Port code to load an integer directly from a heap number from ia32 to x64.

For now, this is a direct port from ia32, so there is probably still
stuff that can be improved here.
Review URL: http://codereview.chromium.org/555131

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3717 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/codegen-ia32.cc

@@ -7705,6 +7705,7 @@ void IntegerConvert(MacroAssembler* masm,
                     Register source,
                     bool use_sse3,
                     Label* conversion_failure) {
+  ASSERT(!source.is(ecx) && !source.is(edi) && !source.is(ebx));
   Label done, right_exponent, normal_exponent;
   Register scratch = ebx;
   Register scratch2 = edi;

src/x64/assembler-x64.cc

@@ -2113,6 +2113,16 @@ void Assembler::fisttp_s(const Operand& adr) {
 }
 
 
+void Assembler::fisttp_d(const Operand& adr) {
+  ASSERT(CpuFeatures::IsEnabled(SSE3));
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  emit_optional_rex_32(adr);
+  emit(0xDD);
+  emit_operand(1, adr);
+}
+
+
 void Assembler::fist_s(const Operand& adr) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;

src/x64/assembler-x64.h

@@ -1059,6 +1059,7 @@ class Assembler : public Malloced {
   void fistp_d(const Operand& adr);
 
   void fisttp_s(const Operand& adr);
+  void fisttp_d(const Operand& adr);
 
   void fabs();
   void fchs();