73 lines
1.0 KiB
ArmAsm
73 lines
1.0 KiB
ArmAsm
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#include "libgcc.h"
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; numerator in A0/A1
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; denominator in A2/A3
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.global __modsi3
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__modsi3:
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PUSHP S2P
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bsr modnorm
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bsr __divsi3
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mov.l er3,er0
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bra exitdiv
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.global __umodsi3
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__umodsi3:
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bsr __udivsi3
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mov.l er3,er0
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rts
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.global __divsi3
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__divsi3:
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PUSHP S2P
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jsr divnorm
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bsr __udivsi3
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; examine what the sign should be
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exitdiv:
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btst #3,S2L
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beq reti
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; should be -ve
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neg.l A0P
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reti:
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POPP S2P
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rts
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divnorm:
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mov.l A0P,A0P ; is the numerator -ve
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stc ccr,S2L ; keep the sign in bit 3 of S2L
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bge postive
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neg.l A0P ; negate arg
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postive:
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mov.l A1P,A1P ; is the denominator -ve
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bge postive2
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neg.l A1P ; negate arg
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xor.b #0x08,S2L ; toggle the result sign
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postive2:
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rts
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;; Basically the same, except that the sign of the divisor determines
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;; the sign.
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modnorm:
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mov.l A0P,A0P ; is the numerator -ve
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stc ccr,S2L ; keep the sign in bit 3 of S2L
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bge mpostive
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neg.l A0P ; negate arg
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mpostive:
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mov.l A1P,A1P ; is the denominator -ve
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bge mpostive2
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neg.l A1P ; negate arg
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mpostive2:
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rts
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.end
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