Lemon update 2016-05-24 18:55:08 on branch trunk

— Enhance Lemon and the parser template so that it can once again build
parsers that have no unreachable branches. (user: drh)
This commit is contained in:
Marisa Heit 2016-10-13 22:18:20 -05:00
parent 64bd551d20
commit 96afce241d

View file

@ -198,6 +198,7 @@ struct rule {
int index; /* An index number for this rule */
int iRule; /* Rule number as used in the generated tables */
Boolean canReduce; /* True if this rule is ever reduced */
Boolean doesReduce; /* Reduce actions occur after optimization */
struct rule *nextlhs; /* Next rule with the same LHS */
struct rule *next; /* Next rule in the global list */
};
@ -4154,6 +4155,19 @@ void ReportTable(
}
free(ax);
/* Mark rules that are actually used for reduce actions after all
** optimizations have been applied
*/
for(rp=lemp->rule; rp; rp=rp->next) rp->doesReduce = LEMON_FALSE;
for(i=0; i<lemp->nxstate; i++){
struct action *ap;
for(ap=lemp->sorted[i]->ap; ap; ap=ap->next){
if( ap->type==REDUCE || ap->type==SHIFTREDUCE ){
ap->x.rp->doesReduce = i;
}
}
}
/* Finish rendering the constants now that the action table has
** been computed */
fprintf(out,"#define YYNSTATE %d\n",lemp->nxstate); lineno++;
@ -4445,7 +4459,12 @@ void ReportTable(
assert( rp->noCode );
fprintf(out," /* (%d) ", rp->iRule);
writeRuleText(out, rp);
fprintf(out," */ yytestcase(yyruleno==%d);\n", rp->iRule); lineno++;
if( rp->doesReduce ){
fprintf(out, " */ yytestcase(yyruleno==%d);\n", rp->iRule); lineno++;
}else{
fprintf(out, " (OPTIMIZED OUT) */ assert(yyruleno!=%d);\n",
rp->iRule); lineno++;
}
}
fprintf(out," break;\n"); lineno++;
tplt_xfer(lemp->name,in,out,&lineno);