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- /* m00adr.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 "6800.h"
-
- int
- addr(esp)
- register struct expr *esp;
- {
- register c;
- register struct area *espa;
-
- if ((c = getnb()) == '#') {
- expr(esp, 0);
- esp->e_mode = S_IMMED;
- } else if (c == ',') {
- esp->e_mode = S_INDX;
- esp->e_flag = 0;
- esp->e_addr = 0;
- esp->e_base.e_ap = NULL;
- if (admode(abx) != S_X)
- aerr();
- } else if (c == '*') {
- expr(esp, 0);
- esp->e_mode = S_DIR;
- espa = esp->e_base.e_ap;
- if (esp->e_addr & ~0xFF)
- aerr();
- if (espa && espa != sdp->s_area)
- rerr();
- if (more()) {
- comma();
- esp->e_mode = S_INDX;
- if (admode(abx) != S_X)
- aerr();
- }
- } else {
- unget(c);
- if (esp->e_mode = admode(abx)) {
- ;
- } else {
- expr(esp, 0);
- if (more()) {
- comma();
- esp->e_mode = S_INDX;
- if (admode(abx) != S_X)
- aerr();
- espa = esp->e_base.e_ap;
- if (esp->e_addr & ~0xFF)
- aerr();
- if (espa && espa != sdp->s_area)
- rerr();
- } else {
- if ( !esp->e_base.e_ap &&
- !(esp->e_addr & ~0xFF)) {
- esp->e_mode = S_DIR;
- } else {
- 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;
- unget(getnb());
- i = 0;
- while ( *(ptr = (char *) &sp[i].a_str) ) {
- if (srch(ptr)) {
- return(sp[i].a_val);
- }
- 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 abx[] = { /* a, b, or x registers */
- "a", S_A,
- "b", S_B,
- "x", S_X,
- "", 0x00
- };
-