uxn-abc.c (3933B)
1 #include "uxn.h" 2 3 /* 4 Copyright (u) 2022-2023 Devine Lu Linvega, Andrew Alderwick, Andrew Richards 5 6 Permission to use, copy, modify, and distribute this software for any 7 purpose with or without fee is hereby granted, provided that the above 8 copyright notice and this permission notice appear in all copies. 9 10 THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 WITH REGARD TO THIS SOFTWARE. 12 */ 13 14 #define FLIP { s = ins & 0x40 ? &u->wst : &u->rst; } 15 #define JUMP(x) { if(m2) pc = (x); else pc += (Sint8)(x); } 16 #define POP1(o) { o = s->dat[--*sp]; } 17 #define POP2(o) { o = s->dat[--*sp] | (s->dat[--*sp] << 0x8); } 18 #define POPx(o) { if(m2) { POP2(o) } else POP1(o) } 19 #define PUSH1(y) { s->dat[s->ptr++] = (y); } 20 #define PUSH2(y) { tt = (y); s->dat[s->ptr++] = tt >> 0x8; s->dat[s->ptr++] = tt; } 21 #define PUSHx(y) { if(m2) { PUSH2(y) } else PUSH1(y) } 22 #define PEEK(o, x, r) { if(m2) { r = (x); o = ram[r++] << 8 | ram[r]; } else o = ram[(x)]; } 23 #define POKE(x, y, r) { if(m2) { r = (x); ram[r++] = y >> 8; ram[r] = y; } else ram[(x)] = (y); } 24 #define DEVR(o, p) { if(m2) { o = (emu_dei(u, p) << 8) | emu_dei(u, p + 1); } else o = emu_dei(u, p); } 25 #define DEVW(p, y) { if(m2) { emu_deo(u, p, y >> 8); emu_deo(u, p + 1, y); } else emu_deo(u, p, y); } 26 27 int 28 uxn_eval(Uxn *u, Uint16 pc) 29 { 30 Uint8 t, kp, *sp, *ram = u->ram; 31 Uint16 tt, a, b, c; 32 if(!pc || u->dev[0x0f]) return 0; 33 for(;;) { 34 Uint8 ins = ram[pc++]; 35 /* 2 */ Uint8 m2 = ins & 0x20; 36 /* r */ Stack *s = ins & 0x40 ? &u->rst : &u->wst; 37 /* k */ if(ins & 0x80) kp = s->ptr, sp = &kp; else sp = &s->ptr; 38 switch(ins & 0x1f) { 39 case 0x00: 40 switch(ins) { 41 case 0x00: /* BRK */ return 1; 42 case 0x20: /* JCI */ POP1(b) if(!b) { pc += 2; break; } 43 case 0x40: /* JMI */ a = ram[pc++] << 8 | ram[pc++]; pc += a; break; 44 case 0x60: /* JSI */ PUSH2(pc + 2) a = ram[pc++] << 8 | ram[pc++]; pc += a; break; 45 case 0x80: case 0xc0: /* LIT */ PUSH1(ram[pc++]) break; 46 case 0xa0: case 0xe0: /* LIT2 */ PUSH1(ram[pc++]) PUSH1(ram[pc++]) break; 47 } break; 48 case 0x01: /* INC */ POPx(a) PUSHx(a + 1) break; 49 case 0x02: /* POP */ POPx(a) break; 50 case 0x03: /* NIP */ POPx(a) POPx(b) PUSHx(a) break; 51 case 0x04: /* SWP */ POPx(a) POPx(b) PUSHx(a) PUSHx(b) break; 52 case 0x05: /* ROT */ POPx(a) POPx(b) POPx(c) PUSHx(b) PUSHx(a) PUSHx(c) break; 53 case 0x06: /* DUP */ POPx(a) PUSHx(a) PUSHx(a) break; 54 case 0x07: /* OVR */ POPx(a) POPx(b) PUSHx(b) PUSHx(a) PUSHx(b) break; 55 case 0x08: /* EQU */ POPx(a) POPx(b) PUSH1(b == a) break; 56 case 0x09: /* NEQ */ POPx(a) POPx(b) PUSH1(b != a) break; 57 case 0x0a: /* GTH */ POPx(a) POPx(b) PUSH1(b > a) break; 58 case 0x0b: /* LTH */ POPx(a) POPx(b) PUSH1(b < a) break; 59 case 0x0c: /* JMP */ POPx(a) JUMP(a) break; 60 case 0x0d: /* JCN */ POPx(a) POP1(b) if(b) JUMP(a) break; 61 case 0x0e: /* JSR */ POPx(a) FLIP PUSH2(pc) JUMP(a) break; 62 case 0x0f: /* STH */ POPx(a) FLIP PUSHx(a) break; 63 case 0x10: /* LDZ */ POP1(a) PEEK(b, a, t) PUSHx(b) break; 64 case 0x11: /* STZ */ POP1(a) POPx(b) POKE(a, b, t) break; 65 case 0x12: /* LDR */ POP1(a) PEEK(b, pc + (Sint8)a, tt) PUSHx(b) break; 66 case 0x13: /* STR */ POP1(a) POPx(b) POKE(pc + (Sint8)a, b, tt) break; 67 case 0x14: /* LDA */ POP2(a) PEEK(b, a, tt) PUSHx(b) break; 68 case 0x15: /* STA */ POP2(a) POPx(b) POKE(a, b, tt) break; 69 case 0x16: /* DEI */ POP1(a) DEVR(b, a) PUSHx(b) break; 70 case 0x17: /* DEO */ POP1(a) POPx(b) DEVW(a, b) break; 71 case 0x18: /* ADD */ POPx(a) POPx(b) PUSHx(b + a) break; 72 case 0x19: /* SUB */ POPx(a) POPx(b) PUSHx(b - a) break; 73 case 0x1a: /* MUL */ POPx(a) POPx(b) PUSHx(b * a) break; 74 case 0x1b: /* DIV */ POPx(a) POPx(b) PUSHx(a ? b / a : 0) break; 75 case 0x1c: /* AND */ POPx(a) POPx(b) PUSHx(b & a) break; 76 case 0x1d: /* ORA */ POPx(a) POPx(b) PUSHx(b | a) break; 77 case 0x1e: /* EOR */ POPx(a) POPx(b) PUSHx(b ^ a) break; 78 case 0x1f: /* SFT */ POP1(a) POPx(b) PUSHx(b >> (a & 0xf) << (a >> 4)) break; 79 } 80 } 81 }