X64: Adding macro to load double from memory, and use SSE3 instruction if present.

src/x64/assembler-x64.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2639 matching lines @@
   } else {
     emit(0x66);
     emit_optional_rex_32(dst, src);
     emit(0x0F);
     emit(0x28);
     emit_sse_operand(dst, src);
   }
 }
 
 
+void Assembler::movddup(XMMRegister dst, const Operand& src) {
+  ASSERT(CpuFeatures::IsEnabled(SSE3));
+  EnsureSpace ensure_space(this);
+  emit(0xF2);
+  emit_optional_rex_32(dst, src);
+  emit(0x0F);
+  emit(0x12);
+  emit_sse_operand(dst, src);
+}
+
+
 void Assembler::movss(XMMRegister dst, const Operand& src) {
   EnsureSpace ensure_space(this);
   emit(0xF3);  // single
   emit_optional_rex_32(dst, src);
   emit(0x0F);
   emit(0x10);  // load
   emit_sse_operand(dst, src);
 }
 
 
@@ skipping 362 matching lines @@
   // specially coded on x64 means that it is a relative 32 bit address, as used
   // by branch instructions.
   return (1 << rmode_) & kApplyMask;
 }
 
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64