[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 782dba9fc4d228d163544db25d4f817434413123..2e4eccb48351dd787150711d9022009dff00b989 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -1059,7 +1059,6 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       } else {
         __ Cvttss2siq(i.OutputRegister(), i.InputOperand(0));
       }
-      __ AssertZeroExtended(i.OutputRegister());
       break;
     }
     case kSSEFloat64Cmp:
@@ -1158,7 +1157,9 @@ 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: