[turbofan] Avoid unnecessary write barriers and improve code generation.

src/compiler/ia32/code-generator-ia32.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/osr.h"
@@ skipping 199 matching lines @@
     __ movsd(MemOperand(esp, 0), input_);
     __ SlowTruncateToI(result_, esp, 0);
     __ add(esp, Immediate(kDoubleSize));
   }
 
  private:
   Register const result_;
   XMMRegister const input_;
 };
 
+
+class OutOfLineRecordWrite final : public OutOfLineCode {
+ public:
+  OutOfLineRecordWrite(CodeGenerator* gen, Register object, Operand operand,
+                       Register value, Register scratch0, Register scratch1,
+                       RecordWriteMode mode)
+      : OutOfLineCode(gen),
+        object_(object),
+        operand_(operand),
+        value_(value),
+        scratch0_(scratch0),
+        scratch1_(scratch1),
+        mode_(mode) {}
+
+  void Generate() final {
+    if (mode_ > RecordWriteMode::kValueIsPointer) {
+      __ JumpIfSmi(value_, exit());
+    }
+    if (mode_ > RecordWriteMode::kValueIsMap) {
+      __ CheckPageFlag(value_, scratch0_,
+                       MemoryChunk::kPointersToHereAreInterestingMask, zero,
+                       exit());
+    }
+    SaveFPRegsMode const save_fp_mode =
+        frame()->DidAllocateDoubleRegisters() ? kSaveFPRegs : kDontSaveFPRegs;
+    RecordWriteStub stub(isolate(), object_, scratch0_, scratch1_,
+                         EMIT_REMEMBERED_SET, save_fp_mode);
+    __ lea(scratch1_, operand_);
+    __ CallStub(&stub);
+  }
+
+ private:
+  Register const object_;
+  Operand const operand_;
+  Register const value_;
+  Register const scratch0_;
+  Register const scratch1_;
+  RecordWriteMode const mode_;
+};
+
 }  // namespace
 
 
 #define ASSEMBLE_CHECKED_LOAD_FLOAT(asm_instr)                          \
   do {                                                                  \
     auto result = i.OutputDoubleRegister();                             \
     auto offset = i.InputRegister(0);                                   \
     if (instr->InputAt(1)->IsRegister()) {                              \
       __ cmp(offset, i.InputRegister(1));                               \
     } else {                                                            \
@@ skipping 170 matching lines @@
     case kArchTruncateDoubleToI: {
       auto result = i.OutputRegister();
       auto input = i.InputDoubleRegister(0);
       auto ool = new (zone()) OutOfLineTruncateDoubleToI(this, result, input);
       __ cvttsd2si(result, Operand(input));
       __ cmp(result, 1);
       __ j(overflow, ool->entry());
       __ bind(ool->exit());
       break;
     }
+    case kArchStoreWithWriteBarrier: {
+      RecordWriteMode mode =
+          static_cast<RecordWriteMode>(MiscField::decode(instr->opcode()));
+      Register object = i.InputRegister(0);
+      size_t index = 0;
+      Operand operand = i.MemoryOperand(&index);
+      Register value = i.InputRegister(index);
+      Register scratch0 = i.TempRegister(0);
+      Register scratch1 = i.TempRegister(1);
+      auto ool = new (zone()) OutOfLineRecordWrite(this, object, operand, value,
+                                                   scratch0, scratch1, mode);
+      __ mov(operand, value);
+      __ CheckPageFlag(object, scratch0,
+                       MemoryChunk::kPointersFromHereAreInterestingMask,
+                       not_zero, ool->entry());
+      __ bind(ool->exit());
+      break;
+    }
     case kIA32Add:
       if (HasImmediateInput(instr, 1)) {
         __ add(i.InputOperand(0), i.InputImmediate(1));
       } else {
         __ add(i.InputRegister(0), i.InputOperand(1));
       }
       break;
     case kIA32And:
       if (HasImmediateInput(instr, 1)) {
         __ and_(i.InputOperand(0), i.InputImmediate(1));
@@ skipping 493 matching lines @@
       break;
     case kIA32Poke: {
       int const slot = MiscField::decode(instr->opcode());
       if (HasImmediateInput(instr, 0)) {
         __ mov(Operand(esp, slot * kPointerSize), i.InputImmediate(0));
       } else {
         __ mov(Operand(esp, slot * kPointerSize), i.InputRegister(0));
       }
       break;
     }
-    case kIA32StoreWriteBarrier: {
-      Register object = i.InputRegister(0);
-      Register value = i.InputRegister(2);
-      SaveFPRegsMode mode =
-          frame()->DidAllocateDoubleRegisters() ? kSaveFPRegs : kDontSaveFPRegs;
-      if (HasImmediateInput(instr, 1)) {
-        int index = i.InputInt32(1);
-        Register scratch = i.TempRegister(1);
-        __ mov(Operand(object, index), value);
-        __ RecordWriteContextSlot(object, index, value, scratch, mode);
-      } else {
-        Register index = i.InputRegister(1);
-        __ mov(Operand(object, index, times_1, 0), value);
-        __ lea(index, Operand(object, index, times_1, 0));
-        __ RecordWrite(object, index, value, mode);
-      }
-      break;
-    }
     case kCheckedLoadInt8:
       ASSEMBLE_CHECKED_LOAD_INTEGER(movsx_b);
       break;
     case kCheckedLoadUint8:
       ASSEMBLE_CHECKED_LOAD_INTEGER(movzx_b);
       break;
     case kCheckedLoadInt16:
       ASSEMBLE_CHECKED_LOAD_INTEGER(movsx_w);
       break;
     case kCheckedLoadUint16:
@@ skipping 615 matching lines @@
     int padding_size = last_lazy_deopt_pc_ + space_needed - current_pc;
     __ Nop(padding_size);
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8