[llvm-dev] XOR A, A treatment (original) (raw)
James Courtier-Dutton via llvm-dev llvm-dev at lists.llvm.org
Thu Sep 27 03:50:06 PDT 2018
- Previous message: [llvm-dev] Coverage report. Clang-7.0.
- Next message: [llvm-dev] XOR A, A treatment
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Hi,
I am wondering about what suitable assembler level instruction substations are. For example: Result = XOR Reg1, Reg1;
Result is always zero, with the flags cleared. Could I substitute this for: Result = XOR Constant0, Constant0;
Thus freeing up Reg1 usage. I think this would be a valid substitution, but I wanted to check with the knowledgeable people on this list as to whether I am missing something important.
Other possible substitutions might be: Result = XOR Reg2, Reg2; Because it does not actually matter which reg is used.
Kind Regards
James -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180927/e68e4cd7/attachment.html>
- Previous message: [llvm-dev] Coverage report. Clang-7.0.
- Next message: [llvm-dev] XOR A, A treatment
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]