[llvm] [MIPS]Remove unnecessary SLL instructions on MIPS64el (PR #109386)

[via llvm-commits]

anbbna wrote:

> > I don't think this transform is correct: https://alive2.llvm.org/ce/z/-kNt7y
> 
> I agree. You either need to call ComputeNumSignBits on the truncate input or do this transform instead:
> 
> ((signext (xor (trunc X), imm)) to (xor (signext_inreg X, i32), imm).

Thanks for your review. I will modify it to " (xor (signext_inreg X, i32), imm)"  based on your comments.

https://github.com/llvm/llvm-project/pull/109386