[AArch64] Runtime-unroll small multi-exit loops on Apple Silicon. #10114
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…lvm#124462) Add an extra knob to RuntimeUnrollMultiExit to let backends control whether to allow multi-exit unrolling on a per-loop basis. This gives backends more fine-grained control on deciding if multi-exit unrolling is profitable for a given loop and uarch. Similar to 4226e0a. PR: llvm#124462 (cherry picked from commit ad9da92)
Test coverage to llvm#124751.
Extend unrolling preferences to allow more aggressive unrolling of search loops with 2 exits, building on the TTI hook added in ad9da92. In combination with eac23a5 this enables unrolling loops like std::find, which can improve performance significantly (+15% end-to-end on a workload that makes heavy use of std::find). It increase the total number of unrolled loops by ~2.5% across a very large corpus of workloads.
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@swift-ci please test |
fhahn
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Mar 2, 2025
[ValueTracking] AllowEphemerals for alignment assumptions. Follow up to pick change missed in #10114 to be able to analyze more loops with early exits.
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Extend unrolling preferences to allow more aggressive unrolling of
search loops with 2 exits, building on the TTI hook added in
ad9da92.
In combination with eac23a5 this enables unrolling loops like
std::find, which can improve performance significantly (+15% end-to-end
on a workload that makes heavy use of std::find). It increase the total
number of unrolled loops by ~2.5% across a very large corpus of
workloads.
(cherry-picked from llvm@46a13a5)
rdar://72436671