[PATCH] D144756: [SimplifyCFG] Do not hoist/sink convergent function calls

[Yaxun Liu via Phabricator via llvm-commits]

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Currently SimplifyCFG hoists/sink common instructions in then/else basic blocks
when certain options are enabled, which is the case for default clang optimization
pipelines for -O3. It tries to hoist/sink convergent function calls in divergent
control flow, which causes incorrect ISA generated for GPU, e.g.
 https://github.com/ROCm-Developer-Tools/HIP/issues/3172

This patch fixes that by conservatively disable hoisting/sinking common
convergent function calls in then/else blocks.


https://reviews.llvm.org/D144756

Files:
  llvm/lib/Transforms/Utils/SimplifyCFG.cpp
  llvm/test/Transforms/SimplifyCFG/convergent.ll

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