More targeted fix for gather instructions being slow on intel processors #7945
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vksnk
approved these changes
Nov 14, 2023
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gather being slow turned out to be a microcode mitigation on a range of intel processors
See llvm/llvm-project#70259
Rather than turn off SLP vectorization entirely as in #7918 , this PR just turns of gather instruction emission unless we know for sure we're not on one of the affected processors.
Fixes #7917 (but in a different way)