| commit | 6fd229a655f521a9f58d40c671e5cab4ea3ea87b | [log] [tgz] |
|---|---|---|
| author | Miguel Saldivar <miguel.saldivar@hpe.com> | Sat Oct 12 03:28:39 2024 -0700 |
| committer | GitHub <noreply@github.com> | Sat Oct 12 11:28:39 2024 +0100 |
| tree | b61d6492c96673e6e65737cd8a555e3115ec9d2a | |
| parent | b9cae45b63bc9c44521cc28b4a381afec6181f54 [diff] |
[X86] Invert (and X, ~(and ~Y, Z)) back into (and X, (or Y, ~Z)) (#109215)
When `andn` is available, we should avoid switching `s &= ~(z & ~y);` into `s &= ~z | y;`
This patch turns this assembly from:
```
foo:
not rcx
and rsi, rdx
andn rax, rsi, rdi
or rcx, rdx
and rax, rcx
ret
```
into:
```
foo:
and rsi, rdx
andn rcx, rdx, rcx
andn rax, rsi, rdi
andn rax, rcx, rax
ret
```
Fixes #108731
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