TF: Add ConvertFloat64ToUint32 and ConvertUint32ToFloat64 machine operators.

src/compiler/machine-operator.h

 // 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.
 
 #ifndef V8_COMPILER_MACHINE_OPERATOR_H_
 #define V8_COMPILER_MACHINE_OPERATOR_H_
 
 #include "src/compiler/opcodes.h"
 #include "src/compiler/operator.h"
 #include "src/zone.h"
@@ skipping 118 matching lines @@
   Operator* Int64Mul() { BINOP_AC(Int64Mul); }
   Operator* Int64Div() { BINOP(Int64Div); }
   Operator* Int64UDiv() { BINOP(Int64UDiv); }
   Operator* Int64Mod() { BINOP(Int64Mod); }
   Operator* Int64UMod() { BINOP(Int64UMod); }
   Operator* Int64LessThan() { BINOP(Int64LessThan); }
   Operator* Int64LessThanOrEqual() { BINOP(Int64LessThanOrEqual); }
 
   Operator* ConvertInt32ToInt64() { UNOP(ConvertInt32ToInt64); }
   Operator* ConvertInt64ToInt32() { UNOP(ConvertInt64ToInt32); }
+
+  // Convert representation of integers between float64 and int32/uint32.
+  // The precise rounding mode and handling of out of range inputs are *not*
+  // defined for these operators, since they are intended only for use with
+  // integers.
+  // TODO(titzer): rename ConvertXXX to ChangeXXX in machine operators.
   Operator* ConvertInt32ToFloat64() { UNOP(ConvertInt32ToFloat64); }
   Operator* ConvertUint32ToFloat64() { UNOP(ConvertUint32ToFloat64); }
-  // TODO(titzer): add rounding mode to floating point conversion.
   Operator* ConvertFloat64ToInt32() { UNOP(ConvertFloat64ToInt32); }
   Operator* ConvertFloat64ToUint32() { UNOP(ConvertFloat64ToUint32); }
 
-  // TODO(titzer): do we need different rounding modes for float arithmetic?
+  // Floating point operators always operate with IEEE 754 round-to-nearest.
   Operator* Float64Add() { BINOP_C(Float64Add); }
   Operator* Float64Sub() { BINOP(Float64Sub); }
   Operator* Float64Mul() { BINOP_C(Float64Mul); }
   Operator* Float64Div() { BINOP(Float64Div); }
   Operator* Float64Mod() { BINOP(Float64Mod); }
+
+  // Floating point comparisons complying to IEEE 754.
   Operator* Float64Equal() { BINOP_C(Float64Equal); }
   Operator* Float64LessThan() { BINOP(Float64LessThan); }
   Operator* Float64LessThanOrEqual() { BINOP(Float64LessThanOrEqual); }
 
   inline bool is32() const { return word_ == kMachineWord32; }
   inline bool is64() const { return word_ == kMachineWord64; }
   inline MachineRepresentation word() const { return word_; }
 
   static inline MachineRepresentation pointer_rep() {
     return kPointerSize == 8 ? kMachineWord64 : kMachineWord32;
   }
 
 #undef WORD_SIZE
 #undef UNOP
 #undef BINOP
 #undef OP1
 #undef SIMPLE
 
  private:
   Zone* zone_;
   MachineRepresentation word_;
 };
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_MACHINE_OPERATOR_H_