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CLIP/CLIPw/CLIPLw read only the W component of their second operand. VCLSML, SCEA's standard macro library for VCL, uses the bare form `clipw.xyz a, b` in its PerformClipCheck macro, and 9 of the Tyra engine's 15 VU1 programs use that macro: https://github.com/h4570/tyra/blob/c59f406af134713b62656114846ac8d588c6247c/engine/src/renderer/3d/pipeline/shared/vcl_sml.i#L1393-L1398 Testing with SCE's vcl 1.4beta7 (the binary Tyra builds with) confirms that it compiles the bare form to the same instruction as `clipw.xyz a, b[w]` (`clipw.xyz VF01xyz,VF01w`), and that it also accepts `clipw a, b` as `.xyz`. openvcl required the explicit [w] and failed with "Invalid argument", so those 9 programs did not compile. The 'wcomp' template modifier now defaults a missing field to W, so the bare form emits exactly what [w] emits. Any other field is still rejected, as vcl 1.4beta7 ("instruction and operand have mismatching field select") and dvp-as ("bad instruction") both reject it. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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CLIP/CLIPw/CLIPLw read only the W component of their second operand. Tyra's VU programs use the VCLSML macro library, SCEA's standard macro library for VCL, which uses the bare form
clipw.xyz a, b. Testing with SCE's vcl 1.4beta7 (the binary Tyra builds with) confirms that it compiles to the same instruction asclipw.xyz a, b[w](clipw.xyz VF01xyz,VF01w), and that it also acceptsclipw a, bas.xyz. openvcl required the explicit[w]and failed with "Invalid argument", so 9 of Tyra's 15 VU1 programs did not compile. I've confirmed this with vcl 1.4beta7, from Tyra's repo (CI run).With this change, the
wcompoperand modifier now treats a missing field as W, so the bare form emits exactly the same instruction as[w]. Any other field is still rejected; dvp-as refuses those too (with "bad instruction").test/integration/test_clip_implicit_w.cpp: the bare and[w]forms produce identical output,clipw a, balso works, and[x]is rejected.