I had manually removed unused prefixes from CodeGen/X86 directory for more than 100 tests.
I checked the change history for each of them at the beginning, and then I mainly focused on the format since I found all of the unused prefixes were result from either insensible copy or residuum after functional update.
I think it's OK to remove the remaining X86 tests by script now. I wrote a rough script which works for me in most tests. I put it in llvm/utils temporarily for review and hope it may help other components owners.
The tests in this patch are all generated by the tool and checked by update tool for the autogenerated tests. I skimmed them and checked about 30 tests and didn't find any unexpected changes.
Reviewed By: mtrofin, MaskRay
Differential Revision: https://reviews.llvm.org/D91496
when the subtarget has fast strings.
This has two advantages:
- Speed is improved. For example, on Haswell thoughput improvements increase
linearly with size from 256 to 512 bytes, after which they plateau:
(e.g. 1% for 260 bytes, 25% for 400 bytes, 40% for 508 bytes).
- Code is much smaller (no need to handle boundaries).
llvm-svn: 300957
