llvm-project

8efcfc24 - [SLP] Reuse diamond-matched gather across asymmetric reorder/reuse

[SLP] Reuse diamond-matched gather across asymmetric reorder/reuse processBuildVector's perfect-diamond match used Entries.front()->isSame( E->Scalars) only, missing matches where E carries the reorder/reuse and the entry is canonical. Two TreeEntries with the same effective scalar layout but different raw orderings then build independent gathers; one emits a fill-in shufflevector for reused lanes while the other leaves poison there. Fixes #194191. Reviewers: Pull Request: https://github.com/llvm/llvm-project/pull/194247