Remove peephole optimiziations from IA32 and ARM assembler.

They are not used with Crankshaft anymore.
Review URL: http://codereview.chromium.org/7003025

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7854 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/assembler-arm.cc b/src/arm/assembler-arm.cc
index 3533dfd..c7050a7 100644 (file)
--- a/src/arm/assembler-arm.cc
+++ b/src/arm/assembler-arm.cc
@@ -289,9 +289,7 @@ static const int kMinimalBufferSize = 4*KB;
 Assembler::Assembler(Isolate* arg_isolate, void* buffer, int buffer_size)
     : AssemblerBase(arg_isolate),
       positions_recorder_(this),
-      allow_peephole_optimization_(false),
       emit_debug_code_(FLAG_debug_code) {
-  allow_peephole_optimization_ = FLAG_peephole_optimization;
   if (buffer == NULL) {
     // Do our own buffer management.
     if (buffer_size <= kMinimalBufferSize) {
@@ -1096,20 +1094,6 @@ void Assembler::rsb(Register dst, Register src1, const Operand& src2,
 void Assembler::add(Register dst, Register src1, const Operand& src2,
                     SBit s, Condition cond) {
   addrmod1(cond | ADD | s, src1, dst, src2);
-
-  // Eliminate pattern: push(r), pop()
-  //   str(src, MemOperand(sp, 4, NegPreIndex), al);
-  //   add(sp, sp, Operand(kPointerSize));
-  // Both instructions can be eliminated.
-  if (can_peephole_optimize(2) &&
-      // Pattern.
-      instr_at(pc_ - 1 * kInstrSize) == kPopInstruction &&
-      (instr_at(pc_ - 2 * kInstrSize) & ~kRdMask) == kPushRegPattern) {
-    pc_ -= 2 * kInstrSize;
-    if (FLAG_print_peephole_optimization) {
-      PrintF("%x push(reg)/pop() eliminated\n", pc_offset());
-    }
-  }
 }
 
 
@@ -1414,195 +1398,11 @@ void Assembler::ldr(Register dst, const MemOperand& src, Condition cond) {
     positions_recorder()->WriteRecordedPositions();
   }
   addrmod2(cond | B26 | L, dst, src);
-
-  // Eliminate pattern: push(ry), pop(rx)
-  //   str(ry, MemOperand(sp, 4, NegPreIndex), al)
-  //   ldr(rx, MemOperand(sp, 4, PostIndex), al)
-  // Both instructions can be eliminated if ry = rx.
-  // If ry != rx, a register copy from ry to rx is inserted
-  // after eliminating the push and the pop instructions.
-  if (can_peephole_optimize(2)) {
-    Instr push_instr = instr_at(pc_ - 2 * kInstrSize);
-    Instr pop_instr = instr_at(pc_ - 1 * kInstrSize);
-
-    if (IsPush(push_instr) && IsPop(pop_instr)) {
-      if (Instruction::RdValue(pop_instr) != Instruction::RdValue(push_instr)) {
-        // For consecutive push and pop on different registers,
-        // we delete both the push & pop and insert a register move.
-        // push ry, pop rx --> mov rx, ry
-        Register reg_pushed, reg_popped;
-        reg_pushed = GetRd(push_instr);
-        reg_popped = GetRd(pop_instr);
-        pc_ -= 2 * kInstrSize;
-        // Insert a mov instruction, which is better than a pair of push & pop
-        mov(reg_popped, reg_pushed);
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%x push/pop (diff reg) replaced by a reg move\n",
-                 pc_offset());
-        }
-      } else {
-        // For consecutive push and pop on the same register,
-        // both the push and the pop can be deleted.
-        pc_ -= 2 * kInstrSize;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%x push/pop (same reg) eliminated\n", pc_offset());
-        }
-      }
-    }
-  }
-
-  if (can_peephole_optimize(2)) {
-    Instr str_instr = instr_at(pc_ - 2 * kInstrSize);
-    Instr ldr_instr = instr_at(pc_ - 1 * kInstrSize);
-
-    if ((IsStrRegFpOffset(str_instr) &&
-         IsLdrRegFpOffset(ldr_instr)) ||
-       (IsStrRegFpNegOffset(str_instr) &&
-         IsLdrRegFpNegOffset(ldr_instr))) {
-      if ((ldr_instr & kLdrStrInstrArgumentMask) ==
-            (str_instr & kLdrStrInstrArgumentMask)) {
-        // Pattern: Ldr/str same fp+offset, same register.
-        //
-        // The following:
-        // str rx, [fp, #-12]
-        // ldr rx, [fp, #-12]
-        //
-        // Becomes:
-        // str rx, [fp, #-12]
-
-        pc_ -= 1 * kInstrSize;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%x str/ldr (fp + same offset), same reg\n", pc_offset());
-        }
-      } else if ((ldr_instr & kLdrStrOffsetMask) ==
-                 (str_instr & kLdrStrOffsetMask)) {
-        // Pattern: Ldr/str same fp+offset, different register.
-        //
-        // The following:
-        // str rx, [fp, #-12]
-        // ldr ry, [fp, #-12]
-        //
-        // Becomes:
-        // str rx, [fp, #-12]
-        // mov ry, rx
-
-        Register reg_stored, reg_loaded;
-        reg_stored = GetRd(str_instr);
-        reg_loaded = GetRd(ldr_instr);
-        pc_ -= 1 * kInstrSize;
-        // Insert a mov instruction, which is better than ldr.
-        mov(reg_loaded, reg_stored);
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%x str/ldr (fp + same offset), diff reg \n", pc_offset());
-        }
-      }
-    }
-  }
-
-  if (can_peephole_optimize(3)) {
-    Instr mem_write_instr = instr_at(pc_ - 3 * kInstrSize);
-    Instr ldr_instr = instr_at(pc_ - 2 * kInstrSize);
-    Instr mem_read_instr = instr_at(pc_ - 1 * kInstrSize);
-    if (IsPush(mem_write_instr) &&
-        IsPop(mem_read_instr)) {
-      if ((IsLdrRegFpOffset(ldr_instr) ||
-        IsLdrRegFpNegOffset(ldr_instr))) {
-        if (Instruction::RdValue(mem_write_instr) ==
-                                  Instruction::RdValue(mem_read_instr)) {
-          // Pattern: push & pop from/to same register,
-          // with a fp+offset ldr in between
-          //
-          // The following:
-          // str rx, [sp, #-4]!
-          // ldr rz, [fp, #-24]
-          // ldr rx, [sp], #+4
-          //
-          // Becomes:
-          // if(rx == rz)
-          //   delete all
-          // else
-          //   ldr rz, [fp, #-24]
-
-          if (Instruction::RdValue(mem_write_instr) ==
-              Instruction::RdValue(ldr_instr)) {
-            pc_ -= 3 * kInstrSize;
-          } else {
-            pc_ -= 3 * kInstrSize;
-            // Reinsert back the ldr rz.
-            emit(ldr_instr);
-          }
-          if (FLAG_print_peephole_optimization) {
-            PrintF("%x push/pop -dead ldr fp+offset in middle\n", pc_offset());
-          }
-        } else {
-          // Pattern: push & pop from/to different registers
-          // with a fp+offset ldr in between
-          //
-          // The following:
-          // str rx, [sp, #-4]!
-          // ldr rz, [fp, #-24]
-          // ldr ry, [sp], #+4
-          //
-          // Becomes:
-          // if(ry == rz)
-          //   mov ry, rx;
-          // else if(rx != rz)
-          //   ldr rz, [fp, #-24]
-          //   mov ry, rx
-          // else if((ry != rz) || (rx == rz)) becomes:
-          //   mov ry, rx
-          //   ldr rz, [fp, #-24]
-
-          Register reg_pushed, reg_popped;
-          if (Instruction::RdValue(mem_read_instr) ==
-              Instruction::RdValue(ldr_instr)) {
-            reg_pushed = GetRd(mem_write_instr);
-            reg_popped = GetRd(mem_read_instr);
-            pc_ -= 3 * kInstrSize;
-            mov(reg_popped, reg_pushed);
-          } else if (Instruction::RdValue(mem_write_instr) !=
-                     Instruction::RdValue(ldr_instr)) {
-            reg_pushed = GetRd(mem_write_instr);
-            reg_popped = GetRd(mem_read_instr);
-            pc_ -= 3 * kInstrSize;
-            emit(ldr_instr);
-            mov(reg_popped, reg_pushed);
-          } else if ((Instruction::RdValue(mem_read_instr) !=
-                      Instruction::RdValue(ldr_instr)) ||
-                     (Instruction::RdValue(mem_write_instr) ==
-                      Instruction::RdValue(ldr_instr))) {
-            reg_pushed = GetRd(mem_write_instr);
-            reg_popped = GetRd(mem_read_instr);
-            pc_ -= 3 * kInstrSize;
-            mov(reg_popped, reg_pushed);
-            emit(ldr_instr);
-          }
-          if (FLAG_print_peephole_optimization) {
-            PrintF("%x push/pop (ldr fp+off in middle)\n", pc_offset());
-          }
-        }
-      }
-    }
-  }
 }
 
 
 void Assembler::str(Register src, const MemOperand& dst, Condition cond) {
   addrmod2(cond | B26, src, dst);
-
-  // Eliminate pattern: pop(), push(r)
-  //     add sp, sp, #4 LeaveCC, al; str r, [sp, #-4], al
-  // ->  str r, [sp, 0], al
-  if (can_peephole_optimize(2) &&
-     // Pattern.
-     instr_at(pc_ - 1 * kInstrSize) == (kPushRegPattern | src.code() * B12) &&
-     instr_at(pc_ - 2 * kInstrSize) == kPopInstruction) {
-    pc_ -= 2 * kInstrSize;
-    emit(al | B26 | 0 | Offset | sp.code() * B16 | src.code() * B12);
-    if (FLAG_print_peephole_optimization) {
-      PrintF("%x pop()/push(reg) eliminated\n", pc_offset());
-    }
-  }
 }
 
 

diff --git a/src/arm/assembler-arm.h b/src/arm/assembler-arm.h
index c80014b..e1978fb 100644 (file)
--- a/src/arm/assembler-arm.h
+++ b/src/arm/assembler-arm.h
@@ -1186,12 +1186,6 @@ class Assembler : public AssemblerBase {
 
   PositionsRecorder* positions_recorder() { return &positions_recorder_; }
 
-  bool can_peephole_optimize(int instructions) {
-    if (!allow_peephole_optimization_) return false;
-    if (last_bound_pos_ > pc_offset() - instructions * kInstrSize) return false;
-    return reloc_info_writer.last_pc() <= pc_ - instructions * kInstrSize;
-  }
-
   // Read/patch instructions
   static Instr instr_at(byte* pc) { return *reinterpret_cast<Instr*>(pc); }
   static void instr_at_put(byte* pc, Instr instr) {
@@ -1362,7 +1356,6 @@ class Assembler : public AssemblerBase {
   friend class BlockConstPoolScope;
 
   PositionsRecorder positions_recorder_;
-  bool allow_peephole_optimization_;
   bool emit_debug_code_;
   friend class PositionsRecorder;
   friend class EnsureSpace;

diff --git a/src/ia32/assembler-ia32.cc b/src/ia32/assembler-ia32.cc
index 797008e..74cbe46 100644 (file)
--- a/src/ia32/assembler-ia32.cc
+++ b/src/ia32/assembler-ia32.cc
@@ -341,7 +341,6 @@ Assembler::Assembler(Isolate* arg_isolate, void* buffer, int buffer_size)
   pc_ = buffer_;
   reloc_info_writer.Reposition(buffer_ + buffer_size, pc_);
 
-  last_pc_ = NULL;
 #ifdef GENERATED_CODE_COVERAGE
   InitCoverageLog();
 #endif
@@ -389,7 +388,6 @@ void Assembler::CodeTargetAlign() {
 void Assembler::cpuid() {
   ASSERT(CpuFeatures::IsEnabled(CPUID));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xA2);
 }
@@ -397,35 +395,30 @@ void Assembler::cpuid() {
 
 void Assembler::pushad() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x60);
 }
 
 
 void Assembler::popad() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x61);
 }
 
 
 void Assembler::pushfd() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x9C);
 }
 
 
 void Assembler::popfd() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x9D);
 }
 
 
 void Assembler::push(const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (x.is_int8()) {
     EMIT(0x6a);
     EMIT(x.x_);
@@ -445,14 +438,12 @@ void Assembler::push_imm32(int32_t imm32) {
 
 void Assembler::push(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x50 | src.code());
 }
 
 
 void Assembler::push(const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFF);
   emit_operand(esi, src);
 }
@@ -460,125 +451,13 @@ void Assembler::push(const Operand& src) {
 
 void Assembler::pop(Register dst) {
   ASSERT(reloc_info_writer.last_pc() != NULL);
-  if (FLAG_peephole_optimization && (reloc_info_writer.last_pc() <= last_pc_)) {
-    // (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.
-    byte instr = last_pc_[0];
-    if ((instr & ~0x7) == 0x50) {
-      int push_reg_code = instr & 0x7;
-      if (push_reg_code == dst.code()) {
-        pc_ = last_pc_;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (same reg) eliminated\n", pc_offset());
-        }
-      } else {
-        // Convert 'push src; pop dst' to 'mov dst, src'.
-        last_pc_[0] = 0x8b;
-        Register src = { push_reg_code };
-        EnsureSpace ensure_space(this);
-        emit_operand(dst, Operand(src));
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (reg->reg) eliminated\n", pc_offset());
-        }
-      }
-      last_pc_ = NULL;
-      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.
-      if ((op1 & 0x38) == (6 << 3)) {
-        op1 = (op1 & ~0x38) | static_cast<byte>(dst.code() << 3);
-        last_pc_[0] = 0x8b;
-        last_pc_[1] = op1;
-        last_pc_ = NULL;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (op->reg) eliminated\n", pc_offset());
-        }
-        return;
-      }
-    } else if ((instr == 0x89) &&
-               (last_pc_[1] == 0x04) &&
-               (last_pc_[2] == 0x24)) {
-      // 0x71283c   396  890424         mov [esp],eax
-      // 0x71283f   399  58             pop eax
-      if (dst.is(eax)) {
-        // change to
-        // 0x710fac   216  83c404         add esp,0x4
-        last_pc_[0] = 0x83;
-        last_pc_[1] = 0xc4;
-        last_pc_[2] = 0x04;
-        last_pc_ = NULL;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (mov-pop) eliminated\n", pc_offset());
-        }
-        return;
-      }
-    } else if (instr == 0x6a && dst.is(eax)) {  // push of immediate 8 bit
-      byte imm8 = last_pc_[1];
-      if (imm8 == 0) {
-        // 6a00         push 0x0
-        // 58           pop eax
-        last_pc_[0] = 0x31;
-        last_pc_[1] = 0xc0;
-        // change to
-        // 31c0         xor eax,eax
-        last_pc_ = NULL;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (imm->reg) eliminated\n", pc_offset());
-        }
-        return;
-      } else {
-        // 6a00         push 0xXX
-        // 58           pop eax
-        last_pc_[0] = 0xb8;
-        EnsureSpace ensure_space(this);
-        if ((imm8 & 0x80) != 0) {
-          EMIT(0xff);
-          EMIT(0xff);
-          EMIT(0xff);
-          // change to
-          // b8XXffffff   mov eax,0xffffffXX
-        } else {
-          EMIT(0x00);
-          EMIT(0x00);
-          EMIT(0x00);
-          // change to
-          // b8XX000000   mov eax,0x000000XX
-        }
-        last_pc_ = NULL;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop (imm->reg) eliminated\n", pc_offset());
-        }
-        return;
-      }
-    } else if (instr == 0x68 && dst.is(eax)) {  // push of immediate 32 bit
-      // 68XXXXXXXX   push 0xXXXXXXXX
-      // 58           pop eax
-      last_pc_[0] = 0xb8;
-      last_pc_ = NULL;
-      // change to
-      // b8XXXXXXXX   mov eax,0xXXXXXXXX
-      if (FLAG_print_peephole_optimization) {
-        PrintF("%d push/pop (imm->reg) eliminated\n", pc_offset());
-      }
-      return;
-    }
-
-    // Other potential patterns for peephole:
-    // 0x712716   102  890424         mov [esp], eax
-    // 0x712719   105  8b1424         mov edx, [esp]
-  }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x58 | dst.code());
 }
 
 
 void Assembler::pop(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x8F);
   emit_operand(eax, dst);
 }
@@ -586,7 +465,6 @@ void Assembler::pop(const Operand& dst) {
 
 void Assembler::enter(const Immediate& size) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xC8);
   emit_w(size);
   EMIT(0);
@@ -595,7 +473,6 @@ void Assembler::enter(const Immediate& size) {
 
 void Assembler::leave() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xC9);
 }
 
@@ -603,7 +480,6 @@ void Assembler::leave() {
 void Assembler::mov_b(Register dst, const Operand& src) {
   ASSERT(dst.code() < 4);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x8A);
   emit_operand(dst, src);
 }
@@ -611,7 +487,6 @@ void Assembler::mov_b(Register dst, const Operand& src) {
 
 void Assembler::mov_b(const Operand& dst, int8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xC6);
   emit_operand(eax, dst);
   EMIT(imm8);
@@ -621,7 +496,6 @@ void Assembler::mov_b(const Operand& dst, int8_t imm8) {
 void Assembler::mov_b(const Operand& dst, Register src) {
   ASSERT(src.code() < 4);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x88);
   emit_operand(src, dst);
 }
@@ -629,7 +503,6 @@ void Assembler::mov_b(const Operand& dst, Register src) {
 
 void Assembler::mov_w(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x8B);
   emit_operand(dst, src);
@@ -638,7 +511,6 @@ void Assembler::mov_w(Register dst, const Operand& src) {
 
 void Assembler::mov_w(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x89);
   emit_operand(src, dst);
@@ -647,7 +519,6 @@ void Assembler::mov_w(const Operand& dst, Register src) {
 
 void Assembler::mov(Register dst, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xB8 | dst.code());
   emit(imm32);
 }
@@ -655,7 +526,6 @@ void Assembler::mov(Register dst, int32_t imm32) {
 
 void Assembler::mov(Register dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xB8 | dst.code());
   emit(x);
 }
@@ -663,7 +533,6 @@ void Assembler::mov(Register dst, const Immediate& x) {
 
 void Assembler::mov(Register dst, Handle<Object> handle) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xB8 | dst.code());
   emit(handle);
 }
@@ -671,7 +540,6 @@ void Assembler::mov(Register dst, Handle<Object> handle) {
 
 void Assembler::mov(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x8B);
   emit_operand(dst, src);
 }
@@ -679,7 +547,6 @@ void Assembler::mov(Register dst, const Operand& src) {
 
 void Assembler::mov(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x89);
   EMIT(0xC0 | src.code() << 3 | dst.code());
 }
@@ -687,7 +554,6 @@ void Assembler::mov(Register dst, Register src) {
 
 void Assembler::mov(const Operand& dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xC7);
   emit_operand(eax, dst);
   emit(x);
@@ -696,7 +562,6 @@ void Assembler::mov(const Operand& dst, const Immediate& x) {
 
 void Assembler::mov(const Operand& dst, Handle<Object> handle) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xC7);
   emit_operand(eax, dst);
   emit(handle);
@@ -705,7 +570,6 @@ void Assembler::mov(const Operand& dst, Handle<Object> handle) {
 
 void Assembler::mov(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x89);
   emit_operand(src, dst);
 }
@@ -713,7 +577,6 @@ void Assembler::mov(const Operand& dst, Register src) {
 
 void Assembler::movsx_b(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xBE);
   emit_operand(dst, src);
@@ -722,7 +585,6 @@ void Assembler::movsx_b(Register dst, const Operand& src) {
 
 void Assembler::movsx_w(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xBF);
   emit_operand(dst, src);
@@ -731,7 +593,6 @@ void Assembler::movsx_w(Register dst, const Operand& src) {
 
 void Assembler::movzx_b(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xB6);
   emit_operand(dst, src);
@@ -740,7 +601,6 @@ void Assembler::movzx_b(Register dst, const Operand& src) {
 
 void Assembler::movzx_w(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xB7);
   emit_operand(dst, src);
@@ -750,7 +610,6 @@ void Assembler::movzx_w(Register dst, const Operand& src) {
 void Assembler::cmov(Condition cc, Register dst, int32_t imm32) {
   ASSERT(CpuFeatures::IsEnabled(CMOV));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   UNIMPLEMENTED();
   USE(cc);
   USE(dst);
@@ -761,7 +620,6 @@ void Assembler::cmov(Condition cc, Register dst, int32_t imm32) {
 void Assembler::cmov(Condition cc, Register dst, Handle<Object> handle) {
   ASSERT(CpuFeatures::IsEnabled(CMOV));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   UNIMPLEMENTED();
   USE(cc);
   USE(dst);
@@ -772,7 +630,6 @@ void Assembler::cmov(Condition cc, Register dst, Handle<Object> handle) {
 void Assembler::cmov(Condition cc, Register dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(CMOV));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Opcode: 0f 40 + cc /r.
   EMIT(0x0F);
   EMIT(0x40 + cc);
@@ -782,14 +639,12 @@ void Assembler::cmov(Condition cc, Register dst, const Operand& src) {
 
 void Assembler::cld() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFC);
 }
 
 
 void Assembler::rep_movs() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0xA5);
 }
@@ -797,7 +652,6 @@ void Assembler::rep_movs() {
 
 void Assembler::rep_stos() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0xAB);
 }
@@ -805,14 +659,12 @@ void Assembler::rep_stos() {
 
 void Assembler::stos() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xAB);
 }
 
 
 void Assembler::xchg(Register dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (src.is(eax) || dst.is(eax)) {  // Single-byte encoding.
     EMIT(0x90 | (src.is(eax) ? dst.code() : src.code()));
   } else {
@@ -824,14 +676,12 @@ void Assembler::xchg(Register dst, Register src) {
 
 void Assembler::adc(Register dst, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(2, Operand(dst), Immediate(imm32));
 }
 
 
 void Assembler::adc(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x13);
   emit_operand(dst, src);
 }
@@ -839,7 +689,6 @@ void Assembler::adc(Register dst, const Operand& src) {
 
 void Assembler::add(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x03);
   emit_operand(dst, src);
 }
@@ -847,24 +696,7 @@ void Assembler::add(Register dst, const Operand& src) {
 
 void Assembler::add(const Operand& dst, const Immediate& x) {
   ASSERT(reloc_info_writer.last_pc() != NULL);
-  if (FLAG_peephole_optimization && (reloc_info_writer.last_pc() <= last_pc_)) {
-    byte instr = last_pc_[0];
-    if ((instr & 0xf8) == 0x50) {
-      // Last instruction was a push. Check whether this is a pop without a
-      // result.
-      if ((dst.is_reg(esp)) &&
-          (x.x_ == kPointerSize) && (x.rmode_ == RelocInfo::NONE)) {
-        pc_ = last_pc_;
-        last_pc_ = NULL;
-        if (FLAG_print_peephole_optimization) {
-          PrintF("%d push/pop(noreg) eliminated\n", pc_offset());
-        }
-        return;
-      }
-    }
-  }
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(0, dst, x);
 }
 
@@ -876,14 +708,12 @@ void Assembler::and_(Register dst, int32_t imm32) {
 
 void Assembler::and_(Register dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(4, Operand(dst), x);
 }
 
 
 void Assembler::and_(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x23);
   emit_operand(dst, src);
 }
@@ -891,14 +721,12 @@ void Assembler::and_(Register dst, const Operand& src) {
 
 void Assembler::and_(const Operand& dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(4, dst, x);
 }
 
 
 void Assembler::and_(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x21);
   emit_operand(src, dst);
 }
@@ -906,7 +734,6 @@ void Assembler::and_(const Operand& dst, Register src) {
 
 void Assembler::cmpb(const Operand& op, int8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x80);
   emit_operand(edi, op);  // edi == 7
   EMIT(imm8);
@@ -916,7 +743,6 @@ void Assembler::cmpb(const Operand& op, int8_t imm8) {
 void Assembler::cmpb(const Operand& dst, Register src) {
   ASSERT(src.is_byte_register());
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x38);
   emit_operand(src, dst);
 }
@@ -925,7 +751,6 @@ void Assembler::cmpb(const Operand& dst, Register src) {
 void Assembler::cmpb(Register dst, const Operand& src) {
   ASSERT(dst.is_byte_register());
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x3A);
   emit_operand(dst, src);
 }
@@ -934,7 +759,6 @@ void Assembler::cmpb(Register dst, const Operand& src) {
 void Assembler::cmpw(const Operand& op, Immediate imm16) {
   ASSERT(imm16.is_int16());
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x81);
   emit_operand(edi, op);
@@ -944,21 +768,18 @@ void Assembler::cmpw(const Operand& op, Immediate imm16) {
 
 void Assembler::cmp(Register reg, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(7, Operand(reg), Immediate(imm32));
 }
 
 
 void Assembler::cmp(Register reg, Handle<Object> handle) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(7, Operand(reg), Immediate(handle));
 }
 
 
 void Assembler::cmp(Register reg, const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x3B);
   emit_operand(reg, op);
 }
@@ -966,21 +787,18 @@ void Assembler::cmp(Register reg, const Operand& op) {
 
 void Assembler::cmp(const Operand& op, const Immediate& imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(7, op, imm);
 }
 
 
 void Assembler::cmp(const Operand& op, Handle<Object> handle) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(7, op, Immediate(handle));
 }
 
 
 void Assembler::cmpb_al(const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x38);  // CMP r/m8, r8
   emit_operand(eax, op);  // eax has same code as register al.
 }
@@ -988,7 +806,6 @@ void Assembler::cmpb_al(const Operand& op) {
 
 void Assembler::cmpw_ax(const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x39);  // CMP r/m16, r16
   emit_operand(eax, op);  // eax has same code as register ax.
@@ -997,7 +814,6 @@ void Assembler::cmpw_ax(const Operand& op) {
 
 void Assembler::dec_b(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFE);
   EMIT(0xC8 | dst.code());
 }
@@ -1005,7 +821,6 @@ void Assembler::dec_b(Register dst) {
 
 void Assembler::dec_b(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFE);
   emit_operand(ecx, dst);
 }
@@ -1013,14 +828,12 @@ void Assembler::dec_b(const Operand& dst) {
 
 void Assembler::dec(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x48 | dst.code());
 }
 
 
 void Assembler::dec(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFF);
   emit_operand(ecx, dst);
 }
@@ -1028,14 +841,12 @@ void Assembler::dec(const Operand& dst) {
 
 void Assembler::cdq() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x99);
 }
 
 
 void Assembler::idiv(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   EMIT(0xF8 | src.code());
 }
@@ -1043,7 +854,6 @@ void Assembler::idiv(Register src) {
 
 void Assembler::imul(Register reg) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   EMIT(0xE8 | reg.code());
 }
@@ -1051,7 +861,6 @@ void Assembler::imul(Register reg) {
 
 void Assembler::imul(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xAF);
   emit_operand(dst, src);
@@ -1060,7 +869,6 @@ void Assembler::imul(Register dst, const Operand& src) {
 
 void Assembler::imul(Register dst, Register src, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (is_int8(imm32)) {
     EMIT(0x6B);
     EMIT(0xC0 | dst.code() << 3 | src.code());
@@ -1075,14 +883,12 @@ void Assembler::imul(Register dst, Register src, int32_t imm32) {
 
 void Assembler::inc(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x40 | dst.code());
 }
 
 
 void Assembler::inc(const Operand& dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFF);
   emit_operand(eax, dst);
 }
@@ -1090,7 +896,6 @@ void Assembler::inc(const Operand& dst) {
 
 void Assembler::lea(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x8D);
   emit_operand(dst, src);
 }
@@ -1098,7 +903,6 @@ void Assembler::lea(Register dst, const Operand& src) {
 
 void Assembler::mul(Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   EMIT(0xE0 | src.code());
 }
@@ -1106,7 +910,6 @@ void Assembler::mul(Register src) {
 
 void Assembler::neg(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   EMIT(0xD8 | dst.code());
 }
@@ -1114,7 +917,6 @@ void Assembler::neg(Register dst) {
 
 void Assembler::not_(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   EMIT(0xD0 | dst.code());
 }
@@ -1122,14 +924,12 @@ void Assembler::not_(Register dst) {
 
 void Assembler::or_(Register dst, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(1, Operand(dst), Immediate(imm32));
 }
 
 
 void Assembler::or_(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0B);
   emit_operand(dst, src);
 }
@@ -1137,14 +937,12 @@ void Assembler::or_(Register dst, const Operand& src) {
 
 void Assembler::or_(const Operand& dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(1, dst, x);
 }
 
 
 void Assembler::or_(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x09);
   emit_operand(src, dst);
 }
@@ -1152,7 +950,6 @@ void Assembler::or_(const Operand& dst, Register src) {
 
 void Assembler::rcl(Register dst, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(imm8));  // illegal shift count
   if (imm8 == 1) {
     EMIT(0xD1);
@@ -1167,7 +964,6 @@ void Assembler::rcl(Register dst, uint8_t imm8) {
 
 void Assembler::rcr(Register dst, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(imm8));  // illegal shift count
   if (imm8 == 1) {
     EMIT(0xD1);
@@ -1182,7 +978,6 @@ void Assembler::rcr(Register dst, uint8_t imm8) {
 
 void Assembler::sar(Register dst, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(imm8));  // illegal shift count
   if (imm8 == 1) {
     EMIT(0xD1);
@@ -1197,7 +992,6 @@ void Assembler::sar(Register dst, uint8_t imm8) {
 
 void Assembler::sar_cl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD3);
   EMIT(0xF8 | dst.code());
 }
@@ -1205,7 +999,6 @@ void Assembler::sar_cl(Register dst) {
 
 void Assembler::sbb(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x1B);
   emit_operand(dst, src);
 }
@@ -1213,7 +1006,6 @@ void Assembler::sbb(Register dst, const Operand& src) {
 
 void Assembler::shld(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xA5);
   emit_operand(dst, src);
@@ -1222,7 +1014,6 @@ void Assembler::shld(Register dst, const Operand& src) {
 
 void Assembler::shl(Register dst, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(imm8));  // illegal shift count
   if (imm8 == 1) {
     EMIT(0xD1);
@@ -1237,7 +1028,6 @@ void Assembler::shl(Register dst, uint8_t imm8) {
 
 void Assembler::shl_cl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD3);
   EMIT(0xE0 | dst.code());
 }
@@ -1245,7 +1035,6 @@ void Assembler::shl_cl(Register dst) {
 
 void Assembler::shrd(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xAD);
   emit_operand(dst, src);
@@ -1254,7 +1043,6 @@ void Assembler::shrd(Register dst, const Operand& src) {
 
 void Assembler::shr(Register dst, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint5(imm8));  // illegal shift count
   if (imm8 == 1) {
     EMIT(0xD1);
@@ -1269,7 +1057,6 @@ void Assembler::shr(Register dst, uint8_t imm8) {
 
 void Assembler::shr_cl(Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD3);
   EMIT(0xE8 | dst.code());
 }
@@ -1277,7 +1064,6 @@ void Assembler::shr_cl(Register dst) {
 
 void Assembler::subb(const Operand& op, int8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (op.is_reg(eax)) {
     EMIT(0x2c);
   } else {
@@ -1290,14 +1076,12 @@ void Assembler::subb(const Operand& op, int8_t imm8) {
 
 void Assembler::sub(const Operand& dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(5, dst, x);
 }
 
 
 void Assembler::sub(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x2B);
   emit_operand(dst, src);
 }
@@ -1306,7 +1090,6 @@ void Assembler::sub(Register dst, const Operand& src) {
 void Assembler::subb(Register dst, const Operand& src) {
   ASSERT(dst.code() < 4);
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x2A);
   emit_operand(dst, src);
 }
@@ -1314,7 +1097,6 @@ void Assembler::subb(Register dst, const Operand& src) {
 
 void Assembler::sub(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x29);
   emit_operand(src, dst);
 }
@@ -1322,7 +1104,6 @@ void Assembler::sub(const Operand& dst, Register src) {
 
 void Assembler::test(Register reg, const Immediate& imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   // Only use test against byte for registers that have a byte
   // variant: eax, ebx, ecx, and edx.
   if (imm.rmode_ == RelocInfo::NONE && is_uint8(imm.x_) && reg.code() < 4) {
@@ -1349,7 +1130,6 @@ void Assembler::test(Register reg, const Immediate& imm) {
 
 void Assembler::test(Register reg, const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x85);
   emit_operand(reg, op);
 }
@@ -1357,7 +1137,6 @@ void Assembler::test(Register reg, const Operand& op) {
 
 void Assembler::test_b(Register reg, const Operand& op) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x84);
   emit_operand(reg, op);
 }
@@ -1365,7 +1144,6 @@ void Assembler::test_b(Register reg, const Operand& op) {
 
 void Assembler::test(const Operand& op, const Immediate& imm) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF7);
   emit_operand(eax, op);
   emit(imm);
@@ -1374,7 +1152,6 @@ void Assembler::test(const Operand& op, const Immediate& imm) {
 
 void Assembler::test_b(const Operand& op, uint8_t imm8) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF6);
   emit_operand(eax, op);
   EMIT(imm8);
@@ -1383,14 +1160,12 @@ void Assembler::test_b(const Operand& op, uint8_t imm8) {
 
 void Assembler::xor_(Register dst, int32_t imm32) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(6, Operand(dst), Immediate(imm32));
 }
 
 
 void Assembler::xor_(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x33);
   emit_operand(dst, src);
 }
@@ -1398,7 +1173,6 @@ void Assembler::xor_(Register dst, const Operand& src) {
 
 void Assembler::xor_(const Operand& src, Register dst) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x31);
   emit_operand(dst, src);
 }
@@ -1406,14 +1180,12 @@ void Assembler::xor_(const Operand& src, Register dst) {
 
 void Assembler::xor_(const Operand& dst, const Immediate& x) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_arith(6, dst, x);
 }
 
 
 void Assembler::bt(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xA3);
   emit_operand(src, dst);
@@ -1422,7 +1194,6 @@ void Assembler::bt(const Operand& dst, Register src) {
 
 void Assembler::bts(const Operand& dst, Register src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0xAB);
   emit_operand(src, dst);
@@ -1431,21 +1202,18 @@ void Assembler::bts(const Operand& dst, Register src) {
 
 void Assembler::hlt() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF4);
 }
 
 
 void Assembler::int3() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xCC);
 }
 
 
 void Assembler::nop() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x90);
 }
 
@@ -1453,7 +1221,6 @@ void Assembler::nop() {
 void Assembler::rdtsc() {
   ASSERT(CpuFeatures::IsEnabled(RDTSC));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0x31);
 }
@@ -1461,7 +1228,6 @@ void Assembler::rdtsc() {
 
 void Assembler::ret(int imm16) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(is_uint16(imm16));
   if (imm16 == 0) {
     EMIT(0xC3);
@@ -1507,7 +1273,6 @@ void Assembler::print(Label* L) {
 
 void Assembler::bind_to(Label* L, int pos) {
   EnsureSpace ensure_space(this);
-  last_pc_ = NULL;
   ASSERT(0 <= pos && pos <= pc_offset());  // must have a valid binding position
   while (L->is_linked()) {
     Displacement disp = disp_at(L);
@@ -1546,7 +1311,6 @@ void Assembler::bind_to(Label* L, int pos) {
 
 void Assembler::bind(Label* L) {
   EnsureSpace ensure_space(this);
-  last_pc_ = NULL;
   ASSERT(!L->is_bound());  // label can only be bound once
   bind_to(L, pc_offset());
 }
@@ -1555,7 +1319,6 @@ void Assembler::bind(Label* L) {
 void Assembler::call(Label* L) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (L->is_bound()) {
     const int long_size = 5;
     int offs = L->pos() - pc_offset();
@@ -1574,7 +1337,6 @@ void Assembler::call(Label* L) {
 void Assembler::call(byte* entry, RelocInfo::Mode rmode) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(!RelocInfo::IsCodeTarget(rmode));
   EMIT(0xE8);
   emit(entry - (pc_ + sizeof(int32_t)), rmode);
@@ -1590,10 +1352,8 @@ int Assembler::CallSize(const Operand& adr) {
 void Assembler::call(const Operand& adr) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFF);
   emit_operand(edx, adr);
-  ASSERT(pc_ - last_pc_ == CallSize(adr));
 }
 
 
@@ -1607,7 +1367,6 @@ void Assembler::call(Handle<Code> code,
                      unsigned ast_id) {
   positions_recorder()->WriteRecordedPositions();
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(RelocInfo::IsCodeTarget(rmode));
   EMIT(0xE8);
   emit(reinterpret_cast<intptr_t>(code.location()), rmode, ast_id);
@@ -1616,7 +1375,6 @@ void Assembler::call(Handle<Code> code,
 
 void Assembler::jmp(Label* L, Label::Distance distance) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (L->is_bound()) {
     const int short_size = 2;
     const int long_size  = 5;
@@ -1644,7 +1402,6 @@ void Assembler::jmp(Label* L, Label::Distance distance) {
 
 void Assembler::jmp(byte* entry, RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(!RelocInfo::IsCodeTarget(rmode));
   EMIT(0xE9);
   emit(entry - (pc_ + sizeof(int32_t)), rmode);
@@ -1653,7 +1410,6 @@ void Assembler::jmp(byte* entry, RelocInfo::Mode rmode) {
 
 void Assembler::jmp(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xFF);
   emit_operand(esp, adr);
 }
@@ -1661,7 +1417,6 @@ void Assembler::jmp(const Operand& adr) {
 
 void Assembler::jmp(Handle<Code> code, RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   ASSERT(RelocInfo::IsCodeTarget(rmode));
   EMIT(0xE9);
   emit(reinterpret_cast<intptr_t>(code.location()), rmode);
@@ -1670,7 +1425,6 @@ void Assembler::jmp(Handle<Code> code, RelocInfo::Mode rmode) {
 
 void Assembler::j(Condition cc, Label* L, Hint hint, Label::Distance distance) {
   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()) {
@@ -1704,7 +1458,6 @@ void Assembler::j(Condition cc, Label* L, Hint hint, Label::Distance distance) {
 
 void Assembler::j(Condition cc, byte* entry, RelocInfo::Mode rmode, Hint hint) {
   EnsureSpace ensure_space(this);
-  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.
@@ -1716,7 +1469,6 @@ void Assembler::j(Condition cc, byte* entry, RelocInfo::Mode rmode, Hint hint) {
 
 void Assembler::j(Condition cc, Handle<Code> code, Hint hint) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   if (FLAG_emit_branch_hints && hint != no_hint) EMIT(hint);
   // 0000 1111 1000 tttn #32-bit disp
   EMIT(0x0F);
@@ -1729,21 +1481,18 @@ void Assembler::j(Condition cc, Handle<Code> code, Hint hint) {
 
 void Assembler::fld(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xD9, 0xC0, i);
 }
 
 
 void Assembler::fstp(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   emit_farith(0xDD, 0xD8, i);
 }
 
 
 void Assembler::fld1() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xE8);
 }
@@ -1751,7 +1500,6 @@ void Assembler::fld1() {
 
 void Assembler::fldpi() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xEB);
 }
@@ -1759,7 +1507,6 @@ void Assembler::fldpi() {
 
 void Assembler::fldz() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xEE);
 }
@@ -1767,7 +1514,6 @@ void Assembler::fldz() {
 
 void Assembler::fldln2() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xED);
 }
@@ -1775,7 +1521,6 @@ void Assembler::fldln2() {
 
 void Assembler::fld_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   emit_operand(eax, adr);
 }
@@ -1783,7 +1528,6 @@ void Assembler::fld_s(const Operand& adr) {
 
 void Assembler::fld_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDD);
   emit_operand(eax, adr);
 }
@@ -1791,7 +1535,6 @@ void Assembler::fld_d(const Operand& adr) {
 
 void Assembler::fstp_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   emit_operand(ebx, adr);
 }
@@ -1799,7 +1542,6 @@ void Assembler::fstp_s(const Operand& adr) {
 
 void Assembler::fstp_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDD);
   emit_operand(ebx, adr);
 }
@@ -1807,7 +1549,6 @@ void Assembler::fstp_d(const Operand& adr) {
 
 void Assembler::fst_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDD);
   emit_operand(edx, adr);
 }
@@ -1815,7 +1556,6 @@ void Assembler::fst_d(const Operand& adr) {
 
 void Assembler::fild_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   emit_operand(eax, adr);
 }
@@ -1823,7 +1563,6 @@ void Assembler::fild_s(const Operand& adr) {
 
 void Assembler::fild_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDF);
   emit_operand(ebp, adr);
 }
@@ -1831,7 +1570,6 @@ void Assembler::fild_d(const Operand& adr) {
 
 void Assembler::fistp_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   emit_operand(ebx, adr);
 }
@@ -1840,7 +1578,6 @@ void Assembler::fistp_s(const Operand& adr) {
 void Assembler::fisttp_s(const Operand& adr) {
   ASSERT(CpuFeatures::IsEnabled(SSE3));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   emit_operand(ecx, adr);
 }
@@ -1849,7 +1586,6 @@ void Assembler::fisttp_s(const Operand& adr) {
 void Assembler::fisttp_d(const Operand& adr) {
   ASSERT(CpuFeatures::IsEnabled(SSE3));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDD);
   emit_operand(ecx, adr);
 }
@@ -1857,7 +1593,6 @@ void Assembler::fisttp_d(const Operand& adr) {
 
 void Assembler::fist_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   emit_operand(edx, adr);
 }
@@ -1865,7 +1600,6 @@ void Assembler::fist_s(const Operand& adr) {
 
 void Assembler::fistp_d(const Operand& adr) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDF);
   emit_operand(edi, adr);
 }
@@ -1873,7 +1607,6 @@ void Assembler::fistp_d(const Operand& adr) {
 
 void Assembler::fabs() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xE1);
 }
@@ -1881,7 +1614,6 @@ void Assembler::fabs() {
 
 void Assembler::fchs() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xE0);
 }
@@ -1889,7 +1621,6 @@ void Assembler::fchs() {
 
 void Assembler::fcos() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xFF);
 }
@@ -1897,7 +1628,6 @@ void Assembler::fcos() {
 
 void Assembler::fsin() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xFE);
 }
@@ -1905,7 +1635,6 @@ void Assembler::fsin() {
 
 void Assembler::fyl2x() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xF1);
 }
@@ -1913,21 +1642,18 @@ void Assembler::fyl2x() {
 
 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(0xDA);
   emit_operand(esp, adr);
 }
@@ -1935,56 +1661,48 @@ void Assembler::fisub_s(const Operand& 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);
 }
@@ -1992,7 +1710,6 @@ void Assembler::fprem() {
 
 void Assembler::fprem1() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xD9);
   EMIT(0xF5);
 }
@@ -2000,14 +1717,12 @@ void Assembler::fprem1() {
 
 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);
 }
@@ -2015,14 +1730,12 @@ void Assembler::fincstp() {
 
 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);
 }
@@ -2030,14 +1743,12 @@ void Assembler::ftst() {
 
 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);
 }
@@ -2045,7 +1756,6 @@ void Assembler::fucompp() {
 
 void Assembler::fucomi(int i) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   EMIT(0xE8 + i);
 }
@@ -2053,7 +1763,6 @@ void Assembler::fucomi(int i) {
 
 void Assembler::fucomip() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDF);
   EMIT(0xE9);
 }
@@ -2061,7 +1770,6 @@ void Assembler::fucomip() {
 
 void Assembler::fcompp() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDE);
   EMIT(0xD9);
 }
@@ -2069,7 +1777,6 @@ void Assembler::fcompp() {
 
 void Assembler::fnstsw_ax() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDF);
   EMIT(0xE0);
 }
@@ -2077,14 +1784,12 @@ void Assembler::fnstsw_ax() {
 
 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);
 }
@@ -2092,7 +1797,6 @@ void Assembler::frndint() {
 
 void Assembler::fnclex() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xDB);
   EMIT(0xE2);
 }
@@ -2100,7 +1804,6 @@ void Assembler::fnclex() {
 
 void Assembler::sahf() {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x9E);
 }
 
@@ -2108,7 +1811,6 @@ void Assembler::sahf() {
 void Assembler::setcc(Condition cc, Register reg) {
   ASSERT(reg.is_byte_register());
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0x90 | cc);
   EMIT(0xC0 | reg.code());
@@ -2118,7 +1820,6 @@ void Assembler::setcc(Condition cc, Register reg) {
 void Assembler::cvttss2si(Register dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0x0F);
   EMIT(0x2C);
@@ -2129,7 +1830,6 @@ void Assembler::cvttss2si(Register dst, const Operand& src) {
 void Assembler::cvttsd2si(Register dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x2C);
@@ -2140,7 +1840,6 @@ void Assembler::cvttsd2si(Register dst, const Operand& src) {
 void Assembler::cvtsi2sd(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x2A);
@@ -2151,7 +1850,6 @@ void Assembler::cvtsi2sd(XMMRegister dst, const Operand& src) {
 void Assembler::cvtss2sd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0x0F);
   EMIT(0x5A);
@@ -2162,7 +1860,6 @@ void Assembler::cvtss2sd(XMMRegister dst, XMMRegister src) {
 void Assembler::cvtsd2ss(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x5A);
@@ -2173,7 +1870,6 @@ void Assembler::cvtsd2ss(XMMRegister dst, XMMRegister src) {
 void Assembler::addsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x58);
@@ -2184,7 +1880,6 @@ void Assembler::addsd(XMMRegister dst, XMMRegister src) {
 void Assembler::mulsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x59);
@@ -2195,7 +1890,6 @@ void Assembler::mulsd(XMMRegister dst, XMMRegister src) {
 void Assembler::subsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x5C);
@@ -2206,7 +1900,6 @@ void Assembler::subsd(XMMRegister dst, XMMRegister src) {
 void Assembler::divsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x5E);
@@ -2217,7 +1910,6 @@ void Assembler::divsd(XMMRegister dst, XMMRegister src) {
 void Assembler::xorpd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x57);
@@ -2227,7 +1919,6 @@ void Assembler::xorpd(XMMRegister dst, XMMRegister src) {
 
 void Assembler::xorps(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0x57);
   emit_sse_operand(dst, src);
@@ -2236,7 +1927,6 @@ void Assembler::xorps(XMMRegister dst, XMMRegister src) {
 
 void Assembler::sqrtsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x51);
@@ -2246,7 +1936,6 @@ void Assembler::sqrtsd(XMMRegister dst, XMMRegister src) {
 
 void Assembler::andpd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x54);
@@ -2257,7 +1946,6 @@ void Assembler::andpd(XMMRegister dst, XMMRegister src) {
 void Assembler::ucomisd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x2E);
@@ -2268,7 +1956,6 @@ void Assembler::ucomisd(XMMRegister dst, XMMRegister src) {
 void Assembler::movmskpd(Register dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x50);
@@ -2279,7 +1966,6 @@ void Assembler::movmskpd(Register dst, XMMRegister src) {
 void Assembler::cmpltsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0xC2);
@@ -2291,7 +1977,6 @@ void Assembler::cmpltsd(XMMRegister dst, XMMRegister src) {
 void Assembler::movaps(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0x28);
   emit_sse_operand(dst, src);
@@ -2301,7 +1986,6 @@ void Assembler::movaps(XMMRegister dst, XMMRegister src) {
 void Assembler::movdqa(const Operand& dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x7F);
@@ -2312,7 +1996,6 @@ void Assembler::movdqa(const Operand& dst, XMMRegister src) {
 void Assembler::movdqa(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x6F);
@@ -2323,7 +2006,6 @@ void Assembler::movdqa(XMMRegister dst, const Operand& src) {
 void Assembler::movdqu(const Operand& dst, XMMRegister src ) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0x0F);
   EMIT(0x7F);
@@ -2334,7 +2016,6 @@ void Assembler::movdqu(const Operand& dst, XMMRegister src ) {
 void Assembler::movdqu(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0x0F);
   EMIT(0x6F);
@@ -2345,7 +2026,6 @@ void Assembler::movdqu(XMMRegister dst, const Operand& src) {
 void Assembler::movntdqa(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE4_1));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x38);
@@ -2357,7 +2037,6 @@ void Assembler::movntdqa(XMMRegister dst, const Operand& src) {
 void Assembler::movntdq(const Operand& dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xE7);
@@ -2368,7 +2047,6 @@ void Assembler::movntdq(const Operand& dst, XMMRegister src) {
 void Assembler::prefetch(const Operand& src, int level) {
   ASSERT(is_uint2(level));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x0F);
   EMIT(0x18);
   XMMRegister code = { level };  // Emit hint number in Reg position of RegR/M.
@@ -2378,14 +2056,12 @@ void Assembler::prefetch(const Operand& src, int level) {
 
 void Assembler::movdbl(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   movsd(dst, src);
 }
 
 
 void Assembler::movdbl(const Operand& dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   movsd(dst, src);
 }
 
@@ -2393,7 +2069,6 @@ void Assembler::movdbl(const Operand& dst, XMMRegister src) {
 void Assembler::movsd(const Operand& dst, XMMRegister src ) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);  // double
   EMIT(0x0F);
   EMIT(0x11);  // store
@@ -2404,7 +2079,6 @@ void Assembler::movsd(const Operand& dst, XMMRegister src ) {
 void Assembler::movsd(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);  // double
   EMIT(0x0F);
   EMIT(0x10);  // load
@@ -2415,7 +2089,6 @@ void Assembler::movsd(XMMRegister dst, const Operand& src) {
 void Assembler::movsd(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF2);
   EMIT(0x0F);
   EMIT(0x10);
@@ -2426,7 +2099,6 @@ void Assembler::movsd(XMMRegister dst, XMMRegister src) {
 void Assembler::movss(const Operand& dst, XMMRegister src ) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);  // float
   EMIT(0x0F);
   EMIT(0x11);  // store
@@ -2437,7 +2109,6 @@ void Assembler::movss(const Operand& dst, XMMRegister src ) {
 void Assembler::movss(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);  // float
   EMIT(0x0F);
   EMIT(0x10);  // load
@@ -2448,7 +2119,6 @@ void Assembler::movss(XMMRegister dst, const Operand& src) {
 void Assembler::movss(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0xF3);
   EMIT(0x0F);
   EMIT(0x10);
@@ -2459,7 +2129,6 @@ void Assembler::movss(XMMRegister dst, XMMRegister src) {
 void Assembler::movd(XMMRegister dst, const Operand& src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x6E);
@@ -2470,7 +2139,6 @@ void Assembler::movd(XMMRegister dst, const Operand& src) {
 void Assembler::movd(const Operand& dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x7E);
@@ -2481,7 +2149,6 @@ void Assembler::movd(const Operand& dst, XMMRegister src) {
 void Assembler::pand(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xDB);
@@ -2492,7 +2159,6 @@ void Assembler::pand(XMMRegister dst, XMMRegister src) {
 void Assembler::pxor(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xEF);
@@ -2503,7 +2169,6 @@ void Assembler::pxor(XMMRegister dst, XMMRegister src) {
 void Assembler::por(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xEB);
@@ -2514,7 +2179,6 @@ void Assembler::por(XMMRegister dst, XMMRegister src) {
 void Assembler::ptest(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE4_1));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x38);
@@ -2526,7 +2190,6 @@ void Assembler::ptest(XMMRegister dst, XMMRegister src) {
 void Assembler::psllq(XMMRegister reg, int8_t shift) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x73);
@@ -2538,7 +2201,6 @@ void Assembler::psllq(XMMRegister reg, int8_t shift) {
 void Assembler::psllq(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xF3);
@@ -2549,7 +2211,6 @@ void Assembler::psllq(XMMRegister dst, XMMRegister src) {
 void Assembler::psrlq(XMMRegister reg, int8_t shift) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x73);
@@ -2561,7 +2222,6 @@ void Assembler::psrlq(XMMRegister reg, int8_t shift) {
 void Assembler::psrlq(XMMRegister dst, XMMRegister src) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0xD3);
@@ -2572,7 +2232,6 @@ void Assembler::psrlq(XMMRegister dst, XMMRegister src) {
 void Assembler::pshufd(XMMRegister dst, XMMRegister src, int8_t shuffle) {
   ASSERT(CpuFeatures::IsEnabled(SSE2));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x70);
@@ -2584,7 +2243,6 @@ void Assembler::pshufd(XMMRegister dst, XMMRegister src, int8_t shuffle) {
 void Assembler::pextrd(const Operand& dst, XMMRegister src, int8_t offset) {
   ASSERT(CpuFeatures::IsEnabled(SSE4_1));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x3A);
@@ -2597,7 +2255,6 @@ void Assembler::pextrd(const Operand& dst, XMMRegister src, int8_t offset) {
 void Assembler::pinsrd(XMMRegister dst, const Operand& src, int8_t offset) {
   ASSERT(CpuFeatures::IsEnabled(SSE4_1));
   EnsureSpace ensure_space(this);
-  last_pc_ = pc_;
   EMIT(0x66);
   EMIT(0x0F);
   EMIT(0x3A);
@@ -2696,9 +2353,6 @@ void Assembler::GrowBuffer() {
   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);
 

diff --git a/src/ia32/assembler-ia32.h b/src/ia32/assembler-ia32.h
index d47c8d9..cd55da7 100644 (file)
--- a/src/ia32/assembler-ia32.h
+++ b/src/ia32/assembler-ia32.h
@@ -1124,9 +1124,6 @@ class Assembler : public AssemblerBase {
   byte* pc_;  // the program counter; moves forward
   RelocInfoWriter reloc_info_writer;
 
-  // push-pop elimination
-  byte* last_pc_;
-
   PositionsRecorder positions_recorder_;
 
   bool emit_debug_code_;