mirror of https://git.sr.ht/~rabbits/uxn
217 lines
9.9 KiB
C
217 lines
9.9 KiB
C
#include <stdio.h>
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/*
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Copyright (u) 2021 Devine Lu Linvega
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Permission to use, copy, modify, and distribute this software for any
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purpose with or without fee is hereby granted, provided that the above
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copyright notice and this permission notice appear in all copies.
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THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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WITH REGARD TO THIS SOFTWARE.
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*/
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#include "uxn.h"
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#pragma mark - Operations
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/* clang-format off */
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void setflag(Uint8 *a, char flag, int b) { if(b) *a |= flag; else *a &= (~flag); }
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int getflag(Uint8 *a, char flag) { return *a & flag; }
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Uint8 devpoke8(Uxn *u, Uint8 id, Uint8 b0, Uint8 b1){ return id < u->devices ? u->dev[id].poke(u->ram.dat, 0xff00 + id * 0x10, b0, b1) : b1; }
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void mempoke8(Uxn *u, Uint16 a, Uint8 b) { u->ram.dat[a] = a >= 0xff00 ? devpoke8(u, (a & 0xff) >> 4, a & 0xf, b) : b; }
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Uint8 mempeek8(Uxn *u, Uint16 a) { return u->ram.dat[a]; }
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void mempoke16(Uxn *u, Uint16 a, Uint16 b) { mempoke8(u, a, b >> 8); mempoke8(u, a + 1, b); }
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Uint16 mempeek16(Uxn *u, Uint16 a) { return (mempeek8(u, a) << 8) + mempeek8(u, a + 1); }
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void push8(Stack *s, Uint8 a) { s->dat[s->ptr++] = a; }
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Uint8 pop8(Stack *s) { return s->dat[--s->ptr]; }
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Uint8 peek8(Stack *s, Uint8 a) { return s->dat[s->ptr - a - 1]; }
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void push16(Stack *s, Uint16 a) { push8(s, a >> 8); push8(s, a); }
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Uint16 pop16(Stack *s) { return pop8(s) + (pop8(s) << 8); }
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Uint16 peek16(Stack *s, Uint8 a) { return peek8(s, a * 2) + (peek8(s, a * 2 + 1) << 8); }
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/* I/O */
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void op_brk(Uxn *u) { setflag(&u->status, FLAG_HALT, 1); }
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void op_lit(Uxn *u) { u->literal += 1; }
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void op_nop(Uxn *u) { (void)u; }
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void op_jmp(Uxn *u) { Uint8 a = pop8(&u->wst); u->ram.ptr += getflag(&u->status, FLAG_SIGN) ? (Sint8)a : a; }
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void op_jsr(Uxn *u) { Uint8 a = pop8(&u->wst); push16(&u->rst, u->ram.ptr); u->ram.ptr += getflag(&u->status, FLAG_SIGN) ? (Sint8)a : a; }
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void op_rts(Uxn *u) { u->ram.ptr = pop16(&u->rst); }
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void op_ldr(Uxn *u) { Uint16 a = pop16(&u->wst); push8(&u->wst, mempeek8(u, a)); }
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void op_str(Uxn *u) { Uint16 a = pop16(&u->wst); Uint8 b = pop8(&u->wst); mempoke8(u, a, b); }
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/* Logic */
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void op_and(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b & a); }
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void op_xor(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b | a); }
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void op_rol(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b << (a % 8)); }
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void op_ror(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b >> (a % 8)); }
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/* Stack */
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void op_pop(Uxn *u) { pop8(&u->wst); }
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void op_dup(Uxn *u) { push8(&u->wst, peek8(&u->wst, 0)); }
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void op_swp(Uxn *u) { Uint8 b = pop8(&u->wst), a = pop8(&u->wst); push8(&u->wst, b); push8(&u->wst, a); }
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void op_ovr(Uxn *u) { push8(&u->wst, peek8(&u->wst, 1)); }
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void op_rot(Uxn *u) { Uint8 c = pop8(&u->wst), b = pop8(&u->wst), a = pop8(&u->wst); push8(&u->wst, b); push8(&u->wst, c); push8(&u->wst, a); }
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void op_wsr(Uxn *u) { Uint8 a = pop8(&u->wst); push8(&u->rst, a); }
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void op_rsw(Uxn *u) { Uint8 a = pop8(&u->rst); push8(&u->wst, a); }
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/* Arithmetic */
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void op_add(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b + (Sint8)a : b + a); }
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void op_sub(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b - (Sint8)a : b - a); }
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void op_mul(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b * (Sint8)a : b * a); }
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void op_div(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b / (Sint8)a : b / a); }
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void op_equ(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b == (Sint8)a : b == a); }
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void op_neq(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b != (Sint8)a : b != a); }
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void op_gth(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b > (Sint8)a : b > a); }
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void op_lth(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint8)b < (Sint8)a : b < a); }
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/* --- */
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void op_lit16(Uxn *u) { u->literal += 2; }
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void op_nop16(Uxn *u) { printf("%04x\n", pop16(&u->wst)); }
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void op_jmp16(Uxn *u) { u->ram.ptr = pop16(&u->wst); }
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void op_jsr16(Uxn *u) { push16(&u->rst, u->ram.ptr); u->ram.ptr = pop16(&u->wst); }
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void op_ldr16(Uxn *u) { Uint16 a = pop16(&u->wst); push16(&u->wst, mempeek16(u, a)); }
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void op_str16(Uxn *u) { Uint16 a = pop16(&u->wst); Uint16 b = pop16(&u->wst); mempoke16(u, a, b); }
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void op_and16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b & a); }
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void op_xor16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b ^ a); }
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void op_rol16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b << (a % 16)); }
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void op_ror16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b >> (a % 16)); }
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/* Stack(16-bits) */
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void op_pop16(Uxn *u) { pop16(&u->wst); }
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void op_dup16(Uxn *u) { push16(&u->wst, peek16(&u->wst, 0)); }
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void op_swp16(Uxn *u) { Uint16 b = pop16(&u->wst), a = pop16(&u->wst); push16(&u->wst, b); push16(&u->wst, a); }
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void op_ovr16(Uxn *u) { push16(&u->wst, peek16(&u->wst, 1)); }
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void op_rot16(Uxn *u) { Uint16 c = pop16(&u->wst), b = pop16(&u->wst), a = pop16(&u->wst); push16(&u->wst, b); push16(&u->wst, c); push16(&u->wst, a); }
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void op_wsr16(Uxn *u) { Uint16 a = pop16(&u->wst); push16(&u->rst, a); }
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void op_rsw16(Uxn *u) { Uint16 a = pop16(&u->rst); push16(&u->wst, a); }
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/* Arithmetic(16-bits) */
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void op_add16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b + (Sint16)a : b + a); }
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void op_sub16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b - (Sint16)a : b - a); }
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void op_mul16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b * (Sint16)a : b * a); }
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void op_div16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b / (Sint16)a : b / a); }
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void op_equ16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b == (Sint16)a : b == a); }
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void op_neq16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b != (Sint16)a : b != a); }
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void op_gth16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b > (Sint16)a : b > a); }
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void op_lth16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push8(&u->wst, getflag(&u->status, FLAG_SIGN) ? (Sint16)b < (Sint16)a : b < a); }
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void (*ops[])(Uxn *u) = {
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op_brk, op_nop, op_lit, op_jmp, op_jsr, op_rts, op_ldr, op_str,
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op_nop, op_nop, op_nop, op_nop, op_and, op_xor, op_rol, op_ror,
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op_pop, op_dup, op_swp, op_ovr, op_rot, op_nop, op_wsr, op_rsw,
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op_add, op_sub, op_mul, op_div, op_equ, op_neq, op_gth, op_lth,
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/* 16-bit */
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op_brk, op_nop16, op_lit16, op_jmp16, op_jsr16, op_rts, op_ldr16, op_str16,
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op_nop, op_nop, op_nop, op_nop, op_and16, op_xor16, op_rol16, op_ror16,
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op_pop16, op_dup16, op_swp16, op_ovr16, op_rot16, op_wsr16, op_rsw16, op_nop,
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op_add16, op_sub16, op_mul16, op_div16, op_equ16, op_neq16, op_gth16, op_lth16
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};
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Uint8 opr[][2] = {
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{0,0}, {0,0}, {0,0}, {1,0}, {1,0}, {0,0}, {2,1}, {3,0},
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{2,0}, {2,0}, {0,0}, {0,0}, {2,1}, {2,1}, {2,1}, {2,1},
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{1,0}, {1,2}, {2,2}, {2,3}, {3,3}, {1,0}, {0,1}, {2,1},
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{2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1},
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/* 16-bit */
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{0,0}, {0,0}, {0,0}, {2,0}, {2,0}, {0,0}, {2,2}, {4,0}, /* TODO */
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{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, /* TODO */
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{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {2,0}, {0,2}, {0,0}, /* TODO */
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{4,2}, {4,2}, {4,2}, {4,2}, {4,2}, {4,2}, {4,2}, {4,2}
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};
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/* clang-format on */
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#pragma mark - Core
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int
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haltuxn(Uxn *u, char *name, int id)
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{
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printf("Halted: %s#%04x, at 0x%04x\n", name, id, u->counter);
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op_nop(u);
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return 0;
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}
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int
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lituxn(Uxn *u, Uint8 instr)
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{
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if(u->wst.ptr >= 255)
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return haltuxn(u, "Stack overflow", instr);
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push8(&u->wst, instr);
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u->literal--;
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return 1;
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}
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int
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opcuxn(Uxn *u, Uint8 instr)
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{
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Uint8 op = instr & 0x1f;
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setflag(&u->status, FLAG_SHORT, (instr >> 5) & 1);
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setflag(&u->status, FLAG_SIGN, (instr >> 6) & 1);
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setflag(&u->status, FLAG_COND, (instr >> 7) & 1);
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if(getflag(&u->status, FLAG_SHORT))
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op += 32;
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if(u->wst.ptr < opr[op][0])
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return haltuxn(u, "Stack underflow", op);
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if(u->wst.ptr + opr[op][1] - opr[op][0] >= 255)
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return haltuxn(u, "Stack overflow", instr);
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if(!getflag(&u->status, FLAG_COND) || (getflag(&u->status, FLAG_COND) && pop8(&u->wst)))
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(*ops[op])(u);
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return 1;
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}
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int
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stepuxn(Uxn *u, Uint8 instr)
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{
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if(u->literal > 0)
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return lituxn(u, instr);
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else
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return opcuxn(u, instr);
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}
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int
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evaluxn(Uxn *u, Uint16 vec)
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{
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u->literal = 0;
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u->ram.ptr = vec;
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setflag(&u->status, FLAG_HALT, 0);
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while(!(u->status & FLAG_HALT)) {
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Uint8 instr = u->ram.dat[u->ram.ptr++];
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if(!stepuxn(u, instr))
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return 0;
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u->counter++;
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}
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return 1;
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}
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int
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bootuxn(Uxn *u)
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{
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size_t i;
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char *cptr = (char *)&u;
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for(i = 0; i < sizeof u; i++)
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cptr[i] = 0;
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return 1;
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}
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int
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loaduxn(Uxn *u, char *filepath)
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{
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FILE *f;
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if(!(f = fopen(filepath, "rb")))
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return haltuxn(u, "Missing input rom.", 0);
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fread(u->ram.dat, sizeof(u->ram.dat), 1, f);
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u->vreset = mempeek16(u, 0xfff0);
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u->vframe = mempeek16(u, 0xfff2);
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u->verror = mempeek16(u, 0xfff4);
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printf("Uxn loaded[%s] vrst:%04x vfrm:%04x verr:%04x.\n",
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filepath,
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u->vreset,
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u->vframe,
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u->verror);
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return 1;
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}
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Device *
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portuxn(Uxn *u, char *name, Uint8 (*pofn)(Uint8 *m, Uint16 ptr, Uint8 b0, Uint8 b1))
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{
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Device *d = &u->dev[u->devices++];
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d->addr = 0xff00 + (u->devices - 1) * 0x10;
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d->poke = pofn;
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printf("Device #%d: %s, at 0x%04x \n", u->devices - 1, name, d->addr);
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return d;
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}
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