llvm / llvm/llvm-project

LLVM doesn't seem to use BCAX when constants are involved

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#200,699 1 comment 2 reactions 0 assignees View on GitHub
backend:AArch64 missed-optimization
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LLVM
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Description

LLVM can emit BCAX when it's profitable if the values come from memory, but constant values appear to inhibit the emission of BCAX. Noticed this issue while optimizing RPCS3's SPU LLVM backend.

Here is a godbolt that reproduces the issue: https://godbolt.org/z/Yr1M478vP

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