[PATCH] D126378: [SLP]Fix crash on reordering of ScatterVectorize nodes.

Tue Jun 21 15:59:13 PDT 2022

vdmitrie added a comment.

I guess the "crash" the patch suggested to fix looked like this:
llvm-project/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:8214: llvm::Value* llvm::slpvectorizer::BoUpSLP::vectorizeTree(llvm::slpvectorizer::BoUpSLP::ExtraValueToDebugLocsMap&): Assertion `Vec && "Can't find vectorizable value"' failed.

F23538352: reduced.ll <https://reviews.llvm.org/F23538352>

Please find a test case attached. It started to crash after this patch.

================
Comment at: llvm/test/Transforms/SLPVectorizer/X86/scatter-vectorize-reorder.ll:2
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -slp-vectorizer -mtriple=x86_64-unknown-linux-gnu -mcpu=cascadelake < %s | FileCheck %s
+
----------------
It seems the test does not actually execute the change. At this state it did not crash before the patch.
You probably wanted "skylake" here (i.e. an AVX2 with fast gather) instead of cascadelake . Otherwise TTI's forceScalarizeMaskedGather would return true and we really do not have any ScatterVectorize nodes in the tree.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D126378/new/

https://reviews.llvm.org/D126378