[wasm] Fix I32ReinterpretF32 and I64ReinterpretF64 on ia32.

src/compiler/instruction.h

 // 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.
 
 #ifndef V8_COMPILER_INSTRUCTION_H_
 #define V8_COMPILER_INSTRUCTION_H_
 
 #include <deque>
 #include <iosfwd>
 #include <map>
@@ skipping 1046 matching lines @@
     DCHECK_EQ(value_, static_cast<int64_t>(value));
     return value;
   }
 
   int64_t ToInt64() const {
     if (type() == kInt32) return ToInt32();
     DCHECK_EQ(kInt64, type());
     return value_;
   }
 
   float ToFloat32() const {

[titzer, 2017/01/19 13:13:01]

Maybe we should add a TODO to remove these methods, since they can cause the
signaling bit to be unset, as you've discovered. At least add a comment.

[ahaas, 2017/01/19 15:46:19]

Done.

     DCHECK_EQ(kFloat32, type());
     return bit_cast<float>(static_cast<int32_t>(value_));
   }
 
+  int32_t ToFloat32AsInt() const {
+    DCHECK_EQ(kFloat32, type());
+    return static_cast<int32_t>(value_);
+  }
+
   double ToFloat64() const {
     if (type() == kInt32) return ToInt32();
     DCHECK_EQ(kFloat64, type());
     return bit_cast<double>(value_);
   }
 
+  int64_t ToFloat64AsInt() const {
+    if (type() == kInt32) return ToInt32();
+    DCHECK_EQ(kFloat64, type());
+    return value_;
+  }
+
   ExternalReference ToExternalReference() const {
     DCHECK_EQ(kExternalReference, type());
     return bit_cast<ExternalReference>(static_cast<intptr_t>(value_));
   }
 
   RpoNumber ToRpoNumber() const {
     DCHECK_EQ(kRpoNumber, type());
     return RpoNumber::FromInt(static_cast<int>(value_));
   }
 
@@ skipping 521 matching lines @@
 };
 
 V8_EXPORT_PRIVATE std::ostream& operator<<(
     std::ostream& os, const PrintableInstructionSequence& code);
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_H_