[PATCH] D128897: [SimplifyCFG] Improve SwitchToLookupTable optimization

[Alexander Shaposhnikov via Phabricator via llvm-commits]

alexander-shaposhnikov created this revision.
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Try to use the original value as an index (in the lookup table) in more cases
(to avoid one subtraction and actually shorten the dependency chain).
This addresses https://github.com/llvm/llvm-project/issues/56189

Test plan: ninja check-all


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D128897

Files:
  llvm/lib/Transforms/Utils/SimplifyCFG.cpp
  llvm/test/Transforms/SimplifyCFG/X86/switch_to_lookup_table.ll

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