retroforth/tools/retro-muri.c
crc 52536767d1 retro-muri: cleanups, separate each step into a separate pass
FossilOrigin-Name: 0b883a21d86730a59b1886555d42a2753fad06f5c48bd12e0a372aa20a03168a
2020-10-16 14:28:14 +00:00

334 lines
8.6 KiB
C

/* retro-muri.c
Copyright (c) 2017-2020 Charles Childers
Copyright (c) 2019 Luke Parrish
This is the standard assembler for Nga. It's primarily used
to build the RETRO kernel (rx.muri).
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <sys/types.h>
#ifndef BIT64
#define CELL int32_t
#define CELL_MIN INT_MIN + 1
#define CELL_MAX INT_MAX - 1
#else
#define CELL int64_t
#define CELL_MIN LLONG_MIN + 1
#define CELL_MAX LLONG_MAX - 1
#endif
#define KiB * 1024
#define MAX_NAMES 1024
#define STRING_LEN 64
#ifndef IMAGE_SIZE
#define IMAGE_SIZE 128 KiB
#endif
char Labels[MAX_NAMES][STRING_LEN];
CELL Pointers[MAX_NAMES];
CELL np;
char source[1 KiB];
CELL target[IMAGE_SIZE];
CELL here;
typedef void (*Handler)(char *);
void unu(char *, int, Handler);
size_t bsd_strlcat(char *dst, const char *src, size_t dsize);
size_t bsd_strlcpy(char *dst, const char *src, size_t dsize);
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
/* *********************************************************************** */
/* retro-unu is used to extract code blocks from a source file.
I embed a minimal version of this here. */
char code_start[33], code_end[33], test_start[33], test_end[33];
typedef void (*Handler)(char *);
void read_line(FILE *file, char *line_buffer) {
int ch = getc(file);
int count = 0;
while ((ch != '\n') && (ch != EOF)) {
line_buffer[count] = ch;
count++;
ch = getc(file);
}
line_buffer[count] = '\0';
}
int fence_boundary(char *buffer, int tests_enabled) {
int flag = 1;
if (strcmp(buffer, code_start) == 0) { flag = -1; }
if (strcmp(buffer, code_end) == 0) { flag = -1; }
if (tests_enabled == 0) { return flag; }
if (strcmp(buffer, test_start) == 0) { flag = -1; }
if (strcmp(buffer, test_end) == 0) { flag = -1; }
return flag;
}
void unu(char *fname, int tests_enabled, Handler handler) {
int inBlock = 0;
char buffer[4096];
FILE *fp;
fp = fopen(fname, "r");
if (fp == NULL) {
printf("Unable to load file\n");
exit(2);
}
while (!feof(fp)) {
read_line(fp, buffer);
if (fence_boundary(buffer, tests_enabled) == -1) {
if (inBlock == 0) {
inBlock = 1;
} else {
inBlock = 0;
}
} else {
if (inBlock == 1) {
handler(buffer);
}
}
}
fclose(fp);
}
/* *********************************************************************** */
/* save() writes the assembled image to a file named `ngaImage`. */
void save() {
FILE *fp;
if ((fp = fopen("ngaImage", "wb")) == NULL) {
printf("Unable to save the image!\n");
exit(2);
}
fwrite(&target, sizeof(CELL), here, fp);
fclose(fp);
}
/* lookup() finds a label name and returs its offset in the image */
CELL lookup(char *name) {
CELL slice = -1;
CELL n = np;
while (n > 0) {
n--;
if (strcmp(Labels[n], name) == 0)
slice = Pointers[n];
}
return slice;
}
/* add_label() stores a name and location for later use by lookup() */
void add_label(char *name, CELL slice) {
if (lookup(name) == -1) {
bsd_strlcpy(Labels[np], name, STRING_LEN);
Pointers[np] = slice;
np++;
} else {
printf("Fatal error: %s already defined\n", name);
exit(0);
}
}
/* opcode_for() returns the opcode value for a two letter instruction name. */
CELL opcode_for(char *s) {
char* opcodeList = "..lidudrswpupojucaccreeqneltgtfestadsumudianorxoshzrhaieiqii";
int16_t* s16 = (int16_t *)s;
int16_t* op16 = (int16_t *)opcodeList;
int i = 0;
for(i = 0; i <= 30; i++){
if(s16[0] == op16[i]){
return i;
}
}
return 0;
}
/* the first pass records the address for each label */
void pass1(char *buffer) {
switch (buffer[0]) {
case 'i': here++; break;
case 'r': here++; break;
case 'd': here++; break;
case 's': here = here + strlen(buffer) - 1; break;
case ':': add_label(buffer+2, here); break;
}
}
/* the second pass assembles the instruction bundles */
void pass2(char *buffer) {
unsigned int opcode;
char inst[3];
inst[2] = '\0';
switch (buffer[0]) {
case 'i': memcpy(inst, buffer + 8, 2);
opcode = opcode_for(inst);
opcode = opcode << 8;
memcpy(inst, buffer + 6, 2);
opcode += opcode_for(inst);
opcode = opcode << 8;
memcpy(inst, buffer + 4, 2);
opcode += opcode_for(inst);
opcode = opcode << 8;
memcpy(inst, buffer + 2, 2);
opcode += opcode_for(inst);
target[here++] = opcode;
break;
case 'r': here++; break;
case 'd': here++; break;
case 's': here = here + strlen(buffer) - 1; break;
case ':': break;
}
}
/* the third pass assembles raw numeric values */
void pass3(char *buffer) {
switch (buffer[0]) {
case 'i': here++; break;
case 'r': here++; break;
case 'd': target[here++] = atoi(buffer+2); break;
case 's': here = here + strlen(buffer) - 1; break;
case ':': break;
}
}
/* the fourth pass assembles strings */
void pass4(char *buffer) {
unsigned int opcode;
switch (buffer[0]) {
case 'i': here++; break;
case 'r': here++; break;
case 'd': here++; break;
case 's': opcode = 2;
while (opcode < strlen(buffer)) {
target[here++] = buffer[opcode++];
}
target[here++] = 0;
break;
case ':': break;
}
}
/* the fifth pass resolves references to labels */
void pass5(char *buffer) {
switch (buffer[0]) {
case 'i': here++; break;
case 'r': target[here++] = lookup(buffer+2);
if (lookup(buffer+2) == -1)
printf("Lookup failed: '%s'\n", buffer+2);
break;
case 'd': here++; break;
case 's': here = here + strlen(buffer) - 1; break;
case ':': break;
}
}
int main(int argc, char **argv) {
int tests = 0;
int i = 1;
strcpy(code_start, "~~~");
strcpy(code_end, "~~~");
strcpy(test_start, "```");
strcpy(test_end, "```");
np = 0;
if (argc > 1) {
here = 0; unu(argv[1], 0, &pass1);
here = 0; unu(argv[1], 0, &pass2);
here = 0; unu(argv[1], 0, &pass3);
here = 0; unu(argv[1], 0, &pass4);
here = 0; unu(argv[1], 0, &pass5);
save();
printf("Wrote %lld cells to ngaImage\n", (long long)here);
}
else {
printf("No file specified.\n");
}
return 0;
}
/* *********************************************************************** */
/* GNU libc does not include the strl* functions available on BSD systems.
I include a copy of the OpenBSD implementation here as I'd rather use
the safer version of the functions. */
/*
* Copyright (c) 1998, 2015 Todd C. Miller <Todd.Miller@courtesan.com>
*
* 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 INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Copy string src to buffer dst of size dsize. At most dsize-1
* chars will be copied. Always NUL terminates (unless dsize == 0).
* Returns strlen(src); if retval >= dsize, truncation occurred.
*/
size_t bsd_strlcpy(char *dst, const char *src, size_t dsize)
{
const char *osrc = src;
size_t nleft = dsize;
/* Copy as many bytes as will fit. */
if (nleft != 0) {
while (--nleft != 0) {
if ((*dst++ = *src++) == '\0')
break;
}
}
/* Not enough room in dst, add NUL and traverse rest of src. */
if (nleft == 0) {
if (dsize != 0)
*dst = '\0'; /* NUL-terminate dst */
while (*src++)
;
}
return(src - osrc - 1); /* count does not include NUL */
}