[llvm-commits] [llvm] r91104 - in /llvm/trunk/lib/Target/X86: X86InstrInfo.cpp X86InstrInfo.h

[Evan Cheng]

On Dec 12, 2009, at 10:40 AM, Evan Cheng wrote:

> 
> See 91105.
> 
> I had considered the issue of partial register stall. I do have a micro-benchmark that shows this patch speeding it up noticeably. Perhaps lea doesn't suffer from it? I'll fix up the test and commit it later.

Actually in 32-bit partial register stall does happen and makes it slower.

> 
> It might also be worthwhile to consider just using the 16-bit lea instruction. I'll experiment.

16-bit lea is indeed super slow.

Evan

> 
> Evan
> 
>> 
>> Dan
>> 
> 
> 
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits