| 1 |
88 |
robfinch |
code
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| 2 |
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;==============================================================================
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| 3 |
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; Decimal-Floating point to string conversion routine.
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| 4 |
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;
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| 5 |
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; Modifies
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| 6 |
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; _fpWork work area
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| 7 |
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; Register Usage:
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| 8 |
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; fp0 = input decimal-float to convert
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| 9 |
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; fp1 = constant holder, 1.0, 10.0
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| 10 |
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; fp2 = 1.0e value for conversion
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| 11 |
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; fp3 = holds digit value during significand conversion
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| 12 |
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; a0 = pointer to string buffer, updated to point to NULL at end of string
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| 13 |
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; a1 = pointer to "Nan" or "Inf" message string
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| 14 |
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; d0 = temporary
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| 15 |
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; d1 = digit value during exponent, significand conversion
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| 16 |
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; d6 = exponent
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| 17 |
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;==============================================================================
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| 18 |
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align 4
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| 19 |
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_dfOne dc.l $25ff0000,$00000000,$00000000
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| 20 |
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_dfTen dc.l $2600C000,$00000000,$00000000
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| 21 |
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_dfMil dc.l $2606DDFA,$1C000000,$00000000
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| 22 |
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| 23 |
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_msgNan dc.b "NaN",0
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| 24 |
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_msgInf dc.b "Inf",0
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| 25 |
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even
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| 26 |
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| 27 |
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;------------------------------------------------------------------------------
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| 28 |
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; Check for the special Nan and infinity values. Output the appropriate string.
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| 29 |
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;
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| 30 |
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; Modifies
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| 31 |
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; _fpWork area
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| 32 |
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; a0
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| 33 |
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; Parameters:
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| 34 |
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; fp0 = dbl
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| 35 |
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;------------------------------------------------------------------------------
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| 36 |
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| 37 |
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_CheckNan:
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| 38 |
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link a2,#-12
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| 39 |
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movem.l d0/a1,(sp)
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| 40 |
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move.l _canary,8(sp)
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| 41 |
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fmove.x fp0,_fpWork
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| 42 |
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move.b _fpWork,d0 ; get sign+combo
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| 43 |
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andi.b #$7C,d0 ; mask for combo bits
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| 44 |
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cmpi.b #$7C,d0 ; is it the Nan combo?
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| 45 |
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bne .notNan
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| 46 |
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lea _msgNan,a1 ; output "Nan"
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| 47 |
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bra .outStr
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| 48 |
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.notNan
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| 49 |
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cmpi.b #$78,d0 ; is it infinity combo?
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| 50 |
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bne .notInf
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| 51 |
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lea _msgInf,a1
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| 52 |
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.outStr
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| 53 |
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move.b (a1)+,(a0)+ ; output "Inf"
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| 54 |
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move.b (a1)+,(a0)+
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| 55 |
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move.b (a1)+,(a0)+
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| 56 |
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clr.b (a0)
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| 57 |
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movem.l (sp),d0/a1
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| 58 |
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cchk 8(sp)
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| 59 |
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unlk a2
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| 60 |
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ori #1,ccr ; set carry and return
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| 61 |
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rts
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| 62 |
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.notInf
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| 63 |
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movem.l (sp),d0/a1
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| 64 |
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cchk 8(sp)
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| 65 |
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unlk a2
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| 66 |
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andi #$FE,ccr ; clear carry and return
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| 67 |
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rts
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| 68 |
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| 69 |
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;------------------------------------------------------------------------------
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| 70 |
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; Check for a zero value. Output a single "0" if zero,
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| 71 |
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;
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| 72 |
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; Modifies:
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| 73 |
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; a0
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| 74 |
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; Parameters:
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| 75 |
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; fp0 = dbl
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| 76 |
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;------------------------------------------------------------------------------
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| 77 |
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| 78 |
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_CheckZero:
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| 79 |
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ftst fp0 ; check if number is zero
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| 80 |
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fbne .0003
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| 81 |
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move.b #'0',(a0)+ ; if zero output "0"
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| 82 |
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clr.b (a0)
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| 83 |
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ori #4,ccr ; set zf
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| 84 |
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rts
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| 85 |
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.0003
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| 86 |
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andi #$FB,ccr ; clear zf
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| 87 |
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rts
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| 88 |
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| 89 |
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;------------------------------------------------------------------------------
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| 90 |
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; Check for a negative number. This includes Nans and Infinities. Output a "-"
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| 91 |
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; if negative.
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| 92 |
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;
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| 93 |
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; Modifies
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| 94 |
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; a0
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| 95 |
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; Parameters:
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| 96 |
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; fp0 = dbl
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| 97 |
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;------------------------------------------------------------------------------
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| 98 |
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| 99 |
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_CheckNegative:
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| 100 |
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ftst fp0 ; is number negative?
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| 101 |
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fbge .0002
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| 102 |
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move.b #'-',(a0)+ ; yes, output '-'
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| 103 |
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fneg fp0 ; make fp0 positive
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| 104 |
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.0002
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| 105 |
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rts
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| 106 |
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| 107 |
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;------------------------------------------------------------------------------
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| 108 |
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; Make the input value larger so that digits may appear before the decimal
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| 109 |
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; point.
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| 110 |
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;
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| 111 |
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; Modifies:
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| 112 |
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; fp0,fp1,d6
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| 113 |
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; Parameters:
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| 114 |
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; fp0 = dbl
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| 115 |
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;------------------------------------------------------------------------------
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| 116 |
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| 117 |
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; if (dbl < 1.0) {
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| 118 |
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; while (dbl < 1.0) {
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| 119 |
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; dbl *= 1000000.0;
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| 120 |
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; exp -= 6;
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| 121 |
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; }
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| 122 |
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; }
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| 123 |
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| 124 |
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_MakeBig:
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| 125 |
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fmove.w #1,fp1
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| 126 |
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.0002
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| 127 |
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fcmp fp1,fp0 ; is fp0 > 1?
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| 128 |
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fbge .0001 ; yes, return
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| 129 |
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fscale.l #6,fp0 ; multiply fp0 by a million
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| 130 |
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subi.w #6,d6 ; decrement exponent by six
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| 131 |
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bra .0002 ; keep trying until number is > 1
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| 132 |
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.0001
|
| 133 |
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rts
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| 134 |
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| 135 |
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;------------------------------------------------------------------------------
|
| 136 |
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; Create a number dbl2 on the same order of magnitude as dbl, but
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| 137 |
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; less than dbl. The number will be 1.0e
|
| 138 |
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;
|
| 139 |
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; Modifies:
|
| 140 |
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; d6,fp2
|
| 141 |
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; Parameters:
|
| 142 |
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; fp0 = dbl
|
| 143 |
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;------------------------------------------------------------------------------
|
| 144 |
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| 145 |
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; // The following is similar to using log10() and pow() functions.
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| 146 |
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; // Now dbl is >= 1.0
|
| 147 |
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; // Create a number dbl2 on the same order of magnitude as dbl, but
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| 148 |
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; // less than dbl.
|
| 149 |
|
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; dbl2 = 1.0;
|
| 150 |
|
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; dbla = dbl2;
|
| 151 |
|
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; if (dbl > dbl2) { // dbl > 1.0 ?
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| 152 |
|
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; while (dbl2 <= dbl) {
|
| 153 |
|
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; dbla = dbl2;
|
| 154 |
|
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; dbl2 *= 10.0; // increase power of 10
|
| 155 |
|
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; exp++;
|
| 156 |
|
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; }
|
| 157 |
|
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; // The above loop goes one too far, we want the last value less
|
| 158 |
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; // than dbl.
|
| 159 |
|
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; dbl2 = dbla;
|
| 160 |
|
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; exp--;
|
| 161 |
|
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; }
|
| 162 |
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| 163 |
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_LessThanDbl:
|
| 164 |
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fmove.w #1,fp2 ; setup fp2 = 1
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| 165 |
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fcmp fp2,fp0 ; if (dbl > dbl2)
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| 166 |
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fble .0004
|
| 167 |
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.0006
|
| 168 |
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fcmp fp0,fp2 ; while (dbl2 <= dbl)
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| 169 |
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fbgt .0005
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| 170 |
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fscale.w #1,fp2 ; dbl2 *= 10 (increase exponent by one)
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| 171 |
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addi.w #1,d6 ; exp++
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| 172 |
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bra .0006
|
| 173 |
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.0005
|
| 174 |
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fscale.l #-1,fp2 ; dbl2 /= 10 (decrease exponent by one)
|
| 175 |
|
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subi.w #1,d6 ; exp--;
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| 176 |
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.0004
|
| 177 |
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; fmove.x fp0,_fpWork ; debugging
|
| 178 |
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; fmove.x fp2,_fpWork+12
|
| 179 |
|
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rts
|
| 180 |
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| 181 |
|
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;------------------------------------------------------------------------------
|
| 182 |
|
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; Compute the number of digits before the decimal point.
|
| 183 |
|
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;
|
| 184 |
|
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; Modifies:
|
| 185 |
|
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; d0,d6,_digits_before_decpt
|
| 186 |
|
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; Parameters:
|
| 187 |
|
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; d6 = exponent
|
| 188 |
|
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;------------------------------------------------------------------------------
|
| 189 |
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| 190 |
|
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; if (exp >= 0 && exp < 6) {
|
| 191 |
|
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; digits_before_decpt = exp+1;
|
| 192 |
|
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; exp = 0;
|
| 193 |
|
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; }
|
| 194 |
|
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; else if (exp >= -7)
|
| 195 |
|
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; digits_before_decpt = 1;
|
| 196 |
|
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; else
|
| 197 |
|
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; digits_before_decpt = -1;
|
| 198 |
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| 199 |
|
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_ComputeDigitsBeforeDecpt:
|
| 200 |
|
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move.l d0,-(a7)
|
| 201 |
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tst.w d6
|
| 202 |
|
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bmi .0007
|
| 203 |
|
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cmpi.w #6,d6
|
| 204 |
|
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bge .0007
|
| 205 |
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move.w d6,d0
|
| 206 |
|
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addi.w #1,d0
|
| 207 |
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move.w d0,_digits_before_decpt
|
| 208 |
|
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clr.w d6
|
| 209 |
|
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move.l (a7)+,d0
|
| 210 |
|
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rts
|
| 211 |
|
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.0007
|
| 212 |
|
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cmpi.w #-7,d6
|
| 213 |
|
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blt .0009
|
| 214 |
|
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move.w #1,_digits_before_decpt
|
| 215 |
|
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move.l (a7)+,d0
|
| 216 |
|
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rts
|
| 217 |
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.0009
|
| 218 |
|
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move.w #-1,_digits_before_decpt
|
| 219 |
|
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move.l (a7)+,d0
|
| 220 |
|
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rts
|
| 221 |
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|
| 222 |
|
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;------------------------------------------------------------------------------
|
| 223 |
|
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; Spit out a leading zero before the decimal point for a small number.
|
| 224 |
|
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;
|
| 225 |
|
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; Modifies:
|
| 226 |
|
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; a0
|
| 227 |
|
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; Parameters:
|
| 228 |
|
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; d6 = exponent
|
| 229 |
|
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;------------------------------------------------------------------------------
|
| 230 |
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| 231 |
|
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; if (exp < -7) {
|
| 232 |
|
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; buf[ndx] = '0';
|
| 233 |
|
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; ndx++;
|
| 234 |
|
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; buf[ndx] = '.';
|
| 235 |
|
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; ndx++;
|
| 236 |
|
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; }
|
| 237 |
|
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|
| 238 |
|
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_LeadingZero:
|
| 239 |
|
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cmpi.w #-7,d6
|
| 240 |
|
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bge .0010
|
| 241 |
|
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move.b #'0',(a0)+
|
| 242 |
|
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move.b #'.',(a0)+
|
| 243 |
|
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.0010
|
| 244 |
|
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rts
|
| 245 |
|
|
|
| 246 |
|
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;------------------------------------------------------------------------------
|
| 247 |
|
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; Extract the digits of the significand.
|
| 248 |
|
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;
|
| 249 |
|
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; Modifies:
|
| 250 |
|
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; _precision variable
|
| 251 |
|
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; Register Usage
|
| 252 |
|
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; d0 = counter
|
| 253 |
|
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; d1 = digit
|
| 254 |
|
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; fp0 = dbl
|
| 255 |
|
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; fp2 = dbl2
|
| 256 |
|
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; fp3 = digit as decimal float
|
| 257 |
|
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; fp7 = dbla
|
| 258 |
|
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; Parameters:
|
| 259 |
|
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; fp0, fp2
|
| 260 |
|
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;------------------------------------------------------------------------------
|
| 261 |
|
|
|
| 262 |
|
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; // Now loop processing one digit at a time.
|
| 263 |
|
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; for (nn = 0; nn < 25 && precision > 0; nn++) {
|
| 264 |
|
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; digit = 0;
|
| 265 |
|
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; dbla = dbl;
|
| 266 |
|
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; // dbl is on the same order of magnitude as dbl2 so
|
| 267 |
|
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; // a repeated subtract can be used to find the digit.
|
| 268 |
|
|
; while (dbl >= dbl2) {
|
| 269 |
|
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; dbl -= dbl2;
|
| 270 |
|
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; digit++;
|
| 271 |
|
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; }
|
| 272 |
|
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; buf[ndx] = digit + '0';
|
| 273 |
|
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; // Now go back and perform just a single subtract and
|
| 274 |
|
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; // a multiply to find out how much to reduce dbl by.
|
| 275 |
|
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; // This should improve the accuracy
|
| 276 |
|
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; if (digit > 2)
|
| 277 |
|
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; dbl = dbla - dbl2 * digit;
|
| 278 |
|
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; ndx++;
|
| 279 |
|
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; digits_before_decpt--;
|
| 280 |
|
|
; if (digits_before_decpt==0) {
|
| 281 |
|
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; buf[ndx] = '.';
|
| 282 |
|
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; ndx++;
|
| 283 |
|
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; }
|
| 284 |
|
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; else if (digits_before_decpt < 0)
|
| 285 |
|
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; precision--;
|
| 286 |
|
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; // Shift the next digit to be tested into position.
|
| 287 |
|
|
; dbl *= 10.0;
|
| 288 |
|
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; }
|
| 289 |
|
|
|
| 290 |
|
|
_SpitOutDigits:
|
| 291 |
|
|
link a2,#-24
|
| 292 |
|
|
move.l _canary,20(sp)
|
| 293 |
|
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fmove.x fp7,(sp)
|
| 294 |
|
|
movem.l d0/d1,12(sp)
|
| 295 |
|
|
move.w #24,d0 ; d0 = nn
|
| 296 |
|
|
.0017
|
| 297 |
|
|
tst.l _precision
|
| 298 |
|
|
ble .0011
|
| 299 |
|
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moveq #0,d1 ; digit = 0
|
| 300 |
|
|
fmove fp0,fp7 ; dbla = dbl
|
| 301 |
|
|
.0013
|
| 302 |
|
|
fcmp fp2,fp0
|
| 303 |
|
|
fblt .0012
|
| 304 |
|
|
fsub fp2,fp0 ; dbl -= dbl2
|
| 305 |
|
|
addi.b #1,d1 ; digit++
|
| 306 |
|
|
bra .0013
|
| 307 |
|
|
.0012
|
| 308 |
|
|
addi.b #'0',d1 ; convert digit to ascii
|
| 309 |
|
|
move.b d1,(a0)+ ; and store
|
| 310 |
|
|
subi.b #'0',d1 ; d1 = binary digit again
|
| 311 |
|
|
; cmpi.b #2,d1
|
| 312 |
|
|
; ble .0014
|
| 313 |
|
|
|
| 314 |
|
|
; ext.w d1
|
| 315 |
|
|
; ext.l d1
|
| 316 |
|
|
; fmove.l d1,fp3 ; fp3 = digit
|
| 317 |
|
|
; fmul fp2,fp3 ; fp3 = dbl2 * digit
|
| 318 |
|
|
; fmove fp7,fp0
|
| 319 |
|
|
; fsub fp3,fp0 ; dbl = dbla - dbl2 * digit
|
| 320 |
|
|
.0014
|
| 321 |
|
|
subi.w #1,_digits_before_decpt
|
| 322 |
|
|
bne .0015
|
| 323 |
|
|
move.b #'.',(a0)+
|
| 324 |
|
|
.0015
|
| 325 |
|
|
tst.w _digits_before_decpt
|
| 326 |
|
|
bge .0016
|
| 327 |
|
|
subi.l #1,_precision
|
| 328 |
|
|
.0016
|
| 329 |
|
|
fscale.l #-1,fp2 ; dbl *= 10.0
|
| 330 |
|
|
dbra d0,.0017
|
| 331 |
|
|
.0011
|
| 332 |
|
|
movem.l 12(sp),d0/d1
|
| 333 |
|
|
fmove.x (sp),fp7
|
| 334 |
|
|
cchk 20(sp)
|
| 335 |
|
|
unlk a2
|
| 336 |
|
|
rts
|
| 337 |
|
|
|
| 338 |
|
|
;------------------------------------------------------------------------------
|
| 339 |
|
|
; If the number ends in a decimal point, trim off the point.
|
| 340 |
|
|
;
|
| 341 |
|
|
; Registers Modified:
|
| 342 |
|
|
; none
|
| 343 |
|
|
; Parameters:
|
| 344 |
|
|
; a0 = pointer to end of number
|
| 345 |
|
|
; Returns:
|
| 346 |
|
|
; a0 = updated to point just past last digit.
|
| 347 |
|
|
;------------------------------------------------------------------------------
|
| 348 |
|
|
|
| 349 |
|
|
_TrimTrailingPoint:
|
| 350 |
|
|
cmpi.b #'.',-1(a0)
|
| 351 |
|
|
bne .0001
|
| 352 |
|
|
clr.b -(a0)
|
| 353 |
|
|
rts
|
| 354 |
|
|
.0001
|
| 355 |
|
|
cmpi.b #'.',(a0)
|
| 356 |
|
|
bne .0002
|
| 357 |
|
|
cmpi.b #0,1(a0)
|
| 358 |
|
|
bne .0002
|
| 359 |
|
|
clr.b (a0)
|
| 360 |
|
|
subq #1,a0
|
| 361 |
|
|
.0002
|
| 362 |
|
|
rts
|
| 363 |
|
|
|
| 364 |
|
|
;------------------------------------------------------------------------------
|
| 365 |
|
|
; If the number ends in .0 get rid of the .0
|
| 366 |
|
|
;
|
| 367 |
|
|
; Registers Modified:
|
| 368 |
|
|
; none
|
| 369 |
|
|
; Parameters:
|
| 370 |
|
|
; a0 = pointer to last digits of number
|
| 371 |
|
|
; Returns:
|
| 372 |
|
|
; a0 = updated to point just past last digit.
|
| 373 |
|
|
;------------------------------------------------------------------------------
|
| 374 |
|
|
|
| 375 |
|
|
_TrimDotZero:
|
| 376 |
|
|
tst.b (a0)
|
| 377 |
|
|
bne .0004
|
| 378 |
|
|
cmpi.b #'0',-1(a0)
|
| 379 |
|
|
bne .0004
|
| 380 |
|
|
cmpi.b #'.',-2(a0)
|
| 381 |
|
|
bne .0004
|
| 382 |
|
|
clr.b -2(a0)
|
| 383 |
|
|
subq #2,a0
|
| 384 |
|
|
.0004
|
| 385 |
|
|
rts
|
| 386 |
|
|
|
| 387 |
|
|
;------------------------------------------------------------------------------
|
| 388 |
|
|
; Trim trailing zeros from the number. Generally there is no need to display
|
| 389 |
|
|
; trailing zeros.
|
| 390 |
|
|
; Turns a number like 652.000000000000000000000 into 650.0
|
| 391 |
|
|
;
|
| 392 |
|
|
; Registers Modified:
|
| 393 |
|
|
; none
|
| 394 |
|
|
; Parameters:
|
| 395 |
|
|
; a0 = pointer to last digits of number
|
| 396 |
|
|
; Returns:
|
| 397 |
|
|
; a0 = updated to point just past last digit.
|
| 398 |
|
|
;------------------------------------------------------------------------------
|
| 399 |
|
|
|
| 400 |
|
|
; // Trim trailing zeros from the number
|
| 401 |
|
|
; do {
|
| 402 |
|
|
; ndx--;
|
| 403 |
|
|
; } while(buf[ndx]=='0');
|
| 404 |
|
|
; ndx++;
|
| 405 |
|
|
|
| 406 |
|
|
_TrimTrailingZeros:
|
| 407 |
|
|
.0018
|
| 408 |
|
|
cmpi.b #'0',-(a0) ; if the last digit was a zero, backup
|
| 409 |
|
|
beq .0018
|
| 410 |
|
|
addq #1,a0 ; now advance by one
|
| 411 |
|
|
move.b #0,(a0) ; NULL terminate string
|
| 412 |
|
|
rts
|
| 413 |
|
|
|
| 414 |
|
|
;------------------------------------------------------------------------------
|
| 415 |
|
|
; Output 'e+' or 'e-'
|
| 416 |
|
|
;
|
| 417 |
|
|
; Registers Modified:
|
| 418 |
|
|
; d6.w (if negative)
|
| 419 |
|
|
; Parameters:
|
| 420 |
|
|
; a0 = pointer to last digits of number
|
| 421 |
|
|
; Returns:
|
| 422 |
|
|
; a0 = updated to point just past '+' or '-'.
|
| 423 |
|
|
;------------------------------------------------------------------------------
|
| 424 |
|
|
|
| 425 |
|
|
; // Spit out +/-E
|
| 426 |
|
|
; buf[ndx] = E;
|
| 427 |
|
|
; ndx++;
|
| 428 |
|
|
; if (exp < 0) {
|
| 429 |
|
|
; buf[ndx]='-';
|
| 430 |
|
|
; ndx++;
|
| 431 |
|
|
; exp = -exp;
|
| 432 |
|
|
; }
|
| 433 |
|
|
; else {
|
| 434 |
|
|
; buf[ndx]='+';
|
| 435 |
|
|
; ndx++;
|
| 436 |
|
|
; }
|
| 437 |
|
|
|
| 438 |
|
|
_SpitOutE:
|
| 439 |
|
|
move.b _E,(a0)+
|
| 440 |
|
|
tst.w d6
|
| 441 |
|
|
bge .0021
|
| 442 |
|
|
move.b #'-',(a0)+
|
| 443 |
|
|
neg.w d6
|
| 444 |
|
|
bra .0022
|
| 445 |
|
|
.0021
|
| 446 |
|
|
move.b #'+',(a0)+
|
| 447 |
|
|
.0022
|
| 448 |
|
|
rts
|
| 449 |
|
|
|
| 450 |
|
|
;------------------------------------------------------------------------------
|
| 451 |
|
|
; Extract a single digit of the exponent. Extract works from the leftmost digit
|
| 452 |
|
|
; to the rightmost.
|
| 453 |
|
|
;
|
| 454 |
|
|
; Register Usage
|
| 455 |
|
|
; d2 = history of zeros
|
| 456 |
|
|
; d3 = digit
|
| 457 |
|
|
; Modifies
|
| 458 |
|
|
; d2,d6,a0
|
| 459 |
|
|
; Parameter
|
| 460 |
|
|
; d1.w = power of ten
|
| 461 |
|
|
; d6.w = exponent
|
| 462 |
|
|
;------------------------------------------------------------------------------
|
| 463 |
|
|
|
| 464 |
|
|
_ExtExpDigit:
|
| 465 |
|
|
move.l d3,-(a7)
|
| 466 |
|
|
ext.l d6 ; make d6 a long
|
| 467 |
|
|
divu d1,d6 ; divide by power of ten
|
| 468 |
|
|
move.b d6,d3 ; d3 = quotient (0 to 9)
|
| 469 |
|
|
swap d6 ; d6 = remainder, setup for next digit
|
| 470 |
|
|
or.b d3,d2
|
| 471 |
|
|
tst.b d3
|
| 472 |
|
|
bne .0003
|
| 473 |
|
|
tst.b d2
|
| 474 |
|
|
beq .0004
|
| 475 |
|
|
.0003
|
| 476 |
|
|
addi.b #'0',d3 ; convert to ascii
|
| 477 |
|
|
move.b d3,(a0)+
|
| 478 |
|
|
.0004
|
| 479 |
|
|
move.l (a7)+,d3
|
| 480 |
|
|
rts
|
| 481 |
|
|
|
| 482 |
|
|
;------------------------------------------------------------------------------
|
| 483 |
|
|
; Extract all the digits of the exponent.
|
| 484 |
|
|
;
|
| 485 |
|
|
; Register Usage
|
| 486 |
|
|
; d1 = power of 10
|
| 487 |
|
|
; d2 = history of zeros
|
| 488 |
|
|
; Parameters
|
| 489 |
|
|
; a0 = pointer to string buffer
|
| 490 |
|
|
; d6 = exponent
|
| 491 |
|
|
;------------------------------------------------------------------------------
|
| 492 |
|
|
|
| 493 |
|
|
; // If the number is times 10^0 don't output the exponent
|
| 494 |
|
|
; if (exp==0) {
|
| 495 |
|
|
; buf[ndx]='\0';
|
| 496 |
|
|
; goto prt;
|
| 497 |
|
|
; }
|
| 498 |
|
|
|
| 499 |
|
|
_ExtExpDigits:
|
| 500 |
|
|
move.l d1,-(a7)
|
| 501 |
|
|
tst.w d6 ; is exponent zero?
|
| 502 |
|
|
beq .0002
|
| 503 |
|
|
bsr _SpitOutE ; exponent is non-zero e+
|
| 504 |
|
|
clr.b d2 ; d2 = history of zeros
|
| 505 |
|
|
move.w #1000,d1
|
| 506 |
|
|
bsr _ExtExpDigit
|
| 507 |
|
|
move.w #100,d1
|
| 508 |
|
|
bsr _ExtExpDigit
|
| 509 |
|
|
move.w #10,d1
|
| 510 |
|
|
bsr _ExtExpDigit
|
| 511 |
|
|
move.w #1,d1
|
| 512 |
|
|
bsr _ExtExpDigit
|
| 513 |
|
|
.0002:
|
| 514 |
|
|
move.l (a7)+,d1
|
| 515 |
|
|
move.b #0,(a0) ; NULL terminate string
|
| 516 |
|
|
rts ; and return
|
| 517 |
|
|
|
| 518 |
|
|
;------------------------------------------------------------------------------
|
| 519 |
|
|
; Pad the left side of the output string.
|
| 520 |
|
|
;
|
| 521 |
|
|
; Modifies:
|
| 522 |
|
|
; d0,d1,d2,d3
|
| 523 |
|
|
;------------------------------------------------------------------------------
|
| 524 |
|
|
|
| 525 |
|
|
; // pad left
|
| 526 |
|
|
; if (width > 0) {
|
| 527 |
|
|
; if (ndx < width) {
|
| 528 |
|
|
; for (nn = 39; nn >= width-ndx; nn--)
|
| 529 |
|
|
; buf[nn] = buf[nn-(width-ndx)];
|
| 530 |
|
|
; for (; nn >= 0; nn--)
|
| 531 |
|
|
; buf[nn] = ' ';
|
| 532 |
|
|
; }
|
| 533 |
|
|
; }
|
| 534 |
|
|
|
| 535 |
|
|
_PadLeft:
|
| 536 |
|
|
movem.l d0/d1/d2/d3,-(a7)
|
| 537 |
|
|
tst.b _width
|
| 538 |
|
|
ble .0041
|
| 539 |
|
|
move.l a0,d0
|
| 540 |
|
|
sub.l #_fpBuf,d0 ; d0 = ndx
|
| 541 |
|
|
cmp.b _width,d0
|
| 542 |
|
|
bge .0041
|
| 543 |
|
|
move.w #49,d1 ; d1 = nn
|
| 544 |
|
|
.0040
|
| 545 |
|
|
move.b _width,d2
|
| 546 |
|
|
ext.w d2
|
| 547 |
|
|
sub.w d0,d2 ; d2 = width-ndx
|
| 548 |
|
|
cmp.w d2,d1
|
| 549 |
|
|
blt .0039
|
| 550 |
|
|
move.w d1,d3 ; d3 = nn
|
| 551 |
|
|
sub.w d2,d3 ; d3 = nn-(width-ndx)
|
| 552 |
|
|
move.b (a0,d3.w),(a0,d1.w)
|
| 553 |
|
|
subi.w #1,d1
|
| 554 |
|
|
bra .0040
|
| 555 |
|
|
.0039
|
| 556 |
|
|
tst.w d1
|
| 557 |
|
|
bmi .0041
|
| 558 |
|
|
move.b #' ',(a0,d1.w)
|
| 559 |
|
|
subi.w #1,d1
|
| 560 |
|
|
bra .0039
|
| 561 |
|
|
.0041
|
| 562 |
|
|
movem.l (a7)+,d0/d1/d2/d3
|
| 563 |
|
|
rts
|
| 564 |
|
|
|
| 565 |
|
|
;------------------------------------------------------------------------------
|
| 566 |
|
|
; Pad the right side of the output string.
|
| 567 |
|
|
;
|
| 568 |
|
|
; Parameters:
|
| 569 |
|
|
; a0 = pointer to end of string
|
| 570 |
|
|
; Modifies:
|
| 571 |
|
|
; none
|
| 572 |
|
|
; Returns:
|
| 573 |
|
|
; none
|
| 574 |
|
|
;------------------------------------------------------------------------------
|
| 575 |
|
|
|
| 576 |
|
|
; // pad right
|
| 577 |
|
|
; if (width < 0) {
|
| 578 |
|
|
; width = -width;
|
| 579 |
|
|
; while (ndx < width) {
|
| 580 |
|
|
; buf[ndx]=' ';
|
| 581 |
|
|
; ndx++;
|
| 582 |
|
|
; }
|
| 583 |
|
|
; buf[ndx]='\0';
|
| 584 |
|
|
; }
|
| 585 |
|
|
; return (ndx);
|
| 586 |
|
|
|
| 587 |
|
|
_PadRight:
|
| 588 |
|
|
move.l d0,-(a7)
|
| 589 |
|
|
tst.b _width
|
| 590 |
|
|
bpl .0042
|
| 591 |
|
|
neg.b _width
|
| 592 |
|
|
move.l a0,d0
|
| 593 |
|
|
sub.l #_fpBuf,d0 ; d0 = ndx
|
| 594 |
|
|
.0044
|
| 595 |
|
|
cmp.b _width,d0
|
| 596 |
|
|
bge .0043
|
| 597 |
|
|
move.b #' ',(a0,d0.w)
|
| 598 |
|
|
addi.w #1,d0
|
| 599 |
|
|
bra .0044
|
| 600 |
|
|
.0043
|
| 601 |
|
|
move.b #0,(a0,d0.w)
|
| 602 |
|
|
.0042
|
| 603 |
|
|
move.l (a7)+,d0
|
| 604 |
|
|
rts
|
| 605 |
|
|
|
| 606 |
|
|
;------------------------------------------------------------------------------
|
| 607 |
|
|
; Output a string representation of a decimal floating point number to a
|
| 608 |
|
|
; buffer.
|
| 609 |
|
|
;
|
| 610 |
|
|
; Register Usage
|
| 611 |
|
|
; a0 = pointer to string buffer
|
| 612 |
|
|
; d6 = exponent
|
| 613 |
|
|
; Modifies:
|
| 614 |
|
|
; a0 = points to end of string
|
| 615 |
|
|
; Parameters:
|
| 616 |
|
|
; fp0 = number to convert
|
| 617 |
|
|
; Returns:
|
| 618 |
|
|
; none
|
| 619 |
|
|
;------------------------------------------------------------------------------
|
| 620 |
|
|
|
| 621 |
|
|
_FloatToString:
|
| 622 |
|
|
move.l d6,-(a7)
|
| 623 |
|
|
bsr _CheckNegative ; is number negative?
|
| 624 |
|
|
bsr _CheckZero ; check for zero
|
| 625 |
|
|
beq .0001 ; branch since already output "0"
|
| 626 |
|
|
bsr _CheckNan ; check for Nan or infinity
|
| 627 |
|
|
bcs .0001 ; branch if nan/inf string output
|
| 628 |
|
|
; Now the fun begins
|
| 629 |
|
|
clr.l d6 ; exponent = 0
|
| 630 |
|
|
bsr _MakeBig
|
| 631 |
|
|
bsr _LessThanDbl
|
| 632 |
|
|
bsr _ComputeDigitsBeforeDecpt
|
| 633 |
|
|
bsr _LeadingZero
|
| 634 |
|
|
bsr _SpitOutDigits
|
| 635 |
|
|
bsr _TrimTrailingZeros
|
| 636 |
|
|
bsr _TrimTrailingPoint
|
| 637 |
|
|
bsr _TrimDotZero
|
| 638 |
|
|
bsr _ExtExpDigits ; extract exponent digits
|
| 639 |
|
|
bsr _PadLeft ; pad the number to the left or right
|
| 640 |
|
|
bsr _PadRight
|
| 641 |
|
|
.0001
|
| 642 |
|
|
move.l (a7)+,d6
|
| 643 |
|
|
rts
|
| 644 |
|
|
|
