[llvm] [SimplifyCFG] Add optimization for switches of powers of two (PR #70977)

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,453 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool ./bin/opt --version 3
+; RUN: opt -passes='simplifycfg<switch-to-lookup>' -simplifycfg-require-and-preserve-domtree=1 -S -mtriple=riscv64 < %s \
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dtcxzyw wrote:

Please move this file to the `RISCV` subdirectory.

https://github.com/llvm/llvm-project/pull/70977