[builtins] Make Math.ceil, Math.trunc and Math.round optimizable.

src/builtins.cc

 // Copyright 2012 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/builtins.h"
 
 #include "src/api.h"
 #include "src/api-arguments.h"
 #include "src/api-natives.h"
 #include "src/base/once.h"
@@ skipping 1989 matching lines @@
 
 // ES6 section 20.2.2.6 Math.atan ( x )
 BUILTIN(MathAtan) {
   HandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
   Handle<Object> x = args.at<Object>(1);
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, x, Object::ToNumber(x));
   return *isolate->factory()->NewHeapNumber(std::atan(x->Number()));
 }
 
-// ES6 section 20.2.2.16 Math.floor ( x )
-void Builtins::Generate_MathFloor(compiler::CodeStubAssembler* assembler) {
+namespace {
+
+void Generate_MathRoundingOperation(
+    compiler::CodeStubAssembler* assembler,
+    compiler::Node* (compiler::CodeStubAssembler::*float64op)(
+        compiler::Node*)) {
   typedef compiler::CodeStubAssembler::Label Label;
   typedef compiler::Node Node;
   typedef compiler::CodeStubAssembler::Variable Variable;
 
   Node* context = assembler->Parameter(4);
 
   // We might need to loop once for ToNumber conversion.
   Variable var_x(assembler, MachineRepresentation::kTagged);
   Label loop(assembler, &var_x);
   var_x.Bind(assembler->Parameter(1));
@@ skipping 19 matching lines @@
       Label if_xisheapnumber(assembler),
           if_xisnotheapnumber(assembler, Label::kDeferred);
       assembler->Branch(
           assembler->WordEqual(assembler->LoadMap(x),
                                assembler->HeapNumberMapConstant()),
           &if_xisheapnumber, &if_xisnotheapnumber);
 
       assembler->Bind(&if_xisheapnumber);
       {
         Node* x_value = assembler->LoadHeapNumberValue(x);
-        Node* value = assembler->Float64Floor(x_value);
+        Node* value = (assembler->*float64op)(x_value);
         Node* result = assembler->ChangeFloat64ToTagged(value);
         assembler->Return(result);
       }
 
       assembler->Bind(&if_xisnotheapnumber);
       {
         // Need to convert {x} to a Number first.
         Callable callable =
             CodeFactory::NonNumberToNumber(assembler->isolate());
         var_x.Bind(assembler->CallStub(callable, context, x));
         assembler->Goto(&loop);
       }
     }
   }
 }
 
+}  // namespace
+
+// ES6 section 20.2.2.10 Math.ceil ( x )
+void Builtins::Generate_MathCeil(compiler::CodeStubAssembler* assembler) {
+  Generate_MathRoundingOperation(assembler,
+                                 &compiler::CodeStubAssembler::Float64Ceil);
+}
+
+// ES6 section 20.2.2.16 Math.floor ( x )
+void Builtins::Generate_MathFloor(compiler::CodeStubAssembler* assembler) {
+  Generate_MathRoundingOperation(assembler,
+                                 &compiler::CodeStubAssembler::Float64Floor);
+}
+
 // ES6 section 20.2.2.17 Math.fround ( x )
 BUILTIN(MathFround) {
   HandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
   Handle<Object> x = args.at<Object>(1);
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, x, Object::ToNumber(x));
   float x32 = DoubleToFloat32(x->Number());
   return *isolate->factory()->NewNumber(x32);
 }
 
 // ES6 section 20.2.2.19 Math.imul ( x, y )
 BUILTIN(MathImul) {
   HandleScope scope(isolate);
   DCHECK_EQ(3, args.length());
   Handle<Object> x = args.at<Object>(1);
   Handle<Object> y = args.at<Object>(2);
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, x, Object::ToNumber(x));
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, y, Object::ToNumber(y));
   int product = static_cast<int>(NumberToUint32(*x) * NumberToUint32(*y));
   return *isolate->factory()->NewNumberFromInt(product);
 }
 
+// ES6 section 20.2.2.28 Math.round ( x )
+void Builtins::Generate_MathRound(compiler::CodeStubAssembler* assembler) {
+  Generate_MathRoundingOperation(assembler,
+                                 &compiler::CodeStubAssembler::Float64Round);
+}
+
 // ES6 section 20.2.2.32 Math.sqrt ( x )
 void Builtins::Generate_MathSqrt(compiler::CodeStubAssembler* assembler) {
   using compiler::Node;
 
   Node* x = assembler->Parameter(1);
   Node* context = assembler->Parameter(4);
   Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
   Node* value = assembler->Float64Sqrt(x_value);
   Node* result = assembler->ChangeFloat64ToTagged(value);
   assembler->Return(result);
 }
 
+// ES6 section 20.2.2.35 Math.trunc ( x )
+void Builtins::Generate_MathTrunc(compiler::CodeStubAssembler* assembler) {
+  Generate_MathRoundingOperation(assembler,
+                                 &compiler::CodeStubAssembler::Float64Trunc);
+}
+
 // -----------------------------------------------------------------------------
 // ES6 section 26.1 The Reflect Object
 
 
 // ES6 section 26.1.3 Reflect.defineProperty
 BUILTIN(ReflectDefineProperty) {
   HandleScope scope(isolate);
   DCHECK_EQ(4, args.length());
   Handle<Object> target = args.at<Object>(1);
   Handle<Object> key = args.at<Object>(2);
@@ skipping 2520 matching lines @@
 BUILTIN_LIST_T(DEFINE_BUILTIN_ACCESSOR_T)
 BUILTIN_LIST_H(DEFINE_BUILTIN_ACCESSOR_H)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 #undef DEFINE_BUILTIN_ACCESSOR_T
 #undef DEFINE_BUILTIN_ACCESSOR_H
 
 }  // namespace internal
 }  // namespace v8