commit 5f7046b6897415957c6759c755d470ff138bd494
Author: Brian Swetland <swetland@frotz.net>
Date: Wed, 4 Apr 2012 03:33:47 -0700
It compiles but is otherwise untested.
Diffstat:
| A | dcpu.c | | | 143 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 143 insertions(+), 0 deletions(-)
diff --git a/dcpu.c b/dcpu.c
@@ -0,0 +1,143 @@
+/* Copyright 2012, Brian Swetland. BSD Licensed. Share and Enjoy! */
+/* A DCPU-16 Implementation */
+
+/* DCPU-16 Spec is Copyright 2012 Mojang */
+/* http://0x10c.com/doc/dcpu-16.txt */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+typedef uint16_t u16;
+typedef uint32_t u32;
+
+struct dcpu {
+ u16 r[8];
+ u16 pc;
+ u16 sp;
+ u16 ov;
+ u16 skip;
+ u16 m[65536];
+};
+
+static u16 lit[0x20] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+};
+
+u16 *dcpu_opr(struct dcpu *d, u16 code) {
+ switch (code) {
+ case 0x00: case 0x01: case 0x02: case 0x03:
+ case 0x04: case 0x05: case 0x06: case 0x07:
+ return d->r + code;
+ case 0x08: case 0x09: case 0x0a: case 0x0b:
+ case 0x0c: case 0x0d: case 0x0e: case 0x0f:
+ return d->m + d->r[code & 7];
+ case 0x10: case 0x11: case 0x12: case 0x13:
+ case 0x14: case 0x15: case 0x16: case 0x17:
+ return d->m + ((d->r[code & 7] + d->m[d->pc++]) & 0xffff);
+ case 0x18:
+ return d->m + d->sp++;
+ case 0x19:
+ return d->m + d->sp;
+ case 0x1a:
+ return d->m + (--(d->sp));
+ case 0x1b:
+ return &d->sp;
+ case 0x1c:
+ return &d->pc;
+ case 0x1d:
+ return &d->ov;
+ case 0x1e:
+ return d->m + d->m[d->pc++];
+ case 0x1f:
+ return d->m + d->pc++;
+ default:
+ return lit + (code & 0x1F);
+ }
+}
+
+void dcpu_step(struct dcpu *d) {
+ u16 op = d->m[d->pc++];
+ u16 dst;
+ u32 res;
+ u16 a, b, *aa;
+
+ if ((op & 0xF) == 0) {
+ switch ((op >> 4) & 0x3F) {
+ case 0x01:
+ a = *dcpu_opr(d, op >> 10);
+ if (d->skip) {
+ d->skip = 0;
+ } else {
+ d->m[--(d->sp)] = d->pc;
+ d->pc = a;
+ }
+ return;
+ default:
+ return;
+ }
+ }
+
+ aa = dcpu_opr(d, dst = (op >> 4) & 0x3F);
+ a = *aa;
+ b = *dcpu_opr(d, op >> 10);
+
+ switch (op & 0xF) {
+ case 0x1: res = b;
+ break;
+ case 0x2: res = a + b;
+ break;
+ case 0x3: res = a - b;
+ break;
+ case 0x4: res = a * b;
+ break;
+ case 0x5: if (b) { res = a / b; } else { res = 0; }
+ break;
+ case 0x6: if (b) { res = a % b; } else { res = 0; }
+ break;
+ case 0x7: res = a << b;
+ break;
+ case 0x8: res = a >> b;
+ break;
+ case 0x9: res = a & b;
+ break;
+ case 0xA: res = a | b;
+ break;
+ case 0xB: res = a ^ b;
+ break;
+ case 0xC: res = (a==b);
+ goto cond;
+ case 0xD: res = (a!=b);
+ goto cond;
+ case 0xE: res = (a>b);
+ goto cond;
+ case 0xF: res = ((a&b)!=0);
+ goto cond;
+ }
+
+ if (d->skip) {
+ d->skip = 0;
+ return;
+ }
+ if (dst < 0x1f) {
+ *aa = res;
+ d->ov = res >> 16;
+ }
+ return;
+
+cond:
+ if (d->skip) {
+ d->skip = 0;
+ return;
+ }
+ d->skip = res;
+}
+
+int main(int argc, char **argv) {
+ struct dcpu d;
+ return 0;
+}
+
