microVU: Use uncached reg when clamping for FMAC instructions #4910
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Also fixes #4824 (confirmed by reporter). |
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Description of Changes
This was causing broken lighting in 64-bit mode, due to the larger number of registers available. Ft gets loaded and cached, but then the FMAC instructions clamp it in all modes except none, which disturbs the cached value (mismatched with the VU state). Jak happens to rely on this value not being clamped, so it was "okay" in 8-register mode because it had to be reloaded.
Rationale behind Changes
Broken rendering :)
Before:
After:
Suggested Testing Steps
Test tricky VU games in 64-bit mode. But this should be a relatively safe change I think, unless something was relying on the incorrect behaviour.