// Copyright (c) 1994-2006 Sun Microsystems Inc.
// All Rights Reserved.
//
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//
// - Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// - Redistribution in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the
// distribution.
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// be used to endorse or promote products derived from this software without
// specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGE.
// The original source code covered by the above license above has been modified
// significantly by Google Inc.
// Copyright 2012 the V8 project authors. All rights reserved.
#ifndef V8_ARM_ASSEMBLER_ARM_INL_H_
#define V8_ARM_ASSEMBLER_ARM_INL_H_
#include "src/arm/assembler-arm.h"
#include "src/assembler.h"
#include "src/debug/debug.h"
#include "src/objects-inl.h"
namespace v8 {
namespace internal {
bool CpuFeatures::SupportsOptimizer() { return true; }
bool CpuFeatures::SupportsWasmSimd128() { return IsSupported(NEON); }
int DoubleRegister::NumRegisters() {
return CpuFeatures::IsSupported(VFP32DREGS) ? 32 : 16;
}
void RelocInfo::apply(intptr_t delta) {
if (RelocInfo::IsInternalReference(rmode_)) {
// absolute code pointer inside code object moves with the code object.
int32_t* p = reinterpret_cast<int32_t*>(pc_);
*p += delta; // relocate entry
} else if (RelocInfo::IsRelativeCodeTarget(rmode_)) {
Instruction* branch = Instruction::At(pc_);
int32_t branch_offset = branch->GetBranchOffset() + delta;
branch->SetBranchOffset(branch_offset);
}
}
Address RelocInfo::target_address() {
DCHECK(IsCodeTargetMode(rmode_) || IsRuntimeEntry(rmode_) ||
IsWasmCall(rmode_));
return Assembler::target_address_at(pc_, constant_pool_);
}
Address RelocInfo::target_address_address() {
DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_) || IsWasmCall(rmode_) ||
IsEmbeddedObject(rmode_) || IsExternalReference(rmode_) ||
IsOffHeapTarget(rmode_));
if (Assembler::IsMovW(Memory<int32_t>(pc_))) {
return pc_;
} else {
DCHECK(Assembler::IsLdrPcImmediateOffset(Memory<int32_t>(pc_)));
return constant_pool_entry_address();
}
}
Address RelocInfo::constant_pool_entry_address() {
DCHECK(IsInConstantPool());
return Assembler::constant_pool_entry_address(pc_, constant_pool_);
}
int RelocInfo::target_address_size() {
return kPointerSize;
}
HeapObject* RelocInfo::target_object() {
DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
return HeapObject::cast(reinterpret_cast<Object*>(
Assembler::target_address_at(pc_, constant_pool_)));
}
Handle<HeapObject> RelocInfo::target_object_handle(Assembler* origin) {
if (IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT) {
return Handle<HeapObject>(reinterpret_cast<HeapObject**>(
Assembler::target_address_at(pc_, constant_pool_)));
}
DCHECK(IsRelativeCodeTarget(rmode_));
return origin->relative_code_target_object_handle_at(pc_);
}
void RelocInfo::set_target_object(Heap* heap, HeapObject* target,
WriteBarrierMode write_barrier_mode,
ICacheFlushMode icache_flush_mode) {
DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
Assembler::set_target_address_at(pc_, constant_pool_,
reinterpret_cast<Address>(target),
icache_flush_mode);
if (write_barrier_mode == UPDATE_WRITE_BARRIER && host() != nullptr) {
WriteBarrierForCode(host(), this, target);
}
}
Address RelocInfo::target_external_reference() {
DCHECK(rmode_ == EXTERNAL_REFERENCE);
return Assembler::target_address_at(pc_, constant_pool_);
}
void RelocInfo::set_target_external_reference(
Address target, ICacheFlushMode icache_flush_mode) {
DCHECK(rmode_ == RelocInfo::EXTERNAL_REFERENCE);
Assembler::set_target_address_at(pc_, constant_pool_, target,
icache_flush_mode);
}
Address RelocInfo::target_internal_reference() {
DCHECK(rmode_ == INTERNAL_REFERENCE);
return Memory<Address>(pc_);
}
Address RelocInfo::target_internal_reference_address() {
DCHECK(rmode_ == INTERNAL_REFERENCE);
return pc_;
}
Address RelocInfo::target_runtime_entry(Assembler* origin) {
DCHECK(IsRuntimeEntry(rmode_));
return target_address();
}
void RelocInfo::set_target_runtime_entry(Address target,
WriteBarrierMode write_barrier_mode,
ICacheFlushMode icache_flush_mode) {
DCHECK(IsRuntimeEntry(rmode_));
if (target_address() != target)
set_target_address(target, write_barrier_mode, icache_flush_mode);
}
Address RelocInfo::target_off_heap_target() {
DCHECK(IsOffHeapTarget(rmode_));
return Assembler::target_address_at(pc_, constant_pool_);
}
void RelocInfo::WipeOut() {
DCHECK(IsEmbeddedObject(rmode_) || IsCodeTarget(rmode_) ||
IsRuntimeEntry(rmode_) || IsExternalReference(rmode_) ||
IsInternalReference(rmode_) || IsOffHeapTarget(rmode_));
if (IsInternalReference(rmode_)) {
Memory<Address>(pc_) = kNullAddress;
} else {
Assembler::set_target_address_at(pc_, constant_pool_, kNullAddress);
}
}
Handle<Code> Assembler::relative_code_target_object_handle_at(
Address pc) const {
Instruction* branch = Instruction::At(pc);
int code_target_index = branch->GetBranchOffset() / kInstrSize;
return GetCodeTarget(code_target_index);
}
template <typename ObjectVisitor>
void RelocInfo::Visit(ObjectVisitor* visitor) {
RelocInfo::Mode mode = rmode();
if (mode == RelocInfo::EMBEDDED_OBJECT) {
visitor->VisitEmbeddedPointer(host(), this);
} else if (RelocInfo::IsCodeTargetMode(mode)) {
visitor->VisitCodeTarget(host(), this);
} else if (mode == RelocInfo::EXTERNAL_REFERENCE) {
visitor->VisitExternalReference(host(), this);
} else if (mode == RelocInfo::INTERNAL_REFERENCE) {
visitor->VisitInternalReference(host(), this);
} else if (RelocInfo::IsRuntimeEntry(mode)) {
visitor->VisitRuntimeEntry(host(), this);
} else if (RelocInfo::IsOffHeapTarget(mode)) {
visitor->VisitOffHeapTarget(host(), this);
}
}
Operand::Operand(int32_t immediate, RelocInfo::Mode rmode) : rmode_(rmode) {
value_.immediate = immediate;
}
Operand Operand::Zero() { return Operand(static_cast<int32_t>(0)); }
Operand::Operand(const ExternalReference& f)
: rmode_(RelocInfo::EXTERNAL_REFERENCE) {
value_.immediate = static_cast<int32_t>(f.address());
}
Operand::Operand(Smi* value) : rmode_(RelocInfo::NONE) {
value_.immediate = reinterpret_cast<intptr_t>(value);
}
Operand::Operand(Register rm) : rm_(rm), shift_op_(LSL), shift_imm_(0) {}
void Assembler::CheckBuffer() {
if (buffer_space() <= kGap) {
GrowBuffer();
}
MaybeCheckConstPool();
}
void Assembler::emit(Instr x) {
CheckBuffer();
*reinterpret_cast<Instr*>(pc_) = x;
pc_ += kInstrSize;
}
Address Assembler::target_address_from_return_address(Address pc) {
// Returns the address of the call target from the return address that will
// be returned to after a call.
// Call sequence on V7 or later is:
// movw ip, #... @ call address low 16
// movt ip, #... @ call address high 16
// blx ip
// @ return address
// For V6 when the constant pool is unavailable, it is:
// mov ip, #... @ call address low 8
// orr ip, ip, #... @ call address 2nd 8
// orr ip, ip, #... @ call address 3rd 8
// orr ip, ip, #... @ call address high 8
// blx ip
// @ return address
// In cases that need frequent patching, the address is in the
// constant pool. It could be a small constant pool load:
// ldr ip, [pc, #...] @ call address
// blx ip
// @ return address
Address candidate = pc - 2 * kInstrSize;
Instr candidate_instr(Memory<int32_t>(candidate));
if (IsLdrPcImmediateOffset(candidate_instr)) {
return candidate;
} else {
if (CpuFeatures::IsSupported(ARMv7)) {
candidate -= 1 * kInstrSize;
DCHECK(IsMovW(Memory<int32_t>(candidate)) &&
IsMovT(Memory<int32_t>(candidate + kInstrSize)));
} else {
candidate -= 3 * kInstrSize;
DCHECK(IsMovImmed(Memory<int32_t>(candidate)) &&
IsOrrImmed(Memory<int32_t>(candidate + kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(candidate + 2 * kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(candidate + 3 * kInstrSize)));
}
return candidate;
}
}
Address Assembler::return_address_from_call_start(Address pc) {
if (IsLdrPcImmediateOffset(Memory<int32_t>(pc))) {
// Load from constant pool, small section.
return pc + kInstrSize * 2;
} else {
if (CpuFeatures::IsSupported(ARMv7)) {
DCHECK(IsMovW(Memory<int32_t>(pc)));
DCHECK(IsMovT(Memory<int32_t>(pc + kInstrSize)));
// A movw / movt load immediate.
return pc + kInstrSize * 3;
} else {
DCHECK(IsMovImmed(Memory<int32_t>(pc)));
DCHECK(IsOrrImmed(Memory<int32_t>(pc + kInstrSize)));
DCHECK(IsOrrImmed(Memory<int32_t>(pc + 2 * kInstrSize)));
DCHECK(IsOrrImmed(Memory<int32_t>(pc + 3 * kInstrSize)));
// A mov / orr load immediate.
return pc + kInstrSize * 5;
}
}
}
void Assembler::deserialization_set_special_target_at(
Address constant_pool_entry, Code* code, Address target) {
Memory<Address>(constant_pool_entry) = target;
}
int Assembler::deserialization_special_target_size(Address location) {
return kSpecialTargetSize;
}
void Assembler::deserialization_set_target_internal_reference_at(
Address pc, Address target, RelocInfo::Mode mode) {
Memory<Address>(pc) = target;
}
bool Assembler::is_constant_pool_load(Address pc) {
return IsLdrPcImmediateOffset(Memory<int32_t>(pc));
}
Address Assembler::constant_pool_entry_address(Address pc,
Address constant_pool) {
DCHECK(Assembler::IsLdrPcImmediateOffset(Memory<int32_t>(pc)));
Instr instr = Memory<int32_t>(pc);
return pc + GetLdrRegisterImmediateOffset(instr) + Instruction::kPcLoadDelta;
}
Address Assembler::target_address_at(Address pc, Address constant_pool) {
if (is_constant_pool_load(pc)) {
// This is a constant pool lookup. Return the value in the constant pool.
return Memory<Address>(constant_pool_entry_address(pc, constant_pool));
} else if (CpuFeatures::IsSupported(ARMv7) && IsMovW(Memory<int32_t>(pc))) {
// This is an movw / movt immediate load. Return the immediate.
DCHECK(IsMovW(Memory<int32_t>(pc)) &&
IsMovT(Memory<int32_t>(pc + kInstrSize)));
Instruction* movw_instr = Instruction::At(pc);
Instruction* movt_instr = Instruction::At(pc + kInstrSize);
return static_cast<Address>((movt_instr->ImmedMovwMovtValue() << 16) |
movw_instr->ImmedMovwMovtValue());
} else if (IsMovImmed(Memory<int32_t>(pc))) {
// This is an mov / orr immediate load. Return the immediate.
DCHECK(IsMovImmed(Memory<int32_t>(pc)) &&
IsOrrImmed(Memory<int32_t>(pc + kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 2 * kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 3 * kInstrSize)));
Instr mov_instr = instr_at(pc);
Instr orr_instr_1 = instr_at(pc + kInstrSize);
Instr orr_instr_2 = instr_at(pc + 2 * kInstrSize);
Instr orr_instr_3 = instr_at(pc + 3 * kInstrSize);
Address ret = static_cast<Address>(
DecodeShiftImm(mov_instr) | DecodeShiftImm(orr_instr_1) |
DecodeShiftImm(orr_instr_2) | DecodeShiftImm(orr_instr_3));
return ret;
} else {
Instruction* branch = Instruction::At(pc);
int32_t delta = branch->GetBranchOffset();
return pc + delta + Instruction::kPcLoadDelta;
}
}
void Assembler::set_target_address_at(Address pc, Address constant_pool,
Address target,
ICacheFlushMode icache_flush_mode) {
if (is_constant_pool_load(pc)) {
// This is a constant pool lookup. Update the entry in the constant pool.
Memory<Address>(constant_pool_entry_address(pc, constant_pool)) = target;
// Intuitively, we would think it is necessary to always flush the
// instruction cache after patching a target address in the code as follows:
// Assembler::FlushICache(pc, sizeof(target));
// However, on ARM, no instruction is actually patched in the case
// of embedded constants of the form:
// ldr ip, [pp, #...]
// since the instruction accessing this address in the constant pool remains
// unchanged.
} else if (CpuFeatures::IsSupported(ARMv7) && IsMovW(Memory<int32_t>(pc))) {
// This is an movw / movt immediate load. Patch the immediate embedded in
// the instructions.
DCHECK(IsMovW(Memory<int32_t>(pc)));
DCHECK(IsMovT(Memory<int32_t>(pc + kInstrSize)));
uint32_t* instr_ptr = reinterpret_cast<uint32_t*>(pc);
uint32_t immediate = static_cast<uint32_t>(target);
instr_ptr[0] = PatchMovwImmediate(instr_ptr[0], immediate & 0xFFFF);
instr_ptr[1] = PatchMovwImmediate(instr_ptr[1], immediate >> 16);
DCHECK(IsMovW(Memory<int32_t>(pc)));
DCHECK(IsMovT(Memory<int32_t>(pc + kInstrSize)));
if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
Assembler::FlushICache(pc, 2 * kInstrSize);
}
} else if (IsMovImmed(Memory<int32_t>(pc))) {
// This is an mov / orr immediate load. Patch the immediate embedded in
// the instructions.
DCHECK(IsMovImmed(Memory<int32_t>(pc)) &&
IsOrrImmed(Memory<int32_t>(pc + kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 2 * kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 3 * kInstrSize)));
uint32_t* instr_ptr = reinterpret_cast<uint32_t*>(pc);
uint32_t immediate = static_cast<uint32_t>(target);
instr_ptr[0] = PatchShiftImm(instr_ptr[0], immediate & kImm8Mask);
instr_ptr[1] = PatchShiftImm(instr_ptr[1], immediate & (kImm8Mask << 8));
instr_ptr[2] = PatchShiftImm(instr_ptr[2], immediate & (kImm8Mask << 16));
instr_ptr[3] = PatchShiftImm(instr_ptr[3], immediate & (kImm8Mask << 24));
DCHECK(IsMovImmed(Memory<int32_t>(pc)) &&
IsOrrImmed(Memory<int32_t>(pc + kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 2 * kInstrSize)) &&
IsOrrImmed(Memory<int32_t>(pc + 3 * kInstrSize)));
if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
Assembler::FlushICache(pc, 4 * kInstrSize);
}
} else {
intptr_t branch_offset = target - pc - Instruction::kPcLoadDelta;
Instruction* branch = Instruction::At(pc);
branch->SetBranchOffset(branch_offset);
if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
Assembler::FlushICache(pc, kInstrSize);
}
}
}
EnsureSpace::EnsureSpace(Assembler* assembler) { assembler->CheckBuffer(); }
template <typename T>
bool UseScratchRegisterScope::CanAcquireVfp() const {
VfpRegList* available = assembler_->GetScratchVfpRegisterList();
DCHECK_NOT_NULL(available);
for (int index = 0; index < T::kNumRegisters; index++) {
T reg = T::from_code(index);
uint64_t mask = reg.ToVfpRegList();
if ((*available & mask) == mask) {
return true;
}
}
return false;
}
template <typename T>
T UseScratchRegisterScope::AcquireVfp() {
VfpRegList* available = assembler_->GetScratchVfpRegisterList();
DCHECK_NOT_NULL(available);
for (int index = 0; index < T::kNumRegisters; index++) {
T reg = T::from_code(index);
uint64_t mask = reg.ToVfpRegList();
if ((*available & mask) == mask) {
*available &= ~mask;
return reg;
}
}
UNREACHABLE();
}
} // namespace internal
} // namespace v8
#endif // V8_ARM_ASSEMBLER_ARM_INL_H_