X64: Abstract indexing by a smi to the macro assembler.

src/x64/stub-cache-x64.cc

Index: src/x64/stub-cache-x64.cc
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index a9433b4f77e6659ed0c0eaeb937677a23f66eba7..6642a14f5265899759bc0b9bcbf45477b1304db4 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -51,13 +51,14 @@ static void ProbeTable(MacroAssembler* masm,
   Label miss;
 
   __ movq(kScratchRegister, key_offset);
+  SmiIndex index = masm->SmiToIndex(offset, offset, kPointerSizeLog2);
   // Check that the key in the entry matches the name.
-  __ cmpl(name, Operand(kScratchRegister, offset, times_4, 0));
+  __ cmpl(name, Operand(kScratchRegister, index.reg, index.scale, 0));

[William Hesse, 2009/09/15 10:12:09]

Document that offset must be zero-extended in the calling context of ProbeTable,
or fix it here.

[Lasse Reichstein, 2009/09/15 10:39:08]

Fixed in SmiToIndex instead. 
I'll document that offset must be a positive smi.

   __ j(not_equal, &miss);
   // Get the code entry from the cache.
   // Use key_offset + kPointerSize, rather than loading value_offset.
   __ movq(kScratchRegister,
-          Operand(kScratchRegister, offset, times_4, kPointerSize));
+          Operand(kScratchRegister, index.reg, index.scale, kPointerSize));
   // Check that the flags match what we're looking for.
   __ movl(offset, FieldOperand(kScratchRegister, Code::kFlagsOffset));
   __ and_(offset, Immediate(~Code::kFlagsNotUsedInLookup));