Porting r9392 to x64 (smi-only arrays).

src/x64/ic-x64.cc

Index: src/x64/ic-x64.cc
diff --git a/src/x64/ic-x64.cc b/src/x64/ic-x64.cc
index 359b595a8dc329ad1f7b3d0137a89188ec2e2ae5..4541d23bceb1b0d4af3608d707e9431b5e73dedb 100644
--- a/src/x64/ic-x64.cc
+++ b/src/x64/ic-x64.cc
@@ -692,6 +692,20 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   // rax: value
   // rbx: receiver's elements array (a FixedArray)
   // rcx: index
+
+  if (FLAG_smi_only_arrays) {

[William Hesse, 2011/09/23 13:25:22]

The JumpIfNotSmi can be moved above the guard, together with the movq and ret
for the two smi cases (now made one case).  I think this speeds and simplifies
the code.

[Yang, 2011/09/23 14:19:12]

Done.

+    Label not_smi_only;
+    // Make sure the elements are smi-only.
+    __ movq(rdi, FieldOperand(rdx, HeapObject::kMapOffset));
+    __ CheckFastSmiOnlyElements(rdi, &not_smi_only, Label::kNear);
+    // Non-smis need to call into the runtime if the array is smi only.
+    __ JumpIfNotSmi(rax, &slow);
+    __ movq(FieldOperand(rbx, rcx, times_pointer_size, FixedArray::kHeaderSize),
+            rax);
+    __ ret(0);
+    __ bind(&not_smi_only);
+  }
+
   Label non_smi_value;
   __ movq(FieldOperand(rbx, rcx, times_pointer_size, FixedArray::kHeaderSize),
           rax);