[llvm] [VectorCombine] Fold insert(binop(x,y),binop(a,b),idx) --> binop(insert(x,a,idx),insert(x,a,idx)) (PR #124909)

[David Green via llvm-commits]

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@@ -738,6 +739,64 @@ bool VectorCombine::foldInsExtFNeg(Instruction &I) {
   return true;
 }
 
+/// Try to fold insert(binop(x,y),binop(a,b),idx)
+///         --> binop(insert(x,a,idx),insert(x,a,idx))
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davemgreen wrote:

Should this be `binop(insert(x,a,idx),insert(y,b,idx))`?

https://github.com/llvm/llvm-project/pull/124909