#include #include "fakeasm.h" typedef unsigned char u8; u8 zero; //r16 u8 acc; //r17 u8 i0; //r18 u8 i1; //r19 u8 i2; //r20 u8 i3; //r21 u8 n; //r22 u8 s; //r23 u8 _; //r24 //r25 u8 x;/*==Ml*/ //r26 (Xlo) u8 t;/*==Mh*/ //r27 (Xhi) //r28 //r29 void *Z; //r30 (Zlo) /*...*/ //r31 (Zhi) #define Mh x //mod3 vars #define Ml t // -"- //http://homepage.divms.uiowa.edu/~jones/bcd/mod.shtml void mod3(void) { // mod3(Mh.Ml) -> t #define tmp _ ADD (Ml, Mh) CLR (Mh) ADC (Mh, zero, carry) //Mh only holds the carry bit MOV (tmp, Ml) SWAP (tmp) ANDI (tmp, 0x0f) SWAP (Mh) OR (tmp, Mh) ANDI (Ml, 0x0f) ADD (Ml, tmp) MOV (tmp, Ml) LSR (tmp) LSR (tmp) ANDI (Ml, 0x03) ADD (Ml, tmp) MOV (tmp, Ml) LSR (tmp) LSR (tmp) ANDI (Ml, 0x03) ADD (Ml, tmp) CPI (Ml, 3) BRPL (skip) SUBI (Ml, 3) skip:; RET #undef tmp } void g(void) { // g(i, t) -> t // tempvars: `x` and `_` static void* mul_jmptable[] = { // replaces data[] section at the top &&mul_84, &&mul_9d, &&mul_b0, &&mul_69, &&mul_9d, &&mul_84, &&mul_69, &&mul_58, &&mul_75, &&mul_8c, &&mul_b0, &&mul_69, &&mul_8c, &&mul_75, &&mul_69, &&mul_58 // addresses of mul_* stored in little endian (i.e. { lo(mul_84), hi(mul_84), ... }) }; #define tmp _ ANDI (t, 0x07) MOV (tmp, i2) ANDI (tmp, 3) TST (tmp) #undef tmp BREQ (skip) SUBI (t, -8) skip:; #define a1 x #define a2 _ #define a0 t CLR (a2) CLR (a1) goto *mul_jmptable[t]; /* LDI Xlo, lo(mul_jmptable) LDI Xhi, hi(mul_jmptable) ADD Xlo, t ADC Xhi, zero ADD Xlo, t ; advance twice, since it's a 16 bit address ADC Xhi, zero LD Zlo, X SUBI Xlo, -1 ADC Xhi, zero LD Zhi, X IJMP Z */ mul_58: // 0101 1000 (24cy) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) RJMP (endmul) mul_69: // 0110 1001 (26cy) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) RJMP (endmul) mul_75: // 0111 0101 (28cy) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) RJMP (endmul) mul_84: // 1000 0100 (22cy) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) RJMP (endmul) mul_8c: // 1000 1100 (24cy) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) RJMP (endmul) mul_9d: // 1001 1101 (28cy) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) RJMP (endmul) mul_b0: // 1011 0000 (22cy) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) LSR (a2) ROR (a1) LSR (a2) ROR (a1) ADD (a1, i0) ADC (a2, i1, carry) endmul: LSR (a2) //final shift is a common operation for all ROR (a1) // end MUL MOV (t, a1) #undef a0 #undef a1 #undef a2 RET //TODO: replace CALL/RET with IJMP? }; int main(void) { CLR (zero) CLR (i0) CLR (i1) CLR (i2) CLR (i3) for (;;) { MOV (n, i2) LSL (n) LSL (n) #define tmp _ MOV (tmp, i1) SWAP (tmp) ANDI (tmp, 0x0f) LSR (tmp) LSR (tmp) OR (n, tmp) #undef tmp MOV (s, i3) LSR (s) ROR (s) ANDI (s, 0x80) #define tmp _ MOV (tmp, i2) LSR (tmp) OR (s, tmp) #undef tmp //voice 1: MOV (t, n) RCALL g(); SWAP (t) ANDI (t, 1) MOV (acc, t) //voice 2: #define tmp _ MOV (tmp, i2) LSL (tmp) LSL (tmp) LSL (tmp) MOV (t, i1) SWAP (t) ANDI (t, 0xf) LSR (t) OR (t, tmp) #undef tmp EOR (t, n) RCALL g(); LSR (t) LSR (t) ANDI (t, 3) AND (t, s) ADD (acc, t) //voice 3: MOV (Ml, i2) SWAP (Ml) ANDI (Ml, 0xf0) LSL (Ml) #define tmp _ MOV (tmp, i1) LSR (tmp) LSR (tmp) LSR (tmp) OR (Ml, tmp) #undef tmp MOV (Mh, i3) SWAP (Mh) ANDI (Mh, 0xf0) LSL (Mh) #define tmp _ MOV (tmp, i2) LSR (tmp) LSR (tmp) LSR (tmp) OR (Mh, tmp) #undef tmp RCALL mod3(); ADD (t, n) RCALL g(); LSR (t) LSR (t) ANDI (t, 3) MOV (x, s) INC (x) #define tmp _ MOV (tmp, x) LSR (tmp) LSR (tmp) ADD (tmp, x) ROR (tmp) LSR (tmp) ADD (tmp, x) ROR (tmp) LSR (tmp) ADD (tmp, x) ROR (tmp) LSR (tmp) AND (t, tmp) #undef tmp ADD (acc, t) //voice 4: MOV (Ml, i2) SWAP (Ml) ANDI (Ml, 0xf0) LSL (Ml) LSL (Ml) #define tmp _ MOV (tmp, i1) LSR (tmp) LSR (tmp) OR (Ml, tmp) #undef tmp MOV (Mh, i3) SWAP (Mh) ANDI (Mh, 0xf0) LSL (Mh) LSL (Mh) #define tmp _ MOV (tmp, i2) LSR (tmp) LSR (tmp) OR (Mh, tmp) #undef tmp RCALL mod3(); SUB (t, n) NEG (t) SUBI (t, -8) RCALL g(); LSR (t) ANDI (t, 3) INC (s) #define tmp _ MOV (tmp, s) LSR (tmp) ADD (tmp, s) ROR (tmp) LSR (tmp) LSR (tmp) ADD (tmp, s) ROR (tmp) ADD (tmp, s) ROR (tmp) LSR (tmp) LSR (tmp) AND (t, tmp) #undef tmp ADD (acc, t) putchar(acc<<4); //TODO SUBI (i0, -1) ADC (i1, zero, !i0) ADC (i2, zero, !i0&&!i1) ADC (i3, zero, !i0&&!i1&&!i2) } }