fix GetFontByStyle carry flag bug #708
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ZERICO2005
commented
Feb 11, 2026
Comment on lines
-2013
to
2015
| and a,c | ||
| cp a,c | ||
| ld c, (ix + strucFont.style) | ||
| ld a, (iy + arg5) | ||
| ; test for required set bits | ||
| and a, c | ||
| xor a, c | ||
| ret nz |
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and a, c makes it so a is less than or equal to c. Meaning that carry will be set if a does not equal c. Switching cp to xor fixes this (we only need to test for equality and don't need to preserve a)
ZERICO2005
commented
Feb 11, 2026
Comment on lines
-2018
to
-2020
| and a,c | ||
| xor a,c | ||
| cp a,c |
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Using the same trick of converting cp to xor to test for equality, we find that this becomes and a, c \ xor a, c \ xor a, c, which simplifies to and a, c
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Fixes
TODO: I think the CP here might sometimes SET carry when it shouldn't be?infontlibc_GetFontByStyleRaw