mirror of https://git.sr.ht/~rabbits/uxn
348 lines
9.0 KiB
C
348 lines
9.0 KiB
C
#include <stdio.h>
|
|
|
|
/*
|
|
Copyright (c) 2021 Devine Lu Linvega
|
|
|
|
Permission to use, copy, modify, and distribute this software for any
|
|
purpose with or without fee is hereby granted, provided that the above
|
|
copyright notice and this permission notice appear in all copies.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
WITH REGARD TO THIS SOFTWARE.
|
|
*/
|
|
|
|
typedef unsigned char Uint8;
|
|
typedef signed char Sint8;
|
|
typedef unsigned short Uint16;
|
|
typedef signed short Sint16;
|
|
|
|
typedef struct
|
|
{
|
|
char name[64];
|
|
unsigned int size;
|
|
} Map;
|
|
|
|
typedef struct {
|
|
char name[64];
|
|
Uint8 len, offset, refs;
|
|
Uint16 addr;
|
|
/* map */
|
|
Map map[16];
|
|
Uint8 maps;
|
|
} Label;
|
|
|
|
typedef struct {
|
|
Uint8 data[256 * 256], tlen, llen;
|
|
Uint16 ptr;
|
|
Label labels[256];
|
|
} Program;
|
|
|
|
Program p;
|
|
|
|
/* clang-format off */
|
|
|
|
char ops[][4] = {
|
|
"BRK", "NOP", "LIT", "JMP", "JSR", "RTS", "LDR", "STR",
|
|
"---", "---", "---", "---", "AND", "XOR", "ROL", "ROR",
|
|
"POP", "DUP", "SWP", "OVR", "ROT", "---", "WSR", "RSW",
|
|
"ADD", "SUB", "MUL", "DIV", "EQU", "NEQ", "GTH", "LTH"
|
|
};
|
|
|
|
int scin(char *s, char c) { int i = 0; while(s[i]) if(s[i++] == c) return i - 1; return -1; } /* string char index */
|
|
int scmp(char *a, char *b, int len) { int i = 0; while(a[i] == b[i] && i < len) if(!a[i++]) return 1; return 0; } /* string compare */
|
|
int slen(char *s) { int i = 0; while(s[i] && s[++i]) ; return i; } /* string length */
|
|
int sihx(char *s) { int i = 0; char c; while((c = s[i++])) if(!(c >= '0' && c <= '9') && !(c >= 'a' && c <= 'f') && !(c >= 'A' && c <= 'F')) return 0; return 1; } /* string is hexadecimal */
|
|
int shex(char *s) { int n = 0, i = 0; char c; while((c = s[i++])) if(c >= '0' && c <= '9') n = n * 16 + (c - '0'); else if(c >= 'A' && c <= 'F') n = n * 16 + 10 + (c - 'A'); else if(c >= 'a' && c <= 'f') n = n * 16 + 10 + (c - 'a'); return n; } /* string to num */
|
|
char *scpy(char *src, char *dst, int len) { int i = 0; while((dst[i] = src[i]) && i < len - 2) i++; dst[i + 1] = '\0'; return dst; } /* string copy */
|
|
|
|
#pragma mark - Helpers
|
|
|
|
/* clang-format on */
|
|
|
|
#pragma mark - I/O
|
|
|
|
void
|
|
pushbyte(Uint8 b, int lit)
|
|
{
|
|
if(lit) pushbyte(0x02, 0);
|
|
p.data[p.ptr++] = b;
|
|
}
|
|
|
|
void
|
|
pushshort(Uint16 s, int lit)
|
|
{
|
|
if(lit) pushbyte(0x22, 0);
|
|
pushbyte((s >> 8) & 0xff, 0);
|
|
pushbyte(s & 0xff, 0);
|
|
}
|
|
|
|
void
|
|
pushtext(char *s, int lit)
|
|
{
|
|
int i = 0;
|
|
char c;
|
|
if(lit) pushbyte(0x22, 0);
|
|
while((c = s[i++])) pushbyte(c, 0);
|
|
}
|
|
|
|
Label *
|
|
findlabel(char *s)
|
|
{
|
|
int i, rng = scin(s, '.');
|
|
char name[64];
|
|
scpy(s, name, rng > 0 ? rng + 1 : 64);
|
|
for(i = 0; i < p.llen; ++i)
|
|
if(scmp(p.labels[i].name, name, 64))
|
|
return &p.labels[i];
|
|
return NULL;
|
|
}
|
|
|
|
Uint16
|
|
findlabeladdr(char *s)
|
|
{
|
|
int i, o = 0;
|
|
char *param;
|
|
Label *l = findlabel(s);
|
|
if(scin(s, '.') < 1)
|
|
return l->addr;
|
|
param = s + scin(s, '.') + 1;
|
|
for(i = 0; i < l->maps; ++i) {
|
|
if(scmp(l->map[i].name, param, 64))
|
|
return l->addr + o;
|
|
o += l->map[i].size;
|
|
}
|
|
printf("!!! Warning %s.%s\n", l->name, param);
|
|
return 0;
|
|
}
|
|
|
|
Uint8
|
|
findlabellen(char *s)
|
|
{
|
|
int i;
|
|
char *param;
|
|
Label *l = findlabel(s);
|
|
if(scin(s, '.') < 1)
|
|
return l->len;
|
|
param = s + scin(s, '.') + 1;
|
|
for(i = 0; i < l->maps; ++i)
|
|
if(scmp(l->map[i].name, param, 64))
|
|
return l->map[i].size;
|
|
printf("!!! Warning %s.%s\n", l->name, param);
|
|
return 0;
|
|
}
|
|
|
|
Uint8
|
|
findopcode(char *s)
|
|
{
|
|
int i;
|
|
for(i = 0; i < 0x20; ++i) {
|
|
int m = 0;
|
|
char *o = ops[i];
|
|
if(o[0] != s[0] || o[1] != s[1] || o[2] != s[2])
|
|
continue;
|
|
while(s[3 + m]) {
|
|
if(s[3 + m] == '2') i |= (1 << 5); /* mode: short */
|
|
if(s[3 + m] == 'S') i |= (1 << 6); /* mode: signed */
|
|
if(s[3 + m] == '?') i |= (1 << 7); /* mode: conditional */
|
|
m++;
|
|
}
|
|
return i;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
char *
|
|
sublabel(char *src, char *scope, char *name)
|
|
{
|
|
scpy(scope, src, 64);
|
|
scpy("-", src + slen(src), 64);
|
|
scpy(name, src + slen(src), 64);
|
|
return src;
|
|
}
|
|
|
|
#pragma mark - Parser
|
|
|
|
int
|
|
error(char *name, char *id)
|
|
{
|
|
printf("Error: %s[%s]\n", name, id);
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
makelabel(char *name, Uint16 addr)
|
|
{
|
|
Label *l;
|
|
if(findlabel(name))
|
|
return error("Label duplicate", name);
|
|
if(sihx(name) && slen(name) % 2 == 0)
|
|
return error("Label name is hex number", name);
|
|
if(findopcode(name))
|
|
return error("Label name is invalid", name);
|
|
l = &p.labels[p.llen++];
|
|
l->addr = addr;
|
|
l->refs = 0;
|
|
scpy(name, l->name, 64);
|
|
printf("New label: %s, at 0x%04x[%d]\n", l->name, l->addr, l->len);
|
|
return 1;
|
|
}
|
|
|
|
int
|
|
makevariable(char *name, Uint16 *addr, FILE *f)
|
|
{
|
|
Label *l;
|
|
char word[64];
|
|
if(!makelabel(name, *addr))
|
|
return error("Could not create variable", name);
|
|
l = findlabel(name);
|
|
while(fscanf(f, "%s", word)) {
|
|
if(word[0] == '{') continue;
|
|
if(word[0] == '}') break;
|
|
scpy(word, l->map[l->maps].name, 64);
|
|
fscanf(f, "%u", &l->map[l->maps].size);
|
|
*addr += l->map[l->maps].size;
|
|
l->maps++;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int
|
|
skipblock(char *w, int *cap, char a, char b)
|
|
{
|
|
if(w[0] == b) {
|
|
*cap = 0;
|
|
return 1;
|
|
}
|
|
if(w[0] == a) *cap = 1;
|
|
if(*cap) return 1;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
pass1(FILE *f)
|
|
{
|
|
int ccmnt = 0, cbits = 0;
|
|
Uint16 addr = 0;
|
|
char w[64], scope[64], subw[64];
|
|
printf("Pass 1\n");
|
|
while(fscanf(f, "%s", w) == 1) {
|
|
if(skipblock(w, &ccmnt, '(', ')')) continue;
|
|
if(skipblock(w, &cbits, '[', ']')) {
|
|
if(w[0] == '[' || w[0] == ']')
|
|
continue;
|
|
if(sihx(w))
|
|
addr += slen(w) == 4 ? 2 : 1;
|
|
else
|
|
addr += slen(w);
|
|
} else if(w[0] == '@') {
|
|
if(!makelabel(w + 1, addr))
|
|
return error("Pass1 failed", w);
|
|
scpy(w + 1, scope, 64);
|
|
} else if(w[0] == '$') {
|
|
if(!makelabel(sublabel(subw, scope, w + 1), addr))
|
|
return error("Pass1 failed", w);
|
|
} else if(w[0] == ';') {
|
|
if(!makevariable(w + 1, &addr, f))
|
|
return error("Pass1 failed", w);
|
|
} else if(findopcode(w) || scmp(w, "BRK", 4))
|
|
addr += 1;
|
|
else {
|
|
switch(w[0]) {
|
|
case '|':
|
|
if(shex(w + 1) < addr)
|
|
return error("Memory Overlap", w);
|
|
addr = shex(w + 1);
|
|
break;
|
|
case '=': addr += 4; break; /* STR helper (lit addr-hb addr-lb str) */
|
|
case '~': addr += 4; break; /* LDR helper (lit addr-hb addr-lb ldr) */
|
|
case ',': addr += 3; break;
|
|
case '.': addr += 2; break;
|
|
case '^': addr += 2; break; /* Relative jump: lit addr-offset */
|
|
case '+': /* signed positive */
|
|
case '-': /* signed negative */
|
|
case '#': addr += (slen(w + 1) == 2 ? 2 : 3); break;
|
|
default: return error("Unknown label in first pass", w);
|
|
}
|
|
}
|
|
}
|
|
rewind(f);
|
|
return 1;
|
|
}
|
|
|
|
int
|
|
pass2(FILE *f)
|
|
{
|
|
int ccmnt = 0, cbits = 0, ctemplate = 0;
|
|
char w[64], scope[64], subw[64];
|
|
printf("Pass 2\n");
|
|
while(fscanf(f, "%s", w) == 1) {
|
|
Uint8 op = 0;
|
|
Label *l;
|
|
if(w[0] == ';') continue;
|
|
if(w[0] == '$') continue;
|
|
if(skipblock(w, &ccmnt, '(', ')')) continue;
|
|
if(skipblock(w, &ctemplate, '{', '}')) continue;
|
|
if(w[0] == '@') {
|
|
scpy(w + 1, scope, 64);
|
|
continue;
|
|
}
|
|
if(w[1] == '$') {
|
|
sublabel(subw, scope, w + 2);
|
|
scpy(subw, w + 1, 64);
|
|
}
|
|
/* clang-format off */
|
|
if(skipblock(w, &cbits, '[', ']')) {
|
|
if(w[0] == '[' || w[0] == ']') { continue; }
|
|
if(slen(w) == 4 && sihx(w)) pushshort(shex(w), 0);
|
|
else if(slen(w) == 2 && sihx(w)) pushbyte(shex(w), 0);
|
|
else pushtext(w, 0);
|
|
}
|
|
else if(w[0] == '^' && (l = findlabel(w + 1))) {
|
|
int off = l->addr - p.ptr - 3;
|
|
if(off < -126 || off > 126){ printf("Address %s is too far(%d).\n", w, off); return 0; }
|
|
pushbyte((Sint8)(l->addr - p.ptr - 3), 1); l->refs++;
|
|
}
|
|
else if(w[0] == '|') p.ptr = shex(w + 1);
|
|
else if((op = findopcode(w)) || scmp(w, "BRK", 4)) pushbyte(op, 0);
|
|
else if(w[0] == '.' && (l = findlabel(w + 1))) { pushshort(findlabeladdr(w + 1), 0); l->refs++; }
|
|
else if(w[0] == ',' && (l = findlabel(w + 1))) { pushshort(findlabeladdr(w + 1), 1); l->refs++; }
|
|
else if(w[0] == '=' && (l = findlabel(w + 1))) { pushshort(findlabeladdr(w + 1), 1); pushbyte(findopcode(findlabellen(w + 1) == 2 ? "STR2" : "STR"), 0); l->refs++;}
|
|
else if(w[0] == '~' && (l = findlabel(w + 1))) { pushshort(findlabeladdr(w + 1), 1); pushbyte(findopcode(findlabellen(w + 1) == 2 ? "LDR2" : "LDR"), 0); l->refs++;}
|
|
else if(w[0] == '#' && sihx(w + 1) && slen(w + 1) == 2) pushbyte(shex(w + 1), 1);
|
|
else if(w[0] == '#' && sihx(w + 1) && slen(w + 1) == 4) pushshort(shex(w + 1), 1);
|
|
else if(w[0] == '+' && sihx(w + 1) && slen(w + 1) == 2) pushbyte((Sint8)shex(w + 1), 1);
|
|
else if(w[0] == '+' && sihx(w + 1) && slen(w + 1) == 4) pushshort((Sint16)shex(w + 1), 1);
|
|
else if(w[0] == '-' && sihx(w + 1) && slen(w + 1) == 2) pushbyte((Sint8)(shex(w + 1) * -1), 1);
|
|
else if(w[0] == '-' && sihx(w + 1) && slen(w + 1) == 4) pushshort((Sint16)(shex(w + 1) * -1), 1);
|
|
else return error("Unknown label in second pass", w);
|
|
/* clang-format on */
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
cleanup(char *filename)
|
|
{
|
|
int i;
|
|
printf("Assembled %s.\n\n", filename);
|
|
for(i = 0; i < p.llen; ++i)
|
|
if(!p.labels[i].refs)
|
|
printf("--- Unused label: %s\n", p.labels[i].name);
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
FILE *f;
|
|
if(argc < 3)
|
|
return error("Input", "Missing");
|
|
if(!(f = fopen(argv[1], "r")))
|
|
return error("Open", "Failed");
|
|
if(!pass1(f) || !pass2(f))
|
|
return error("Assembly", "Failed");
|
|
fwrite(p.data, sizeof(p.data), 1, fopen(argv[2], "wb"));
|
|
fclose(f);
|
|
cleanup(argv[2]);
|
|
return 0;
|
|
}
|