Fast sin/cos function for 68k Assembly

sincos.s

; Fast 68k sin/cos function
; -------------------------------------
; This is a sin/cos function suitable to be used inline as a macro for
; maximum speed, using a 256-byte lookup table.
; Provides simultaneous signed sin and cos values of an angle from 0-255.
; The return range is from -256 (0xff00) to 255 (0x00ff).
; This works especially well if your position, velocity, etc. are word values,
; where the high byte is the pixel value, and the low byte is the
; fractional/subpixel value.
; The macro version of this function takes 44 cycles and 10 memory reads.
; Use SINCOS a0 after loading SinTable into a0, or jump to sincos for the
; non-inline version which preserves address registers.
; -------------------------------------

; SINCOS \1
; Provides the sin and cos of d0 (assuming a 256-degree circle).
; \1: address register pointing to SinTable
; Returns: sin in d0, cos in d1 (word, range -256 to 255)
SINCOS  MACRO
        moveq     #64,d1
        add.b     d0,d1
        ext.w     d1
        ext.w     d0
        move.b    (\1,d1.w),d1
        move.b    (\1,d0.w),d0
        ENDM

        CODE
; Provides the sin and cos of d0 (assuming a 256-degree circle).
; Returns: sin in d0, cos in d1 (word, range -256 to 255)
sincos:
        move.l    a0,-(sp)
        lea       SinTable,a0
        SINCOS    a0
        move.l    (sp)+,a0
        rts

        DATA
SinTable = _SinTable+128
_SinTable:
;@generated-datagen-start----------------
; This code was generated by Amiga Assembly extension
;
;----- parameters : modify ------
;expression(x as variable): max(0, min(255, round(sin((x%256)*pi/128)*256) + 255 * round((x%256)/256)))
;variable:
;   name:x
;   startValue:128
;   endValue:383
;   step:1
;outputType(B,W,L): B
;outputInHex: true
;valuesPerLine: 8
;--------------------------------
;- DO NOT MODIFY following lines -
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        dc.b      $32, $2c, $26, $1f, $19, $13, $0d, $06
;@generated-datagen-end----------------