fix implementation of sqrt in freebios - #2720
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The sqrt SWI takes an unsigned integer, but subge/orrge perform signed comparisons. This means for any number >= 0x80000000, we perform incorrect arithmetic and the root gets forced to 0. This switches the instructions to perform unsigned comparisons.
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skimmed through the retail ntr arm9 bios and this looks like a correct fix |
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The sqrt SWI takes an unsigned integer, but subge/orrge perform signed comparisons. This means for any number >= 0x80000000, we perform incorrect arithmetic and the root gets forced to 0. This switches the instructions to perform unsigned comparisons.
An example of this bug can be observed in Rockman.EXE Operate Shooting Star, where if Rockman is on the furthest row from a Beetank, the Beetank's projectile will be aimed at itself rather than Rockman.
Before:
After:
