llvm-project

4e44e876 - [X86] Add tests showing failure to concat fma chain which share concatenated operands (#173403)

[X86] Add tests showing failure to concat fma chain which share concatenated operands (#173403) We often have fma chains that reuse operands down the chain (e.g mathlib taylor series expansion) - FMA(FMA(X,Y,Z),X,W) etc. For these cases combineConcatVectorOps fails to account that the same operands will be concatenated down the recursion chain.