[turbofan] Support for %_DoubleHi, %_DoubleLo and %_ConstructDouble.

src/ia32/assembler-ia32.cc

Index: src/ia32/assembler-ia32.cc
diff --git a/src/ia32/assembler-ia32.cc b/src/ia32/assembler-ia32.cc
index 4be27ceeabaaec16394ce63a4965e8ed0f563a42..05d1bdd4f2178c73885a431aa5142ec276469d22 100644
--- a/src/ia32/assembler-ia32.cc
+++ b/src/ia32/assembler-ia32.cc
@@ -2217,6 +2217,24 @@ void Assembler::pcmpeqd(XMMRegister dst, XMMRegister src) {
 }
 
 
+void Assembler::punpckldq(XMMRegister dst, XMMRegister src) {
+  EnsureSpace ensure_space(this);
+  EMIT(0x66);
+  EMIT(0x0F);
+  EMIT(0x62);
+  emit_sse_operand(dst, src);
+}
+
+
+void Assembler::punpckhdq(XMMRegister dst, XMMRegister src) {
+  EnsureSpace ensure_space(this);
+  EMIT(0x66);
+  EMIT(0x0F);
+  EMIT(0x6A);
+  emit_sse_operand(dst, src);
+}
+
+
 void Assembler::cmpltsd(XMMRegister dst, XMMRegister src) {
   EnsureSpace ensure_space(this);
   EMIT(0xF2);