// -----------------------------------------------------------------------------
-// Implementation of Assembler
+// Implementation of Assembler.
-// Instruction encoding bits
+// Instruction encoding bits.
enum {
H = 1 << 5, // halfword (or byte)
S6 = 1 << 6, // signed (or unsigned)
B26 = 1 << 26,
B27 = 1 << 27,
- // Instruction bit masks
+ // Instruction bit masks.
RdMask = 15 << 12, // in str instruction
CondMask = 15 << 28,
CoprocessorMask = 15 << 8,
OpCodeMask = 15 << 21, // in data-processing instructions
Imm24Mask = (1 << 24) - 1,
Off12Mask = (1 << 12) - 1,
- // Reserved condition
+ // Reserved condition.
nv = 15 << 28
};
// ldr pc, [pc, #XXX]
const Instr kLdrPCPattern = al | B26 | L | pc.code() * B16;
-// spare_buffer_
+// Spare buffer.
static const int kMinimalBufferSize = 4*KB;
static byte* spare_buffer_ = NULL;
Assembler::Assembler(void* buffer, int buffer_size) {
if (buffer == NULL) {
- // do our own buffer management
+ // Do our own buffer management.
if (buffer_size <= kMinimalBufferSize) {
buffer_size = kMinimalBufferSize;
own_buffer_ = true;
} else {
- // use externally provided buffer instead
+ // Use externally provided buffer instead.
ASSERT(buffer_size > 0);
buffer_ = static_cast<byte*>(buffer);
buffer_size_ = buffer_size;
own_buffer_ = false;
}
- // setup buffer pointers
+ // Setup buffer pointers.
ASSERT(buffer_ != NULL);
pc_ = buffer_;
reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
void Assembler::GetCode(CodeDesc* desc) {
- // emit constant pool if necessary
+ // Emit constant pool if necessary.
CheckConstPool(true, false);
ASSERT(num_prinfo_ == 0);
- // setup desc
+ // Setup code descriptor.
desc->buffer = buffer_;
desc->buffer_size = buffer_size_;
desc->instr_size = pc_offset();
void Assembler::link_to(Label* L, Label* appendix) {
if (appendix->is_linked()) {
if (L->is_linked()) {
- // append appendix to L's list
+ // Append appendix to L's list.
int fixup_pos;
int link = L->pos();
do {
ASSERT(link == kEndOfChain);
target_at_put(fixup_pos, appendix->pos());
} else {
- // L is empty, simply use appendix
+ // L is empty, simply use appendix.
*L = *appendix;
}
}
}
-// Low-level code emission routines depending on the addressing mode
+// Low-level code emission routines depending on the addressing mode.
static bool fits_shifter(uint32_t imm32,
uint32_t* rotate_imm,
uint32_t* immed_8,
Instr* instr) {
- // imm32 must be unsigned
+ // imm32 must be unsigned.
for (int rot = 0; rot < 16; rot++) {
uint32_t imm8 = (imm32 << 2*rot) | (imm32 >> (32 - 2*rot));
if ((imm8 <= 0xff)) {
return true;
}
}
- // if the opcode is mov or mvn and if ~imm32 fits, change the opcode
+ // If the opcode is mov or mvn and if ~imm32 fits, change the opcode.
if (instr != NULL && (*instr & 0xd*B21) == 0xd*B21) {
if (fits_shifter(~imm32, rotate_imm, immed_8, NULL)) {
*instr ^= 0x2*B21;
CheckBuffer();
ASSERT((instr & ~(CondMask | OpCodeMask | S)) == 0);
if (!x.rm_.is_valid()) {
- // immediate
+ // Immediate.
uint32_t rotate_imm;
uint32_t immed_8;
if (MustUseIp(x.rmode_) ||
// The immediate operand cannot be encoded as a shifter operand, so load
// it first to register ip and change the original instruction to use ip.
// However, if the original instruction is a 'mov rd, x' (not setting the
- // condition code), then replace it with a 'ldr rd, [pc]'
+ // condition code), then replace it with a 'ldr rd, [pc]'.
RecordRelocInfo(x.rmode_, x.imm32_);
CHECK(!rn.is(ip)); // rn should never be ip, or will be trashed
Condition cond = static_cast<Condition>(instr & CondMask);
}
instr |= I | rotate_imm*B8 | immed_8;
} else if (!x.rs_.is_valid()) {
- // immediate shift
+ // Immediate shift.
instr |= x.shift_imm_*B7 | x.shift_op_ | x.rm_.code();
} else {
- // register shift
+ // Register shift.
ASSERT(!rn.is(pc) && !rd.is(pc) && !x.rm_.is(pc) && !x.rs_.is(pc));
instr |= x.rs_.code()*B8 | x.shift_op_ | B4 | x.rm_.code();
}
emit(instr | rn.code()*B16 | rd.code()*B12);
if (rn.is(pc) || x.rm_.is(pc))
- // block constant pool emission for one instruction after reading pc
+ // Block constant pool emission for one instruction after reading pc.
BlockConstPoolBefore(pc_offset() + kInstrSize);
}
ASSERT((instr & ~(CondMask | B | L)) == B26);
int am = x.am_;
if (!x.rm_.is_valid()) {
- // immediate offset
+ // Immediate offset.
int offset_12 = x.offset_;
if (offset_12 < 0) {
offset_12 = -offset_12;
am ^= U;
}
if (!is_uint12(offset_12)) {
- // immediate offset cannot be encoded, load it first to register ip
- // rn (and rd in a load) should never be ip, or will be trashed
+ // Immediate offset cannot be encoded, load it first to register ip
+ // rn (and rd in a load) should never be ip, or will be trashed.
ASSERT(!x.rn_.is(ip) && ((instr & L) == L || !rd.is(ip)));
mov(ip, Operand(x.offset_), LeaveCC,
static_cast<Condition>(instr & CondMask));
ASSERT(offset_12 >= 0); // no masking needed
instr |= offset_12;
} else {
- // register offset (shift_imm_ and shift_op_ are 0) or scaled
+ // Register offset (shift_imm_ and shift_op_ are 0) or scaled
// register offset the constructors make sure than both shift_imm_
- // and shift_op_ are initialized
+ // and shift_op_ are initialized.
ASSERT(!x.rm_.is(pc));
instr |= B25 | x.shift_imm_*B7 | x.shift_op_ | x.rm_.code();
}
ASSERT(x.rn_.is_valid());
int am = x.am_;
if (!x.rm_.is_valid()) {
- // immediate offset
+ // Immediate offset.
int offset_8 = x.offset_;
if (offset_8 < 0) {
offset_8 = -offset_8;
am ^= U;
}
if (!is_uint8(offset_8)) {
- // immediate offset cannot be encoded, load it first to register ip
- // rn (and rd in a load) should never be ip, or will be trashed
+ // Immediate offset cannot be encoded, load it first to register ip
+ // rn (and rd in a load) should never be ip, or will be trashed.
ASSERT(!x.rn_.is(ip) && ((instr & L) == L || !rd.is(ip)));
mov(ip, Operand(x.offset_), LeaveCC,
static_cast<Condition>(instr & CondMask));
ASSERT(offset_8 >= 0); // no masking needed
instr |= B | (offset_8 >> 4)*B8 | (offset_8 & 0xf);
} else if (x.shift_imm_ != 0) {
- // scaled register offset not supported, load index first
- // rn (and rd in a load) should never be ip, or will be trashed
+ // Scaled register offset not supported, load index first
+ // rn (and rd in a load) should never be ip, or will be trashed.
ASSERT(!x.rn_.is(ip) && ((instr & L) == L || !rd.is(ip)));
mov(ip, Operand(x.rm_, x.shift_op_, x.shift_imm_), LeaveCC,
static_cast<Condition>(instr & CondMask));
addrmod3(instr, rd, MemOperand(x.rn_, ip, x.am_));
return;
} else {
- // register offset
+ // Register offset.
ASSERT((am & (P|W)) == P || !x.rm_.is(pc)); // no pc index with writeback
instr |= x.rm_.code();
}
void Assembler::addrmod5(Instr instr, CRegister crd, const MemOperand& x) {
- // unindexed addressing is not encoded by this function
+ // Unindexed addressing is not encoded by this function.
ASSERT_EQ((B27 | B26),
(instr & ~(CondMask | CoprocessorMask | P | U | N | W | L)));
ASSERT(x.rn_.is_valid() && !x.rm_.is_valid());
ASSERT(is_uint8(offset_8)); // unsigned word offset must fit in a byte
ASSERT((am & (P|W)) == P || !x.rn_.is(pc)); // no pc base with writeback
- // post-indexed addressing requires W == 1; different than in addrmod2/3
+ // Post-indexed addressing requires W == 1; different than in addrmod2/3.
if ((am & P) == 0)
am |= W;
}
// Block the emission of the constant pool, since the branch instruction must
- // be emitted at the pc offset recorded by the label
+ // be emitted at the pc offset recorded by the label.
BlockConstPoolBefore(pc_offset() + kInstrSize);
return target_pos - (pc_offset() + kPcLoadDelta);
}
}
-// Branch instructions
+// Branch instructions.
void Assembler::b(int branch_offset, Condition cond) {
ASSERT((branch_offset & 3) == 0);
int imm24 = branch_offset >> 2;
emit(cond | B27 | B25 | (imm24 & Imm24Mask));
if (cond == al)
- // dead code is a good location to emit the constant pool
+ // Dead code is a good location to emit the constant pool.
CheckConstPool(false, false);
}
}
-// Data-processing instructions
+// Data-processing instructions.
void Assembler::and_(Register dst, Register src1, const Operand& src2,
SBit s, Condition cond) {
addrmod1(cond | 0*B21 | s, src1, dst, src2);
if (FLAG_push_pop_elimination &&
last_bound_pos_ <= (pc_offset() - pattern_size) &&
reloc_info_writer.last_pc() <= (pc_ - pattern_size) &&
- // pattern
+ // Pattern.
instr_at(pc_ - 1 * kInstrSize) == kPopInstruction &&
(instr_at(pc_ - 2 * kInstrSize) & ~RdMask) == kPushRegPattern) {
pc_ -= 2 * kInstrSize;
}
-// Multiply instructions
+// Multiply instructions.
void Assembler::mla(Register dst, Register src1, Register src2, Register srcA,
SBit s, Condition cond) {
ASSERT(!dst.is(pc) && !src1.is(pc) && !src2.is(pc) && !srcA.is(pc));
}
-// Miscellaneous arithmetic instructions
+// Miscellaneous arithmetic instructions.
void Assembler::clz(Register dst, Register src, Condition cond) {
// v5 and above.
ASSERT(!dst.is(pc) && !src.is(pc));
}
-// Status register access instructions
+// Status register access instructions.
void Assembler::mrs(Register dst, SRegister s, Condition cond) {
ASSERT(!dst.is(pc));
emit(cond | B24 | s | 15*B16 | dst.code()*B12);
ASSERT(fields >= B16 && fields < B20); // at least one field set
Instr instr;
if (!src.rm_.is_valid()) {
- // immediate
+ // Immediate.
uint32_t rotate_imm;
uint32_t immed_8;
if (MustUseIp(src.rmode_) ||
!fits_shifter(src.imm32_, &rotate_imm, &immed_8, NULL)) {
- // immediate operand cannot be encoded, load it first to register ip
+ // Immediate operand cannot be encoded, load it first to register ip.
RecordRelocInfo(src.rmode_, src.imm32_);
ldr(ip, MemOperand(pc, 0), cond);
msr(fields, Operand(ip), cond);
}
-// Load/Store instructions
+// Load/Store instructions.
void Assembler::ldr(Register dst, const MemOperand& src, Condition cond) {
if (dst.is(pc)) {
WriteRecordedPositions();
if (FLAG_push_pop_elimination &&
last_bound_pos_ <= (pc_offset() - pattern_size) &&
reloc_info_writer.last_pc() <= (pc_ - pattern_size) &&
- // pattern
+ // Pattern.
instr_at(pc_ - 1 * kInstrSize) == (kPopRegPattern | dst.code() * B12) &&
instr_at(pc_ - 2 * kInstrSize) == (kPushRegPattern | dst.code() * B12)) {
pc_ -= 2 * kInstrSize;
if (FLAG_push_pop_elimination &&
last_bound_pos_ <= (pc_offset() - pattern_size) &&
reloc_info_writer.last_pc() <= (pc_ - pattern_size) &&
+ // Pattern.
instr_at(pc_ - 1 * kInstrSize) == (kPushRegPattern | src.code() * B12) &&
instr_at(pc_ - 2 * kInstrSize) == kPopInstruction) {
pc_ -= 2 * kInstrSize;
}
-// Load/Store multiple instructions
+// Load/Store multiple instructions.
void Assembler::ldm(BlockAddrMode am,
Register base,
RegList dst,
Condition cond) {
- // ABI stack constraint: ldmxx base, {..sp..} base != sp is not restartable
+ // ABI stack constraint: ldmxx base, {..sp..} base != sp is not restartable.
ASSERT(base.is(sp) || (dst & sp.bit()) == 0);
addrmod4(cond | B27 | am | L, base, dst);
- // emit the constant pool after a function return implemented by ldm ..{..pc}
+ // Emit the constant pool after a function return implemented by ldm ..{..pc}.
if (cond == al && (dst & pc.bit()) != 0) {
// There is a slight chance that the ldm instruction was actually a call,
// in which case it would be wrong to return into the constant pool; we
}
-// Semaphore instructions
+// Semaphore instructions.
void Assembler::swp(Register dst, Register src, Register base, Condition cond) {
ASSERT(!dst.is(pc) && !src.is(pc) && !base.is(pc));
ASSERT(!dst.is(base) && !src.is(base));
}
-// Exception-generating instructions and debugging support
+// Exception-generating instructions and debugging support.
void Assembler::stop(const char* msg) {
#if !defined(__arm__)
// The simulator handles these special instructions and stops execution.
}
-// Coprocessor instructions
+// Coprocessor instructions.
void Assembler::cdp(Coprocessor coproc,
int opcode_1,
CRegister crd,
int option,
LFlag l,
Condition cond) {
- // unindexed addressing
+ // Unindexed addressing.
ASSERT(is_uint8(option));
emit(cond | B27 | B26 | U | l | L | rn.code()*B16 | crd.code()*B12 |
coproc*B8 | (option & 255));
int option,
LFlag l,
Condition cond) {
- // unindexed addressing
+ // Unindexed addressing.
ASSERT(is_uint8(option));
emit(cond | B27 | B26 | U | l | rn.code()*B16 | crd.code()*B12 |
coproc*B8 | (option & 255));
const Condition cond) {
// Dd = Sm (integer in Sm converted to IEEE 64-bit doubles in Dd).
// Instruction details available in ARM DDI 0406A, A8-576.
- // cond(31-28) | 11101(27-23)| D=?(22) | 11(21-20) | 1(19) |opc2=000(18-16) |
+ // cond(31-28) | 11101(27-23)| D=?(22) | 11(21-20) | 1(19) | opc2=000(18-16) |
// Vd(15-12) | 101(11-9) | sz(8)=1 | op(7)=1 | 1(6) | M=?(5) | 0(4) | Vm(3-0)
ASSERT(CpuFeatures::IsEnabled(VFP3));
emit(cond | 0xE*B24 | B23 | 0x3*B20 | B19 |
}
-// Pseudo instructions
+// Pseudo instructions.
void Assembler::lea(Register dst,
const MemOperand& x,
SBit s,
Condition cond) {
int am = x.am_;
if (!x.rm_.is_valid()) {
- // immediate offset
+ // Immediate offset.
if ((am & P) == 0) // post indexing
mov(dst, Operand(x.rn_), s, cond);
else if ((am & U) == 0) // negative indexing
}
-// Debugging
+// Debugging.
void Assembler::RecordJSReturn() {
WriteRecordedPositions();
CheckBuffer();
void Assembler::GrowBuffer() {
if (!own_buffer_) FATAL("external code buffer is too small");
- // compute new buffer size
+ // Compute new buffer size.
CodeDesc desc; // the new buffer
if (buffer_size_ < 4*KB) {
desc.buffer_size = 4*KB;
}
CHECK_GT(desc.buffer_size, 0); // no overflow
- // setup new buffer
+ // Setup 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
+ // 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
+ // Switch buffers.
DeleteArray(buffer_);
buffer_ = desc.buffer;
buffer_size_ = desc.buffer_size;
reloc_info_writer.Reposition(reloc_info_writer.pos() + rc_delta,
reloc_info_writer.last_pc() + pc_delta);
- // none of our relocation types are pc relative pointing outside the code
+ // None of our relocation types are pc relative pointing outside the code
// buffer nor pc absolute pointing inside the code buffer, so there is no need
- // to relocate any emitted relocation entries
+ // to relocate any emitted relocation entries.
- // relocate pending relocation entries
+ // Relocate pending relocation entries.
for (int i = 0; i < num_prinfo_; i++) {
RelocInfo& rinfo = prinfo_[i];
ASSERT(rinfo.rmode() != RelocInfo::COMMENT &&
void Assembler::RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data) {
RelocInfo rinfo(pc_, rmode, data); // we do not try to reuse pool constants
if (rmode >= RelocInfo::JS_RETURN && rmode <= RelocInfo::STATEMENT_POSITION) {
- // Adjust code for new modes
+ // Adjust code for new modes.
ASSERT(RelocInfo::IsJSReturn(rmode)
|| RelocInfo::IsComment(rmode)
|| RelocInfo::IsPosition(rmode));
- // these modes do not need an entry in the constant pool
+ // These modes do not need an entry in the constant pool.
} else {
ASSERT(num_prinfo_ < kMaxNumPRInfo);
prinfo_[num_prinfo_++] = rinfo;
// Make sure the constant pool is not emitted in place of the next
- // instruction for which we just recorded relocation info
+ // instruction for which we just recorded relocation info.
BlockConstPoolBefore(pc_offset() + kInstrSize);
}
if (rinfo.rmode() != RelocInfo::NONE) {
// blocked for a specific range.
next_buffer_check_ = pc_offset() + kCheckConstInterval;
- // There is nothing to do if there are no pending relocation info entries
+ // There is nothing to do if there are no pending relocation info entries.
if (num_prinfo_ == 0) return;
// We emit a constant pool at regular intervals of about kDistBetweenPools
// no_const_pool_before_, which is checked here. Also, recursive calls to
// CheckConstPool are blocked by no_const_pool_before_.
if (pc_offset() < no_const_pool_before_) {
- // Emission is currently blocked; make sure we try again as soon as possible
+ // Emission is currently blocked; make sure we try again as soon as
+ // possible.
next_buffer_check_ = no_const_pool_before_;
- // Something is wrong if emission is forced and blocked at the same time
+ // Something is wrong if emission is forced and blocked at the same time.
ASSERT(!force_emit);
return;
}
jump_instr + kInstrSize + num_prinfo_*(kInstrSize + kMaxRelocSize);
while (buffer_space() <= (max_needed_space + kGap)) GrowBuffer();
- // Block recursive calls to CheckConstPool
+ // Block recursive calls to CheckConstPool.
BlockConstPoolBefore(pc_offset() + jump_instr + kInstrSize +
num_prinfo_*kInstrSize);
// Don't bother to check for the emit calls below.
next_buffer_check_ = no_const_pool_before_;
- // Emit jump over constant pool if necessary
+ // Emit jump over constant pool if necessary.
Label after_pool;
if (require_jump) b(&after_pool);
RecordComment("[ Constant Pool");
- // Put down constant pool marker
- // "Undefined instruction" as specified by A3.1 Instruction set encoding
+ // Put down constant pool marker "Undefined instruction" as specified by
+ // A3.1 Instruction set encoding.
emit(0x03000000 | num_prinfo_);
- // Emit constant pool entries
+ // Emit constant pool entries.
for (int i = 0; i < num_prinfo_; i++) {
RelocInfo& rinfo = prinfo_[i];
ASSERT(rinfo.rmode() != RelocInfo::COMMENT &&
rinfo.rmode() != RelocInfo::STATEMENT_POSITION);
Instr instr = instr_at(rinfo.pc());
- // Instruction to patch must be a ldr/str [pc, #offset]
- // P and U set, B and W clear, Rn == pc, offset12 still 0
+ // Instruction to patch must be a ldr/str [pc, #offset].
+ // P and U set, B and W clear, Rn == pc, offset12 still 0.
ASSERT((instr & (7*B25 | P | U | B | W | 15*B16 | Off12Mask)) ==
(2*B25 | P | U | pc.code()*B16));
int delta = pc_ - rinfo.pc() - 8;
}
// -----------------------------------------------------------------------------
-// Implementation of Assembler
+// Implementation of Assembler.
// Emit a single byte. Must always be inlined.
#define EMIT(x) \
static void InitCoverageLog();
#endif
-// spare_buffer_
+// Spare buffer.
byte* Assembler::spare_buffer_ = NULL;
Assembler::Assembler(void* buffer, int buffer_size) {
if (buffer == NULL) {
- // do our own buffer management
+ // Do our own buffer management.
if (buffer_size <= kMinimalBufferSize) {
buffer_size = kMinimalBufferSize;
buffer_size_ = buffer_size;
own_buffer_ = true;
} else {
- // use externally provided buffer instead
+ // Use externally provided buffer instead.
ASSERT(buffer_size > 0);
buffer_ = static_cast<byte*>(buffer);
buffer_size_ = buffer_size;
}
#endif
- // setup buffer pointers
+ // Setup buffer pointers.
ASSERT(buffer_ != NULL);
pc_ = buffer_;
reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
void Assembler::GetCode(CodeDesc* desc) {
- // finalize code
- // (at this point overflow() may be true, but the gap ensures that
- // we are still not overlapping instructions and relocation info)
- ASSERT(pc_ <= reloc_info_writer.pos()); // no overlap
- // setup desc
+ // Finalize code (at this point overflow() may be true, but the gap ensures
+ // that we are still not overlapping instructions and relocation info).
+ ASSERT(pc_ <= reloc_info_writer.pos()); // No overlap.
+ // Setup code descriptor.
desc->buffer = buffer_;
desc->buffer_size = buffer_size_;
desc->instr_size = pc_offset();
void Assembler::pop(Register dst) {
ASSERT(reloc_info_writer.last_pc() != NULL);
if (FLAG_push_pop_elimination && (reloc_info_writer.last_pc() <= last_pc_)) {
- // (last_pc_ != NULL) is rolled into the above check
+ // (last_pc_ != NULL) is rolled into the above check.
// If a last_pc_ is set, we need to make sure that there has not been any
// relocation information generated between the last instruction and this
// pop instruction.
return;
} else if (instr == 0xff) { // push of an operand, convert to a move
byte op1 = last_pc_[1];
- // Check if the operation is really a push
+ // Check if the operation is really a push.
if ((op1 & 0x38) == (6 << 3)) {
op1 = (op1 & ~0x38) | static_cast<byte>(dst.code() << 3);
last_pc_[0] = 0x8b;
ASSERT(CpuFeatures::IsEnabled(CMOV));
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: 0f 40 + cc /r
+ // Opcode: 0f 40 + cc /r.
EMIT(0x0F);
EMIT(0x40 + cc);
emit_operand(dst, src);
void Assembler::xchg(Register dst, Register src) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- if (src.is(eax) || dst.is(eax)) { // Single-byte encoding
+ if (src.is(eax) || dst.is(eax)) { // Single-byte encoding.
EMIT(0x90 | (src.is(eax) ? dst.code() : src.code()));
} else {
EMIT(0x87);
if (disp.type() == Displacement::UNCONDITIONAL_JUMP) {
ASSERT(byte_at(fixup_pos - 1) == 0xE9); // jmp expected
}
- // relative address, relative to point after address
+ // Relative address, relative to point after address.
int imm32 = pos - (fixup_pos + sizeof(int32_t));
long_at_put(fixup_pos, imm32);
}
last_pc_ = NULL;
if (appendix->is_linked()) {
if (L->is_linked()) {
- // append appendix to L's list
+ // Append appendix to L's list.
Label p;
Label q = *L;
do {
disp_at_put(&p, disp);
p.Unuse(); // to avoid assertion failure in ~Label
} else {
- // L is empty, simply use appendix
+ // L is empty, simply use appendix.
*L = *appendix;
}
}
const int long_size = 5;
int offs = L->pos() - pc_offset();
ASSERT(offs <= 0);
- // 1110 1000 #32-bit disp
+ // 1110 1000 #32-bit disp.
EMIT(0xE8);
emit(offs - long_size);
} else {
- // 1110 1000 #32-bit disp
+ // 1110 1000 #32-bit disp.
EMIT(0xE8);
emit_disp(L, Displacement::OTHER);
}
int offs = L->pos() - pc_offset();
ASSERT(offs <= 0);
if (is_int8(offs - short_size)) {
- // 1110 1011 #8-bit disp
+ // 1110 1011 #8-bit disp.
EMIT(0xEB);
EMIT((offs - short_size) & 0xFF);
} else {
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
EMIT(0xE9);
emit(offs - long_size);
}
} else {
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
EMIT(0xE9);
emit_disp(L, Displacement::UNCONDITIONAL_JUMP);
}
last_pc_ = pc_;
ASSERT((0 <= cc) && (cc < 16));
if (FLAG_emit_branch_hints && hint != no_hint) EMIT(hint);
- // 0000 1111 1000 tttn #32-bit disp
+ // 0000 1111 1000 tttn #32-bit disp.
EMIT(0x0F);
EMIT(0x80 | cc);
emit(entry - (pc_ + sizeof(int32_t)), rmode);
}
-// FPU instructions
+// FPU instructions.
void Assembler::fld(int i) {
EnsureSpace ensure_space(this);
void Assembler::GrowBuffer() {
- ASSERT(overflow()); // should not call this otherwise
+ ASSERT(overflow());
if (!own_buffer_) FATAL("external code buffer is too small");
- // compute new buffer size
+ // Compute new buffer size.
CodeDesc desc; // the new buffer
if (buffer_size_ < 4*KB) {
desc.buffer_size = 4*KB;
V8::FatalProcessOutOfMemory("Assembler::GrowBuffer");
}
- // setup new buffer
+ // Setup new buffer.
desc.buffer = NewArray<byte>(desc.buffer_size);
desc.instr_size = pc_offset();
desc.reloc_size = (buffer_ + buffer_size_) - (reloc_info_writer.pos());
memset(desc.buffer, 0xCC, desc.buffer_size);
#endif
- // copy the data
+ // 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(rc_delta + reloc_info_writer.pos(),
reloc_info_writer.pos(), desc.reloc_size);
- // switch buffers
+ // Switch buffers.
if (spare_buffer_ == NULL && buffer_size_ == kMinimalBufferSize) {
spare_buffer_ = buffer_;
} else {
reloc_info_writer.Reposition(reloc_info_writer.pos() + rc_delta,
reloc_info_writer.last_pc() + pc_delta);
- // relocate runtime entries
+ // Relocate runtime entries.
for (RelocIterator it(desc); !it.done(); it.next()) {
RelocInfo::Mode rmode = it.rinfo()->rmode();
if (rmode == RelocInfo::RUNTIME_ENTRY) {
// -----------------------------------------------------------------------------
-// Implementation of Assembler
+// Implementation of Assembler.
#ifdef GENERATED_CODE_COVERAGE
static void InitCoverageLog();
Assembler::Assembler(void* buffer, int buffer_size)
: code_targets_(100) {
if (buffer == NULL) {
- // do our own buffer management
+ // Do our own buffer management.
if (buffer_size <= kMinimalBufferSize) {
buffer_size = kMinimalBufferSize;
buffer_size_ = buffer_size;
own_buffer_ = true;
} else {
- // use externally provided buffer instead
+ // Use externally provided buffer instead.
ASSERT(buffer_size > 0);
buffer_ = static_cast<byte*>(buffer);
buffer_size_ = buffer_size;
}
#endif
- // setup buffer pointers
+ // Setup buffer pointers.
ASSERT(buffer_ != NULL);
pc_ = buffer_;
reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
void Assembler::GetCode(CodeDesc* desc) {
- // finalize code
- // (at this point overflow() may be true, but the gap ensures that
- // we are still not overlapping instructions and relocation info)
- ASSERT(pc_ <= reloc_info_writer.pos()); // no overlap
- // setup desc
+ // Finalize code (at this point overflow() may be true, but the gap ensures
+ // that we are still not overlapping instructions and relocation info).
+ ASSERT(pc_ <= reloc_info_writer.pos()); // No overlap.
+ // Setup code descriptor.
desc->buffer = buffer_;
desc->buffer_size = buffer_size_;
desc->instr_size = pc_offset();
int current = L->pos();
int next = long_at(current);
while (next != current) {
- // relative address, relative to point after address
+ // Relative address, relative to point after address.
int imm32 = pos - (current + sizeof(int32_t));
long_at_put(current, imm32);
current = next;
void Assembler::GrowBuffer() {
- ASSERT(buffer_overflow()); // should not call this otherwise
+ ASSERT(buffer_overflow());
if (!own_buffer_) FATAL("external code buffer is too small");
- // compute new buffer size
+ // Compute new buffer size.
CodeDesc desc; // the new buffer
if (buffer_size_ < 4*KB) {
desc.buffer_size = 4*KB;
V8::FatalProcessOutOfMemory("Assembler::GrowBuffer");
}
- // setup new buffer
+ // Setup new buffer.
desc.buffer = NewArray<byte>(desc.buffer_size);
desc.instr_size = pc_offset();
desc.reloc_size =
memset(desc.buffer, 0xCC, desc.buffer_size);
#endif
- // copy the data
+ // Copy the data.
intptr_t pc_delta = desc.buffer - buffer_;
intptr_t rc_delta = (desc.buffer + desc.buffer_size) -
(buffer_ + buffer_size_);
memmove(rc_delta + reloc_info_writer.pos(),
reloc_info_writer.pos(), desc.reloc_size);
- // switch buffers
+ // Switch buffers.
if (spare_buffer_ == NULL && buffer_size_ == kMinimalBufferSize) {
spare_buffer_ = buffer_;
} else {
reloc_info_writer.Reposition(reloc_info_writer.pos() + rc_delta,
reloc_info_writer.last_pc() + pc_delta);
- // relocate runtime entries
+ // Relocate runtime entries.
for (RelocIterator it(desc); !it.done(); it.next()) {
RelocInfo::Mode rmode = it.rinfo()->rmode();
if (rmode == RelocInfo::INTERNAL_REFERENCE) {
}
-// Assembler Instruction implementations
+// Assembler Instruction implementations.
void Assembler::arithmetic_op(byte opcode, Register reg, const Operand& op) {
EnsureSpace ensure_space(this);
void Assembler::call(Label* L) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // 1110 1000 #32-bit disp
+ // 1110 1000 #32-bit disp.
emit(0xE8);
if (L->is_bound()) {
int offset = L->pos() - pc_offset() - sizeof(int32_t);
void Assembler::call(Handle<Code> target, RelocInfo::Mode rmode) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // 1110 1000 #32-bit disp
+ // 1110 1000 #32-bit disp.
emit(0xE8);
emit_code_target(target, rmode);
}
void Assembler::call(Register adr) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: FF /2 r64
+ // Opcode: FF /2 r64.
if (adr.high_bit()) {
emit_rex_64(adr);
}
void Assembler::call(const Operand& op) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: FF /2 m64
+ // Opcode: FF /2 m64.
emit_rex_64(op);
emit(0xFF);
emit_operand(2, op);
ASSERT(cc >= 0); // Use mov for unconditional moves.
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: REX.W 0f 40 + cc /r
+ // Opcode: REX.W 0f 40 + cc /r.
emit_rex_64(dst, src);
emit(0x0f);
emit(0x40 + cc);
ASSERT(cc >= 0);
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: REX.W 0f 40 + cc /r
+ // Opcode: REX.W 0f 40 + cc /r.
emit_rex_64(dst, src);
emit(0x0f);
emit(0x40 + cc);
ASSERT(cc >= 0);
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: 0f 40 + cc /r
+ // Opcode: 0f 40 + cc /r.
emit_optional_rex_32(dst, src);
emit(0x0f);
emit(0x40 + cc);
ASSERT(cc >= 0);
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode: 0f 40 + cc /r
+ // Opcode: 0f 40 + cc /r.
emit_optional_rex_32(dst, src);
emit(0x0f);
emit(0x40 + cc);
int offs = L->pos() - pc_offset();
ASSERT(offs <= 0);
if (is_int8(offs - short_size)) {
- // 0111 tttn #8-bit disp
+ // 0111 tttn #8-bit disp.
emit(0x70 | cc);
emit((offs - short_size) & 0xFF);
} else {
- // 0000 1111 1000 tttn #32-bit disp
+ // 0000 1111 1000 tttn #32-bit disp.
emit(0x0F);
emit(0x80 | cc);
emitl(offs - long_size);
}
} else if (L->is_linked()) {
- // 0000 1111 1000 tttn #32-bit disp
+ // 0000 1111 1000 tttn #32-bit disp.
emit(0x0F);
emit(0x80 | cc);
emitl(L->pos());
EnsureSpace ensure_space(this);
last_pc_ = pc_;
ASSERT(is_uint4(cc));
- // 0000 1111 1000 tttn #32-bit disp
+ // 0000 1111 1000 tttn #32-bit disp.
emit(0x0F);
emit(0x80 | cc);
emit_code_target(target, rmode);
int offs = L->pos() - pc_offset() - 1;
ASSERT(offs <= 0);
if (is_int8(offs - sizeof(int8_t))) {
- // 1110 1011 #8-bit disp
+ // 1110 1011 #8-bit disp.
emit(0xEB);
emit((offs - sizeof(int8_t)) & 0xFF);
} else {
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
emit(0xE9);
emitl(offs - sizeof(int32_t));
}
} else if (L->is_linked()) {
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
emit(0xE9);
emitl(L->pos());
L->link_to(pc_offset() - sizeof(int32_t));
} else {
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
ASSERT(L->is_unused());
emit(0xE9);
int32_t current = pc_offset();
void Assembler::jmp(Handle<Code> target, RelocInfo::Mode rmode) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // 1110 1001 #32-bit disp
+ // 1110 1001 #32-bit disp.
emit(0xE9);
emit_code_target(target, rmode);
}
void Assembler::jmp(Register target) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode FF/4 r64
+ // Opcode FF/4 r64.
if (target.high_bit()) {
emit_rex_64(target);
}
void Assembler::jmp(const Operand& src) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
- // Opcode FF/4 m64
+ // Opcode FF/4 m64.
emit_optional_rex_32(src);
emit(0xFF);
emit_operand(0x4, src);
}
-/*
- * Loads the ip-relative location of the src label into the target
- * location (as a 32-bit offset sign extended to 64-bit).
- */
+// Loads the ip-relative location of the src label into the target location
+// (as a 32-bit offset sign extended to 64-bit).
void Assembler::movl(const Operand& dst, Label* src) {
EnsureSpace ensure_space(this);
last_pc_ = pc_;
}
-// FPU instructions
+// FPU instructions.
void Assembler::fld(int i) {
emit(b2 + i);
}
-// SSE 2 operations
+// SSE 2 operations.
void Assembler::movsd(const Operand& dst, XMMRegister src) {
EnsureSpace ensure_space(this);
}
-// Relocation information implementations
+// Relocation information implementations.
void Assembler::RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data) {
ASSERT(rmode != RelocInfo::NONE);
projects / platform / upstream / v8.git / commitdiff