foo.c

   1 #include <stdio.h>
   2 #include "fakeasm.h"
   3 typedef unsigned char u8;
   4
   5 u8 data[] = {
   6         0x84, 0x9d, 0xb0, 0x69, 0x9d, 0x84, 0x69, 0x58,
   7         0x75, 0x8c, 0xb0, 0x69, 0x8c, 0x75, 0x69, 0x58
   8 };
   9 u8 zero; //zero register
  10 u8 i0;
  11 u8 i1;
  12 u8 i2;
  13 u8 i3;
  14 u8 x;
  15 u8 t;
  16 u8 o;
  17 u8 _;
  18 void g(void) {
  19         // g(i, x, t, o) -> t
  20         #define tmp _
  21         ANDI    (t, 0x07)
  22         MOV     (tmp, i2)
  23         ANDI    (tmp, 3)
  24         TST     (tmp)
  25         #undef tmp
  26         BREQ    (skip)
  27         SUBI    (t, -8)
  28         skip:
  29         t = data[t];
  30         /*MOV X_hi==_, data_hi
  31           MOV X_lo==t, data_lo
  32           ADD X_lo, t
  33           ADC X_hi, zero
  34           LD  t, X         */
  35         t = (((i1&0x1f)<<8|i0)*t)>>8; //TODO
  36         t >>= o; //NOTE: o == {1, 2, 4}
  37         AND     (t, x)
  38         ANDI    (t, 3)
  39         RET
  40 };
  41
  42 int main(void) {
  43         u8 n;
  44         u8 s;
  45         u8 acc;
  46         //TODO: clear all vars/registers
  47         for (;;) {
  48                 MOV     (n, i2)
  49                 LSL     (n)
  50                 LSL     (n)
  51                 #define tmp acc
  52                 MOV     (tmp, i1)
  53                 SWAP    (tmp)
  54                 ANDI    (tmp, 0x0f)
  55                 LSR     (tmp)
  56                 LSR     (tmp)
  57                 OR      (n, tmp)
  58                 #undef tmp
  59                 MOV     (s, i3)
  60                 ROR     (s)
  61                 ROR     (s)
  62                 ANDI    (s, 0x80)
  63                 #define tmp acc
  64                 MOV     (tmp, i2)
  65                 LSR     (tmp)
  66                 OR      (s, tmp)
  67                 #undef tmp
  68
  69                 //voice 1:
  70                 LDI     (x, 1)
  71                 MOV     (t, n)
  72                 LDI     (o, 4)
  73                 RCALL   g();
  74                 MOV     (acc, t)
  75
  76                 //voice 2:
  77                 MOV     (x, s)
  78                 #define tmp o
  79                 MOV     (tmp, i2)
  80                 LSL     (tmp)
  81                 LSL     (tmp)
  82                 LSL     (tmp)
  83                 MOV     (t, i1)
  84                 SWAP    (t)
  85                 ANDI    (t, 0xf)
  86                 LSR     (t)
  87                 OR      (t, tmp)
  88                 #undef tmp
  89                 EOR     (t, n)
  90                 LDI     (o, 2)
  91                 RCALL   g();
  92                 ADD     (acc, t)
  93
  94                 //voice 3:
  95                 MOV     (x, s)
  96                 INC     (x)
  97                 #define tmp o
  98                 MOV     (tmp, x)
  99                 LSR     (tmp)
 100                 LSR     (tmp)
 101                 ADD     (tmp, x)
 102                 ROR     (tmp)
 103                 LSR     (tmp)
 104                 ADD     (tmp, x)
 105                 ROR     (tmp)
 106                 LSR     (tmp)
 107                 ADD     (tmp, x)
 108                 ROR     (tmp)
 109                 LSR     (tmp)
 110                 MOV     (x, tmp)
 111                 #undef tmp
 112                 t = ((i3&0x01)<<13 | i2<<5 | i1>>3) % 3; //TODO
 113                 ADD     (t, n)
 114                 LDI     (o, 2)
 115                 RCALL   g();
 116                 ADD     (acc, t)
 117
 118                 //voice 4:
 119                 MOV     (x, s)
 120                 INC     (x)
 121                 #define tmp o
 122                 MOV     (tmp, x)
 123                 LSR     (tmp)
 124                 ADD     (tmp, x)
 125                 ROR     (tmp)
 126                 LSR     (tmp)
 127                 LSR     (tmp)
 128                 ADD     (tmp, x)
 129                 ROR     (tmp)
 130                 ADD     (tmp, x)
 131                 ROR     (tmp)
 132                 LSR     (tmp)
 133                 LSR     (tmp)
 134                 MOV     (x, tmp)
 135                 #undef tmp
 136                 t = ((i3&0x01)<<14 | i2<<6 | i1>>2) % 3; //TODO
 137                 SUB     (t, n)
 138                 NEG     (t)
 139                 SUBI    (t, -8)
 140                 LDI     (o, 1)
 141                 RCALL   g();
 142                 ADD     (acc, t)
 143
 144                 putchar(acc<<4); //TODO
 145                 SUBI    (i0, -1)
 146                 ADC     (i1, zero, !i0)
 147                 ADC     (i2, zero, !i0&&!i1)
 148                 ADC     (i3, zero, !i0&&!i1&&!i2)
 149         }
 150 }