[MarcZX10]

What

Fold the current lane’s s_wqm bit to true for the supported pixel shader pattern, allowing the constant folder to remove the pixel ancillary select chain. Regression cases ensure unsupported patterns remain unchanged. This carries the fix for #2548; the original commit author is preserved.

Tested

• Linux GCC Release/Ninja: built pixel_ancillary_tests.
• CTest pixel_ancillary passed (1/1) on the rebased commit.

Checklist

• Based on current main
• One topic per PR
• No new third-party code
• Depends on: none
• AI-assisted: yes

Provenance: carries ThatsLeo’s fix from #2548; the commit author remains ThatsLeo.

[MarcZX10]

Linux validation report: pixel_ancillary_tests built successfully with GCC 12.2 / Ninja in Release mode, and CTest pixel_ancillary passed (1/1) on the latest rebased commit. This validates the positive and negative cases in the suite; I did not run a game or PS5 hardware test.

[github-actions]

Other open pull requests touch the same code. Merging one will break the other, or both implement the same thing. If this one builds on them, list them in Depends on.

Pull request	Conflicting files (lines on main)	Same exports	Same new files
#3891	core/shader/recompiler/Optimization/src/ConstantFolder.cpp L655-656
#4031	core/libs/tests/PixelAncillary.cpp L429, L478
#4156	core/shader/recompiler/Optimization/src/ConstantFolder.cpp L655-656

[MarcZX10]

The earlier conventions failure is superseded by the successful run on the current head. The latest conventions, eligibility, intake, relinker and register-context checks pass; the full Linux and Windows jobs are skipped by repository policy.

[MarcZX10]

I checked the current checks on this PR after the earlier failure report. The latest conventions run and all current required checks pass; the failure shown in the older check attempt was superseded. The shader regression test was reported passing on the current PR head.