[turbofan] Desugar JSUnaryNot(x) to Select(x, false, true).

src/compiler/ast-graph-builder.cc

 // Copyright 2014 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/ast-graph-builder.h"
 
 #include "src/ast/scopes.h"
 #include "src/compiler.h"
 #include "src/compiler/ast-loop-assignment-analyzer.h"
 #include "src/compiler/control-builders.h"
@@ skipping 2993 matching lines @@
     operand = environment()->Pop();
   }
   Node* value = NewNode(javascript()->TypeOf(), operand);
   ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitNot(UnaryOperation* expr) {
   VisitForValue(expr->expression());
   Node* operand = environment()->Pop();
-  // TODO(mstarzinger): Possible optimization when we are in effect context.
-  Node* value = NewNode(javascript()->UnaryNot(), operand);
+  Node* input = BuildToBoolean(operand);
+  Node* value = NewNode(common()->Select(kMachAnyTagged), input,
+                        jsgraph()->FalseConstant(), jsgraph()->TrueConstant());
   ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitComma(BinaryOperation* expr) {
   VisitForEffect(expr->left());
   Visit(expr->right());
   ast_context()->ReplaceValue();
 }
 
@@ skipping 927 matching lines @@
       return jsgraph_->BooleanConstant(object->BooleanValue());
     }
     case IrOpcode::kJSEqual:
     case IrOpcode::kJSNotEqual:
     case IrOpcode::kJSStrictEqual:
     case IrOpcode::kJSStrictNotEqual:
     case IrOpcode::kJSLessThan:
     case IrOpcode::kJSLessThanOrEqual:
     case IrOpcode::kJSGreaterThan:
     case IrOpcode::kJSGreaterThanOrEqual:
-    case IrOpcode::kJSUnaryNot:
     case IrOpcode::kJSToBoolean:
     case IrOpcode::kJSDeleteProperty:
     case IrOpcode::kJSHasProperty:
     case IrOpcode::kJSInstanceOf:
       return input;
     default:
       break;
   }
   return nullptr;
 }
@@ skipping 343 matching lines @@
     // Phi does not exist yet, introduce one.
     value = NewPhi(inputs, value, control);
     value->ReplaceInput(inputs - 1, other);
   }
   return value;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8