[turbofan] Add operators for float32 support.

src/conversions.h

 // Copyright 2011 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_CONVERSIONS_H_
 #define V8_CONVERSIONS_H_
 
 #include <limits>
 
 #include "src/base/logging.h"
@@ skipping 59 matching lines @@
 
 
 inline double FastUI2D(unsigned x) {
   // There is no rounding involved in converting an unsigned integer to a
   // double, so this code should compile to a few instructions without
   // any FPU pipeline stalls.
   return static_cast<double>(x);
 }
 
 
+// This function should match the exact semantics of ECMA-262 20.2.2.17.
+inline float DoubleToFloat32(double x);
+
+
 // This function should match the exact semantics of ECMA-262 9.4.
 inline double DoubleToInteger(double x);
 
 
 // This function should match the exact semantics of ECMA-262 9.5.
 inline int32_t DoubleToInt32(double x);
 
 
 // This function should match the exact semantics of ECMA-262 9.6.
 inline uint32_t DoubleToUint32(double x) {
@@ skipping 140 matching lines @@
                            Object* number) {
   size_t result = 0;
   bool is_valid = TryNumberToSize(isolate, number, &result);
   CHECK(is_valid);
   return result;
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_CONVERSIONS_H_