uxn-abc-disp.c (3643B)
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 #define next { ins = ram[pc++]; \ 27 m2 = ins & 0x20; \ 28 s = ins & 0x40 ? &u->rst : &u->wst; \ 29 if(ins & 0x80) kp = s->ptr, sp = &kp; else sp = &s->ptr; \ 30 goto *lut[ins & 0x1f]; } 31 32 int 33 uxn_eval(Uxn *u, Uint16 pc) 34 { 35 Uint8 t, kp, *sp, ins, m2, *ram = u->ram; 36 Uint16 tt, a, b, c; 37 Stack *s; 38 static void* lut[] = { 39 &&_imm, &&_inc, &&_pop, &&_nip, &&_swp, &&_rot, &&_dup, &&_ovr, 40 &&_equ, &&_neq, &&_gth, &&_lth, &&_jmp, &&_jcn, &&_jsr, &&_sth, 41 &&_ldz, &&_stz, &&_ldr, &&_str, &&_lda, &&_sta, &&_dei, &&_deo, 42 &&_add, &&_sub, &&_mul, &&_div, &&_and, &&_ora, &&_eor, &&_sft }; 43 if(!pc || u->dev[0x0f]) return 0; 44 next 45 _imm: 46 switch(ins) { 47 case 0x00: /* BRK */ return 1; 48 case 0x20: /* JCI */ POP1(b) if(!b) { pc += 2; break; } 49 case 0x40: /* JMI */ a = ram[pc++] << 8 | ram[pc++]; pc += a; break; 50 case 0x60: /* JSI */ PUSH2(pc + 2) a = ram[pc++] << 8 | ram[pc++]; pc += a; break; 51 case 0x80: case 0xc0: /* LIT */ PUSH1(ram[pc++]) break; 52 case 0xa0: case 0xe0: /* LIT2 */ PUSH1(ram[pc++]) PUSH1(ram[pc++]) break; 53 } next 54 _inc: POPx(a) PUSHx(a + 1) next 55 _pop: POPx(a) next 56 _nip: POPx(a) POPx(b) PUSHx(a) next 57 _swp: POPx(a) POPx(b) PUSHx(a) PUSHx(b) next 58 _rot: POPx(a) POPx(b) POPx(c) PUSHx(b) PUSHx(a) PUSHx(c) next 59 _dup: POPx(a) PUSHx(a) PUSHx(a) next 60 _ovr: POPx(a) POPx(b) PUSHx(b) PUSHx(a) PUSHx(b) next 61 _equ: POPx(a) POPx(b) PUSH1(b == a) next 62 _neq: POPx(a) POPx(b) PUSH1(b != a) next 63 _gth: POPx(a) POPx(b) PUSH1(b > a) next 64 _lth: POPx(a) POPx(b) PUSH1(b < a) next 65 _jmp: POPx(a) JUMP(a) next 66 _jcn: POPx(a) POP1(b) if(b) JUMP(a) next 67 _jsr: POPx(a) FLIP PUSH2(pc) JUMP(a) next 68 _sth: POPx(a) FLIP PUSHx(a) next 69 _ldz: POP1(a) PEEK(b, a, t) PUSHx(b) next 70 _stz: POP1(a) POPx(b) POKE(a, b, t) next 71 _ldr: POP1(a) PEEK(b, pc + (Sint8)a, tt) PUSHx(b) next 72 _str: POP1(a) POPx(b) POKE(pc + (Sint8)a, b, tt) next 73 _lda: POP2(a) PEEK(b, a, tt) PUSHx(b) next 74 _sta: POP2(a) POPx(b) POKE(a, b, tt) next 75 _dei: POP1(a) DEVR(b, a) PUSHx(b) next 76 _deo: POP1(a) POPx(b) DEVW(a, b) next 77 _add: POPx(a) POPx(b) PUSHx(b + a) next 78 _sub: POPx(a) POPx(b) PUSHx(b - a) next 79 _mul: POPx(a) POPx(b) PUSHx(b * a) next 80 _div: POPx(a) POPx(b) PUSHx(a ? b / a : 0) next 81 _and: POPx(a) POPx(b) PUSHx(b & a) next 82 _ora: POPx(a) POPx(b) PUSHx(b | a) next 83 _eor: POPx(a) POPx(b) PUSHx(b ^ a) next 84 _sft: POP1(a) POPx(b) PUSHx(b >> (a & 0xf) << (a >> 4)) next 85 }