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

[Luke Lau 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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lukel97 wrote:

Good point, I went poking around though and it looks like constants don't return true for hasOneUse(). They seem to show up as 0 uses, so it happens to work today by coincidence.

Will fix anyway since I think with this patch we also need to worry about non-constant scalar args. 

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