Fixed a number of issues on x64 crankshaft port:

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index b0cadda6d31a125117e063d8989e0438dd01d04e..4b4531eb689dbb5b78709a7ecede24e3b303c0dc 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -4627,10 +4627,10 @@ void ICCompareStub::GenerateSmis(MacroAssembler* masm) {
 
   if (GetCondition() == equal) {
     // For equality we do not care about the sign of the result.
-    __ SmiSub(rax, rax, rdx);
+    __ subq(rax, rdx);
   } else {
     NearLabel done;
-    __ SmiSub(rdx, rdx, rax);
+    __ subq(rdx, rax);
     __ j(no_overflow, &done);
     // Correct sign of result in case of overflow.
     __ SmiNot(rdx, rdx);