| Issue |
184061
|
| Summary |
[X86] Missed Fold: `x ^ vgf2p8affineqb(x, M)` => `vgf2p8affineqb(x, M ^ IDENTITY)`
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
WalterKruger
|
Extension of #178785. The standalone `x` can be interpreted as being affined by the identity matrix (`0x0102040810204080`), which allows it to be folded in the same manner. Only seems beneficial when the matrix is a constant.
```asm
xorWithRev_src:
vgf2p8affineqb xmm1, xmm0, xmmword ptr [rip + .LCPI0_0], 0
vpxor xmm0, xmm1, xmm0
ret
```
```asm
xorWithRev_tgt:
vgf2p8affineqb xmm0, xmm0, xmmword ptr [rip + .LCPI1_0], 0
ret
```
https://godbolt.org/z/nhhP4114G
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