X64: Count operations (increment, decrement)

src/x64/register-allocator-x64.cc

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@@ skipping 53 matching lines @@
   } else if (is_register() && reg().is(target)) {
     ASSERT(CodeGeneratorScope::Current()->has_valid_frame());
     CodeGeneratorScope::Current()->frame()->Spill(target);
     ASSERT(CodeGeneratorScope::Current()->allocator()->count(target) == 1);
   }
   ASSERT(is_register());
   ASSERT(reg().is(target));
 }
 
 
+// -------------------------------------------------------------------------
+// RegisterAllocator implementation.
+
+Result RegisterAllocator::AllocateByteRegisterWithoutSpilling() {
+  // X64 has no distinction between registers that can be used as 8-bit
+  // and registers that can't. However, if the register is not one of
+  // AL, CL, DL or BL, the REX.W bit is necessary to trigger 64-bit

[William Hesse, 2009/06/25 10:46:05]

We really don't even need this function anymore.  It is misleading, at best.

+  // interpretation of 8-bit registers (using SPL, BPL, DIL and SIL
+  // instead of AH, CH, DH and BH).
+  return AllocateWithoutSpilling();
+}
+
+
 } }  // namespace v8::internal