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Fix VU0 VCLIP semantics - #219

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GTTeancum wants to merge 1 commit into
ran-j:mainfrom
GTTeancum:fix/vu0-vclip-semantics
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Fix VU0 VCLIP semantics#219
GTTeancum wants to merge 1 commit into
ran-j:mainfrom
GTTeancum:fix/vu0-vclip-semantics

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Summary

  • implement VCLIP using the R5900/VU bit-level comparison rules
  • preserve the 24-bit history with positive/negative bits in hardware order
  • use �bs(Ft.w) and the hardware denormal threshold behavior
  • emit the shared helper from generated COP2 code
  • add generator and semantic regression tests

Why

The existing host-float comparison reverses each positive/negative flag pair and does not reproduce VU denormal handling. The incorrect clip flags broke Alchemy/Intrinsic Graphics frustum decisions in X-Men Legends.

Testing

  • VCLIP code-generation regression passes
  • positive/negative axis ordering passes
  • negative W and history preservation pass
  • denormal W threshold behavior passes
  • X-Men Legends proceeds through the affected Alchemy visibility path

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