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`-mavx` should imply `-msse4.2` (or, implications between x86 CPU feature flags)
## Summary If a program is compiled with `-mavx`, the CPU running it should also support SSE4.2, thus GHC can emit `popcnt` instruction. More generally, GHC should have a better knowledge of implications between CPU features. As a note, LLVM's knowledge is written at: <https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/X86/X86.td> Maybe `SseVersion` in `compiler/GHC/Platform.hs` should include AVX family. ## Steps to reproduce ``` $ cat popcounttest.hs import Data.Bits {-# NOINLINE foo #-} foo :: Int -> Int foo x = 1 + popCount x main = print (foo 42) $ ghc -S -O2 -fforce-recomp popcounttest.hs $ grep -i popcnt popcounttest.s call hs_popcnt64 $ ghc -S -O2 -fforce-recomp -msse4.2 popcounttest.hs $ grep -i popcnt popcounttest.s popcnt %r14,%rax $ ghc -S -O2 -fforce-recomp -mavx popcounttest.hs $ grep -i popcnt popcounttest.s call hs_popcnt64 ``` ## Expected behavior GHC should emit `popcnt` when compiling with `-mavx`. ## Environment * GHC version used: 9.10.1 and 9.11.20240614 (ce76bf7851d4ec7a3ebd414a1991b3e71dfbc8c8) * Operating System: Ubuntu 22.04 * System Architecture: x86_64
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