Remove unused last_pc_ in AssemblerX64.

src/x64/assembler-x64.cc

 // Copyright 2011 the V8 project authors. 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.
 //     * Redistributions 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
@@ skipping 370 matching lines @@
   if (own_buffer_) {
     memset(buffer_, 0xCC, buffer_size);  // int3
   }
 #endif
 
   // Setup buffer pointers.
   ASSERT(buffer_ != NULL);
   pc_ = buffer_;
   reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
 
-  last_pc_ = NULL;
 
 #ifdef GENERATED_CODE_COVERAGE
   InitCoverageLog();
 #endif
 }
 
 
 Assembler::~Assembler() {
   if (own_buffer_) {
     if (isolate() != NULL &&
@@ skipping 35 matching lines @@
 }
 
 
 void Assembler::CodeTargetAlign() {
   Align(16);  // Preferred alignment of jump targets on x64.
 }
 
 
 void Assembler::bind_to(Label* L, int pos) {
   ASSERT(!L->is_bound());  // Label may only be bound once.
-  last_pc_ = NULL;
   ASSERT(0 <= pos && pos <= pc_offset());  // Position must be valid.
   if (L->is_linked()) {
     int current = L->pos();
     int next = long_at(current);
     while (next != current) {
       // Relative address, relative to point after address.
       int imm32 = pos - (current + sizeof(int32_t));
       long_at_put(current, imm32);
       current = next;
       next = long_at(next);
     }
     // Fix up last fixup on linked list.
     int last_imm32 = pos - (current + sizeof(int32_t));
     long_at_put(current, last_imm32);
   }
   L->bind_to(pos);
 }
 
 
 void Assembler::bind(Label* L) {
   bind_to(L, pc_offset());
 }
 
 
 void Assembler::bind(NearLabel* L) {
   ASSERT(!L->is_bound());
-  last_pc_ = NULL;
   while (L->unresolved_branches_ > 0) {
     int branch_pos = L->unresolved_positions_[L->unresolved_branches_ - 1];
     int disp = pc_offset() - branch_pos;
     ASSERT(is_int8(disp));
     set_byte_at(branch_pos - sizeof(int8_t), disp);
     L->unresolved_branches_--;
   }
   L->bind_to(pc_offset());
 }
 
@@ skipping 40 matching lines @@
   if (isolate() != NULL &&
       isolate()->assembler_spare_buffer() == NULL &&
       buffer_size_ == kMinimalBufferSize) {
     isolate()->set_assembler_spare_buffer(buffer_);
   } else {
     DeleteArray(buffer_);
   }
   buffer_ = desc.buffer;
   buffer_size_ = desc.buffer_size;
   pc_ += pc_delta;
-  if (last_pc_ != NULL) {
-    last_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) {
       intptr_t* p = reinterpret_cast<intptr_t*>(it.rinfo()->pc());
       if (*p != 0) {  // 0 means uninitialized.
         *p += pc_delta;
@@ skipping 17 matching lines @@
   // Emit the rest of the encoded operand.
   for (unsigned i = 1; i < length; i++) pc_[i] = adr.buf_[i];
   pc_ += length;
 }
 
 
 // Assembler Instruction implementations.
 
 void Assembler::arithmetic_op(byte opcode, Register reg, const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(reg, op);
   emit(opcode);
   emit_operand(reg, op);
 }
 
 
 void Assembler::arithmetic_op(byte opcode, Register reg, Register rm_reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT((opcode & 0xC6) == 2);
   if (rm_reg.low_bits() == 4)  {  // Forces SIB byte.
     // Swap reg and rm_reg and change opcode operand order.
     emit_rex_64(rm_reg, reg);
     emit(opcode ^ 0x02);
     emit_modrm(rm_reg, reg);
   } else {
     emit_rex_64(reg, rm_reg);
     emit(opcode);
     emit_modrm(reg, rm_reg);
   }
 }
 
 
 void Assembler::arithmetic_op_16(byte opcode, Register reg, Register rm_reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT((opcode & 0xC6) == 2);
   if (rm_reg.low_bits() == 4) {  // Forces SIB byte.
     // Swap reg and rm_reg and change opcode operand order.
     emit(0x66);
     emit_optional_rex_32(rm_reg, reg);
     emit(opcode ^ 0x02);
     emit_modrm(rm_reg, reg);
   } else {
     emit(0x66);
     emit_optional_rex_32(reg, rm_reg);
     emit(opcode);
     emit_modrm(reg, rm_reg);
   }
 }
 
 
 void Assembler::arithmetic_op_16(byte opcode,
                                  Register reg,
                                  const Operand& rm_reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(reg, rm_reg);
   emit(opcode);
   emit_operand(reg, rm_reg);
 }
 
 
 void Assembler::arithmetic_op_32(byte opcode, Register reg, Register rm_reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT((opcode & 0xC6) == 2);
   if (rm_reg.low_bits() == 4) {  // Forces SIB byte.
     // Swap reg and rm_reg and change opcode operand order.
     emit_optional_rex_32(rm_reg, reg);
     emit(opcode ^ 0x02);  // E.g. 0x03 -> 0x01 for ADD.
     emit_modrm(rm_reg, reg);
   } else {
     emit_optional_rex_32(reg, rm_reg);
     emit(opcode);
     emit_modrm(reg, rm_reg);
   }
 }
 
 
 void Assembler::arithmetic_op_32(byte opcode,
                                  Register reg,
                                  const Operand& rm_reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(reg, rm_reg);
   emit(opcode);
   emit_operand(reg, rm_reg);
 }
 
 
 void Assembler::immediate_arithmetic_op(byte subcode,
                                         Register dst,
                                         Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_modrm(subcode, dst);
     emit(src.value_);
   } else if (dst.is(rax)) {
     emit(0x05 | (subcode << 3));
     emitl(src.value_);
   } else {
     emit(0x81);
     emit_modrm(subcode, dst);
     emitl(src.value_);
   }
 }
 
 void Assembler::immediate_arithmetic_op(byte subcode,
                                         const Operand& dst,
                                         Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_operand(subcode, dst);
     emit(src.value_);
   } else {
     emit(0x81);
     emit_operand(subcode, dst);
     emitl(src.value_);
   }
 }
 
 
 void Assembler::immediate_arithmetic_op_16(byte subcode,
                                            Register dst,
                                            Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);  // Operand size override prefix.
   emit_optional_rex_32(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_modrm(subcode, dst);
     emit(src.value_);
   } else if (dst.is(rax)) {
     emit(0x05 | (subcode << 3));
     emitw(src.value_);
   } else {
     emit(0x81);
     emit_modrm(subcode, dst);
     emitw(src.value_);
   }
 }
 
 
 void Assembler::immediate_arithmetic_op_16(byte subcode,
                                            const Operand& dst,
                                            Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);  // Operand size override prefix.
   emit_optional_rex_32(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_operand(subcode, dst);
     emit(src.value_);
   } else {
     emit(0x81);
     emit_operand(subcode, dst);
     emitw(src.value_);
   }
 }
 
 
 void Assembler::immediate_arithmetic_op_32(byte subcode,
                                            Register dst,
                                            Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_modrm(subcode, dst);
     emit(src.value_);
   } else if (dst.is(rax)) {
     emit(0x05 | (subcode << 3));
     emitl(src.value_);
   } else {
     emit(0x81);
     emit_modrm(subcode, dst);
     emitl(src.value_);
   }
 }
 
 
 void Assembler::immediate_arithmetic_op_32(byte subcode,
                                            const Operand& dst,
                                            Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   if (is_int8(src.value_)) {
     emit(0x83);
     emit_operand(subcode, dst);
     emit(src.value_);
   } else {
     emit(0x81);
     emit_operand(subcode, dst);
     emitl(src.value_);
   }
 }
 
 
 void Assembler::immediate_arithmetic_op_8(byte subcode,
                                           const Operand& dst,
                                           Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   ASSERT(is_int8(src.value_) || is_uint8(src.value_));
   emit(0x80);
   emit_operand(subcode, dst);
   emit(src.value_);
 }
 
 
 void Assembler::immediate_arithmetic_op_8(byte subcode,
                                           Register dst,
                                           Immediate src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (dst.code() > 3) {
     // Use 64-bit mode byte registers.
     emit_rex_64(dst);
   }
   ASSERT(is_int8(src.value_) || is_uint8(src.value_));
   emit(0x80);
   emit_modrm(subcode, dst);
   emit(src.value_);
 }
 
 
 void Assembler::shift(Register dst, Immediate shift_amount, int subcode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint6(shift_amount.value_));  // illegal shift count
   if (shift_amount.value_ == 1) {
     emit_rex_64(dst);
     emit(0xD1);
     emit_modrm(subcode, dst);
   } else {
     emit_rex_64(dst);
     emit(0xC1);
     emit_modrm(subcode, dst);
     emit(shift_amount.value_);
   }
 }
 
 
 void Assembler::shift(Register dst, int subcode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xD3);
   emit_modrm(subcode, dst);
 }
 
 
 void Assembler::shift_32(Register dst, int subcode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xD3);
   emit_modrm(subcode, dst);
 }
 
 
 void Assembler::shift_32(Register dst, Immediate shift_amount, int subcode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(shift_amount.value_));  // illegal shift count
   if (shift_amount.value_ == 1) {
     emit_optional_rex_32(dst);
     emit(0xD1);
     emit_modrm(subcode, dst);
   } else {
     emit_optional_rex_32(dst);
     emit(0xC1);
     emit_modrm(subcode, dst);
     emit(shift_amount.value_);
   }
 }
 
 
 void Assembler::bt(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0xA3);
   emit_operand(src, dst);
 }
 
 
 void Assembler::bts(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0xAB);
   emit_operand(src, dst);
 }
 
 
 void Assembler::call(Label* L) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // 1110 1000 #32-bit disp.
   emit(0xE8);
   if (L->is_bound()) {
     int offset = L->pos() - pc_offset() - sizeof(int32_t);
     ASSERT(offset <= 0);
     emitl(offset);
   } else if (L->is_linked()) {
     emitl(L->pos());
     L->link_to(pc_offset() - sizeof(int32_t));
   } else {
     ASSERT(L->is_unused());
     int32_t current = pc_offset();
     emitl(current);
     L->link_to(current);
   }
 }
 
 
 void Assembler::call(Handle<Code> target, RelocInfo::Mode rmode) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // 1110 1000 #32-bit disp.
   emit(0xE8);
   emit_code_target(target, rmode);
 }
 
 
 void Assembler::call(Register adr) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: FF /2 r64.
   emit_optional_rex_32(adr);
   emit(0xFF);
   emit_modrm(0x2, adr);
 }
 
 
 void Assembler::call(const Operand& op) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: FF /2 m64.
   emit_optional_rex_32(op);
   emit(0xFF);
   emit_operand(0x2, op);
 }
 
 
 // Calls directly to the given address using a relative offset.
 // Should only ever be used in Code objects for calls within the
 // same Code object. Should not be used when generating new code (use labels),
 // but only when patching existing code.
 void Assembler::call(Address target) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // 1110 1000 #32-bit disp.
   emit(0xE8);
   Address source = pc_ + 4;
   intptr_t displacement = target - source;
   ASSERT(is_int32(displacement));
   emitl(static_cast<int32_t>(displacement));
 }
 
 
 void Assembler::clc() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF8);
 }
 
 void Assembler::cld() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xFC);
 }
 
 void Assembler::cdq() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x99);
 }
 
 
 void Assembler::cmovq(Condition cc, Register dst, Register src) {
   if (cc == always) {
     movq(dst, src);
   } else if (cc == never) {
     return;
   }
   // No need to check CpuInfo for CMOV support, it's a required part of the
   // 64-bit architecture.
   ASSERT(cc >= 0);  // Use mov for unconditional moves.
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: REX.W 0f 40 + cc /r.
   emit_rex_64(dst, src);
   emit(0x0f);
   emit(0x40 + cc);
   emit_modrm(dst, src);
 }
 
 
 void Assembler::cmovq(Condition cc, Register dst, const Operand& src) {
   if (cc == always) {
     movq(dst, src);
   } else if (cc == never) {
     return;
   }
   ASSERT(cc >= 0);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: REX.W 0f 40 + cc /r.
   emit_rex_64(dst, src);
   emit(0x0f);
   emit(0x40 + cc);
   emit_operand(dst, src);
 }
 
 
 void Assembler::cmovl(Condition cc, Register dst, Register src) {
   if (cc == always) {
     movl(dst, src);
   } else if (cc == never) {
     return;
   }
   ASSERT(cc >= 0);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: 0f 40 + cc /r.
   emit_optional_rex_32(dst, src);
   emit(0x0f);
   emit(0x40 + cc);
   emit_modrm(dst, src);
 }
 
 
 void Assembler::cmovl(Condition cc, Register dst, const Operand& src) {
   if (cc == always) {
     movl(dst, src);
   } else if (cc == never) {
     return;
   }
   ASSERT(cc >= 0);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: 0f 40 + cc /r.
   emit_optional_rex_32(dst, src);
   emit(0x0f);
   emit(0x40 + cc);
   emit_operand(dst, src);
 }
 
 
 void Assembler::cmpb_al(Immediate imm8) {
   ASSERT(is_int8(imm8.value_) || is_uint8(imm8.value_));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x3c);
   emit(imm8.value_);
 }
 
 
 void Assembler::cpuid() {
   ASSERT(CpuFeatures::IsEnabled(CPUID));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x0F);
   emit(0xA2);
 }
 
 
 void Assembler::cqo() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64();
   emit(0x99);
 }
 
 
 void Assembler::decq(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xFF);
   emit_modrm(0x1, dst);
 }
 
 
 void Assembler::decq(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xFF);
   emit_operand(1, dst);
 }
 
 
 void Assembler::decl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xFF);
   emit_modrm(0x1, dst);
 }
 
 
 void Assembler::decl(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xFF);
   emit_operand(1, dst);
 }
 
 
 void Assembler::decb(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (dst.code() > 3) {
     // Register is not one of al, bl, cl, dl.  Its encoding needs REX.
     emit_rex_32(dst);
   }
   emit(0xFE);
   emit_modrm(0x1, dst);
 }
 
 
 void Assembler::decb(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xFE);
   emit_operand(1, dst);
 }
 
 
 void Assembler::enter(Immediate size) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xC8);
   emitw(size.value_);  // 16 bit operand, always.
   emit(0);
 }
 
 
 void Assembler::hlt() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF4);
 }
 
 
 void Assembler::idivq(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src);
   emit(0xF7);
   emit_modrm(0x7, src);
 }
 
 
 void Assembler::idivl(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(src);
   emit(0xF7);
   emit_modrm(0x7, src);
 }
 
 
 void Assembler::imul(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src);
   emit(0xF7);
   emit_modrm(0x5, src);
 }
 
 
 void Assembler::imul(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0xAF);
   emit_modrm(dst, src);
 }
 
 
 void Assembler::imul(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0xAF);
   emit_operand(dst, src);
 }
 
 
 void Assembler::imul(Register dst, Register src, Immediate imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   if (is_int8(imm.value_)) {
     emit(0x6B);
     emit_modrm(dst, src);
     emit(imm.value_);
   } else {
     emit(0x69);
     emit_modrm(dst, src);
     emitl(imm.value_);
   }
 }
 
 
 void Assembler::imull(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xAF);
   emit_modrm(dst, src);
 }
 
 
 void Assembler::imull(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xAF);
   emit_operand(dst, src);
 }
 
 
 void Assembler::imull(Register dst, Register src, Immediate imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   if (is_int8(imm.value_)) {
     emit(0x6B);
     emit_modrm(dst, src);
     emit(imm.value_);
   } else {
     emit(0x69);
     emit_modrm(dst, src);
     emitl(imm.value_);
   }
 }
 
 
 void Assembler::incq(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xFF);
   emit_modrm(0x0, dst);
 }
 
 
 void Assembler::incq(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xFF);
   emit_operand(0, dst);
 }
 
 
 void Assembler::incl(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xFF);
   emit_operand(0, dst);
 }
 
 
 void Assembler::incl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xFF);
   emit_modrm(0, dst);
 }
 
 
 void Assembler::int3() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xCC);
 }
 
 
 void Assembler::j(Condition cc, Label* L) {
   if (cc == always) {
     jmp(L);
     return;
   } else if (cc == never) {
     return;
   }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint4(cc));
   if (L->is_bound()) {
     const int short_size = 2;
     const int long_size  = 6;
     int offs = L->pos() - pc_offset();
     ASSERT(offs <= 0);
     if (is_int8(offs - short_size)) {
       // 0111 tttn #8-bit disp.
       emit(0x70 | cc);
       emit((offs - short_size) & 0xFF);
@@ skipping 17 matching lines @@
     emitl(current);
     L->link_to(current);
   }
 }
 
 
 void Assembler::j(Condition cc,
                   Handle<Code> target,
                   RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint4(cc));
   // 0000 1111 1000 tttn #32-bit disp.
   emit(0x0F);
   emit(0x80 | cc);
   emit_code_target(target, rmode);
 }
 
 
 void Assembler::j(Condition cc, NearLabel* L, Hint hint) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(0 <= cc && cc < 16);
   if (FLAG_emit_branch_hints && hint != no_hint) emit(hint);
   if (L->is_bound()) {
     const int short_size = 2;
     int offs = L->pos() - pc_offset();
     ASSERT(offs <= 0);
     ASSERT(is_int8(offs - short_size));
     // 0111 tttn #8-bit disp
     emit(0x70 | cc);
     emit((offs - short_size) & 0xFF);
   } else {
     emit(0x70 | cc);
     emit(0x00);      // The displacement will be resolved later.
     L->link_to(pc_offset());
   }
 }
 
 
 void Assembler::jmp(Label* L) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   const int short_size = sizeof(int8_t);
   const int long_size = sizeof(int32_t);
   if (L->is_bound()) {
     int offs = L->pos() - pc_offset() - 1;
     ASSERT(offs <= 0);
     if (is_int8(offs - short_size)) {
       // 1110 1011 #8-bit disp.
       emit(0xEB);
       emit((offs - short_size) & 0xFF);
     } else {
@@ skipping 12 matching lines @@
     emit(0xE9);
     int32_t current = pc_offset();
     emitl(current);
     L->link_to(current);
   }
 }
 
 
 void Assembler::jmp(Handle<Code> target, RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // 1110 1001 #32-bit disp.
   emit(0xE9);
   emit_code_target(target, rmode);
 }
 
 
 void Assembler::jmp(NearLabel* L) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (L->is_bound()) {
     const int short_size = sizeof(int8_t);
     int offs = L->pos() - pc_offset();
     ASSERT(offs <= 0);
     ASSERT(is_int8(offs - short_size));
     // 1110 1011 #8-bit disp.
     emit(0xEB);
     emit((offs - short_size) & 0xFF);
   } else {
     emit(0xEB);
     emit(0x00);      // The displacement will be resolved later.
     L->link_to(pc_offset());
   }
 }
 
 
 void Assembler::jmp(Register target) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode FF/4 r64.
   emit_optional_rex_32(target);
   emit(0xFF);
   emit_modrm(0x4, target);
 }
 
 
 void Assembler::jmp(const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode FF/4 m64.
   emit_optional_rex_32(src);
   emit(0xFF);
   emit_operand(0x4, src);
 }
 
 
 void Assembler::lea(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x8D);
   emit_operand(dst, src);
 }
 
 
 void Assembler::leal(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x8D);
   emit_operand(dst, src);
 }
 
 
 void Assembler::load_rax(void* value, RelocInfo::Mode mode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x48);  // REX.W
   emit(0xA1);
   emitq(reinterpret_cast<uintptr_t>(value), mode);
 }
 
 
 void Assembler::load_rax(ExternalReference ref) {
   load_rax(ref.address(), RelocInfo::EXTERNAL_REFERENCE);
 }
 
 
 void Assembler::leave() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xC9);
 }
 
 
 void Assembler::movb(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_32(dst, src);
   emit(0x8A);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movb(Register dst, Immediate imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_32(dst);
   emit(0xC6);
   emit_modrm(0x0, dst);
   emit(imm.value_);
 }
 
 
 void Assembler::movb(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_32(src, dst);
   emit(0x88);
   emit_operand(src, dst);
 }
 
 
 void Assembler::movw(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(src, dst);
   emit(0x89);
   emit_operand(src, dst);
 }
 
 
 void Assembler::movl(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x8B);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movl(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.low_bits() == 4) {
     emit_optional_rex_32(src, dst);
     emit(0x89);
     emit_modrm(src, dst);
   } else {
     emit_optional_rex_32(dst, src);
     emit(0x8B);
     emit_modrm(dst, src);
   }
 }
 
 
 void Assembler::movl(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(src, dst);
   emit(0x89);
   emit_operand(src, dst);
 }
 
 
 void Assembler::movl(const Operand& dst, Immediate value) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xC7);
   emit_operand(0x0, dst);
   emit(value);  // Only 32-bit immediates are possible, not 8-bit immediates.
 }
 
 
 void Assembler::movl(Register dst, Immediate value) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xC7);
   emit_modrm(0x0, dst);
   emit(value);  // Only 32-bit immediates are possible, not 8-bit immediates.
 }
 
 
 void Assembler::movq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x8B);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movq(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.low_bits() == 4) {
     emit_rex_64(src, dst);
     emit(0x89);
     emit_modrm(src, dst);
   } else {
     emit_rex_64(dst, src);
     emit(0x8B);
     emit_modrm(dst, src);
   }
 }
 
 
 void Assembler::movq(Register dst, Immediate value) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xC7);
   emit_modrm(0x0, dst);
   emit(value);  // Only 32-bit immediates are possible, not 8-bit immediates.
 }
 
 
 void Assembler::movq(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src, dst);
   emit(0x89);
   emit_operand(src, dst);
 }
 
 
 void Assembler::movq(Register dst, void* value, RelocInfo::Mode rmode) {
   // This method must not be used with heap object references. The stored
   // address is not GC safe. Use the handle version instead.
   ASSERT(rmode > RelocInfo::LAST_GCED_ENUM);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xB8 | dst.low_bits());
   emitq(reinterpret_cast<uintptr_t>(value), rmode);
 }
 
 
 void Assembler::movq(Register dst, int64_t value, RelocInfo::Mode rmode) {
   // Non-relocatable values might not need a 64-bit representation.
   if (rmode == RelocInfo::NONE) {
     // Sadly, there is no zero or sign extending move for 8-bit immediates.
     if (is_int32(value)) {
       movq(dst, Immediate(static_cast<int32_t>(value)));
       return;
     } else if (is_uint32(value)) {
       movl(dst, Immediate(static_cast<int32_t>(value)));
       return;
     }
     // Value cannot be represented by 32 bits, so do a full 64 bit immediate
     // value.
   }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xB8 | dst.low_bits());
   emitq(value, rmode);
 }
 
 
 void Assembler::movq(Register dst, ExternalReference ref) {
   int64_t value = reinterpret_cast<int64_t>(ref.address());
   movq(dst, value, RelocInfo::EXTERNAL_REFERENCE);
 }
 
 
 void Assembler::movq(const Operand& dst, Immediate value) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xC7);
   emit_operand(0, dst);
   emit(value);
 }
 
 
 // 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_;
   emit_optional_rex_32(dst);
   emit(0xC7);
   emit_operand(0, dst);
   if (src->is_bound()) {
     int offset = src->pos() - pc_offset() - sizeof(int32_t);
     ASSERT(offset <= 0);
     emitl(offset);
   } else if (src->is_linked()) {
     emitl(src->pos());
     src->link_to(pc_offset() - sizeof(int32_t));
   } else {
     ASSERT(src->is_unused());
     int32_t current = pc_offset();
     emitl(current);
     src->link_to(current);
   }
 }
 
 
 void Assembler::movq(Register dst, Handle<Object> value, RelocInfo::Mode mode) {
   // If there is no relocation info, emit the value of the handle efficiently
   // (possibly using less that 8 bytes for the value).
   if (mode == RelocInfo::NONE) {
     // There is no possible reason to store a heap pointer without relocation
     // info, so it must be a smi.
     ASSERT(value->IsSmi());
     movq(dst, reinterpret_cast<int64_t>(*value), RelocInfo::NONE);
   } else {
     EnsureSpace ensure_space(this);
-    last_pc_ = pc_;
     ASSERT(value->IsHeapObject());
     ASSERT(!HEAP->InNewSpace(*value));
     emit_rex_64(dst);
     emit(0xB8 | dst.low_bits());
     emitq(reinterpret_cast<uintptr_t>(value.location()), mode);
   }
 }
 
 
 void Assembler::movsxbq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0xBE);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movsxwq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0xBF);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movsxlq(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x63);
   emit_modrm(dst, src);
 }
 
 
 void Assembler::movsxlq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst, src);
   emit(0x63);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movzxbq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xB6);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movzxbl(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xB6);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movzxwq(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xB7);
   emit_operand(dst, src);
 }
 
 
 void Assembler::movzxwl(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0xB7);
   emit_operand(dst, src);
 }
 
 
 void Assembler::repmovsb() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit(0xA4);
 }
 
 
 void Assembler::repmovsw() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);  // Operand size override.
   emit(0xF3);
   emit(0xA4);
 }
 
 
 void Assembler::repmovsl() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit(0xA5);
 }
 
 
 void Assembler::repmovsq() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_rex_64();
   emit(0xA5);
 }
 
 
 void Assembler::mul(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src);
   emit(0xF7);
   emit_modrm(0x4, src);
 }
 
 
 void Assembler::neg(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xF7);
   emit_modrm(0x3, dst);
 }
 
 
 void Assembler::negl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xF7);
   emit_modrm(0x3, dst);
 }
 
 
 void Assembler::neg(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xF7);
   emit_operand(3, dst);
 }
 
 
 void Assembler::nop() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x90);
 }
 
 
 void Assembler::not_(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xF7);
   emit_modrm(0x2, dst);
 }
 
 
 void Assembler::not_(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(dst);
   emit(0xF7);
   emit_operand(2, dst);
 }
 
 
 void Assembler::notl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0xF7);
   emit_modrm(0x2, dst);
 }
 
 
 void Assembler::nop(int n) {
   // The recommended muti-byte sequences of NOP instructions from the Intel 64
   // and IA-32 Architectures Software Developer's Manual.
   //
   // Length   Assembly                                Byte Sequence
   // 2 bytes  66 NOP                                  66 90H
   // 3 bytes  NOP DWORD ptr [EAX]                     0F 1F 00H
   // 4 bytes  NOP DWORD ptr [EAX + 00H]               0F 1F 40 00H
   // 5 bytes  NOP DWORD ptr [EAX + EAX*1 + 00H]       0F 1F 44 00 00H
   // 6 bytes  66 NOP DWORD ptr [EAX + EAX*1 + 00H]    66 0F 1F 44 00 00H
   // 7 bytes  NOP DWORD ptr [EAX + 00000000H]         0F 1F 80 00 00 00 00H
   // 8 bytes  NOP DWORD ptr [EAX + EAX*1 + 00000000H] 0F 1F 84 00 00 00 00 00H
   // 9 bytes  66 NOP DWORD ptr [EAX + EAX*1 +         66 0F 1F 84 00 00 00 00
   //          00000000H]                              00H
 
   ASSERT(1 <= n);
   ASSERT(n <= 9);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   switch (n) {
   case 1:
     emit(0x90);
     return;
   case 2:
     emit(0x66);
     emit(0x90);
     return;
   case 3:
     emit(0x0f);
@@ skipping 50 matching lines @@
     emit(0x00);
     emit(0x00);
     emit(0x00);
     return;
   }
 }
 
 
 void Assembler::pop(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0x58 | dst.low_bits());
 }
 
 
 void Assembler::pop(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(dst);
   emit(0x8F);
   emit_operand(0, dst);
 }
 
 
 void Assembler::popfq() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x9D);
 }
 
 
 void Assembler::push(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(src);
   emit(0x50 | src.low_bits());
 }
 
 
 void Assembler::push(const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(src);
   emit(0xFF);
   emit_operand(6, src);
 }
 
 
 void Assembler::push(Immediate value) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (is_int8(value.value_)) {
     emit(0x6A);
     emit(value.value_);  // Emit low byte of value.
   } else {
     emit(0x68);
     emitl(value.value_);
   }
 }
 
 
 void Assembler::push_imm32(int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x68);
   emitl(imm32);
 }
 
 
 void Assembler::pushfq() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x9C);
 }
 
 
 void Assembler::rdtsc() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x0F);
   emit(0x31);
 }
 
 
 void Assembler::ret(int imm16) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint16(imm16));
   if (imm16 == 0) {
     emit(0xC3);
   } else {
     emit(0xC2);
     emit(imm16 & 0xFF);
     emit((imm16 >> 8) & 0xFF);
   }
 }
 
 
 void Assembler::setcc(Condition cc, Register reg) {
   if (cc > last_condition) {
     movb(reg, Immediate(cc == always ? 1 : 0));
     return;
   }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint4(cc));
   if (reg.code() > 3) {  // Use x64 byte registers, where different.
     emit_rex_32(reg);
   }
   emit(0x0F);
   emit(0x90 | cc);
   emit_modrm(0x0, reg);
 }
 
 
 void Assembler::shld(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0xA5);
   emit_modrm(src, dst);
 }
 
 
 void Assembler::shrd(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0xAD);
   emit_modrm(src, dst);
 }
 
 
 void Assembler::xchg(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.is(rax) || dst.is(rax)) {  // Single-byte encoding
     Register other = src.is(rax) ? dst : src;
     emit_rex_64(other);
     emit(0x90 | other.low_bits());
   } else if (dst.low_bits() == 4) {
     emit_rex_64(dst, src);
     emit(0x87);
     emit_modrm(dst, src);
   } else {
     emit_rex_64(src, dst);
     emit(0x87);
     emit_modrm(src, dst);
   }
 }
 
 
 void Assembler::store_rax(void* dst, RelocInfo::Mode mode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x48);  // REX.W
   emit(0xA3);
   emitq(reinterpret_cast<uintptr_t>(dst), mode);
 }
 
 
 void Assembler::store_rax(ExternalReference ref) {
   store_rax(ref.address(), RelocInfo::EXTERNAL_REFERENCE);
 }
 
 
 void Assembler::testb(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.low_bits() == 4) {
     emit_rex_32(src, dst);
     emit(0x84);
     emit_modrm(src, dst);
   } else {
     if (dst.code() > 3 || src.code() > 3) {
       // Register is not one of al, bl, cl, dl.  Its encoding needs REX.
       emit_rex_32(dst, src);
     }
     emit(0x84);
     emit_modrm(dst, src);
   }
 }
 
 
 void Assembler::testb(Register reg, Immediate mask) {
   ASSERT(is_int8(mask.value_) || is_uint8(mask.value_));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (reg.is(rax)) {
     emit(0xA8);
     emit(mask.value_);  // Low byte emitted.
   } else {
     if (reg.code() > 3) {
       // Register is not one of al, bl, cl, dl.  Its encoding needs REX.
       emit_rex_32(reg);
     }
     emit(0xF6);
     emit_modrm(0x0, reg);
     emit(mask.value_);  // Low byte emitted.
   }
 }
 
 
 void Assembler::testb(const Operand& op, Immediate mask) {
   ASSERT(is_int8(mask.value_) || is_uint8(mask.value_));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(rax, op);
   emit(0xF6);
   emit_operand(rax, op);  // Operation code 0
   emit(mask.value_);  // Low byte emitted.
 }
 
 
 void Assembler::testb(const Operand& op, Register reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (reg.code() > 3) {
     // Register is not one of al, bl, cl, dl.  Its encoding needs REX.
     emit_rex_32(reg, op);
   } else {
     emit_optional_rex_32(reg, op);
   }
   emit(0x84);
   emit_operand(reg, op);
 }
 
 
 void Assembler::testl(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.low_bits() == 4) {
     emit_optional_rex_32(src, dst);
     emit(0x85);
     emit_modrm(src, dst);
   } else {
     emit_optional_rex_32(dst, src);
     emit(0x85);
     emit_modrm(dst, src);
   }
 }
 
 
 void Assembler::testl(Register reg, Immediate mask) {
   // testl with a mask that fits in the low byte is exactly testb.
   if (is_uint8(mask.value_)) {
     testb(reg, mask);
     return;
   }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (reg.is(rax)) {
     emit(0xA9);
     emit(mask);
   } else {
     emit_optional_rex_32(rax, reg);
     emit(0xF7);
     emit_modrm(0x0, reg);
     emit(mask);
   }
 }
 
 
 void Assembler::testl(const Operand& op, Immediate mask) {
   // testl with a mask that fits in the low byte is exactly testb.
   if (is_uint8(mask.value_)) {
     testb(op, mask);
     return;
   }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(rax, op);
   emit(0xF7);
   emit_operand(rax, op);  // Operation code 0
   emit(mask);
 }
 
 
 void Assembler::testq(const Operand& op, Register reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_rex_64(reg, op);
   emit(0x85);
   emit_operand(reg, op);
 }
 
 
 void Assembler::testq(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.low_bits() == 4) {
     emit_rex_64(src, dst);
     emit(0x85);
     emit_modrm(src, dst);
   } else {
     emit_rex_64(dst, src);
     emit(0x85);
     emit_modrm(dst, src);
   }
 }
 
 
 void Assembler::testq(Register dst, Immediate mask) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (dst.is(rax)) {
     emit_rex_64();
     emit(0xA9);
     emit(mask);
   } else {
     emit_rex_64(dst);
     emit(0xF7);
     emit_modrm(0, dst);
     emit(mask);
   }
 }
 
 
 // FPU instructions.
 
 
 void Assembler::fld(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xD9, 0xC0, i);
 }
 
 
 void Assembler::fld1() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xE8);
 }
 
 
 void Assembler::fldz() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xEE);
 }
 
 
 void Assembler::fldpi() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xEB);
 }
 
 
 void Assembler::fldln2() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xED);
 }
 
 
 void Assembler::fld_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xD9);
   emit_operand(0, adr);
 }
 
 
 void Assembler::fld_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDD);
   emit_operand(0, adr);
 }
 
 
 void Assembler::fstp_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xD9);
   emit_operand(3, adr);
 }
 
 
 void Assembler::fstp_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDD);
   emit_operand(3, adr);
 }
 
 
 void Assembler::fstp(int index) {
   ASSERT(is_uint3(index));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDD, 0xD8, index);
 }
 
 
 void Assembler::fild_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDB);
   emit_operand(0, adr);
 }
 
 
 void Assembler::fild_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDF);
   emit_operand(5, adr);
 }
 
 
 void Assembler::fistp_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDB);
   emit_operand(3, adr);
 }
 
 
 void Assembler::fisttp_s(const Operand& adr) {
   ASSERT(CpuFeatures::IsEnabled(SSE3));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDB);
   emit_operand(1, adr);
 }
 
 
 void Assembler::fisttp_d(const Operand& adr) {
   ASSERT(CpuFeatures::IsEnabled(SSE3));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDD);
   emit_operand(1, adr);
 }
 
 
 void Assembler::fist_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDB);
   emit_operand(2, adr);
 }
 
 
 void Assembler::fistp_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDF);
   emit_operand(7, adr);
 }
 
 
 void Assembler::fabs() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xE1);
 }
 
 
 void Assembler::fchs() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xE0);
 }
 
 
 void Assembler::fcos() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xFF);
 }
 
 
 void Assembler::fsin() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xFE);
 }
 
 
 void Assembler::fyl2x() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xF1);
 }
 
 
 void Assembler::fadd(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDC, 0xC0, i);
 }
 
 
 void Assembler::fsub(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDC, 0xE8, i);
 }
 
 
 void Assembler::fisub_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_optional_rex_32(adr);
   emit(0xDA);
   emit_operand(4, adr);
 }
 
 
 void Assembler::fmul(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDC, 0xC8, i);
 }
 
 
 void Assembler::fdiv(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDC, 0xF8, i);
 }
 
 
 void Assembler::faddp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDE, 0xC0, i);
 }
 
 
 void Assembler::fsubp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDE, 0xE8, i);
 }
 
 
 void Assembler::fsubrp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDE, 0xE0, i);
 }
 
 
 void Assembler::fmulp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDE, 0xC8, i);
 }
 
 
 void Assembler::fdivp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDE, 0xF8, i);
 }
 
 
 void Assembler::fprem() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xF8);
 }
 
 
 void Assembler::fprem1() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xF5);
 }
 
 
 void Assembler::fxch(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xD9, 0xC8, i);
 }
 
 
 void Assembler::fincstp() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xF7);
 }
 
 
 void Assembler::ffree(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDD, 0xC0, i);
 }
 
 
 void Assembler::ftst() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xE4);
 }
 
 
 void Assembler::fucomp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDD, 0xE8, i);
 }
 
 
 void Assembler::fucompp() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDA);
   emit(0xE9);
 }
 
 
 void Assembler::fucomi(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDB);
   emit(0xE8 + i);
 }
 
 
 void Assembler::fucomip() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDF);
   emit(0xE9);
 }
 
 
 void Assembler::fcompp() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDE);
   emit(0xD9);
 }
 
 
 void Assembler::fnstsw_ax() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDF);
   emit(0xE0);
 }
 
 
 void Assembler::fwait() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x9B);
 }
 
 
 void Assembler::frndint() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xD9);
   emit(0xFC);
 }
 
 
 void Assembler::fnclex() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xDB);
   emit(0xE2);
 }
 
 
 void Assembler::sahf() {
   // TODO(X64): Test for presence. Not all 64-bit intel CPU's have sahf
   // in 64-bit mode. Test CpuID.
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x9E);
 }
 
 
 void Assembler::emit_farith(int b1, int b2, int i) {
   ASSERT(is_uint8(b1) && is_uint8(b2));  // wrong opcode
   ASSERT(is_uint3(i));  // illegal stack offset
   emit(b1);
   emit(b2 + i);
 }
 
 // SSE 2 operations.
 
 void Assembler::movd(XMMRegister dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x6E);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movd(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(src, dst);
   emit(0x0F);
   emit(0x7E);
   emit_sse_operand(src, dst);
 }
 
 
 void Assembler::movq(XMMRegister dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0x6E);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movq(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0x7E);
   emit_sse_operand(src, dst);
 }
 
 
 void Assembler::movdqa(const Operand& dst, XMMRegister src) {
-  ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_rex_64(src, dst);
   emit(0x0F);
   emit(0x7F);
   emit_sse_operand(src, dst);
 }
 
 
 void Assembler::movdqa(XMMRegister dst, const Operand& src) {
-  ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0x6F);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::extractps(Register dst, XMMRegister src, byte imm8) {
   ASSERT(is_uint2(imm8));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x3A);
   emit(0x17);
   emit_sse_operand(dst, src);
   emit(imm8);
 }
 
 
 void Assembler::movsd(const Operand& dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);  // double
   emit_optional_rex_32(src, dst);
   emit(0x0F);
   emit(0x11);  // store
   emit_sse_operand(src, dst);
 }
 
 
 void Assembler::movsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);  // double
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x10);  // load
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movsd(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);  // double
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x10);  // load
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movss(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);  // single
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x10);  // load
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movss(const Operand& src, XMMRegister dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);  // single
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x11);  // store
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvttss2si(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2C);
   emit_operand(dst, src);
 }
 
 
 void Assembler::cvttss2si(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2C);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvttsd2si(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2C);
   emit_operand(dst, src);
 }
 
 
 void Assembler::cvttsd2si(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2C);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvttsd2siq(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0x2C);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtlsi2sd(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtlsi2sd(XMMRegister dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtlsi2ss(XMMRegister dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtqsi2sd(XMMRegister dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0x2A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtss2sd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x5A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtss2sd(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF3);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x5A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtsd2ss(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x5A);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtsd2si(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x2D);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::cvtsd2siq(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_rex_64(dst, src);
   emit(0x0F);
   emit(0x2D);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::addsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x58);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::mulsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x59);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::subsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x5C);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::divsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x5E);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::andpd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x54);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::orpd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x56);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::xorpd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x57);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::sqrtsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0xF2);
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x51);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::ucomisd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0f);
   emit(0x2e);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::ucomisd(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0f);
   emit(0x2e);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::movmskpd(Register dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit(0x66);
   emit_optional_rex_32(dst, src);
   emit(0x0f);
   emit(0x50);
   emit_sse_operand(dst, src);
 }
 
 
 void Assembler::emit_sse_operand(XMMRegister reg, const Operand& adr) {
   Register ireg = { reg.code() };
@@ skipping 76 matching lines @@
   // specially coded on x64 means that it is a relative 32 bit address, as used
   // by branch instructions.
   return (1 << rmode_) & kApplyMask;
 }
 
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64