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view lwasm/pragma.c @ 434:052c5f335a92
Fix bug in like terms collection in expression simplification
Like term collection would lose the actual "variable" part of the term if
the second term collected happened to have no coefficient. This would cause
the expression to take the value of the calculated coefficient which is
obviously wrong.
Thanks to hider <stego@satx.rr.com> for reporting the bug and providing a
proper test case.
Observation: this bug has been present since the first pre-release of
lwtools 3.0 when the algebraic expression system was introduced. Apparently
people tend not to create expressions that trigger the like terms handler.
The specific conditions require the symbol to be undefined and the second
operand to the addition has to have no coefficient so it's likely a fairly
rare scenario. Still, it is somewhat surprising that nobody tripped on it
before now.
author | William Astle <lost@l-w.ca> |
---|---|
date | Mon, 23 Jan 2017 22:58:36 -0700 |
parents | c501b3ce39c8 |
children | cad5937314cb |
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/* pragma.c Copyright © 2010 William Astle This file is part of LWTOOLS. LWTOOLS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <string.h> #include <ctype.h> #include <lw_string.h> #include <lw_alloc.h> #include "lwasm.h" #include "instab.h" #include "input.h" struct pragma_list { const char *setstr; const char *resetstr; int flag; }; struct pragma_stack_entry { int magic; // must always be at the start of any input stack entry int flag; // the pragma flag bit char str[1]; // magic number - this will be allocated bigger // string will be what's needed to re-instate a pragma }; static const struct pragma_list set_pragmas[] = { { "dollarnotlocal", "nodollarnotlocal", PRAGMA_DOLLARNOTLOCAL }, { "nodollarlocal", "dollarlocal", PRAGMA_DOLLARNOTLOCAL }, { "noindex0tonone", "index0tonone", PRAGMA_NOINDEX0TONONE }, { "undefextern", "noundefextern", PRAGMA_UNDEFEXTERN }, { "cescapes", "nocescapes", PRAGMA_CESCAPES }, { "importundefexport", "noimportundefexport", PRAGMA_IMPORTUNDEFEXPORT }, { "pcaspcr", "nopcaspcr", PRAGMA_PCASPCR }, { "shadow", "noshadow", PRAGMA_SHADOW }, { "nolist", "list", PRAGMA_NOLIST }, { "autobranchlength", "noautobranchlength", PRAGMA_AUTOBRANCHLENGTH }, { "export", "noexport", PRAGMA_EXPORT }, { "symbolnocase", "nosymbolnocase", PRAGMA_SYMBOLNOCASE }, { "nosymbolcase", "symbolcase", PRAGMA_SYMBOLNOCASE }, { "condundefzero", "nocondundefzero", PRAGMA_CONDUNDEFZERO }, { "6809", "6309", PRAGMA_6809 }, { "6800compat", "no6800compat", PRAGMA_6800COMPAT }, { "forwardrefmax", "noforwardrefmax", PRAGMA_FORWARDREFMAX }, { "testmode", "notestmode", PRAGMA_TESTMODE }, { "c", "noc", PRAGMA_C }, { "cc", "nocc", PRAGMA_CC }, { "cd", "nocd", PRAGMA_CD }, { "ct", "noct", PRAGMA_CT }, { "qrts", "noqrts", PRAGMA_QRTS }, { "m80ext", "nom80ext", PRAGMA_M80EXT }, { "6809conv", "no6809conv", PRAGMA_6809CONV }, { "6309conv", "no6309conv", PRAGMA_6309CONV }, { "newsource", "nonewsource", PRAGMA_NEWSOURCE }, { "nooldsource", "oldsource", PRAGMA_NEWSOURCE }, { 0, 0, 0 } }; int parse_pragma_helper(char *p) { int i; for (i = 0; set_pragmas[i].setstr; i++) { if (!strcasecmp(p, set_pragmas[i].setstr)) { return set_pragmas[i].flag; return 1; } if (!strcasecmp(p, set_pragmas[i].resetstr)) { return set_pragmas[i].flag | PRAGMA_CLEARBIT; return 2; } } return 0; } int parse_pragma_string(asmstate_t *as, char *str, int ignoreerr) { char *p; const char *np = str; int pragma; while (np) { p = lw_token(np, ',', &np); debug_message(as, 200, "Setting/resetting pragma %s", p); pragma = parse_pragma_helper(p); lw_free(p); if (pragma == 0 && !ignoreerr) return 0; if (pragma & PRAGMA_CLEARBIT) as->pragmas &= ~pragma; else as->pragmas |= pragma; } return 1; } PARSEFUNC(pseudo_parse_pragma) { char *ps, *t; for (t = *p; *t && !isspace(*t); t++) /* do nothing */ ; ps = lw_strndup(*p, t - *p); *p = t; l -> len = 0; if (parse_pragma_string(as, ps, 0) == 0) { lwasm_register_error(as, l, E_PRAGMA_UNRECOGNIZED); } if (as -> pragmas & PRAGMA_NOLIST) l -> pragmas |= PRAGMA_NOLIST; if (as->pragmas & PRAGMA_CC) { l->pragmas |= PRAGMA_CC; as->pragmas &= ~PRAGMA_CC; } lw_free(ps); } PARSEFUNC(pseudo_parse_starpragma) { char *ps, *t; for (t = *p; *t && !isspace(*t); t++) /* do nothing */ ; ps = lw_strndup(*p, t - *p); *p = t; l -> len = 0; // *pragma must NEVER throw an error parse_pragma_string(as, ps, 1); if (as -> pragmas & PRAGMA_NOLIST) l -> pragmas |= PRAGMA_NOLIST; if (as->pragmas & PRAGMA_CC) { l->pragmas |= PRAGMA_CC; as->pragmas &= ~PRAGMA_CC; } lw_free(ps); } static int pragma_stack_compare(input_stack_entry *e, void *d) { int flag = *((int *)d); struct pragma_stack_entry *pse = (struct pragma_stack_entry *)e; if (pse -> flag == flag) return 1; return 0; } PARSEFUNC(pseudo_parse_starpragmapop) { char *ps, *t; char *pp; int i; const char *np; struct pragma_stack_entry *pse; for (t = *p; *t && !isspace(*t); t++) /* do nothing */ ; ps = lw_strndup(*p, t - *p); *p = t; l -> len = 0; // *pragma stuff must never throw an error np = ps; while (np) { pp = lw_token(np, ',', &np); for (i = 0; set_pragmas[i].setstr; i++) { if (!strcasecmp(pp, set_pragmas[i].setstr) || !strcasecmp(pp, set_pragmas[i].resetstr)) { pse = (struct pragma_stack_entry *)input_stack_pop(as, 0x42424242, pragma_stack_compare, (void *)&(set_pragmas[i].flag)); if (pse) { debug_message(as, 100, "Popped pragma string %s", pse->str); parse_pragma_string(as, (char *)&(pse->str), 1); lw_free(pse); } if (set_pragmas[i].flag == PRAGMA_NOLIST) l -> pragmas |= PRAGMA_NOLIST; } } lw_free(pp); } lw_free(ps); } PARSEFUNC(pseudo_parse_starpragmapush) { char *ps, *t; char *pp; int i; const char *np; struct pragma_stack_entry *pse; for (t = *p; *t && !isspace(*t); t++) /* do nothing */ ; ps = lw_strndup(*p, t - *p); *p = t; l -> len = 0; // *pragma stuff must never throw an error np = ps; while (np) { pp = lw_token(np, ',', &np); for (i = 0; set_pragmas[i].setstr; i++) { if (!strcasecmp(pp, set_pragmas[i].setstr) || !strcasecmp(pp, set_pragmas[i].resetstr)) { /* found set or reset pragma */ /* push pragma state */ if (as -> pragmas & (set_pragmas[i].flag)) { /* use set string */ t = (char *)set_pragmas[i].setstr; } else { /* use reset string */ t = (char *)set_pragmas[i].resetstr; } pse = lw_alloc(sizeof(struct pragma_stack_entry) + strlen(t)); pse -> flag = set_pragmas[i].flag; pse -> magic = 0x42424242; strcpy((char *)&(pse -> str), t); debug_message(as, 100, "Pushed pragma string %s", pse->str); input_stack_push(as, (input_stack_entry *)pse); if (set_pragmas[i].flag == PRAGMA_NOLIST) l -> pragmas |= PRAGMA_NOLIST; } } lw_free(pp); } lw_free(ps); }