[PATCH] D158642: LoopUnrollRuntime: Add branch weights to newly created branches

[Matthias Braun via Phabricator via llvm-commits]

MatzeB created this revision.
MatzeB added reviewers: wenlei, davidxl, hoy, paulkirth, dnovillo, mtrofin.
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Make sure every conditional branch constructed by `LoopUnrollRuntime` code sets branch weights.

- Add new 1:127 weights for the conditional jumps checking whether the whole (unrolled) loop should be skipped in the generated prolog or epilog code.
- Remove `updateLatchBranchWeightsForRemainderLoop` function and just add weights immediately when constructing the relevant branches. This leads to simpler code and makes the code more obvious as every call to `CreateCondBr` now has a `BranchWeights` parameter.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D158642

Files:
  llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp
  llvm/test/Transforms/LoopUnroll/runtime-exit-phi-scev-invalidation.ll
  llvm/test/Transforms/LoopUnroll/runtime-loop.ll
  llvm/test/Transforms/LoopUnroll/unroll-heuristics-pgo.ll

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