[PATCH] D25088: [x86] Fixing PR28755 by precomputing the address used in CMPXCHG8B

[Quentin Colombet via llvm-commits]

qcolombet added inline comments.


> aivchenk wrote in cmpxchg8b_alloca_regalloc_handling.ll:21
> You mean in the checks related to the first function? Well, I kinda wanted to express that the register that we are doing "lea" to is the same register we use for a memory location in cmpxchg8b. And since we don't hardcode the name of the register in EmitInstrWithCustomInserter, I did it as a regexp for esi/edi.
> 
> Although it makes me wonder whether it is valid or not to define/use regexp with the same name lower in the test

That's fine. My question was regarding the xor or mov. Why do we expect this to change?
We usually pick whatever codegen does, even if both are valid, so that we know when something change. That way we can check it was intended.

https://reviews.llvm.org/D25088