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- /* m09adr.c */
-
- /*
- * (C) Copyright 1989
- * All Rights Reserved
- *
- * Alan R. Baldwin
- * 721 Berkeley St.
- * Kent, Ohio 44240
- */
-
- #include <stdio.h>
- #include <setjmp.h>
- #include "asm.h"
- #include "6809.h"
-
- int index;
-
- int
- addr(esp)
- register struct expr *esp;
- {
- register c;
-
- index = 0;
- if ((c = getnb()) == '#') {
- expr(esp, 0);
- esp->e_mode = S_IMMED;
- } else
- if (c == '[') {
- index = 0x90;
- addr1(esp);
- if (getnb() != ']') {
- aerr();
- }
- } else {
- unget(c);
- addr1(esp);
- }
- return (esp->e_mode);
- }
-
- int
- addr1(esp)
- register struct expr *esp;
- {
- register c;
-
- if (admode(abd)) {
- comma();
- if (!admode(xyus))
- aerr();
- esp->e_mode = S_IND;
- esp->e_flag = 0;
- esp->e_addr = 0;
- esp->e_base.e_ap = NULL;
- } else
- if ((c = getnb()) == ',') {
- if (admode(xyus)) {
- index |= 0x04;
- } else
- if (admode(auto2)) {
- ;
- } else
- if (!(index & 0x10) && admode(auto1)) {
- ;
- } else {
- aerr();
- }
- esp->e_mode = S_IND;
- esp->e_flag = 0;
- esp->e_addr = 0;
- esp->e_base.e_ap = NULL;
- } else
- if (c == '*') {
- expr(esp, 0);
- esp->e_mode = S_DIR;
- if ((c = getnb()) == ',') {
- if (admode(xyus)) {
- esp->e_mode = S_OFST;
- } else
- if (admode(pcr)) {
- esp->e_mode = S_PCR;
- } else
- if (admode(pc)) {
- esp->e_mode = S_PC;
- } else {
- aerr();
- }
- } else {
- unget(c);
- }
- } else {
- unget(c);
- expr(esp, 0);
- if ((c = getnb()) == ',') {
- if (admode(xyus)) {
- esp->e_mode = S_OFST;
- } else
- if (admode(pcr)) {
- esp->e_mode = S_PCR;
- } else
- if (admode(pc)) {
- esp->e_mode = S_PC;
- } else {
- aerr();
- }
- } else {
- unget(c);
- esp->e_mode = S_EXT;
- }
- }
- return (esp->e_mode);
- }
-
-
- /*
- * Enter admode() to search a specific addressing mode table
- * for a match. Return the addressing value on a match or
- * zero for no match.
- */
- int
- admode(sp)
- register struct adsym *sp;
- {
- register char *ptr;
- register int i, v;
- unget(getnb());
- i = 0;
- while ( *(ptr = (char *) &sp[i].a_str) ) {
- if (srch(ptr)) {
- v = sp[i].a_val;
- index |= (v | 0x80);
- return(v);
- }
- i++;
- }
- return(0);
- }
-
- /*
- * srch --- does string match ?
- */
- int
- srch(str)
- register char *str;
- {
- register char *ptr;
- ptr = ip;
-
- #if CASE_SENSITIVE
- while (*ptr && *str) {
- if (*ptr != *str)
- break;
- ptr++;
- str++;
- }
- if (*ptr == *str) {
- ip = ptr;
- return(1);
- }
- #else
- while (*ptr && *str) {
- if (ccase[*ptr] != ccase[*str])
- break;
- ptr++;
- str++;
- }
- if (ccase[*ptr] == ccase[*str]) {
- ip = ptr;
- return(1);
- }
- #endif
-
- if (!*str)
- if (any(*ptr," \t\n,];")) {
- ip = ptr;
- return(1);
- }
- return(0);
- }
-
- /*
- * any --- does str contain c?
- */
- int
- any(c,str)
- char c, *str;
- {
- while (*str)
- if(*str++ == c)
- return(1);
- return(0);
- }
-
- struct adsym abd[] = { /* a, b, or d indexed offset */
- "a", 0x06,
- "b", 0x05,
- "d", 0x0B,
- "", 0x00
- };
-
- struct adsym xyus[] = { /* x, y, u, or s index register */
- "x", 0x100,
- "y", 0x120,
- "u", 0x140,
- "s", 0x160,
- "", 0x000
- };
-
- struct adsym auto1[] = { /* auto increment/decrement by 1 */
- "x+", 0x100,
- "-x", 0x102,
- "y+", 0x120,
- "-y", 0x122,
- "u+", 0x140,
- "-u", 0x142,
- "s+", 0x160,
- "-s", 0x162,
- "", 0x000
- };
-
- struct adsym auto2[] = { /* auto increment/decrement by 2 */
- "x++", 0x101,
- "--x", 0x103,
- "y++", 0x121,
- "--y", 0x123,
- "u++", 0x141,
- "--u", 0x143,
- "s++", 0x161,
- "--s", 0x163,
- "", 0x000
- };
-
- struct adsym pc[] = { /* pc */
- "pc", 0x0C,
- "", 0x00
- };
-
- struct adsym pcr[] = { /* pc relative */
- "pcr", 0x0C,
- "", 0x00
- };
-
- struct adsym regs[] = { /* exg, tfr register coding */
- "d", 0x100,
- "x", 0x101,
- "y", 0x102,
- "u", 0x103,
- "s", 0x104,
- "pc", 0x105,
- "a", 0x108,
- "b", 0x109,
- "cc", 0x10A,
- "dp", 0x10B,
- "", 0x000
- };
-
- struct adsym stks[] = { /* push/pull on system stack */
- "cc", 0x01,
- "a", 0x02,
- "b", 0x04,
- "d", 0x06,
- "dp", 0x08,
- "x", 0x10,
- "y", 0x20,
- "u", 0x40,
- "pc", 0x80,
- "", 0x00
- };
-
- struct adsym stku[] = { /* push/pull on user stack */
- "cc", 0x01,
- "a", 0x02,
- "b", 0x04,
- "d", 0x06,
- "dp", 0x08,
- "x", 0x10,
- "y", 0x20,
- "s", 0x40,
- "pc", 0x80,
- "", 0x00
- };
-