mirror of https://github.com/pret/pokecrystal.git
77 lines
852 B
NASM
77 lines
852 B
NASM
SimpleMultiply: ; 3105
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; Return a * c.
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and a
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ret z
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push bc
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ld b, a
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xor a
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.loop
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add c
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dec b
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jr nz, .loop
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pop bc
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ret
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; 3110
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SimpleDivide: ; 3110
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; Divide a by c. Return quotient b and remainder a.
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ld b, 0
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.loop
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inc b
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sub c
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jr nc, .loop
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dec b
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add c
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ret
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; 3119
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Multiply: ; 3119
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; Multiply hMultiplicand (3 bytes) by hMultiplier. Result in hProduct.
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; All values are big endian.
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push hl
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push bc
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callab _Multiply
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pop bc
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pop hl
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ret
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; 3124
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Divide: ; 3124
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; Divide hDividend length b (max 4 bytes) by hDivisor. Result in hQuotient.
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; All values are big endian.
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push hl
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push de
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push bc
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ld a, [hROMBank]
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push af
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ld a, BANK(_Divide)
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rst Bankswitch
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call _Divide
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pop af
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rst Bankswitch
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pop bc
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pop de
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pop hl
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ret
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; 3136
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SubtractSigned: ; 3136
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; Return a - b, sign in carry.
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sub b
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ret nc
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cpl
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add 1
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scf
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ret
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; 313d
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