-
Notifications
You must be signed in to change notification settings - Fork 12
/
instructions.c
61 lines (53 loc) · 1.58 KB
/
instructions.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
/* Copyright (c) 2014, Rob Thornton
* All rights reserved.
* This source code is governed by a Simplied BSD-License. Please see the
* LICENSE included in this distribution for a copy of the full license
* or, if one is not included, you may also find a copy at
* http://opensource.org/licenses/BSD-2-Clause */
#include "instructions.h"
#include "registers.h"
#include "stack.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* stack */
void enter(const int32_t n) {
if ((esp - &ss[0]) + 4 + n >= scap) {
fprintf(stderr, "Stack overflow!\n");
exit(EXIT_FAILURE);
}
*(int *)esp = ebp-&ss[0];
esp += 4;
ebp = esp;
esp += n;
}
void leave() {
esp = ebp;
esp -= 4;
ebp = &ss[0]+*(int *)esp;
}
void popl(char *dest) {
if ((esp - &ss[0]) - 4 < 0) {
fprintf(stderr, "Stack underflow!\n");
exit(EXIT_FAILURE);
}
esp -= 4;
movl(esp, dest);
}
void pushl(const char *src) {
if ((esp - &ss[0]) + 4 >= scap) {
fprintf(stderr, "Stack overflow!\n");
exit(EXIT_FAILURE);
}
movl(src, esp);
esp += 4;
}
/* memory */
void movl(const char *src, char *dest) { memmove(dest, src, sizeof (int32_t)); }
void setl(const int32_t n, char *dest) { movl((char *)&n, dest); }
/* arithmatic */
void addl(const char *src, char *dest) { *(int32_t *)dest += *(int32_t *)src; }
void divl(const char *src, char *dest) { *(int32_t *)dest /= *(int32_t *)src; }
void mull(const char *src, char *dest) { *(int32_t *)dest *= *(int32_t *)src; }
void reml(const char *src, char *dest) { *(int32_t *)dest %= *(int32_t *)src; }
void subl(const char *src, char *dest) { *(int32_t *)dest -= *(int32_t *)src; }