[PATCH] D99569: [AArch64][SVE] Fix vectoriser bug where predicated stores were dropped

[Joe Ellis via Phabricator via llvm-commits]

joechrisellis created this revision.
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This commit fixes a bug where loop vectoriser interleaving made an
invalid transform with SVE.

Code such as:

  1	void foo(int *restrict data1, int *restrict data2)
  2	{
  3	  int counter = 1024;
  4	  while (counter--)
  5	    if (data1[counter] > data2[counter])
  6	      data1[counter] = data2[counter];
  7	}

... was previously transformed in such a way that the predicated store
implied by:

  if (data1[counter] > data2[counter])

... was lost, resulting in bad codegen.

This bug was causing of some tests in llvm-test-suite to fail when built
for SVE.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D99569

Files:
  llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
  llvm/test/Transforms/LoopVectorize/AArch64/scalarize-store-with-predication.ll

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