[x64] Emit vcvttsd2si[q] when AVX is enabled.

src/x64/macro-assembler-x64.h

Index: src/x64/macro-assembler-x64.h
diff --git a/src/x64/macro-assembler-x64.h b/src/x64/macro-assembler-x64.h
index b4da89c119f5a46957d9080ea7e695d3c351e9ec..c58abaec7c60f489f8fab2e380f22b882224036c 100644
--- a/src/x64/macro-assembler-x64.h
+++ b/src/x64/macro-assembler-x64.h
@@ -812,6 +812,11 @@ class MacroAssembler: public Assembler {
   void Cvtlsi2sd(XMMRegister dst, Register src);
   void Cvtlsi2sd(XMMRegister dst, const Operand& src);
 
+  void Cvttsd2si(Register dst, XMMRegister src);
+  void Cvttsd2si(Register dst, const Operand& src);
+  void Cvttsd2siq(Register dst, XMMRegister src);
+  void Cvttsd2siq(Register dst, const Operand& src);
+
   // Move if the registers are not identical.
   void Move(Register target, Register source);