[llvm] [InstCombine] Fold shuffles through all trivially vectorizable intrinsics (PR #141979)

[Nikita Popov via llvm-commits]

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@@ -1432,11 +1431,15 @@ InstCombinerImpl::foldShuffledIntrinsicOperands(IntrinsicInst *II) {
   // See if all arguments are shuffled with the same mask.
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nikic wrote:

Pre-existing, but the one use check above should be about the shuffle operands only, right? It doesn't help us if a constant argument is one-use (which it always is).

https://github.com/llvm/llvm-project/pull/141979