llvm-project

f73ed3d4 - [X86] lowerShuffleAsBroadcast - use isShuffleEquivalent to search for a hidden broadcast pattern (#126517)

[X86] lowerShuffleAsBroadcast - use isShuffleEquivalent to search for a hidden broadcast pattern (#126517) lowerShuffleAsBroadcast only matches a known-splat shuffle mask, but we can use the isShuffleEquivalent/IsElementEquivalent helpers to attempt to find a hidden broadcast-able shuffle pattern. This requires an extension to IsElementEquivalent to peek through bitcasts to match against wider shuffles - these typically appear during shuffle lowering where we've widened a preceding shuffle, often to a vector concatenation etc. Amazingly I hit this while yak shaving #126033 .......