d6
/
uxn
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

(uxn.c) Aligned BRK/JCI/JMI

This commit is contained in:
Devine Lu Linvega 2023-07-23 09:52:20 -07:00
parent bc4ec9ea5f
commit db6f7d9fbf
1 changed files with 6 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/uxn.c
View File

@ -39,19 +39,19 @@ WITH REGARD TO THIS SOFTWARE.
int int
uxn_eval(Uxn *u, Uint16 pc) uxn_eval(Uxn *u, Uint16 pc)
{ {
int t, n, l, k, tmp, opc, ins; int t, n, l, k, tmp, ins;
Uint8 *ram = u->ram; Uint8 *ram = u->ram, opc;
Stack *s; Stack *s;
if(!pc || u->dev[0x0f]) return 0; if(!pc || u->dev[0x0f]) return 0;
for(;;) { for(;;) {
ins = ram[pc++]; ins = ram[pc++];
k = ins & 0x80 ? 0xff : 0; k = ins & 0x80 ? 0xff : 0;
s = ins & 0x40 ? &u->rst : &u->wst; s = ins & 0x40 ? &u->rst : &u->wst;
opc = !(ins & 0x1f) ? (0 - (ins >> 5)) & 0xff : ins & 0x3f; opc = !(ins & 0x1f) ? (0 - (ins >> 5)) : ins & 0x3f;
switch(opc) { switch(opc) {
/* IMM */ /* IMM */
case 0x00: /* BRK */ return 1; case 0x00: /* BRK */ return 1;
case 0xff: /* JCI */ pc += !!s->dat[--s->ptr] * PEEK2(ram + pc) + 2; break; case 0xff: /* JCI */ if(!s->dat[--s->ptr]) { pc += 2; break; }
case 0xfe: /* JMI */ pc += PEEK2(ram + pc) + 2; break; case 0xfe: /* JMI */ pc += PEEK2(ram + pc) + 2; break;
case 0xfd: /* JSI */ SET(0, 2) PUT2(0, pc + 2) pc += PEEK2(ram + pc) + 2; break; case 0xfd: /* JSI */ SET(0, 2) PUT2(0, pc + 2) pc += PEEK2(ram + pc) + 2; break;
case 0xfc: /* LIT */ SET(0, 1) PUT(0, ram[pc++]) break; case 0xfc: /* LIT */ SET(0, 1) PUT(0, ram[pc++]) break;