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DEFINITIONS
This source file includes following definitions.
- CpuFeaturesImpliedByCompiler
- Probe
- ToNumber
- ToRegister
- IsCodedSpecially
- PatchCode
- PatchCodeWithCall
- emit_debug_code_
- GetCode
- Align
- CodeTargetAlign
- GetRtReg
- GetRsReg
- GetRdReg
- GetRt
- GetRtField
- GetRs
- GetRsField
- GetRd
- GetRdField
- GetSa
- GetSaField
- GetOpcodeField
- GetFunction
- GetFunctionField
- GetImmediate16
- GetLabelConst
- IsPop
- IsPush
- IsSwRegFpOffset
- IsLwRegFpOffset
- IsSwRegFpNegOffset
- IsLwRegFpNegOffset
- IsBranch
- IsBeq
- IsBne
- IsJump
- IsJ
- IsJal
- IsJr
- IsJalr
- IsLui
- IsOri
- IsNop
- GetBranchOffset
- IsLw
- GetLwOffset
- SetLwOffset
- IsSw
- SetSwOffset
- IsAddImmediate
- SetAddImmediateOffset
- IsAndImmediate
- target_at
- target_at_put
- print
- bind_to
- bind
- next
- is_near
- MustUseReg
- GenInstrRegister
- GenInstrRegister
- GenInstrRegister
- GenInstrRegister
- GenInstrRegister
- GenInstrImmediate
- GenInstrImmediate
- GenInstrImmediate
- GenInstrJump
- get_trampoline_entry
- jump_address
- branch_offset
- label_at_put
- bal
- beq
- bgez
- bgezal
- bgtz
- blez
- bltz
- bltzal
- bne
- j
- jr
- jal
- jalr
- j_or_jr
- jal_or_jalr
- addu
- addiu
- subu
- mul
- mult
- multu
- div
- divu
- and_
- andi
- or_
- ori
- xor_
- xori
- nor
- sll
- sllv
- srl
- srlv
- sra
- srav
- rotr
- rotrv
- LoadRegPlusOffsetToAt
- lb
- lbu
- lh
- lhu
- lw
- lwl
- lwr
- sb
- sh
- sw
- swl
- swr
- lui
- break_
- stop
- tge
- tgeu
- tlt
- tltu
- teq
- tne
- mfhi
- mflo
- slt
- sltu
- slti
- sltiu
- movz
- movn
- movt
- movf
- clz
- ins_
- ext_
- lwc1
- ldc1
- swc1
- sdc1
- mtc1
- mfc1
- ctc1
- cfc1
- DoubleAsTwoUInt32
- add_d
- sub_d
- mul_d
- div_d
- abs_d
- mov_d
- neg_d
- sqrt_d
- cvt_w_s
- cvt_w_d
- trunc_w_s
- trunc_w_d
- round_w_s
- round_w_d
- floor_w_s
- floor_w_d
- ceil_w_s
- ceil_w_d
- cvt_l_s
- cvt_l_d
- trunc_l_s
- trunc_l_d
- round_l_s
- round_l_d
- floor_l_s
- floor_l_d
- ceil_l_s
- ceil_l_d
- cvt_s_w
- cvt_s_l
- cvt_s_d
- cvt_d_w
- cvt_d_l
- cvt_d_s
- c
- fcmp
- bc1f
- bc1t
- RecordJSReturn
- RecordDebugBreakSlot
- RecordComment
- RelocateInternalReference
- GrowBuffer
- db
- dd
- RecordRelocInfo
- BlockTrampolinePoolFor
- CheckTrampolinePool
- target_address_at
- QuietNaN
- set_target_address_at
- JumpLabelToJumpRegister
// Copyright (c) 1994-2006 Sun Microsystems Inc.
// All Rights Reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// - 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.
//
// - Neither the name of Sun Microsystems or the names of contributors may
// 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.
#include "v8.h"
#if defined(V8_TARGET_ARCH_MIPS)
#include "mips/assembler-mips-inl.h"
#include "serialize.h"
namespace v8 {
namespace internal {
#ifdef DEBUG
bool CpuFeatures::initialized_ = false;
#endif
unsigned CpuFeatures::supported_ = 0;
unsigned CpuFeatures::found_by_runtime_probing_ = 0;
// Get the CPU features enabled by the build. For cross compilation the
// preprocessor symbols CAN_USE_FPU_INSTRUCTIONS
// can be defined to enable FPU instructions when building the
// snapshot.
static uint64_t CpuFeaturesImpliedByCompiler() {
uint64_t answer = 0;
#ifdef CAN_USE_FPU_INSTRUCTIONS
answer |= 1u << FPU;
#endif // def CAN_USE_FPU_INSTRUCTIONS
#ifdef __mips__
// If the compiler is allowed to use FPU then we can use FPU too in our code
// generation even when generating snapshots. This won't work for cross
// compilation.
#if(defined(__mips_hard_float) && __mips_hard_float != 0)
answer |= 1u << FPU;
#endif // defined(__mips_hard_float) && __mips_hard_float != 0
#endif // def __mips__
return answer;
}
void CpuFeatures::Probe() {
unsigned standard_features = (OS::CpuFeaturesImpliedByPlatform() |
CpuFeaturesImpliedByCompiler());
ASSERT(supported_ == 0 || supported_ == standard_features);
#ifdef DEBUG
initialized_ = true;
#endif
// Get the features implied by the OS and the compiler settings. This is the
// minimal set of features which is also allowed for generated code in the
// snapshot.
supported_ |= standard_features;
if (Serializer::enabled()) {
// No probing for features if we might serialize (generate snapshot).
return;
}
// If the compiler is allowed to use fpu then we can use fpu too in our
// code generation.
#if !defined(__mips__)
// For the simulator=mips build, use FPU when FLAG_enable_fpu is enabled.
if (FLAG_enable_fpu) {
supported_ |= 1u << FPU;
}
#else
// Probe for additional features not already known to be available.
if (OS::MipsCpuHasFeature(FPU)) {
// This implementation also sets the FPU flags if
// runtime detection of FPU returns true.
supported_ |= 1u << FPU;
found_by_runtime_probing_ |= 1u << FPU;
}
#endif
}
int ToNumber(Register reg) {
ASSERT(reg.is_valid());
const int kNumbers[] = {
0, // zero_reg
1, // at
2, // v0
3, // v1
4, // a0
5, // a1
6, // a2
7, // a3
8, // t0
9, // t1
10, // t2
11, // t3
12, // t4
13, // t5
14, // t6
15, // t7
16, // s0
17, // s1
18, // s2
19, // s3
20, // s4
21, // s5
22, // s6
23, // s7
24, // t8
25, // t9
26, // k0
27, // k1
28, // gp
29, // sp
30, // fp
31, // ra
};
return kNumbers[reg.code()];
}
Register ToRegister(int num) {
ASSERT(num >= 0 && num < kNumRegisters);
const Register kRegisters[] = {
zero_reg,
at,
v0, v1,
a0, a1, a2, a3,
t0, t1, t2, t3, t4, t5, t6, t7,
s0, s1, s2, s3, s4, s5, s6, s7,
t8, t9,
k0, k1,
gp,
sp,
fp,
ra
};
return kRegisters[num];
}
// -----------------------------------------------------------------------------
// Implementation of RelocInfo.
const int RelocInfo::kApplyMask = RelocInfo::kCodeTargetMask |
1 << RelocInfo::INTERNAL_REFERENCE;
bool RelocInfo::IsCodedSpecially() {
// The deserializer needs to know whether a pointer is specially coded. Being
// specially coded on MIPS means that it is a lui/ori instruction, and that is
// always the case inside code objects.
return true;
}
// Patch the code at the current address with the supplied instructions.
void RelocInfo::PatchCode(byte* instructions, int instruction_count) {
Instr* pc = reinterpret_cast<Instr*>(pc_);
Instr* instr = reinterpret_cast<Instr*>(instructions);
for (int i = 0; i < instruction_count; i++) {
*(pc + i) = *(instr + i);
}
// Indicate that code has changed.
CPU::FlushICache(pc_, instruction_count * Assembler::kInstrSize);
}
// Patch the code at the current PC with a call to the target address.
// Additional guard instructions can be added if required.
void RelocInfo::PatchCodeWithCall(Address target, int guard_bytes) {
// Patch the code at the current address with a call to the target.
UNIMPLEMENTED_MIPS();
}
// -----------------------------------------------------------------------------
// Implementation of Operand and MemOperand.
// See assembler-mips-inl.h for inlined constructors.
Operand::Operand(Handle<Object> handle) {
rm_ = no_reg;
// Verify all Objects referred by code are NOT in new space.
Object* obj = *handle;
ASSERT(!HEAP->InNewSpace(obj));
if (obj->IsHeapObject()) {
imm32_ = reinterpret_cast<intptr_t>(handle.location());
rmode_ = RelocInfo::EMBEDDED_OBJECT;
} else {
// No relocation needed.
imm32_ = reinterpret_cast<intptr_t>(obj);
rmode_ = RelocInfo::NONE;
}
}
MemOperand::MemOperand(Register rm, int32_t offset) : Operand(rm) {
offset_ = offset;
}
// -----------------------------------------------------------------------------
// Specific instructions, constants, and masks.
static const int kNegOffset = 0x00008000;
// addiu(sp, sp, 4) aka Pop() operation or part of Pop(r)
// operations as post-increment of sp.
const Instr kPopInstruction = ADDIU | (kRegister_sp_Code << kRsShift)
| (kRegister_sp_Code << kRtShift) | (kPointerSize & kImm16Mask);
// addiu(sp, sp, -4) part of Push(r) operation as pre-decrement of sp.
const Instr kPushInstruction = ADDIU | (kRegister_sp_Code << kRsShift)
| (kRegister_sp_Code << kRtShift) | (-kPointerSize & kImm16Mask);
// sw(r, MemOperand(sp, 0))
const Instr kPushRegPattern = SW | (kRegister_sp_Code << kRsShift)
| (0 & kImm16Mask);
// lw(r, MemOperand(sp, 0))
const Instr kPopRegPattern = LW | (kRegister_sp_Code << kRsShift)
| (0 & kImm16Mask);
const Instr kLwRegFpOffsetPattern = LW | (kRegister_fp_Code << kRsShift)
| (0 & kImm16Mask);
const Instr kSwRegFpOffsetPattern = SW | (kRegister_fp_Code << kRsShift)
| (0 & kImm16Mask);
const Instr kLwRegFpNegOffsetPattern = LW | (kRegister_fp_Code << kRsShift)
| (kNegOffset & kImm16Mask);
const Instr kSwRegFpNegOffsetPattern = SW | (kRegister_fp_Code << kRsShift)
| (kNegOffset & kImm16Mask);
// A mask for the Rt register for push, pop, lw, sw instructions.
const Instr kRtMask = kRtFieldMask;
const Instr kLwSwInstrTypeMask = 0xffe00000;
const Instr kLwSwInstrArgumentMask = ~kLwSwInstrTypeMask;
const Instr kLwSwOffsetMask = kImm16Mask;
// Spare buffer.
static const int kMinimalBufferSize = 4 * KB;
Assembler::Assembler(Isolate* arg_isolate, void* buffer, int buffer_size)
: AssemblerBase(arg_isolate),
positions_recorder_(this),
emit_debug_code_(FLAG_debug_code) {
if (buffer == NULL) {
// Do our own buffer management.
if (buffer_size <= kMinimalBufferSize) {
buffer_size = kMinimalBufferSize;
if (isolate()->assembler_spare_buffer() != NULL) {
buffer = isolate()->assembler_spare_buffer();
isolate()->set_assembler_spare_buffer(NULL);
}
}
if (buffer == NULL) {
buffer_ = NewArray<byte>(buffer_size);
} else {
buffer_ = static_cast<byte*>(buffer);
}
buffer_size_ = buffer_size;
own_buffer_ = true;
} else {
// Use externally provided buffer instead.
ASSERT(buffer_size > 0);
buffer_ = static_cast<byte*>(buffer);
buffer_size_ = buffer_size;
own_buffer_ = false;
}
// Set up buffer pointers.
ASSERT(buffer_ != NULL);
pc_ = buffer_;
reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
last_trampoline_pool_end_ = 0;
no_trampoline_pool_before_ = 0;
trampoline_pool_blocked_nesting_ = 0;
// We leave space (16 * kTrampolineSlotsSize)
// for BlockTrampolinePoolScope buffer.
next_buffer_check_ = kMaxBranchOffset - kTrampolineSlotsSize * 16;
internal_trampoline_exception_ = false;
last_bound_pos_ = 0;
trampoline_emitted_ = false;
unbound_labels_count_ = 0;
block_buffer_growth_ = false;
ClearRecordedAstId();
}
Assembler::~Assembler() {
if (own_buffer_) {
if (isolate()->assembler_spare_buffer() == NULL &&
buffer_size_ == kMinimalBufferSize) {
isolate()->set_assembler_spare_buffer(buffer_);
} else {
DeleteArray(buffer_);
}
}
}
void Assembler::GetCode(CodeDesc* desc) {
ASSERT(pc_ <= reloc_info_writer.pos()); // No overlap.
// Set up code descriptor.
desc->buffer = buffer_;
desc->buffer_size = buffer_size_;
desc->instr_size = pc_offset();
desc->reloc_size = (buffer_ + buffer_size_) - reloc_info_writer.pos();
}
void Assembler::Align(int m) {
ASSERT(m >= 4 && IsPowerOf2(m));
while ((pc_offset() & (m - 1)) != 0) {
nop();
}
}
void Assembler::CodeTargetAlign() {
// No advantage to aligning branch/call targets to more than
// single instruction, that I am aware of.
Align(4);
}
Register Assembler::GetRtReg(Instr instr) {
Register rt;
rt.code_ = (instr & kRtFieldMask) >> kRtShift;
return rt;
}
Register Assembler::GetRsReg(Instr instr) {
Register rs;
rs.code_ = (instr & kRsFieldMask) >> kRsShift;
return rs;
}
Register Assembler::GetRdReg(Instr instr) {
Register rd;
rd.code_ = (instr & kRdFieldMask) >> kRdShift;
return rd;
}
uint32_t Assembler::GetRt(Instr instr) {
return (instr & kRtFieldMask) >> kRtShift;
}
uint32_t Assembler::GetRtField(Instr instr) {
return instr & kRtFieldMask;
}
uint32_t Assembler::GetRs(Instr instr) {
return (instr & kRsFieldMask) >> kRsShift;
}
uint32_t Assembler::GetRsField(Instr instr) {
return instr & kRsFieldMask;
}
uint32_t Assembler::GetRd(Instr instr) {
return (instr & kRdFieldMask) >> kRdShift;
}
uint32_t Assembler::GetRdField(Instr instr) {
return instr & kRdFieldMask;
}
uint32_t Assembler::GetSa(Instr instr) {
return (instr & kSaFieldMask) >> kSaShift;
}
uint32_t Assembler::GetSaField(Instr instr) {
return instr & kSaFieldMask;
}
uint32_t Assembler::GetOpcodeField(Instr instr) {
return instr & kOpcodeMask;
}
uint32_t Assembler::GetFunction(Instr instr) {
return (instr & kFunctionFieldMask) >> kFunctionShift;
}
uint32_t Assembler::GetFunctionField(Instr instr) {
return instr & kFunctionFieldMask;
}
uint32_t Assembler::GetImmediate16(Instr instr) {
return instr & kImm16Mask;
}
uint32_t Assembler::GetLabelConst(Instr instr) {
return instr & ~kImm16Mask;
}
bool Assembler::IsPop(Instr instr) {
return (instr & ~kRtMask) == kPopRegPattern;
}
bool Assembler::IsPush(Instr instr) {
return (instr & ~kRtMask) == kPushRegPattern;
}
bool Assembler::IsSwRegFpOffset(Instr instr) {
return ((instr & kLwSwInstrTypeMask) == kSwRegFpOffsetPattern);
}
bool Assembler::IsLwRegFpOffset(Instr instr) {
return ((instr & kLwSwInstrTypeMask) == kLwRegFpOffsetPattern);
}
bool Assembler::IsSwRegFpNegOffset(Instr instr) {
return ((instr & (kLwSwInstrTypeMask | kNegOffset)) ==
kSwRegFpNegOffsetPattern);
}
bool Assembler::IsLwRegFpNegOffset(Instr instr) {
return ((instr & (kLwSwInstrTypeMask | kNegOffset)) ==
kLwRegFpNegOffsetPattern);
}
// Labels refer to positions in the (to be) generated code.
// There are bound, linked, and unused labels.
//
// Bound labels refer to known positions in the already
// generated code. pos() is the position the label refers to.
//
// Linked labels refer to unknown positions in the code
// to be generated; pos() is the position of the last
// instruction using the label.
// The link chain is terminated by a value in the instruction of -1,
// which is an otherwise illegal value (branch -1 is inf loop).
// The instruction 16-bit offset field addresses 32-bit words, but in
// code is conv to an 18-bit value addressing bytes, hence the -4 value.
const int kEndOfChain = -4;
// Determines the end of the Jump chain (a subset of the label link chain).
const int kEndOfJumpChain = 0;
bool Assembler::IsBranch(Instr instr) {
uint32_t opcode = GetOpcodeField(instr);
uint32_t rt_field = GetRtField(instr);
uint32_t rs_field = GetRsField(instr);
uint32_t label_constant = GetLabelConst(instr);
// Checks if the instruction is a branch.
return opcode == BEQ ||
opcode == BNE ||
opcode == BLEZ ||
opcode == BGTZ ||
opcode == BEQL ||
opcode == BNEL ||
opcode == BLEZL ||
opcode == BGTZL ||
(opcode == REGIMM && (rt_field == BLTZ || rt_field == BGEZ ||
rt_field == BLTZAL || rt_field == BGEZAL)) ||
(opcode == COP1 && rs_field == BC1) || // Coprocessor branch.
label_constant == 0; // Emitted label const in reg-exp engine.
}
bool Assembler::IsBeq(Instr instr) {
return GetOpcodeField(instr) == BEQ;
}
bool Assembler::IsBne(Instr instr) {
return GetOpcodeField(instr) == BNE;
}
bool Assembler::IsJump(Instr instr) {
uint32_t opcode = GetOpcodeField(instr);
uint32_t rt_field = GetRtField(instr);
uint32_t rd_field = GetRdField(instr);
uint32_t function_field = GetFunctionField(instr);
// Checks if the instruction is a jump.
return opcode == J || opcode == JAL ||
(opcode == SPECIAL && rt_field == 0 &&
((function_field == JALR) || (rd_field == 0 && (function_field == JR))));
}
bool Assembler::IsJ(Instr instr) {
uint32_t opcode = GetOpcodeField(instr);
// Checks if the instruction is a jump.
return opcode == J;
}
bool Assembler::IsJal(Instr instr) {
return GetOpcodeField(instr) == JAL;
}
bool Assembler::IsJr(Instr instr) {
return GetOpcodeField(instr) == SPECIAL && GetFunctionField(instr) == JR;
}
bool Assembler::IsJalr(Instr instr) {
return GetOpcodeField(instr) == SPECIAL && GetFunctionField(instr) == JALR;
}
bool Assembler::IsLui(Instr instr) {
uint32_t opcode = GetOpcodeField(instr);
// Checks if the instruction is a load upper immediate.
return opcode == LUI;
}
bool Assembler::IsOri(Instr instr) {
uint32_t opcode = GetOpcodeField(instr);
// Checks if the instruction is a load upper immediate.
return opcode == ORI;
}
bool Assembler::IsNop(Instr instr, unsigned int type) {
// See Assembler::nop(type).
ASSERT(type < 32);
uint32_t opcode = GetOpcodeField(instr);
uint32_t rt = GetRt(instr);
uint32_t rs = GetRs(instr);
uint32_t sa = GetSa(instr);
// nop(type) == sll(zero_reg, zero_reg, type);
// Technically all these values will be 0 but
// this makes more sense to the reader.
bool ret = (opcode == SLL &&
rt == static_cast<uint32_t>(ToNumber(zero_reg)) &&
rs == static_cast<uint32_t>(ToNumber(zero_reg)) &&
sa == type);
return ret;
}
int32_t Assembler::GetBranchOffset(Instr instr) {
ASSERT(IsBranch(instr));
return ((int16_t)(instr & kImm16Mask)) << 2;
}
bool Assembler::IsLw(Instr instr) {
return ((instr & kOpcodeMask) == LW);
}
int16_t Assembler::GetLwOffset(Instr instr) {
ASSERT(IsLw(instr));
return ((instr & kImm16Mask));
}
Instr Assembler::SetLwOffset(Instr instr, int16_t offset) {
ASSERT(IsLw(instr));
// We actually create a new lw instruction based on the original one.
Instr temp_instr = LW | (instr & kRsFieldMask) | (instr & kRtFieldMask)
| (offset & kImm16Mask);
return temp_instr;
}
bool Assembler::IsSw(Instr instr) {
return ((instr & kOpcodeMask) == SW);
}
Instr Assembler::SetSwOffset(Instr instr, int16_t offset) {
ASSERT(IsSw(instr));
return ((instr & ~kImm16Mask) | (offset & kImm16Mask));
}
bool Assembler::IsAddImmediate(Instr instr) {
return ((instr & kOpcodeMask) == ADDIU);
}
Instr Assembler::SetAddImmediateOffset(Instr instr, int16_t offset) {
ASSERT(IsAddImmediate(instr));
return ((instr & ~kImm16Mask) | (offset & kImm16Mask));
}
bool Assembler::IsAndImmediate(Instr instr) {
return GetOpcodeField(instr) == ANDI;
}
int Assembler::target_at(int32_t pos) {
Instr instr = instr_at(pos);
if ((instr & ~kImm16Mask) == 0) {
// Emitted label constant, not part of a branch.
if (instr == 0) {
return kEndOfChain;
} else {
int32_t imm18 =((instr & static_cast<int32_t>(kImm16Mask)) << 16) >> 14;
return (imm18 + pos);
}
}
// Check we have a branch or jump instruction.
ASSERT(IsBranch(instr) || IsJ(instr) || IsLui(instr));
// Do NOT change this to <<2. We rely on arithmetic shifts here, assuming
// the compiler uses arithmectic shifts for signed integers.
if (IsBranch(instr)) {
int32_t imm18 = ((instr & static_cast<int32_t>(kImm16Mask)) << 16) >> 14;
if (imm18 == kEndOfChain) {
// EndOfChain sentinel is returned directly, not relative to pc or pos.
return kEndOfChain;
} else {
return pos + kBranchPCOffset + imm18;
}
} else if (IsLui(instr)) {
Instr instr_lui = instr_at(pos + 0 * Assembler::kInstrSize);
Instr instr_ori = instr_at(pos + 1 * Assembler::kInstrSize);
ASSERT(IsOri(instr_ori));
int32_t imm = (instr_lui & static_cast<int32_t>(kImm16Mask)) << kLuiShift;
imm |= (instr_ori & static_cast<int32_t>(kImm16Mask));
if (imm == kEndOfJumpChain) {
// EndOfChain sentinel is returned directly, not relative to pc or pos.
return kEndOfChain;
} else {
uint32_t instr_address = reinterpret_cast<int32_t>(buffer_ + pos);
int32_t delta = instr_address - imm;
ASSERT(pos > delta);
return pos - delta;
}
} else {
int32_t imm28 = (instr & static_cast<int32_t>(kImm26Mask)) << 2;
if (imm28 == kEndOfJumpChain) {
// EndOfChain sentinel is returned directly, not relative to pc or pos.
return kEndOfChain;
} else {
uint32_t instr_address = reinterpret_cast<int32_t>(buffer_ + pos);
instr_address &= kImm28Mask;
int32_t delta = instr_address - imm28;
ASSERT(pos > delta);
return pos - delta;
}
}
}
void Assembler::target_at_put(int32_t pos, int32_t target_pos) {
Instr instr = instr_at(pos);
if ((instr & ~kImm16Mask) == 0) {
ASSERT(target_pos == kEndOfChain || target_pos >= 0);
// Emitted label constant, not part of a branch.
// Make label relative to Code* of generated Code object.
instr_at_put(pos, target_pos + (Code::kHeaderSize - kHeapObjectTag));
return;
}
ASSERT(IsBranch(instr) || IsJ(instr) || IsLui(instr));
if (IsBranch(instr)) {
int32_t imm18 = target_pos - (pos + kBranchPCOffset);
ASSERT((imm18 & 3) == 0);
instr &= ~kImm16Mask;
int32_t imm16 = imm18 >> 2;
ASSERT(is_int16(imm16));
instr_at_put(pos, instr | (imm16 & kImm16Mask));
} else if (IsLui(instr)) {
Instr instr_lui = instr_at(pos + 0 * Assembler::kInstrSize);
Instr instr_ori = instr_at(pos + 1 * Assembler::kInstrSize);
ASSERT(IsOri(instr_ori));
uint32_t imm = (uint32_t)buffer_ + target_pos;
ASSERT((imm & 3) == 0);
instr_lui &= ~kImm16Mask;
instr_ori &= ~kImm16Mask;
instr_at_put(pos + 0 * Assembler::kInstrSize,
instr_lui | ((imm & kHiMask) >> kLuiShift));
instr_at_put(pos + 1 * Assembler::kInstrSize,
instr_ori | (imm & kImm16Mask));
} else {
uint32_t imm28 = (uint32_t)buffer_ + target_pos;
imm28 &= kImm28Mask;
ASSERT((imm28 & 3) == 0);
instr &= ~kImm26Mask;
uint32_t imm26 = imm28 >> 2;
ASSERT(is_uint26(imm26));
instr_at_put(pos, instr | (imm26 & kImm26Mask));
}
}
void Assembler::print(Label* L) {
if (L->is_unused()) {
PrintF("unused label\n");
} else if (L->is_bound()) {
PrintF("bound label to %d\n", L->pos());
} else if (L->is_linked()) {
Label l = *L;
PrintF("unbound label");
while (l.is_linked()) {
PrintF("@ %d ", l.pos());
Instr instr = instr_at(l.pos());
if ((instr & ~kImm16Mask) == 0) {
PrintF("value\n");
} else {
PrintF("%d\n", instr);
}
next(&l);
}
} else {
PrintF("label in inconsistent state (pos = %d)\n", L->pos_);
}
}
void Assembler::bind_to(Label* L, int pos) {
ASSERT(0 <= pos && pos <= pc_offset()); // Must have valid binding position.
int32_t trampoline_pos = kInvalidSlotPos;
if (L->is_linked() && !trampoline_emitted_) {
unbound_labels_count_--;
next_buffer_check_ += kTrampolineSlotsSize;
}
while (L->is_linked()) {
int32_t fixup_pos = L->pos();
int32_t dist = pos - fixup_pos;
next(L); // Call next before overwriting link with target at fixup_pos.
Instr instr = instr_at(fixup_pos);
if (IsBranch(instr)) {
if (dist > kMaxBranchOffset) {
if (trampoline_pos == kInvalidSlotPos) {
trampoline_pos = get_trampoline_entry(fixup_pos);
CHECK(trampoline_pos != kInvalidSlotPos);
}
ASSERT((trampoline_pos - fixup_pos) <= kMaxBranchOffset);
target_at_put(fixup_pos, trampoline_pos);
fixup_pos = trampoline_pos;
dist = pos - fixup_pos;
}
target_at_put(fixup_pos, pos);
} else {
ASSERT(IsJ(instr) || IsLui(instr));
target_at_put(fixup_pos, pos);
}
}
L->bind_to(pos);
// Keep track of the last bound label so we don't eliminate any instructions
// before a bound label.
if (pos > last_bound_pos_)
last_bound_pos_ = pos;
}
void Assembler::bind(Label* L) {
ASSERT(!L->is_bound()); // Label can only be bound once.
bind_to(L, pc_offset());
}
void Assembler::next(Label* L) {
ASSERT(L->is_linked());
int link = target_at(L->pos());
if (link == kEndOfChain) {
L->Unuse();
} else {
ASSERT(link >= 0);
L->link_to(link);
}
}
bool Assembler::is_near(Label* L) {
if (L->is_bound()) {
return ((pc_offset() - L->pos()) < kMaxBranchOffset - 4 * kInstrSize);
}
return false;
}
// We have to use a temporary register for things that can be relocated even
// if they can be encoded in the MIPS's 16 bits of immediate-offset instruction
// space. There is no guarantee that the relocated location can be similarly
// encoded.
bool Assembler::MustUseReg(RelocInfo::Mode rmode) {
return rmode != RelocInfo::NONE;
}
void Assembler::GenInstrRegister(Opcode opcode,
Register rs,
Register rt,
Register rd,
uint16_t sa,
SecondaryField func) {
ASSERT(rd.is_valid() && rs.is_valid() && rt.is_valid() && is_uint5(sa));
Instr instr = opcode | (rs.code() << kRsShift) | (rt.code() << kRtShift)
| (rd.code() << kRdShift) | (sa << kSaShift) | func;
emit(instr);
}
void Assembler::GenInstrRegister(Opcode opcode,
Register rs,
Register rt,
uint16_t msb,
uint16_t lsb,
SecondaryField func) {
ASSERT(rs.is_valid() && rt.is_valid() && is_uint5(msb) && is_uint5(lsb));
Instr instr = opcode | (rs.code() << kRsShift) | (rt.code() << kRtShift)
| (msb << kRdShift) | (lsb << kSaShift) | func;
emit(instr);
}
void Assembler::GenInstrRegister(Opcode opcode,
SecondaryField fmt,
FPURegister ft,
FPURegister fs,
FPURegister fd,
SecondaryField func) {
ASSERT(fd.is_valid() && fs.is_valid() && ft.is_valid());
ASSERT(CpuFeatures::IsEnabled(FPU));
Instr instr = opcode | fmt | (ft.code() << kFtShift) | (fs.code() << kFsShift)
| (fd.code() << kFdShift) | func;
emit(instr);
}
void Assembler::GenInstrRegister(Opcode opcode,
SecondaryField fmt,
Register rt,
FPURegister fs,
FPURegister fd,
SecondaryField func) {
ASSERT(fd.is_valid() && fs.is_valid() && rt.is_valid());
ASSERT(CpuFeatures::IsEnabled(FPU));
Instr instr = opcode | fmt | (rt.code() << kRtShift)
| (fs.code() << kFsShift) | (fd.code() << kFdShift) | func;
emit(instr);
}
void Assembler::GenInstrRegister(Opcode opcode,
SecondaryField fmt,
Register rt,
FPUControlRegister fs,
SecondaryField func) {
ASSERT(fs.is_valid() && rt.is_valid());
ASSERT(CpuFeatures::IsEnabled(FPU));
Instr instr =
opcode | fmt | (rt.code() << kRtShift) | (fs.code() << kFsShift) | func;
emit(instr);
}
// Instructions with immediate value.
// Registers are in the order of the instruction encoding, from left to right.
void Assembler::GenInstrImmediate(Opcode opcode,
Register rs,
Register rt,
int32_t j) {
ASSERT(rs.is_valid() && rt.is_valid() && (is_int16(j) || is_uint16(j)));
Instr instr = opcode | (rs.code() << kRsShift) | (rt.code() << kRtShift)
| (j & kImm16Mask);
emit(instr);
}
void Assembler::GenInstrImmediate(Opcode opcode,
Register rs,
SecondaryField SF,
int32_t j) {
ASSERT(rs.is_valid() && (is_int16(j) || is_uint16(j)));
Instr instr = opcode | (rs.code() << kRsShift) | SF | (j & kImm16Mask);
emit(instr);
}
void Assembler::GenInstrImmediate(Opcode opcode,
Register rs,
FPURegister ft,
int32_t j) {
ASSERT(rs.is_valid() && ft.is_valid() && (is_int16(j) || is_uint16(j)));
ASSERT(CpuFeatures::IsEnabled(FPU));
Instr instr = opcode | (rs.code() << kRsShift) | (ft.code() << kFtShift)
| (j & kImm16Mask);
emit(instr);
}
void Assembler::GenInstrJump(Opcode opcode,
uint32_t address) {
BlockTrampolinePoolScope block_trampoline_pool(this);
ASSERT(is_uint26(address));
Instr instr = opcode | address;
emit(instr);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
// Returns the next free trampoline entry.
int32_t Assembler::get_trampoline_entry(int32_t pos) {
int32_t trampoline_entry = kInvalidSlotPos;
if (!internal_trampoline_exception_) {
if (trampoline_.start() > pos) {
trampoline_entry = trampoline_.take_slot();
}
if (kInvalidSlotPos == trampoline_entry) {
internal_trampoline_exception_ = true;
}
}
return trampoline_entry;
}
uint32_t Assembler::jump_address(Label* L) {
int32_t target_pos;
if (L->is_bound()) {
target_pos = L->pos();
} else {
if (L->is_linked()) {
target_pos = L->pos(); // L's link.
L->link_to(pc_offset());
} else {
L->link_to(pc_offset());
return kEndOfJumpChain;
}
}
uint32_t imm = (uint32_t)buffer_ + target_pos;
ASSERT((imm & 3) == 0);
return imm;
}
int32_t Assembler::branch_offset(Label* L, bool jump_elimination_allowed) {
int32_t target_pos;
if (L->is_bound()) {
target_pos = L->pos();
} else {
if (L->is_linked()) {
target_pos = L->pos();
L->link_to(pc_offset());
} else {
L->link_to(pc_offset());
if (!trampoline_emitted_) {
unbound_labels_count_++;
next_buffer_check_ -= kTrampolineSlotsSize;
}
return kEndOfChain;
}
}
int32_t offset = target_pos - (pc_offset() + kBranchPCOffset);
ASSERT((offset & 3) == 0);
ASSERT(is_int16(offset >> 2));
return offset;
}
void Assembler::label_at_put(Label* L, int at_offset) {
int target_pos;
if (L->is_bound()) {
target_pos = L->pos();
instr_at_put(at_offset, target_pos + (Code::kHeaderSize - kHeapObjectTag));
} else {
if (L->is_linked()) {
target_pos = L->pos(); // L's link.
int32_t imm18 = target_pos - at_offset;
ASSERT((imm18 & 3) == 0);
int32_t imm16 = imm18 >> 2;
ASSERT(is_int16(imm16));
instr_at_put(at_offset, (imm16 & kImm16Mask));
} else {
target_pos = kEndOfChain;
instr_at_put(at_offset, 0);
if (!trampoline_emitted_) {
unbound_labels_count_++;
next_buffer_check_ -= kTrampolineSlotsSize;
}
}
L->link_to(at_offset);
}
}
//------- Branch and jump instructions --------
void Assembler::b(int16_t offset) {
beq(zero_reg, zero_reg, offset);
}
void Assembler::bal(int16_t offset) {
positions_recorder()->WriteRecordedPositions();
bgezal(zero_reg, offset);
}
void Assembler::beq(Register rs, Register rt, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(BEQ, rs, rt, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bgez(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(REGIMM, rs, BGEZ, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bgezal(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
positions_recorder()->WriteRecordedPositions();
GenInstrImmediate(REGIMM, rs, BGEZAL, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bgtz(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(BGTZ, rs, zero_reg, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::blez(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(BLEZ, rs, zero_reg, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bltz(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(REGIMM, rs, BLTZ, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bltzal(Register rs, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
positions_recorder()->WriteRecordedPositions();
GenInstrImmediate(REGIMM, rs, BLTZAL, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::bne(Register rs, Register rt, int16_t offset) {
BlockTrampolinePoolScope block_trampoline_pool(this);
GenInstrImmediate(BNE, rs, rt, offset);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::j(int32_t target) {
#if DEBUG
// Get pc of delay slot.
uint32_t ipc = reinterpret_cast<uint32_t>(pc_ + 1 * kInstrSize);
bool in_range = ((uint32_t)(ipc^target) >> (kImm26Bits+kImmFieldShift)) == 0;
ASSERT(in_range && ((target & 3) == 0));
#endif
GenInstrJump(J, target >> 2);
}
void Assembler::jr(Register rs) {
BlockTrampolinePoolScope block_trampoline_pool(this);
if (rs.is(ra)) {
positions_recorder()->WriteRecordedPositions();
}
GenInstrRegister(SPECIAL, rs, zero_reg, zero_reg, 0, JR);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::jal(int32_t target) {
#ifdef DEBUG
// Get pc of delay slot.
uint32_t ipc = reinterpret_cast<uint32_t>(pc_ + 1 * kInstrSize);
bool in_range = ((uint32_t)(ipc^target) >> (kImm26Bits+kImmFieldShift)) == 0;
ASSERT(in_range && ((target & 3) == 0));
#endif
positions_recorder()->WriteRecordedPositions();
GenInstrJump(JAL, target >> 2);
}
void Assembler::jalr(Register rs, Register rd) {
BlockTrampolinePoolScope block_trampoline_pool(this);
positions_recorder()->WriteRecordedPositions();
GenInstrRegister(SPECIAL, rs, zero_reg, rd, 0, JALR);
BlockTrampolinePoolFor(1); // For associated delay slot.
}
void Assembler::j_or_jr(int32_t target, Register rs) {
// Get pc of delay slot.
uint32_t ipc = reinterpret_cast<uint32_t>(pc_ + 1 * kInstrSize);
bool in_range = ((uint32_t)(ipc^target) >> (kImm26Bits+kImmFieldShift)) == 0;
if (in_range) {
j(target);
} else {
jr(t9);
}
}
void Assembler::jal_or_jalr(int32_t target, Register rs) {
// Get pc of delay slot.
uint32_t ipc = reinterpret_cast<uint32_t>(pc_ + 1 * kInstrSize);
bool in_range = ((uint32_t)(ipc^target) >> (kImm26Bits+kImmFieldShift)) == 0;
if (in_range) {
jal(target);
} else {
jalr(t9);
}
}
//-------Data-processing-instructions---------
// Arithmetic.
void Assembler::addu(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, ADDU);
}
void Assembler::addiu(Register rd, Register rs, int32_t j) {
GenInstrImmediate(ADDIU, rs, rd, j);
}
void Assembler::subu(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SUBU);
}
void Assembler::mul(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL2, rs, rt, rd, 0, MUL);
}
void Assembler::mult(Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, zero_reg, 0, MULT);
}
void Assembler::multu(Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, zero_reg, 0, MULTU);
}
void Assembler::div(Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, zero_reg, 0, DIV);
}
void Assembler::divu(Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, zero_reg, 0, DIVU);
}
// Logical.
void Assembler::and_(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, AND);
}
void Assembler::andi(Register rt, Register rs, int32_t j) {
ASSERT(is_uint16(j));
GenInstrImmediate(ANDI, rs, rt, j);
}
void Assembler::or_(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, OR);
}
void Assembler::ori(Register rt, Register rs, int32_t j) {
ASSERT(is_uint16(j));
GenInstrImmediate(ORI, rs, rt, j);
}
void Assembler::xor_(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, XOR);
}
void Assembler::xori(Register rt, Register rs, int32_t j) {
ASSERT(is_uint16(j));
GenInstrImmediate(XORI, rs, rt, j);
}
void Assembler::nor(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, NOR);
}
// Shifts.
void Assembler::sll(Register rd,
Register rt,
uint16_t sa,
bool coming_from_nop) {
// Don't allow nop instructions in the form sll zero_reg, zero_reg to be
// generated using the sll instruction. They must be generated using
// nop(int/NopMarkerTypes) or MarkCode(int/NopMarkerTypes) pseudo
// instructions.
ASSERT(coming_from_nop || !(rd.is(zero_reg) && rt.is(zero_reg)));
GenInstrRegister(SPECIAL, zero_reg, rt, rd, sa, SLL);
}
void Assembler::sllv(Register rd, Register rt, Register rs) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SLLV);
}
void Assembler::srl(Register rd, Register rt, uint16_t sa) {
GenInstrRegister(SPECIAL, zero_reg, rt, rd, sa, SRL);
}
void Assembler::srlv(Register rd, Register rt, Register rs) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SRLV);
}
void Assembler::sra(Register rd, Register rt, uint16_t sa) {
GenInstrRegister(SPECIAL, zero_reg, rt, rd, sa, SRA);
}
void Assembler::srav(Register rd, Register rt, Register rs) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SRAV);
}
void Assembler::rotr(Register rd, Register rt, uint16_t sa) {
// Should be called via MacroAssembler::Ror.
ASSERT(rd.is_valid() && rt.is_valid() && is_uint5(sa));
ASSERT(kArchVariant == kMips32r2);
Instr instr = SPECIAL | (1 << kRsShift) | (rt.code() << kRtShift)
| (rd.code() << kRdShift) | (sa << kSaShift) | SRL;
emit(instr);
}
void Assembler::rotrv(Register rd, Register rt, Register rs) {
// Should be called via MacroAssembler::Ror.
ASSERT(rd.is_valid() && rt.is_valid() && rs.is_valid() );
ASSERT(kArchVariant == kMips32r2);
Instr instr = SPECIAL | (rs.code() << kRsShift) | (rt.code() << kRtShift)
| (rd.code() << kRdShift) | (1 << kSaShift) | SRLV;
emit(instr);
}
//------------Memory-instructions-------------
// Helper for base-reg + offset, when offset is larger than int16.
void Assembler::LoadRegPlusOffsetToAt(const MemOperand& src) {
ASSERT(!src.rm().is(at));
lui(at, src.offset_ >> kLuiShift);
ori(at, at, src.offset_ & kImm16Mask); // Load 32-bit offset.
addu(at, at, src.rm()); // Add base register.
}
void Assembler::lb(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(LB, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to load.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(LB, at, rd, 0); // Equiv to lb(rd, MemOperand(at, 0));
}
}
void Assembler::lbu(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(LBU, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to load.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(LBU, at, rd, 0); // Equiv to lbu(rd, MemOperand(at, 0));
}
}
void Assembler::lh(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(LH, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to load.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(LH, at, rd, 0); // Equiv to lh(rd, MemOperand(at, 0));
}
}
void Assembler::lhu(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(LHU, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to load.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(LHU, at, rd, 0); // Equiv to lhu(rd, MemOperand(at, 0));
}
}
void Assembler::lw(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(LW, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to load.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(LW, at, rd, 0); // Equiv to lw(rd, MemOperand(at, 0));
}
}
void Assembler::lwl(Register rd, const MemOperand& rs) {
GenInstrImmediate(LWL, rs.rm(), rd, rs.offset_);
}
void Assembler::lwr(Register rd, const MemOperand& rs) {
GenInstrImmediate(LWR, rs.rm(), rd, rs.offset_);
}
void Assembler::sb(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(SB, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to store.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(SB, at, rd, 0); // Equiv to sb(rd, MemOperand(at, 0));
}
}
void Assembler::sh(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(SH, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to store.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(SH, at, rd, 0); // Equiv to sh(rd, MemOperand(at, 0));
}
}
void Assembler::sw(Register rd, const MemOperand& rs) {
if (is_int16(rs.offset_)) {
GenInstrImmediate(SW, rs.rm(), rd, rs.offset_);
} else { // Offset > 16 bits, use multiple instructions to store.
LoadRegPlusOffsetToAt(rs);
GenInstrImmediate(SW, at, rd, 0); // Equiv to sw(rd, MemOperand(at, 0));
}
}
void Assembler::swl(Register rd, const MemOperand& rs) {
GenInstrImmediate(SWL, rs.rm(), rd, rs.offset_);
}
void Assembler::swr(Register rd, const MemOperand& rs) {
GenInstrImmediate(SWR, rs.rm(), rd, rs.offset_);
}
void Assembler::lui(Register rd, int32_t j) {
ASSERT(is_uint16(j));
GenInstrImmediate(LUI, zero_reg, rd, j);
}
//-------------Misc-instructions--------------
// Break / Trap instructions.
void Assembler::break_(uint32_t code, bool break_as_stop) {
ASSERT((code & ~0xfffff) == 0);
// We need to invalidate breaks that could be stops as well because the
// simulator expects a char pointer after the stop instruction.
// See constants-mips.h for explanation.
ASSERT((break_as_stop &&
code <= kMaxStopCode &&
code > kMaxWatchpointCode) ||
(!break_as_stop &&
(code > kMaxStopCode ||
code <= kMaxWatchpointCode)));
Instr break_instr = SPECIAL | BREAK | (code << 6);
emit(break_instr);
}
void Assembler::stop(const char* msg, uint32_t code) {
ASSERT(code > kMaxWatchpointCode);
ASSERT(code <= kMaxStopCode);
#if defined(V8_HOST_ARCH_MIPS)
break_(0x54321);
#else // V8_HOST_ARCH_MIPS
BlockTrampolinePoolFor(2);
// The Simulator will handle the stop instruction and get the message address.
// On MIPS stop() is just a special kind of break_().
break_(code, true);
emit(reinterpret_cast<Instr>(msg));
#endif
}
void Assembler::tge(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr = SPECIAL | TGE | rs.code() << kRsShift
| rt.code() << kRtShift | code << 6;
emit(instr);
}
void Assembler::tgeu(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr = SPECIAL | TGEU | rs.code() << kRsShift
| rt.code() << kRtShift | code << 6;
emit(instr);
}
void Assembler::tlt(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr =
SPECIAL | TLT | rs.code() << kRsShift | rt.code() << kRtShift | code << 6;
emit(instr);
}
void Assembler::tltu(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr =
SPECIAL | TLTU | rs.code() << kRsShift
| rt.code() << kRtShift | code << 6;
emit(instr);
}
void Assembler::teq(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr =
SPECIAL | TEQ | rs.code() << kRsShift | rt.code() << kRtShift | code << 6;
emit(instr);
}
void Assembler::tne(Register rs, Register rt, uint16_t code) {
ASSERT(is_uint10(code));
Instr instr =
SPECIAL | TNE | rs.code() << kRsShift | rt.code() << kRtShift | code << 6;
emit(instr);
}
// Move from HI/LO register.
void Assembler::mfhi(Register rd) {
GenInstrRegister(SPECIAL, zero_reg, zero_reg, rd, 0, MFHI);
}
void Assembler::mflo(Register rd) {
GenInstrRegister(SPECIAL, zero_reg, zero_reg, rd, 0, MFLO);
}
// Set on less than instructions.
void Assembler::slt(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SLT);
}
void Assembler::sltu(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, SLTU);
}
void Assembler::slti(Register rt, Register rs, int32_t j) {
GenInstrImmediate(SLTI, rs, rt, j);
}
void Assembler::sltiu(Register rt, Register rs, int32_t j) {
GenInstrImmediate(SLTIU, rs, rt, j);
}
// Conditional move.
void Assembler::movz(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, MOVZ);
}
void Assembler::movn(Register rd, Register rs, Register rt) {
GenInstrRegister(SPECIAL, rs, rt, rd, 0, MOVN);
}
void Assembler::movt(Register rd, Register rs, uint16_t cc) {
Register rt;
rt.code_ = (cc & 0x0007) << 2 | 1;
GenInstrRegister(SPECIAL, rs, rt, rd, 0, MOVCI);
}
void Assembler::movf(Register rd, Register rs, uint16_t cc) {
Register rt;
rt.code_ = (cc & 0x0007) << 2 | 0;
GenInstrRegister(SPECIAL, rs, rt, rd, 0, MOVCI);
}
// Bit twiddling.
void Assembler::clz(Register rd, Register rs) {
// Clz instr requires same GPR number in 'rd' and 'rt' fields.
GenInstrRegister(SPECIAL2, rs, rd, rd, 0, CLZ);
}
void Assembler::ins_(Register rt, Register rs, uint16_t pos, uint16_t size) {
// Should be called via MacroAssembler::Ins.
// Ins instr has 'rt' field as dest, and two uint5: msb, lsb.
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(SPECIAL3, rs, rt, pos + size - 1, pos, INS);
}
void Assembler::ext_(Register rt, Register rs, uint16_t pos, uint16_t size) {
// Should be called via MacroAssembler::Ext.
// Ext instr has 'rt' field as dest, and two uint5: msb, lsb.
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(SPECIAL3, rs, rt, size - 1, pos, EXT);
}
//--------Coprocessor-instructions----------------
// Load, store, move.
void Assembler::lwc1(FPURegister fd, const MemOperand& src) {
GenInstrImmediate(LWC1, src.rm(), fd, src.offset_);
}
void Assembler::ldc1(FPURegister fd, const MemOperand& src) {
// Workaround for non-8-byte alignment of HeapNumber, convert 64-bit
// load to two 32-bit loads.
GenInstrImmediate(LWC1, src.rm(), fd, src.offset_);
FPURegister nextfpreg;
nextfpreg.setcode(fd.code() + 1);
GenInstrImmediate(LWC1, src.rm(), nextfpreg, src.offset_ + 4);
}
void Assembler::swc1(FPURegister fd, const MemOperand& src) {
GenInstrImmediate(SWC1, src.rm(), fd, src.offset_);
}
void Assembler::sdc1(FPURegister fd, const MemOperand& src) {
// Workaround for non-8-byte alignment of HeapNumber, convert 64-bit
// store to two 32-bit stores.
GenInstrImmediate(SWC1, src.rm(), fd, src.offset_);
FPURegister nextfpreg;
nextfpreg.setcode(fd.code() + 1);
GenInstrImmediate(SWC1, src.rm(), nextfpreg, src.offset_ + 4);
}
void Assembler::mtc1(Register rt, FPURegister fs) {
GenInstrRegister(COP1, MTC1, rt, fs, f0);
}
void Assembler::mfc1(Register rt, FPURegister fs) {
GenInstrRegister(COP1, MFC1, rt, fs, f0);
}
void Assembler::ctc1(Register rt, FPUControlRegister fs) {
GenInstrRegister(COP1, CTC1, rt, fs);
}
void Assembler::cfc1(Register rt, FPUControlRegister fs) {
GenInstrRegister(COP1, CFC1, rt, fs);
}
void Assembler::DoubleAsTwoUInt32(double d, uint32_t* lo, uint32_t* hi) {
uint64_t i;
memcpy(&i, &d, 8);
*lo = i & 0xffffffff;
*hi = i >> 32;
}
// Arithmetic.
void Assembler::add_d(FPURegister fd, FPURegister fs, FPURegister ft) {
GenInstrRegister(COP1, D, ft, fs, fd, ADD_D);
}
void Assembler::sub_d(FPURegister fd, FPURegister fs, FPURegister ft) {
GenInstrRegister(COP1, D, ft, fs, fd, SUB_D);
}
void Assembler::mul_d(FPURegister fd, FPURegister fs, FPURegister ft) {
GenInstrRegister(COP1, D, ft, fs, fd, MUL_D);
}
void Assembler::div_d(FPURegister fd, FPURegister fs, FPURegister ft) {
GenInstrRegister(COP1, D, ft, fs, fd, DIV_D);
}
void Assembler::abs_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, ABS_D);
}
void Assembler::mov_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, MOV_D);
}
void Assembler::neg_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, NEG_D);
}
void Assembler::sqrt_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, SQRT_D);
}
// Conversions.
void Assembler::cvt_w_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, CVT_W_S);
}
void Assembler::cvt_w_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, CVT_W_D);
}
void Assembler::trunc_w_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, TRUNC_W_S);
}
void Assembler::trunc_w_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, TRUNC_W_D);
}
void Assembler::round_w_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, ROUND_W_S);
}
void Assembler::round_w_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, ROUND_W_D);
}
void Assembler::floor_w_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, FLOOR_W_S);
}
void Assembler::floor_w_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, FLOOR_W_D);
}
void Assembler::ceil_w_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, CEIL_W_S);
}
void Assembler::ceil_w_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, CEIL_W_D);
}
void Assembler::cvt_l_s(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, S, f0, fs, fd, CVT_L_S);
}
void Assembler::cvt_l_d(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, D, f0, fs, fd, CVT_L_D);
}
void Assembler::trunc_l_s(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, S, f0, fs, fd, TRUNC_L_S);
}
void Assembler::trunc_l_d(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, D, f0, fs, fd, TRUNC_L_D);
}
void Assembler::round_l_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, ROUND_L_S);
}
void Assembler::round_l_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, ROUND_L_D);
}
void Assembler::floor_l_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, FLOOR_L_S);
}
void Assembler::floor_l_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, FLOOR_L_D);
}
void Assembler::ceil_l_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, CEIL_L_S);
}
void Assembler::ceil_l_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, CEIL_L_D);
}
void Assembler::cvt_s_w(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, W, f0, fs, fd, CVT_S_W);
}
void Assembler::cvt_s_l(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, L, f0, fs, fd, CVT_S_L);
}
void Assembler::cvt_s_d(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, D, f0, fs, fd, CVT_S_D);
}
void Assembler::cvt_d_w(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, W, f0, fs, fd, CVT_D_W);
}
void Assembler::cvt_d_l(FPURegister fd, FPURegister fs) {
ASSERT(kArchVariant == kMips32r2);
GenInstrRegister(COP1, L, f0, fs, fd, CVT_D_L);
}
void Assembler::cvt_d_s(FPURegister fd, FPURegister fs) {
GenInstrRegister(COP1, S, f0, fs, fd, CVT_D_S);
}
// Conditions.
void Assembler::c(FPUCondition cond, SecondaryField fmt,
FPURegister fs, FPURegister ft, uint16_t cc) {
ASSERT(CpuFeatures::IsEnabled(FPU));
ASSERT(is_uint3(cc));
ASSERT((fmt & ~(31 << kRsShift)) == 0);
Instr instr = COP1 | fmt | ft.code() << 16 | fs.code() << kFsShift
| cc << 8 | 3 << 4 | cond;
emit(instr);
}
void Assembler::fcmp(FPURegister src1, const double src2,
FPUCondition cond) {
ASSERT(CpuFeatures::IsEnabled(FPU));
ASSERT(src2 == 0.0);
mtc1(zero_reg, f14);
cvt_d_w(f14, f14);
c(cond, D, src1, f14, 0);
}
void Assembler::bc1f(int16_t offset, uint16_t cc) {
ASSERT(CpuFeatures::IsEnabled(FPU));
ASSERT(is_uint3(cc));
Instr instr = COP1 | BC1 | cc << 18 | 0 << 16 | (offset & kImm16Mask);
emit(instr);
}
void Assembler::bc1t(int16_t offset, uint16_t cc) {
ASSERT(CpuFeatures::IsEnabled(FPU));
ASSERT(is_uint3(cc));
Instr instr = COP1 | BC1 | cc << 18 | 1 << 16 | (offset & kImm16Mask);
emit(instr);
}
// Debugging.
void Assembler::RecordJSReturn() {
positions_recorder()->WriteRecordedPositions();
CheckBuffer();
RecordRelocInfo(RelocInfo::JS_RETURN);
}
void Assembler::RecordDebugBreakSlot() {
positions_recorder()->WriteRecordedPositions();
CheckBuffer();
RecordRelocInfo(RelocInfo::DEBUG_BREAK_SLOT);
}
void Assembler::RecordComment(const char* msg) {
if (FLAG_code_comments) {
CheckBuffer();
RecordRelocInfo(RelocInfo::COMMENT, reinterpret_cast<intptr_t>(msg));
}
}
int Assembler::RelocateInternalReference(byte* pc, intptr_t pc_delta) {
Instr instr = instr_at(pc);
ASSERT(IsJ(instr) || IsLui(instr));
if (IsLui(instr)) {
Instr instr_lui = instr_at(pc + 0 * Assembler::kInstrSize);
Instr instr_ori = instr_at(pc + 1 * Assembler::kInstrSize);
ASSERT(IsOri(instr_ori));
int32_t imm = (instr_lui & static_cast<int32_t>(kImm16Mask)) << kLuiShift;
imm |= (instr_ori & static_cast<int32_t>(kImm16Mask));
if (imm == kEndOfJumpChain) {
return 0; // Number of instructions patched.
}
imm += pc_delta;
ASSERT((imm & 3) == 0);
instr_lui &= ~kImm16Mask;
instr_ori &= ~kImm16Mask;
instr_at_put(pc + 0 * Assembler::kInstrSize,
instr_lui | ((imm >> kLuiShift) & kImm16Mask));
instr_at_put(pc + 1 * Assembler::kInstrSize,
instr_ori | (imm & kImm16Mask));
return 2; // Number of instructions patched.
} else {
uint32_t imm28 = (instr & static_cast<int32_t>(kImm26Mask)) << 2;
if ((int32_t)imm28 == kEndOfJumpChain) {
return 0; // Number of instructions patched.
}
imm28 += pc_delta;
imm28 &= kImm28Mask;
ASSERT((imm28 & 3) == 0);
instr &= ~kImm26Mask;
uint32_t imm26 = imm28 >> 2;
ASSERT(is_uint26(imm26));
instr_at_put(pc, instr | (imm26 & kImm26Mask));
return 1; // Number of instructions patched.
}
}
void Assembler::GrowBuffer() {
if (!own_buffer_) FATAL("external code buffer is too small");
// Compute new buffer size.
CodeDesc desc; // The new buffer.
if (buffer_size_ < 4*KB) {
desc.buffer_size = 4*KB;
} else if (buffer_size_ < 1*MB) {
desc.buffer_size = 2*buffer_size_;
} else {
desc.buffer_size = buffer_size_ + 1*MB;
}
CHECK_GT(desc.buffer_size, 0); // No overflow.
// Set up new buffer.
desc.buffer = NewArray<byte>(desc.buffer_size);
desc.instr_size = pc_offset();
desc.reloc_size = (buffer_ + buffer_size_) - reloc_info_writer.pos();
// Copy the data.
int pc_delta = desc.buffer - buffer_;
int rc_delta = (desc.buffer + desc.buffer_size) - (buffer_ + buffer_size_);
memmove(desc.buffer, buffer_, desc.instr_size);
memmove(reloc_info_writer.pos() + rc_delta,
reloc_info_writer.pos(), desc.reloc_size);
// Switch buffers.
DeleteArray(buffer_);
buffer_ = desc.buffer;
buffer_size_ = desc.buffer_size;
pc_ += pc_delta;
reloc_info_writer.Reposition(reloc_info_writer.pos() + rc_delta,
reloc_info_writer.last_pc() + pc_delta);
// Relocate runtime entries.
for (RelocIterator it(desc); !it.done(); it.next()) {
RelocInfo::Mode rmode = it.rinfo()->rmode();
if (rmode == RelocInfo::INTERNAL_REFERENCE) {
byte* p = reinterpret_cast<byte*>(it.rinfo()->pc());
RelocateInternalReference(p, pc_delta);
}
}
ASSERT(!overflow());
}
void Assembler::db(uint8_t data) {
CheckBuffer();
*reinterpret_cast<uint8_t*>(pc_) = data;
pc_ += sizeof(uint8_t);
}
void Assembler::dd(uint32_t data) {
CheckBuffer();
*reinterpret_cast<uint32_t*>(pc_) = data;
pc_ += sizeof(uint32_t);
}
void Assembler::RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data) {
// We do not try to reuse pool constants.
RelocInfo rinfo(pc_, rmode, data, NULL);
if (rmode >= RelocInfo::JS_RETURN && rmode <= RelocInfo::DEBUG_BREAK_SLOT) {
// Adjust code for new modes.
ASSERT(RelocInfo::IsDebugBreakSlot(rmode)
|| RelocInfo::IsJSReturn(rmode)
|| RelocInfo::IsComment(rmode)
|| RelocInfo::IsPosition(rmode));
// These modes do not need an entry in the constant pool.
}
if (rinfo.rmode() != RelocInfo::NONE) {
// Don't record external references unless the heap will be serialized.
if (rmode == RelocInfo::EXTERNAL_REFERENCE) {
#ifdef DEBUG
if (!Serializer::enabled()) {
Serializer::TooLateToEnableNow();
}
#endif
if (!Serializer::enabled() && !emit_debug_code()) {
return;
}
}
ASSERT(buffer_space() >= kMaxRelocSize); // Too late to grow buffer here.
if (rmode == RelocInfo::CODE_TARGET_WITH_ID) {
RelocInfo reloc_info_with_ast_id(pc_, rmode, RecordedAstId(), NULL);
ClearRecordedAstId();
reloc_info_writer.Write(&reloc_info_with_ast_id);
} else {
reloc_info_writer.Write(&rinfo);
}
}
}
void Assembler::BlockTrampolinePoolFor(int instructions) {
BlockTrampolinePoolBefore(pc_offset() + instructions * kInstrSize);
}
void Assembler::CheckTrampolinePool() {
// Some small sequences of instructions must not be broken up by the
// insertion of a trampoline pool; such sequences are protected by setting
// either trampoline_pool_blocked_nesting_ or no_trampoline_pool_before_,
// which are both checked here. Also, recursive calls to CheckTrampolinePool
// are blocked by trampoline_pool_blocked_nesting_.
if ((trampoline_pool_blocked_nesting_ > 0) ||
(pc_offset() < no_trampoline_pool_before_)) {
// Emission is currently blocked; make sure we try again as soon as
// possible.
if (trampoline_pool_blocked_nesting_ > 0) {
next_buffer_check_ = pc_offset() + kInstrSize;
} else {
next_buffer_check_ = no_trampoline_pool_before_;
}
return;
}
ASSERT(!trampoline_emitted_);
ASSERT(unbound_labels_count_ >= 0);
if (unbound_labels_count_ > 0) {
// First we emit jump (2 instructions), then we emit trampoline pool.
{ BlockTrampolinePoolScope block_trampoline_pool(this);
Label after_pool;
b(&after_pool);
nop();
int pool_start = pc_offset();
for (int i = 0; i < unbound_labels_count_; i++) {
uint32_t imm32;
imm32 = jump_address(&after_pool);
{ BlockGrowBufferScope block_buf_growth(this);
// Buffer growth (and relocation) must be blocked for internal
// references until associated instructions are emitted and available
// to be patched.
RecordRelocInfo(RelocInfo::INTERNAL_REFERENCE);
lui(at, (imm32 & kHiMask) >> kLuiShift);
ori(at, at, (imm32 & kImm16Mask));
}
jr(at);
nop();
}
bind(&after_pool);
trampoline_ = Trampoline(pool_start, unbound_labels_count_);
trampoline_emitted_ = true;
// As we are only going to emit trampoline once, we need to prevent any
// further emission.
next_buffer_check_ = kMaxInt;
}
} else {
// Number of branches to unbound label at this point is zero, so we can
// move next buffer check to maximum.
next_buffer_check_ = pc_offset() +
kMaxBranchOffset - kTrampolineSlotsSize * 16;
}
return;
}
Address Assembler::target_address_at(Address pc) {
Instr instr1 = instr_at(pc);
Instr instr2 = instr_at(pc + kInstrSize);
// Interpret 2 instructions generated by li: lui/ori
if ((GetOpcodeField(instr1) == LUI) && (GetOpcodeField(instr2) == ORI)) {
// Assemble the 32 bit value.
return reinterpret_cast<Address>(
(GetImmediate16(instr1) << 16) | GetImmediate16(instr2));
}
// We should never get here, force a bad address if we do.
UNREACHABLE();
return (Address)0x0;
}
// MIPS and ia32 use opposite encoding for qNaN and sNaN, such that ia32
// qNaN is a MIPS sNaN, and ia32 sNaN is MIPS qNaN. If running from a heap
// snapshot generated on ia32, the resulting MIPS sNaN must be quieted.
// OS::nan_value() returns a qNaN.
void Assembler::QuietNaN(HeapObject* object) {
HeapNumber::cast(object)->set_value(OS::nan_value());
}
// On Mips, a target address is stored in a lui/ori instruction pair, each
// of which load 16 bits of the 32-bit address to a register.
// Patching the address must replace both instr, and flush the i-cache.
//
// There is an optimization below, which emits a nop when the address
// fits in just 16 bits. This is unlikely to help, and should be benchmarked,
// and possibly removed.
void Assembler::set_target_address_at(Address pc, Address target) {
Instr instr2 = instr_at(pc + kInstrSize);
uint32_t rt_code = GetRtField(instr2);
uint32_t* p = reinterpret_cast<uint32_t*>(pc);
uint32_t itarget = reinterpret_cast<uint32_t>(target);
#ifdef DEBUG
// Check we have the result from a li macro-instruction, using instr pair.
Instr instr1 = instr_at(pc);
CHECK((GetOpcodeField(instr1) == LUI && GetOpcodeField(instr2) == ORI));
#endif
// Must use 2 instructions to insure patchable code => just use lui and ori.
// lui rt, upper-16.
// ori rt rt, lower-16.
*p = LUI | rt_code | ((itarget & kHiMask) >> kLuiShift);
*(p+1) = ORI | rt_code | (rt_code << 5) | (itarget & kImm16Mask);
// The following code is an optimization for the common case of Call()
// or Jump() which is load to register, and jump through register:
// li(t9, address); jalr(t9) (or jr(t9)).
// If the destination address is in the same 256 MB page as the call, it
// is faster to do a direct jal, or j, rather than jump thru register, since
// that lets the cpu pipeline prefetch the target address. However each
// time the address above is patched, we have to patch the direct jal/j
// instruction, as well as possibly revert to jalr/jr if we now cross a
// 256 MB page. Note that with the jal/j instructions, we do not need to
// load the register, but that code is left, since it makes it easy to
// revert this process. A further optimization could try replacing the
// li sequence with nops.
// This optimization can only be applied if the rt-code from instr2 is the
// register used for the jalr/jr. Finally, we have to skip 'jr ra', which is
// mips return. Occasionally this lands after an li().
Instr instr3 = instr_at(pc + 2 * kInstrSize);
uint32_t ipc = reinterpret_cast<uint32_t>(pc + 3 * kInstrSize);
bool in_range =
((uint32_t)(ipc ^ itarget) >> (kImm26Bits + kImmFieldShift)) == 0;
uint32_t target_field = (uint32_t)(itarget & kJumpAddrMask) >> kImmFieldShift;
bool patched_jump = false;
#ifndef ALLOW_JAL_IN_BOUNDARY_REGION
// This is a workaround to the 24k core E156 bug (affect some 34k cores also).
// Since the excluded space is only 64KB out of 256MB (0.02 %), we will just
// apply this workaround for all cores so we don't have to identify the core.
if (in_range) {
// The 24k core E156 bug has some very specific requirements, we only check
// the most simple one: if the address of the delay slot instruction is in
// the first or last 32 KB of the 256 MB segment.
uint32_t segment_mask = ((256 * MB) - 1) ^ ((32 * KB) - 1);
uint32_t ipc_segment_addr = ipc & segment_mask;
if (ipc_segment_addr == 0 || ipc_segment_addr == segment_mask)
in_range = false;
}
#endif
if (IsJalr(instr3)) {
// Try to convert JALR to JAL.
if (in_range && GetRt(instr2) == GetRs(instr3)) {
*(p+2) = JAL | target_field;
patched_jump = true;
}
} else if (IsJr(instr3)) {
// Try to convert JR to J, skip returns (jr ra).
bool is_ret = static_cast<int>(GetRs(instr3)) == ra.code();
if (in_range && !is_ret && GetRt(instr2) == GetRs(instr3)) {
*(p+2) = J | target_field;
patched_jump = true;
}
} else if (IsJal(instr3)) {
if (in_range) {
// We are patching an already converted JAL.
*(p+2) = JAL | target_field;
} else {
// Patch JAL, but out of range, revert to JALR.
// JALR rs reg is the rt reg specified in the ORI instruction.
uint32_t rs_field = GetRt(instr2) << kRsShift;
uint32_t rd_field = ra.code() << kRdShift; // Return-address (ra) reg.
*(p+2) = SPECIAL | rs_field | rd_field | JALR;
}
patched_jump = true;
} else if (IsJ(instr3)) {
if (in_range) {
// We are patching an already converted J (jump).
*(p+2) = J | target_field;
} else {
// Trying patch J, but out of range, just go back to JR.
// JR 'rs' reg is the 'rt' reg specified in the ORI instruction (instr2).
uint32_t rs_field = GetRt(instr2) << kRsShift;
*(p+2) = SPECIAL | rs_field | JR;
}
patched_jump = true;
}
CPU::FlushICache(pc, (patched_jump ? 3 : 2) * sizeof(int32_t));
}
void Assembler::JumpLabelToJumpRegister(Address pc) {
// Address pc points to lui/ori instructions.
// Jump to label may follow at pc + 2 * kInstrSize.
uint32_t* p = reinterpret_cast<uint32_t*>(pc);
#ifdef DEBUG
Instr instr1 = instr_at(pc);
#endif
Instr instr2 = instr_at(pc + 1 * kInstrSize);
Instr instr3 = instr_at(pc + 2 * kInstrSize);
bool patched = false;
if (IsJal(instr3)) {
ASSERT(GetOpcodeField(instr1) == LUI);
ASSERT(GetOpcodeField(instr2) == ORI);
uint32_t rs_field = GetRt(instr2) << kRsShift;
uint32_t rd_field = ra.code() << kRdShift; // Return-address (ra) reg.
*(p+2) = SPECIAL | rs_field | rd_field | JALR;
patched = true;
} else if (IsJ(instr3)) {
ASSERT(GetOpcodeField(instr1) == LUI);
ASSERT(GetOpcodeField(instr2) == ORI);
uint32_t rs_field = GetRt(instr2) << kRsShift;
*(p+2) = SPECIAL | rs_field | JR;
patched = true;
}
if (patched) {
CPU::FlushICache(pc+2, sizeof(Address));
}
}
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_MIPS