[wasm] Fixed float-to-int conversion tests.

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

Index: src/compiler/x64/code-generator-x64.cc
diff --git a/src/compiler/x64/code-generator-x64.cc b/src/compiler/x64/code-generator-x64.cc
index c07a21f8638314fa16bbd93c5eada9e8530036b7..3459acbb822a792502e0a7824ea1f8f51da9e8e4 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -1053,7 +1053,6 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       } else {
         __ Cvttss2siq(i.OutputRegister(), i.InputOperand(0));
       }
-      __ AssertZeroExtended(i.OutputRegister());
       break;
     }
     case kSSEFloat64Cmp:
@@ -1152,7 +1151,9 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       } else {
         __ Cvttsd2siq(i.OutputRegister(), i.InputOperand(0));
       }
-      __ AssertZeroExtended(i.OutputRegister());
+      if (MiscField::decode(instr->opcode())) {
+        __ AssertZeroExtended(i.OutputRegister());
+      }
       break;
     }
     case kSSEFloat32ToInt64: