap).
// Both src_reg and dst_reg are pointing to the word after the one to copy,
// so they must be pre-decremented in the loop.
Register tmp_reg = scratch1;
Label loop, entry;
b(&entry);
bind(&loop);
ldr(tmp_reg, MemOperand(src_reg, -kPointerSize, PreIndex));
str(tmp_reg, MemOperand(dst_reg, -kPointerSize, PreIndex));
bind(&entry);
cmp(sp, src_reg);
b(ne, &loop);
// Leave current frame.
mov(sp, dst_reg);
}
void MacroAssembler::LoadStackLimit(Register destination, StackLimitKind kind) {
DCHECK(root_array_available());
Isolate* isolate = this->isolate();
ExternalReference limit =
kind == StackLimitKind::kRealStackLimit
? ExternalReference::address_of_real_jslimit(isolate)
: ExternalReference::address_of_jslimit(isolate);
DCHECK(TurboAssembler::IsAddressableThroughRootRegister(isolate, limit));
intptr_t offset =
TurboAssembler::RootRegisterOffsetForExternalReference(isolate, limit);
CHECK(is_int32(offset));
ldr(destination, MemOperand(kRootRegister, offset));
}
void MacroAssembler::StackOverflowCheck(Register num_args, Register scratch,
Label* stack_overflow) {
// Check the stack for overflow. We are not trying to catch
// interruptions (e.g. debug break and preemption) here, so the "real stack
// limit" is checked.
LoadStackLimit(scratch, StackLimitKind::kRealStackLimit);
// Make scratch the space we have left. The stack might already be overflowed
// here which will cause scratch to become negative.
sub(scratch, sp, scratch);
// Check if the arguments will overflow the stack.
cmp(scratch, Operand(num_args, LSL, kPointerSizeLog2));
b(le, stack_overflow); // Signed comparison.
}
void MacroAssembler::InvokePrologue(Register expected_parameter_count,
Register actual_parameter_count,
Label* done, InvokeFlag flag) {
Label regular_invoke;
// r0: actual arguments count
// r1: function (passed through to callee)
// r2: expected arguments count
DCHECK_EQ(actual_parameter_count, r0);
DCHECK_EQ(expected_parameter_count, r2);
#ifdef V8_NO_ARGUMENTS_ADAPTOR
// If the expected parameter count is equal to the adaptor sentinel, no need
// to push undefined value as arguments.
cmp(expected_parameter_count, Operand(kDontAdaptArgumentsSentinel));
b(eq, &regular_invoke);
// If overapplication or if the actual argument count is equal to the
// formal parameter count, no need to push extra undefined values.
sub(expected_parameter_count, expected_parameter_count,
actual_parameter_count, SetCC);
b(le, &regular_invoke);
Label stack_overflow;
Register scratch = r4;
StackOverflowCheck(expected_parameter_count, scratch, &stack_overflow);
// Underapplication. Move the arguments already in the stack, including the
// receiver and the return address.
{
Label copy, check;
Register num = r5, src = r6, dest = r9; // r7 and r8 are context and root.
mov(src, sp);
// Update stack pointer.
lsl(scratch, expected_parameter_count, Operand(kSystemPointerSizeLog2));
AllocateStackSpace(scratch);
mov(dest, sp);
mov(num, actual_parameter_count);
b(&check);
bind(&copy);
ldr(scratch, MemOperand(src, kSystemPointerSize, PostIndex));
str(scratch, MemOperand(dest, kSystemPointerSize, PostIndex));
sub(num, num, Operand(1), SetCC);
bind(&check);
b(ge, &copy);
}
// Fill remaining expected arguments with undefined values.
LoadRoot(scratch, RootIndex::kUndefinedValue);
{
Label loop;
bind(&loop);
str(scratch, MemOperand(r9, kSystemPointerSize, PostIndex));
sub(expected_parameter_count, expected_parameter_count, Operand(1), SetCC);
b(gt, &loop);
}
b(&regular_invoke);
bind(&stack_overflow);
{
FrameScope frame(this,
has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
CallRuntime(Runtime::kThrowStackOverflow);
bkpt(0);
}
#else
// Check whether the expected and actual arguments count match. If not,
// setup registers according to contract with ArgumentsAdaptorTrampoline.
cmp(expected_parameter_count, actual_parameter_count);
b(eq, &regular_invoke);
Handle<Code> adaptor = BUILTIN_CODE(isolate(), ArgumentsAdaptorTrampoline);
if (flag == CALL_FUNCTION) {
Call(adaptor);
b(done);
} else {
Jump(adaptor, RelocInfo::CODE_TARGET);
}
#endif
bind(&regular_invoke);
}
void MacroAssembler::CallDebugOnFunctionCall(Register fun, Register new_target,
Register expected_parameter_count,
Register actual_parameter_count) {
// Load receiver to pass it later to DebugOnFunctionCall hook.
ldr(r4, ReceiverOperand(actual_parameter_count));
FrameScope frame(this, has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
SmiTag(expected_parameter_count);
Push(expected_parameter_count);
SmiTag(actual_parameter_count);
Push(actual_parameter_count);
if (new_target.is_valid()) {
Push(new_target);
}
Push(fun);
Push(fun);
Push(r4);
CallRuntime(Runtime::kDebugOnFunctionCall);
Pop(fun);
if (new_target.is_valid()) {
Pop(new_target);
}
Pop(actual_parameter_count);
SmiUntag(actual_parameter_count);
Pop(expected_parameter_count);
SmiUntag(expected_parameter_count);
}
void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
Register expected_parameter_count,
Register actual_parameter_count,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK_IMPLIES(flag == CALL_FUNCTION, has_frame());
DCHECK_EQ(function, r1);
DCHECK_IMPLIES(new_target.is_valid(), new_target == r3);
// On function call, call into the debugger if necessary.
Label debug_hook, continue_after_hook;
{
ExternalReference debug_hook_active =
ExternalReference::debug_hook_on_function_call_address(isolate());
Move(r4, debug_hook_active);
ldrsb(r4, MemOperand(r4));
cmp(r4, Operand(0));
b(ne, &debug_hook);
}
bind(&continue_after_hook);
// Clear the new.target register if not given.
if (!new_target.is_valid()) {
LoadRoot(r3, RootIndex::kUndefinedValue);
}
Label done;
InvokePrologue(expected_parameter_count, actual_parameter_count, &done, flag);
// We call indirectly through the code field in the function to
// allow recompilation to take effect without changing any of the
// call sites.
Register code = kJavaScriptCallCodeStartRegister;
ldr(code, FieldMemOperand(function, JSFunction::kCodeOffset));
if (flag == CALL_FUNCTION) {
CallCodeObject(code);
} else {
DCHECK(flag == JUMP_FUNCTION);
JumpCodeObject(code);
}
b(&done);
// Deferred debug hook.
bind(&debug_hook);
CallDebugOnFunctionCall(function, new_target, expected_parameter_count,
actual_parameter_count);
b(&continue_after_hook);
// Continue here if InvokePrologue does handle the invocation due to
// mismatched parameter counts.
bind(&done);
}
void MacroAssembler::InvokeFunctionWithNewTarget(
Register fun, Register new_target, Register actual_parameter_count,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK_IMPLIES(flag == CALL_FUNCTION, has_frame());
// Contract with called JS functions requires that function is passed in r1.
DCHECK_EQ(fun, r1);
Register expected_reg = r2;
Register temp_reg = r4;
ldr(temp_reg, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
ldrh(expected_reg,
FieldMemOperand(temp_reg,
SharedFunctionInfo::kFormalParameterCountOffset));
InvokeFunctionCode(fun, new_target, expected_reg, actual_parameter_count,
flag);
}
void MacroAssembler::InvokeFunction(Register function,
Register expected_parameter_count,
Register actual_parameter_count,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK_IMPLIES(flag == CALL_FUNCTION, has_frame());
// Contract with called JS functions requires that function is passed in r1.
DCHECK_EQ(function, r1);
// Get the function and setup the context.
ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
InvokeFunctionCode(r1, no_reg, expected_parameter_count,
actual_parameter_count, flag);
}
void MacroAssembler::MaybeDropFrames() {
// Check whether we need to drop frames to restart a function on the stack.
ExternalReference restart_fp =
ExternalReference::debug_restart_fp_address(isolate());
Move(r1, restart_fp);
ldr(r1, MemOperand(r1));
tst(r1, r1);
Jump(BUILTIN_CODE(isolate(), FrameDropperTrampoline), RelocInfo::CODE_TARGET,
ne);
}
void MacroAssembler::PushStackHandler() {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 2 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
Push(Smi::zero()); // Padding.
// Link the current handler as the next handler.
Move(r6,
ExternalReference::Create(IsolateAddressId::kHandlerAddress, isolate()));
ldr(r5, MemOperand(r6));
push(r5);
// Set this new handler as the current one.
str(sp, MemOperand(r6));
}
void MacroAssembler::PopStackHandler() {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
pop(r1);
Move(scratch,
ExternalReference::Create(IsolateAddressId::kHandlerAddress, isolate()));
str(r1, MemOperand(scratch));
add(sp, sp, Operand(StackHandlerConstants::kSize - kPointerSize));
}
void MacroAssembler::CompareObjectType(Register object, Register map,
Register type_reg, InstanceType type) {
UseScratchRegisterScope temps(this);
const Register temp = type_reg == no_reg ? temps.Acquire() : type_reg;
LoadMap(map, object);
CompareInstanceType(map, temp, type);
}
void MacroAssembler::CompareInstanceType(Register map, Register type_reg,
InstanceType type) {
ldrh(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
cmp(type_reg, Operand(type));
}
void MacroAssembler::CompareRoot(Register obj, RootIndex index) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(obj != scratch);
LoadRoot(scratch, index);
cmp(obj, scratch);
}
void MacroAssembler::JumpIfIsInRange(Register value, unsigned lower_limit,
unsigned higher_limit,
Label* on_in_range) {
if (lower_limit != 0) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
sub(scratch, value, Operand(lower_limit));
cmp(scratch, Operand(higher_limit - lower_limit));
} else {
cmp(value, Operand(higher_limit));
}
b(ls, on_in_range);
}
void TurboAssembler::TryInlineTruncateDoubleToI(Register result,
DwVfpRegister double_input,
Label* done) {
UseScratchRegisterScope temps(this);
SwVfpRegister single_scratch = SwVfpRegister::no_reg();
if (temps.CanAcquireVfp<SwVfpRegister>()) {
single_scratch = temps.AcquireS();
} else {
// Re-use the input as a scratch register. However, we can only do this if
// the input register is d0-d15 as there are no s32+ registers.
DCHECK_LT(double_input.code(), LowDwVfpRegister::kNumRegisters);
LowDwVfpRegister double_scratch =
LowDwVfpRegister::from_code(double_input.code());
single_scratch = double_scratch.low();
}
vcvt_s32_f64(single_scratch, double_input);
vmov(result, single_scratch);
Register scratch = temps.Acquire();
// If result is not saturated (0x7FFFFFFF or 0x80000000), we are done.
sub(scratch, result, Operand(1));
cmp(scratch, Operand(0x7FFFFFFE));
b(lt, done);
}
void TurboAssembler::TruncateDoubleToI(Isolate* isolate, Zone* zone,
Register result,
DwVfpRegister double_input,
StubCallMode stub_mode) {
Label done;
TryInlineTruncateDoubleToI(result, double_input, &done);
// If we fell through then inline version didn't succeed - call stub instead.
push(lr);
AllocateStackSpace(kDoubleSize); // Put input on stack.
vstr(double_input, MemOperand(sp, 0));
if (stub_mode == StubCallMode::kCallWasmRuntimeStub) {
Call(wasm::WasmCode::kDoubleToI, RelocInfo::WASM_STUB_CALL);
} else if (options().inline_offheap_trampolines) {
CallBuiltin(Builtins::kDoubleToI);
} else {
Call(BUILTIN_CODE(isolate, DoubleToI), RelocInfo::CODE_TARGET);
}
ldr(result, MemOperand(sp, 0));
add(sp, sp, Operand(kDoubleSize));
pop(lr);
bind(&done);
}
void MacroAssembler::CallRuntime(const Runtime::Function* f, int num_arguments,
SaveFPRegsMode save_doubles) {
// All parameters are on the stack. r0 has the return value after call.
// If the expected number of arguments of the runtime function is
// constant, we check that the actual number of arguments match the
// expectation.
CHECK(f->nargs < 0 || f->nargs == num_arguments);
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
mov(r0, Operand(num_arguments));
Move(r1, ExternalReference::Create(f));
Handle<Code> code =
CodeFactory::CEntry(isolate(), f->result_size, save_doubles);
Call(code, RelocInfo::CODE_TARGET);
}
void MacroAssembler::TailCallRuntime(Runtime::FunctionId fid) {
const Runtime::Function* function = Runtime::FunctionForId(fid);
DCHECK_EQ(1, function->result_size);
if (function->nargs >= 0) {
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
mov(r0, Operand(function->nargs));
}
JumpToExternalReference(ExternalReference::Create(fid));
}
void MacroAssembler::JumpToExternalReference(const ExternalReference& builtin,
bool builtin_exit_frame) {
#if defined(__thumb__)
// Thumb mode builtin.
DCHECK_EQ(builtin.address() & 1, 1);
#endif
Move(r1, builtin);
Handle<Code> code = CodeFactory::CEntry(isolate(), 1, kDontSaveFPRegs,
kArgvOnStack, builtin_exit_frame);
Jump(code, RelocInfo::CODE_TARGET);
}
void MacroAssembler::JumpToInstructionStream(Address entry) {
mov(kOffHeapTrampolineRegister, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Jump(kOffHeapTrampolineRegister);
}
void MacroAssembler::LoadWeakValue(Register out, Register in,
Label* target_if_cleared) {
cmp(in, Operand(kClearedWeakHeapObjectLower32));
b(eq, target_if_cleared);
and_(out, in, Operand(~kWeakHeapObjectMask));
}
void MacroAssembler::IncrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
DCHECK_GT(value, 0);
if (FLAG_native_code_counters && counter->Enabled()) {
Move(scratch2, ExternalReference::Create(counter));
ldr(scratch1, MemOperand(scratch2));
add(scratch1, scratch1, Operand(value));
str(scratch1, MemOperand(scratch2));
}
}
void MacroAssembler::DecrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
DCHECK_GT(value, 0);
if (FLAG_native_code_counters && counter->Enabled()) {
Move(scratch2, ExternalReference::Create(counter));
ldr(scratch1, MemOperand(scratch2));
sub(scratch1, scratch1, Operand(value));
str(scratch1, MemOperand(scratch2));
}
}
void TurboAssembler::Assert(Condition cond, AbortReason reason) {
if (emit_debug_code()) Check(cond, reason);
}
void TurboAssembler::AssertUnreachable(AbortReason reason) {
if (emit_debug_code()) Abort(reason);
}
void TurboAssembler::Check(Condition cond, AbortReason reason) {
Label L;
b(cond, &L);
Abort(reason);
// will not return here
bind(&L);
}
void TurboAssembler::Abort(AbortReason reason) {
Label abort_start;
bind(&abort_start);
#ifdef DEBUG
const char* msg = GetAbortReason(reason);
RecordComment("Abort message: ");
RecordComment(msg);
#endif
// Avoid emitting call to builtin if requested.
if (trap_on_abort()) {
stop();
return;
}
if (should_abort_hard()) {
// We don't care if we constructed a frame. Just pretend we did.
FrameScope assume_frame(this, StackFrame::NONE);
Move32BitImmediate(r0, Operand(static_cast<int>(reason)));
PrepareCallCFunction(1, 0, r1);
Move(r1, ExternalReference::abort_with_reason());
// Use Call directly to avoid any unneeded overhead. The function won't
// return anyway.
Call(r1);
return;
}
Move(r1, Smi::FromInt(static_cast<int>(reason)));
// Disable stub call restrictions to always allow calls to abort.
if (!has_frame()) {
// We don't actually want to generate a pile of code for this, so just
// claim there is a stack frame, without generating one.
FrameScope scope(this, StackFrame::NONE);
Call(BUILTIN_CODE(isolate(), Abort), RelocInfo::CODE_TARGET);
} else {
Call(BUILTIN_CODE(isolate(), Abort), RelocInfo::CODE_TARGET);
}
// will not return here
}
void MacroAssembler::LoadMap(Register destination, Register object) {
ldr(destination, FieldMemOperand(object, HeapObject::kMapOffset));
}
void MacroAssembler::LoadGlobalProxy(Register dst) {
LoadNativeContextSlot(Context::GLOBAL_PROXY_INDEX, dst);
}
void MacroAssembler::LoadNativeContextSlot(int index, Register dst) {
LoadMap(dst, cp);
ldr(dst, FieldMemOperand(
dst, Map::kConstructorOrBackPointerOrNativeContextOffset));
ldr(dst, MemOperand(dst, Context::SlotOffset(index)));
}
void TurboAssembler::InitializeRootRegister() {
ExternalReference isolate_root = ExternalReference::isolate_root(isolate());
mov(kRootRegister, Operand(isolate_root));
}
void MacroAssembler::SmiTag(Register reg, SBit s) {
add(reg, reg, Operand(reg), s);
}
void MacroAssembler::SmiTag(Register dst, Register src, SBit s) {
add(dst, src, Operand(src), s);
}
void MacroAssembler::SmiTst(Register value) {
tst(value, Operand(kSmiTagMask));
}
void TurboAssembler::JumpIfSmi(Register value, Label* smi_label) {
tst(value, Operand(kSmiTagMask));
b(eq, smi_label);
}
void TurboAssembler::JumpIfEqual(Register x, int32_t y, Label* dest) {
cmp(x, Operand(y));
b(eq, dest);
}
void TurboAssembler::JumpIfLessThan(Register x, int32_t y, Label* dest) {
cmp(x, Operand(y));
b(lt, dest);
}
void MacroAssembler::JumpIfNotSmi(Register value, Label* not_smi_label) {
tst(value, Operand(kSmiTagMask));
b(ne, not_smi_label);
}
void MacroAssembler::AssertNotSmi(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmi);
}
}
void MacroAssembler::AssertSmi(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(eq, AbortReason::kOperandIsNotASmi);
}
}
void MacroAssembler::AssertConstructor(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAConstructor);
push(object);
LoadMap(object, object);
ldrb(object, FieldMemOperand(object, Map::kBitFieldOffset));
tst(object, Operand(Map::Bits1::IsConstructorBit::kMask));
pop(object);
Check(ne, AbortReason::kOperandIsNotAConstructor);
}
}
void MacroAssembler::AssertFunction(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAFunction);
push(object);
CompareObjectType(object, object, object, JS_FUNCTION_TYPE);
pop(object);
Check(eq, AbortReason::kOperandIsNotAFunction);
}
}
void MacroAssembler::AssertBoundFunction(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotABoundFunction);
push(object);
CompareObjectType(object, object, object, JS_BOUND_FUNCTION_TYPE);
pop(object);
Check(eq, AbortReason::kOperandIsNotABoundFunction);
}
}
void MacroAssembler::AssertGeneratorObject(Register object) {
if (!emit_debug_code()) return;
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAGeneratorObject);
// Load map
Register map = object;
push(object);
LoadMap(map, object);
// Check if JSGeneratorObject
Label do_check;
Register instance_type = object;
CompareInstanceType(map, instance_type, JS_GENERATOR_OBJECT_TYPE);
b(eq, &do_check);
// Check if JSAsyncFunctionObject (See MacroAssembler::CompareInstanceType)
cmp(instance_type, Operand(JS_ASYNC_FUNCTION_OBJECT_TYPE));
b(eq, &do_check);
// Check if JSAsyncGeneratorObject (See MacroAssembler::CompareInstanceType)
cmp(instance_type, Operand(JS_ASYNC_GENERATOR_OBJECT_TYPE));
bind(&do_check);
// Restore generator object to register and perform assertion
pop(object);
Check(eq, AbortReason::kOperandIsNotAGeneratorObject);
}
void MacroAssembler::AssertUndefinedOrAllocationSite(Register object,
Register scratch) {
if (emit_debug_code()) {
Label done_checking;
AssertNotSmi(object);
CompareRoot(object, RootIndex::kUndefinedValue);
b(eq, &done_checking);
LoadMap(scratch, object);
CompareInstanceType(scratch, scratch, ALLOCATION_SITE_TYPE);
Assert(eq, AbortReason::kExpectedUndefinedOrCell);
bind(&done_checking);
}
}
void TurboAssembler::CheckFor32DRegs(Register scratch) {
Move(scratch, ExternalReference::cpu_features());
ldr(scratch, MemOperand(scratch));
tst(scratch, Operand(1u << VFP32DREGS));
}
void TurboAssembler::SaveFPRegs(Register location, Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vstm(db_w, location, d16, d31, ne);
sub(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
vstm(db_w, location, d0, d15);
}
void TurboAssembler::RestoreFPRegs(Register location, Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vldm(ia_w, location, d0, d15);
vldm(ia_w, location, d16, d31, ne);
add(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
}
void TurboAssembler::SaveFPRegsToHeap(Register location, Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vstm(ia_w, location, d0, d15);
vstm(ia_w, location, d16, d31, ne);
add(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
}
void TurboAssembler::RestoreFPRegsFromHeap(Register location,
Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vldm(ia_w, location, d0, d15);
vldm(ia_w, location, d16, d31, ne);
add(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
}
template <typename T>
void TurboAssembler::FloatMaxHelper(T result, T left, T right,
Label* out_of_line) {
// This trivial case is caught sooner, so that the out-of-line code can be
// completely avoided.
DCHECK(left != right);
if (CpuFeatures::IsSupported(ARMv8)) {
CpuFeatureScope scope(this, ARMv8);
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
vmaxnm(result, left, right);
} else {
Label done;
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
// Avoid a conditional instruction if the result register is unique.
bool aliased_result_reg = result == left || result == right;
Move(result, right, aliased_result_reg ? mi : al);
Move(result, left, gt);
b(ne, &done);
// Left and right are equal, but check for +/-0.
VFPCompareAndSetFlags(left, 0.0);
b(eq, out_of_line);
// The arguments are equal and not zero, so it doesn't matter which input we
// pick. We have already moved one input into the result (if it didn't
// already alias) so there's nothing more to do.
bind(&done);
}
}
template <typename T>
void TurboAssembler::FloatMaxOutOfLineHelper(T result, T left, T right) {
DCHECK(left != right);
// ARMv8: At least one of left and right is a NaN.
// Anything else: At least one of left and right is a NaN, or both left and
// right are zeroes with unknown sign.
// If left and right are +/-0, select the one with the most positive sign.
// If left or right are NaN, vadd propagates the appropriate one.
vadd(result, left, right);
}
template <typename T>
void TurboAssembler::FloatMinHelper(T result, T left, T right,
Label* out_of_line) {
// This trivial case is caught sooner, so that the out-of-line code can be
// completely avoided.
DCHECK(left != right);
if (CpuFeatures::IsSupported(ARMv8)) {
CpuFeatureScope scope(this, ARMv8);
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
vminnm(result, left, right);
} else {
Label done;
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
// Avoid a conditional instruction if the result register is unique.
bool aliased_result_reg = result == left || result == right;
Move(result, left, aliased_result_reg ? mi : al);
Move(result, right, gt);
b(ne, &done);
// Left and right are equal, but check for +/-0.
VFPCompareAndSetFlags(left, 0.0);
// If the arguments are equal and not zero, it doesn't matter which input we
// pick. We have already moved one input into the result (if it didn't
// already alias) so there's nothing more to do.
b(ne, &done);
// At this point, both left and right are either 0 or -0.
// We could use a single 'vorr' instruction here if we had NEON support.
// The algorithm used is -((-L) + (-R)), which is most efficiently expressed
// as -((-L) - R).
if (left == result) {
DCHECK(right != result);
vneg(result, left);
vsub(result, result, right);
vneg(result, result);
} else {
DCHECK(left != result);
vneg(result, right);
vsub(result, result, left);
vneg(result, result);
}
bind(&done);
}
}
template <typename T>
void TurboAssembler::FloatMinOutOfLineHelper(T result, T left, T right) {
DCHECK(left != right);
// At least one of left and right is a NaN. Use vadd to propagate the NaN
// appropriately. +/-0 is handled inline.
vadd(result, left, right);
}
void TurboAssembler::FloatMax(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right, Label* out_of_line) {
FloatMaxHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMin(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right, Label* out_of_line) {
FloatMinHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMax(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right, Label* out_of_line) {
FloatMaxHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMin(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right, Label* out_of_line) {
FloatMinHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMaxOutOfLine(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right) {
FloatMaxOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMinOutOfLine(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right) {
FloatMinOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMaxOutOfLine(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right) {
FloatMaxOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMinOutOfLine(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right) {
FloatMinOutOfLineHelper(result, left, right);
}
static const int kRegisterPassedArguments = 4;
// The hardfloat calling convention passes double arguments in registers d0-d7.
static const int kDoubleRegisterPassedArguments = 8;
int TurboAssembler::CalculateStackPassedWords(int num_reg_arguments,
int num_double_arguments) {
int stack_passed_words = 0;
if (use_eabi_hardfloat()) {
// In the hard floating point calling convention, we can use the first 8
// registers to pass doubles.
if (num_double_arguments > kDoubleRegisterPassedArguments) {
stack_passed_words +=
2 * (num_double_arguments - kDoubleRegisterPassedArguments);
}
} else {
// In the soft floating point calling convention, every double
// argument is passed using two registers.
num_reg_arguments += 2 * num_double_arguments;
}
// Up to four simple arguments are passed in registers r0..r3.
if (num_reg_arguments > kRegisterPassedArguments) {
stack_passed_words += num_reg_arguments - kRegisterPassedArguments;
}
return stack_passed_words;
}
void TurboAssembler::PrepareCallCFunction(int num_reg_arguments,
int num_double_arguments,
Register scratch) {
int frame_alignment = ActivationFrameAlignment();
int stack_passed_arguments =
CalculateStackPassedWords(num_reg_arguments, num_double_arguments);
if (frame_alignment > kPointerSize) {
UseScratchRegisterScope temps(this);
if (!scratch.is_valid()) scratch = temps.Acquire();
// Make stack end at alignment and make room for num_arguments - 4 words
// and the original value of sp.
mov(scratch, sp);
AllocateStackSpace((stack_passed_arguments + 1) * kPointerSize);
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
and_(sp, sp, Operand(-frame_alignment));
str(scratch, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else if (stack_passed_arguments > 0) {
AllocateStackSpace(stack_passed_arguments * kPointerSize);
}
}
void TurboAssembler::MovToFloatParameter(DwVfpRegister src) {
DCHECK(src == d0);
if (!use_eabi_hardfloat()) {
vmov(r0, r1, src);
}
}
// On ARM this is just a synonym to make the purpose clear.
void TurboAssembler::MovToFloatResult(DwVfpRegister src) {
MovToFloatParameter(src);
}
void TurboAssembler::MovToFloatParameters(DwVfpRegister src1,
DwVfpRegister src2) {
DCHECK(src1 == d0);
DCHECK(src2 == d1);
if (!use_eabi_hardfloat()) {
vmov(r0, r1, src1);
vmov(r2, r3, src2);
}
}
void TurboAssembler::CallCFunction(ExternalReference function,
int num_reg_arguments,
int num_double_arguments) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Move(scratch, function);
CallCFunctionHelper(scratch, num_reg_arguments, num_double_arguments);
}
void TurboAssembler::CallCFunction(Register function, int num_reg_arguments,
int num_double_arguments) {
CallCFunctionHelper(function, num_reg_arguments, num_double_arguments);
}
void TurboAssembler::CallCFunction(ExternalReference function,
int num_arguments) {
CallCFunction(function, num_arguments, 0);
}
void TurboAssembler::CallCFunction(Register function, int num_arguments) {
CallCFunction(function, num_arguments, 0);
}
void TurboAssembler::CallCFunctionHelper(Register function,
int num_reg_arguments,
int num_double_arguments) {
DCHECK_LE(num_reg_arguments + num_double_arguments, kMaxCParameters);
DCHECK(has_frame());
// Make sure that the stack is aligned before calling a C function unless
// running in the simulator. The simulator has its own alignment check which
// provides more information.
#if V8_HOST_ARCH_ARM
if (emit_debug_code()) {
int frame_alignment = base::OS::ActivationFrameAlignment();
int frame_alignment_mask = frame_alignment - 1;
if (frame_alignment > kPointerSize) {
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
Label alignment_as_expected;
tst(sp, Operand(frame_alignment_mask));
b(eq, &alignment_as_expected);
// Don't use Check here, as it will call Runtime_Abort possibly
// re-entering here.
stop();
bind(&alignment_as_expected);
}
}
#endif
// Save the frame pointer and PC so that the stack layout remains iterable,
// even without an ExitFrame which normally exists between JS and C frames.
Register addr_scratch = r4;
// See x64 code for reasoning about how to address the isolate data fields.
if (root_array_available()) {
str(pc,
MemOperand(kRootRegister, IsolateData::fast_c_call_caller_pc_offset()));
str(fp,
MemOperand(kRootRegister, IsolateData::fast_c_call_caller_fp_offset()));
} else {
DCHECK_NOT_NULL(isolate());
Push(addr_scratch);
Move(addr_scratch,
ExternalReference::fast_c_call_caller_pc_address(isolate()));
str(pc, MemOperand(addr_scratch));
Move(addr_scratch,
ExternalReference::fast_c_call_caller_fp_address(isolate()));
str(fp, MemOperand(addr_scratch));
Pop(addr_scratch);
}
// Just call directly. The function called cannot cause a GC, or
// allow preemption, so the return address in the link register
// stays correct.
Call(function);
// We don't unset the PC; the FP is the source of truth.
Register zero_scratch = r5;
Push(zero_scratch);
mov(zero_scratch, Operand::Zero());
if (root_array_available()) {
str(zero_scratch,
MemOperand(kRootRegister, IsolateData::fast_c_call_caller_fp_offset()));
} else {
DCHECK_NOT_NULL(isolate());
Push(addr_scratch);
Move(addr_scratch,
ExternalReference::fast_c_call_caller_fp_address(isolate()));
str(zero_scratch, MemOperand(addr_scratch));
Pop(addr_scratch);
}
Pop(zero_scratch);
int stack_passed_arguments =
CalculateStackPassedWords(num_reg_arguments, num_double_arguments);
if (ActivationFrameAlignment() > kPointerSize) {
ldr(sp, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else {
add(sp, sp, Operand(stack_passed_arguments * kPointerSize));
}
}
void TurboAssembler::CheckPageFlag(Register object, int mask, Condition cc,
Label* condition_met) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(cc == eq || cc == ne);
Bfc(scratch, object, 0, kPageSizeBits);
ldr(scratch, MemOperand(scratch, BasicMemoryChunk::kFlagsOffset));
tst(scratch, Operand(mask));
b(cc, condition_met);
}
Register GetRegisterThatIsNotOneOf(Register reg1, Register reg2, Register reg3,
Register reg4, Register reg5,
Register reg6) {
RegList regs = 0;
if (reg1.is_valid()) regs |= reg1.bit();
if (reg2.is_valid()) regs |= reg2.bit();
if (reg3.is_valid()) regs |= reg3.bit();
if (reg4.is_valid()) regs |= reg4.bit();
if (reg5.is_valid()) regs |= reg5.bit();
if (reg6.is_valid()) regs |= reg6.bit();
const RegisterConfiguration* config = RegisterConfiguration::Default();
for (int i = 0; i < config->num_allocatable_general_registers(); ++i) {
int code = config->GetAllocatableGeneralCode(i);
Register candidate = Register::from_code(code);
if (regs & candidate.bit()) continue;
return candidate;
}
UNREACHABLE();
}
void TurboAssembler::ComputeCodeStartAddress(Register dst) {
// We can use the register pc - 8 for the address of the current instruction.
sub(dst, pc, Operand(pc_offset() + Instruction::kPcLoadDelta));
}
void TurboAssembler::ResetSpeculationPoisonRegister() {
mov(kSpeculationPoisonRegister, Operand(-1));
}
void TurboAssembler::CallForDeoptimization(Builtins::Name target, int,
Label* exit, DeoptimizeKind kind,
Label*) {
BlockConstPoolScope block_const_pool(this);
ldr(ip, MemOperand(kRootRegister,
IsolateData::builtin_entry_slot_offset(target)));
Call(ip);
DCHECK_EQ(SizeOfCodeGeneratedSince(exit),
(kind == DeoptimizeKind::kLazy)
? Deoptimizer::kLazyDeoptExitSize
: Deoptimizer::kNonLazyDeoptExitSize);
USE(exit, kind);
}
void TurboAssembler::Trap() { stop(); }
void TurboAssembler::DebugBreak() { stop(); }
} // namespace internal
} // namespace v8
#endif // V8_TARGET_ARCH_ARM