95 lines
1.9 KiB
C
95 lines
1.9 KiB
C
// The OS/K Team licenses this file to you under the MIT license.
|
|
// See the LICENSE file in the project root for more information.
|
|
|
|
#include "arch.h"
|
|
|
|
void scan_param(ctx_t *ctx, acc_t *p)
|
|
{
|
|
ushort c;
|
|
reg_t *r;
|
|
|
|
assert(p != 0);
|
|
|
|
c = ctx->get(ctx);
|
|
|
|
if (c == A_MEM) {
|
|
p->mem = 1;
|
|
p->off = 0;
|
|
c = ctx->get(ctx);
|
|
}
|
|
|
|
else if (c == A_OFF) {
|
|
p->mem = 1;
|
|
p->off = (short)ctx->get(ctx);
|
|
c = ctx->get(ctx);
|
|
}
|
|
|
|
if (c >= A_IMM16) {
|
|
assert(p->type == A_REG);
|
|
p->type = c;
|
|
c = ctx->get(ctx);
|
|
}
|
|
|
|
p->val = c;
|
|
|
|
if (p->type == A_IMM32) {
|
|
p->val = (p->val << 16) | ctx->get(ctx);
|
|
}
|
|
|
|
else if (p->type == A_IMM64) {
|
|
p->val = (p->val << 16) | ctx->get(ctx);
|
|
p->val = (p->val << 16) | ctx->get(ctx);
|
|
p->val = (p->val << 16) | ctx->get(ctx);
|
|
}
|
|
|
|
else if (p->type == A_REG) {
|
|
if (p->val > NREGS) {
|
|
_except(ctx, E_ILL, "Inexistent REG");
|
|
}
|
|
|
|
r = &ctx->r[p->val];
|
|
|
|
if (r->flags & (RES | CTL)) {
|
|
_except(ctx, E_ACC, "Reserved REG");
|
|
}
|
|
}
|
|
}
|
|
|
|
void decode(ctx_t *ctx)
|
|
{
|
|
instr_t *i;
|
|
acc_t p1 = { 0 }, p2 = { 0 };
|
|
|
|
ulong rip = ctx->r[RIP].val;
|
|
ushort c = ctx->get(ctx);
|
|
|
|
if (c == 0xFFFF) {
|
|
log("0x%016lX: stop\n", rip);
|
|
_except(ctx, E_SHT, "Shutdown INSTR");
|
|
}
|
|
|
|
else if (ISPREF(c)) {
|
|
// nothing for now
|
|
}
|
|
|
|
else if (!ISINSTR(c)) {
|
|
_except(ctx, E_ILL, "Bad opcode 0x%4hX", c);
|
|
}
|
|
|
|
// Scanning an instruction
|
|
|
|
i = &ctx->i[c];
|
|
|
|
// Scan for parameters
|
|
if (i->prm1 != NOPRM) {
|
|
scan_param(ctx, &p1);
|
|
if (i->prm2 != NOPRM) {
|
|
scan_param(ctx, &p2);
|
|
}
|
|
}
|
|
|
|
dumpinstr(ctx, rip, c, &p1, &p2);
|
|
i->func(ctx, &p1, &p2);
|
|
}
|
|
|