X64: replace explicit zero-extend with runtime assert

src/compiler/x64/code-generator-x64.cc

 // 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.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties-inl.h"
@@ skipping 399 matching lines @@
     case kSSECvtsd2ss:
       __ cvtsd2ss(i.OutputDoubleRegister(), i.InputDoubleRegister(0));
       break;
     case kSSEFloat64ToInt32:
       if (instr->InputAt(0)->IsDoubleRegister()) {
         __ cvttsd2si(i.OutputRegister(), i.InputDoubleRegister(0));
       } else {
         __ cvttsd2si(i.OutputRegister(), i.InputOperand(0));
       }
       break;
-    case kSSEFloat64ToUint32:
+    case kSSEFloat64ToUint32: {
       if (instr->InputAt(0)->IsDoubleRegister()) {
         __ cvttsd2siq(i.OutputRegister(), i.InputDoubleRegister(0));
       } else {
         __ cvttsd2siq(i.OutputRegister(), i.InputOperand(0));
       }
-      __ andl(i.OutputRegister(), i.OutputRegister());  // clear upper bits.
-      // TODO(turbofan): generated code should not look at the upper 32 bits
-      // of the result, but those bits could escape to the outside world.
+      __ AssertZeroExtended(i.OutputRegister());
       break;
+    }
     case kSSEInt32ToFloat64:
       if (instr->InputAt(0)->IsRegister()) {
         __ cvtlsi2sd(i.OutputDoubleRegister(), i.InputRegister(0));
       } else {
         __ cvtlsi2sd(i.OutputDoubleRegister(), i.InputOperand(0));
       }
       break;
     case kSSEUint32ToFloat64:
       if (instr->InputAt(0)->IsRegister()) {
         __ cvtqsi2sd(i.OutputDoubleRegister(), i.InputRegister(0));
@@ skipping 549 matching lines @@
     }
   }
   MarkLazyDeoptSite();
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace compiler
 }  // namespace v8