[llvm-dev] After InstCombine pass, expected output got changed

[Rohit Aggarwal via llvm-dev]

Hi All,

I am running the instcombine pass on the given lR and executing the binary.

*./build_release13x/bin/opt -enable-new-pm=false  -instcombine sample.ll -S
-o sample_instcombined_llvm.ll && ./build_release13x/bin/clang
sample_instcombined_llvm.ll && ./a.out*

But before passing to instcombine, the output is *CE6DB4AC* and after
passing to instcombine value changes to *3B83FBC*.

I tried to debug the issue and found that due to the occurence of poison
value, some instructions(or, store,..) are getting deleted/erased.

I also observed that there are active changes happening related to poison
values in the community. Is this behaviour expected one? Or Could it be a
side effect of those changes?

Thanks and Regards,
Rohit Aggarwal
Compiler Engineer - AMD

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