Index: src/arm/assembler-arm.cc |
=================================================================== |
--- src/arm/assembler-arm.cc (revision 3798) |
+++ src/arm/assembler-arm.cc (working copy) |
@@ -264,9 +264,9 @@ |
// ----------------------------------------------------------------------------- |
-// 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) |
@@ -299,14 +299,14 @@ |
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 |
}; |
@@ -327,13 +327,13 @@ |
// 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; |
@@ -351,14 +351,14 @@ |
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_); |
@@ -386,11 +386,11 @@ |
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(); |
@@ -539,7 +539,7 @@ |
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 { |
@@ -549,7 +549,7 @@ |
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; |
} |
} |
@@ -575,12 +575,12 @@ |
} |
-// 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)) { |
@@ -589,7 +589,7 @@ |
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; |
@@ -626,7 +626,7 @@ |
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_) || |
@@ -634,7 +634,7 @@ |
// 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); |
@@ -648,16 +648,16 @@ |
} |
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); |
} |
@@ -666,15 +666,15 @@ |
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)); |
@@ -684,9 +684,9 @@ |
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(); |
} |
@@ -700,15 +700,15 @@ |
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)); |
@@ -718,15 +718,15 @@ |
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(); |
} |
@@ -744,7 +744,7 @@ |
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()); |
@@ -759,7 +759,7 @@ |
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; |
@@ -782,7 +782,7 @@ |
} |
// 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); |
} |
@@ -804,7 +804,7 @@ |
} |
-// Branch instructions |
+// Branch instructions. |
void Assembler::b(int branch_offset, Condition cond) { |
ASSERT((branch_offset & 3) == 0); |
int imm24 = branch_offset >> 2; |
@@ -812,7 +812,7 @@ |
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); |
} |
@@ -849,7 +849,7 @@ |
} |
-// 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); |
@@ -886,7 +886,7 @@ |
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; |
@@ -960,7 +960,7 @@ |
} |
-// 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)); |
@@ -1029,7 +1029,7 @@ |
} |
-// 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)); |
@@ -1038,7 +1038,7 @@ |
} |
-// 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); |
@@ -1050,12 +1050,12 @@ |
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); |
@@ -1070,7 +1070,7 @@ |
} |
-// Load/Store instructions |
+// Load/Store instructions. |
void Assembler::ldr(Register dst, const MemOperand& src, Condition cond) { |
if (dst.is(pc)) { |
WriteRecordedPositions(); |
@@ -1085,7 +1085,7 @@ |
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; |
@@ -1106,6 +1106,7 @@ |
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; |
@@ -1147,17 +1148,17 @@ |
} |
-// 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 |
@@ -1177,7 +1178,7 @@ |
} |
-// 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)); |
@@ -1197,7 +1198,7 @@ |
} |
-// 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. |
@@ -1222,7 +1223,7 @@ |
} |
-// Coprocessor instructions |
+// Coprocessor instructions. |
void Assembler::cdp(Coprocessor coproc, |
int opcode_1, |
CRegister crd, |
@@ -1307,7 +1308,7 @@ |
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)); |
@@ -1346,7 +1347,7 @@ |
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)); |
@@ -1464,7 +1465,7 @@ |
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 | |
@@ -1571,14 +1572,14 @@ |
} |
-// 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 |
@@ -1612,7 +1613,7 @@ |
} |
-// Debugging |
+// Debugging. |
void Assembler::RecordJSReturn() { |
WriteRecordedPositions(); |
CheckBuffer(); |
@@ -1665,7 +1666,7 @@ |
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; |
@@ -1676,20 +1677,20 @@ |
} |
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; |
@@ -1697,11 +1698,11 @@ |
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 && |
@@ -1716,16 +1717,16 @@ |
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) { |
@@ -1752,7 +1753,7 @@ |
// 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 |
@@ -1778,10 +1779,11 @@ |
// 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; |
} |
@@ -1795,23 +1797,23 @@ |
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 && |
@@ -1819,8 +1821,8 @@ |
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; |