[Bug tree-optimization/125442] Missed (x == 0) | ((x | y) == 0) to (x == 0)

[souradiptodas6 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125442

Souradipto Das <souradiptodas6 at gmail dot com> changed:

           What    |Removed                     |Added
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  Attachment #64567|0                           |1
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--- Comment #9 from Souradipto Das <souradiptodas6 at gmail dot com> ---
Created attachment 64568
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=64568&action=edit
v3 patch: Optimizes pattern by capturing and returning the entire comparison
subtree node (neeq@2) directly

Thanks for the guidance, Andrew! 

I've attached a v3 patch that updates the pattern to capture the comparison
node directly (`neeq@2`) and forward it, bypassing the need to reconstruct the
expression tree. 

Verified locally on x86_64-pc-linux-gnu; the testsuite still passes cleanly
with all 5 expected passes. Let me know if this looks good.