[stubs] Improve code generation for ToBoolean.

src/interpreter/interpreter.cc

 // Copyright 2015 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/interpreter/interpreter.h"
 
 #include <fstream>
 
 #include "src/ast/prettyprinter.h"
 #include "src/code-factory.h"
@@ skipping 1034 matching lines @@
   DoUnaryOp<IncStub>(assembler);
 }
 
 // Dec
 //
 // Decrements value in the accumulator by one.
 void Interpreter::DoDec(InterpreterAssembler* assembler) {
   DoUnaryOp<DecStub>(assembler);
 }
 
-Node* Interpreter::BuildToBoolean(Node* value,
-                                  InterpreterAssembler* assembler) {
-  Node* context = __ GetContext();
-  return ToBooleanStub::Generate(assembler, value, context);
-}
-
-Node* Interpreter::BuildLogicalNot(Node* value,
-                                   InterpreterAssembler* assembler) {
+// LogicalNot
+//
+// Perform logical-not on the accumulator, first casting the
+// accumulator to a boolean value if required.
+// ToBooleanLogicalNot
+void Interpreter::DoToBooleanLogicalNot(InterpreterAssembler* assembler) {
+  Node* value = __ GetAccumulator();
   Variable result(assembler, MachineRepresentation::kTagged);
   Label if_true(assembler), if_false(assembler), end(assembler);
   Node* true_value = __ BooleanConstant(true);
   Node* false_value = __ BooleanConstant(false);
-  __ BranchIfWordEqual(value, true_value, &if_true, &if_false);
+  __ BranchIfToBooleanIsTrue(value, &if_true, &if_false);
   __ Bind(&if_true);
   {
     result.Bind(false_value);
     __ Goto(&end);
   }
   __ Bind(&if_false);
   {
-    if (FLAG_debug_code) {
-      __ AbortIfWordNotEqual(value, false_value,
-                             BailoutReason::kExpectedBooleanValue);
-    }
     result.Bind(true_value);
     __ Goto(&end);
   }
   __ Bind(&end);
-  return result.value();
-}
-
-// LogicalNot
-//
-// Perform logical-not on the accumulator, first casting the
-// accumulator to a boolean value if required.
-// ToBooleanLogicalNot
-void Interpreter::DoToBooleanLogicalNot(InterpreterAssembler* assembler) {
-  Node* value = __ GetAccumulator();
-  Node* to_boolean_value = BuildToBoolean(value, assembler);
-  Node* result = BuildLogicalNot(to_boolean_value, assembler);
-  __ SetAccumulator(result);
+  __ SetAccumulator(result.value());
   __ Dispatch();
 }
 
 // LogicalNot
 //
 // Perform logical-not on the accumulator, which must already be a boolean
 // value.
 void Interpreter::DoLogicalNot(InterpreterAssembler* assembler) {
   Node* value = __ GetAccumulator();
-  Node* result = BuildLogicalNot(value, assembler);
-  __ SetAccumulator(result);
+  Variable result(assembler, MachineRepresentation::kTagged);
+  Label if_true(assembler), if_false(assembler), end(assembler);
+  Node* true_value = __ BooleanConstant(true);
+  Node* false_value = __ BooleanConstant(false);
+  __ BranchIfWordEqual(value, true_value, &if_true, &if_false);
+  __ Bind(&if_true);
+  {
+    result.Bind(false_value);
+    __ Goto(&end);
+  }
+  __ Bind(&if_false);
+  {
+    if (FLAG_debug_code) {
+      __ AbortIfWordNotEqual(value, false_value,
+                             BailoutReason::kExpectedBooleanValue);
+    }
+    result.Bind(true_value);
+    __ Goto(&end);
+  }
+  __ Bind(&end);
+  __ SetAccumulator(result.value());
   __ Dispatch();
 }
 
 // TypeOf
 //
 // Load the accumulator with the string representating type of the
 // object in the accumulator.
 void Interpreter::DoTypeOf(InterpreterAssembler* assembler) {
   DoUnaryOp(CodeFactory::Typeof(isolate_), assembler);
 }
@@ skipping 314 matching lines @@
   Node* relative_jump = __ SmiUntag(constant);
   Node* false_value = __ BooleanConstant(false);
   __ JumpIfWordEqual(accumulator, false_value, relative_jump);
 }
 
 // JumpIfToBooleanTrue <imm>
 //
 // Jump by number of bytes represented by an immediate operand if the object
 // referenced by the accumulator is true when the object is cast to boolean.
 void Interpreter::DoJumpIfToBooleanTrue(InterpreterAssembler* assembler) {
-  Node* accumulator = __ GetAccumulator();
-  Node* to_boolean_value = BuildToBoolean(accumulator, assembler);
+  Node* value = __ GetAccumulator();
   Node* relative_jump = __ BytecodeOperandImm(0);
-  Node* true_value = __ BooleanConstant(true);
-  __ JumpIfWordEqual(to_boolean_value, true_value, relative_jump);
+  Label if_true(assembler), if_false(assembler);
+  __ BranchIfToBooleanIsTrue(value, &if_true, &if_false);
+  __ Bind(&if_true);
+  __ Jump(relative_jump);
+  __ Bind(&if_false);
+  __ Dispatch();
 }
 
 // JumpIfToBooleanTrueConstant <idx>
 //
 // Jump by number of bytes in the Smi in the |idx| entry in the constant pool
 // if the object referenced by the accumulator is true when the object is cast
 // to boolean.
 void Interpreter::DoJumpIfToBooleanTrueConstant(
     InterpreterAssembler* assembler) {
-  Node* accumulator = __ GetAccumulator();
-  Node* to_boolean_value = BuildToBoolean(accumulator, assembler);
+  Node* value = __ GetAccumulator();
   Node* index = __ BytecodeOperandIdx(0);
   Node* constant = __ LoadConstantPoolEntry(index);
   Node* relative_jump = __ SmiUntag(constant);
-  Node* true_value = __ BooleanConstant(true);
-  __ JumpIfWordEqual(to_boolean_value, true_value, relative_jump);
+  Label if_true(assembler), if_false(assembler);
+  __ BranchIfToBooleanIsTrue(value, &if_true, &if_false);
+  __ Bind(&if_true);
+  __ Jump(relative_jump);
+  __ Bind(&if_false);
+  __ Dispatch();
 }
 
 // JumpIfToBooleanFalse <imm>
 //
 // Jump by number of bytes represented by an immediate operand if the object
 // referenced by the accumulator is false when the object is cast to boolean.
 void Interpreter::DoJumpIfToBooleanFalse(InterpreterAssembler* assembler) {
-  Node* accumulator = __ GetAccumulator();
-  Node* to_boolean_value = BuildToBoolean(accumulator, assembler);
+  Node* value = __ GetAccumulator();
   Node* relative_jump = __ BytecodeOperandImm(0);
-  Node* false_value = __ BooleanConstant(false);
-  __ JumpIfWordEqual(to_boolean_value, false_value, relative_jump);
+  Label if_true(assembler), if_false(assembler);
+  __ BranchIfToBooleanIsTrue(value, &if_true, &if_false);
+  __ Bind(&if_true);
+  __ Dispatch();
+  __ Bind(&if_false);
+  __ Jump(relative_jump);
 }
 
 // JumpIfToBooleanFalseConstant <idx>
 //
 // Jump by number of bytes in the Smi in the |idx| entry in the constant pool
 // if the object referenced by the accumulator is false when the object is cast
 // to boolean.
 void Interpreter::DoJumpIfToBooleanFalseConstant(
     InterpreterAssembler* assembler) {
-  Node* accumulator = __ GetAccumulator();
-  Node* to_boolean_value = BuildToBoolean(accumulator, assembler);
+  Node* value = __ GetAccumulator();
   Node* index = __ BytecodeOperandIdx(0);
   Node* constant = __ LoadConstantPoolEntry(index);
   Node* relative_jump = __ SmiUntag(constant);
-  Node* false_value = __ BooleanConstant(false);
-  __ JumpIfWordEqual(to_boolean_value, false_value, relative_jump);
+  Label if_true(assembler), if_false(assembler);
+  __ BranchIfToBooleanIsTrue(value, &if_true, &if_false);
+  __ Bind(&if_true);
+  __ Dispatch();
+  __ Bind(&if_false);
+  __ Jump(relative_jump);
 }
 
 // JumpIfNull <imm>
 //
 // Jump by number of bytes represented by an immediate operand if the object
 // referenced by the accumulator is the null constant.
 void Interpreter::DoJumpIfNull(InterpreterAssembler* assembler) {
   Node* accumulator = __ GetAccumulator();
   Node* null_value = __ HeapConstant(isolate_->factory()->null_value());
   Node* relative_jump = __ BytecodeOperandImm(0);
@@ skipping 521 matching lines @@
   __ StoreObjectField(generator, JSGeneratorObject::kContinuationOffset,
       __ SmiTag(new_state));
   __ SetAccumulator(old_state);
 
   __ Dispatch();
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8