Page MenuHomePhabricator

[DAGCombine][ARM] x ==/!= c -> (x - c) ==/!= 0 iff '-c' can be folded into the x node.
Needs ReviewPublic

Authored by lebedev.ri on May 25 2019, 10:23 AM.

Details

Summary

This fold, helps recover from the rest of the D62266 ARM regressions.
https://rise4fun.com/Alive/TvpC

Note that while the fold is quite flexible, i'we restricted it
to the single interesting pattern at the moment.

Diff Detail

Repository
rL LLVM

Event Timeline

lebedev.ri created this revision.May 25 2019, 10:23 AM
lebedev.ri retitled this revision from [DAGCombine] x ==/!= c -> (x - c) ==/!= 0 iff '-c' can be folded into the x node. to [DAGCombine][ARM] x ==/!= c -> (x - c) ==/!= 0 iff '-c' can be folded into the x node..May 25 2019, 11:49 AM

Can you add test coverage for some other target, maybe x86?

Can you add test coverage for a few more variations? Maybe something with SUBCARRY?