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[X86] Add a generic 32-bit CPU with sse2 with modern tuning flags to be used as the default for the 32-bit targets instead of pentium4
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Authored by craig.topper on Jul 15 2020, 11:39 AM.

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Summary

Currently our default 32-bit CPU on Linux and Windows is "pentium4" which comes with pentium4 tuning settings and almost non-existent scheduler.

This patch proposes to add a 32-bit CPU with sse2, but with more modern tuning settings to replace the default pentium4. I've chosen this way so that -march=pentium4 behavior doesn't change. Alternatively we can just change the pentium4 settings and assume no one cares about truly tuning for pentium4 these days.

This would be unnecessary if -mtune were supported, but this is a lot less effort than plumbing mtune.

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Event Timeline

craig.topper created this revision.Jul 15 2020, 11:39 AM
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Did you want to just change the pentium4 tuning? Otherwise naming things is hard and this feels awkward, but I don't have any better ideas :)

craig.topper abandoned this revision.Jul 17 2020, 12:22 PM