diff options
Diffstat (limited to 'home/math.asm')
| -rw-r--r-- | home/math.asm | 65 |
1 files changed, 25 insertions, 40 deletions
diff --git a/home/math.asm b/home/math.asm index c320fd15..1be69c33 100644 --- a/home/math.asm +++ b/home/math.asm @@ -1,86 +1,71 @@ -AddNTimes:: ; 0x30fe -; Add bc * a to hl. +SkipNames:: + ld bc, $b and a ret z -.loop +.asm_319e add hl, bc dec a - jr nz, .loop + jr nz, .asm_319e ret -; 0x3105 -SimpleMultiply:: ; 3105 -; Return a * c. +AddNTimes:: ; 31a3 (0:31a3) and a ret z +.asm_31a5 + add hl, bc + dec a + jr nz, .asm_31a5 + ret +SimpleMultiply:: + and a + ret z push bc ld b, a xor a -.loop +.asm_31af add c dec b - jr nz, .loop + jr nz, .asm_31af pop bc ret -; 3110 - -SimpleDivide:: ; 3110 -; Divide a by c. Return quotient b and remainder a. - ld b, 0 -.loop +SimpleDivide:: ; 31b5 (0:31b5) + ld b, $0 +.asm_31b7 inc b sub c - jr nc, .loop + jr nc, .asm_31b7 dec b add c ret -; 3119 - -Multiply:: ; 3119 -; Multiply hMultiplicand (3 bytes) by hMultiplier. Result in hProduct. -; All values are big endian. +Multiply:: push hl push bc - callab _Multiply + callab Multiply_ ; 1:67bd pop bc pop hl ret -; 3124 - -Divide:: ; 3124 -; Divide hDividend length b (max 4 bytes) by hDivisor. Result in hQuotient. -; All values are big endian. +Divide:: push hl push de push bc - ld a, [hROMBank] - push af - ld a, BANK(_Divide) - rst Bankswitch - call _Divide + homecall Divide_ ; 1:681d - pop af - rst Bankswitch pop bc pop de pop hl ret -; 3136 - -SubtractSigned:: ; 3136 -; Return a - b, sign in carry. +SubtractSigned:: sub b ret nc cpl - add 1 + add $1 scf ret -; 313d |