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GLR parsers sometimes raise parse errors instead of performing the

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default reduction.
Reported by Charles-Henry de Boysson.
* tests/calc.at (_AT_CHECK_CALC, _AT_CHECK_CALC_ERROR): Don't
check the length of the	traces when %glr.
(_AT_CHECK_CALC_ERROR): Also skip `^Stack' lines, coming from
GLR's traces.
(AT_CHECK_CALC_LALR, AT_CHECK_CALC_GLR): New.
Test GLR parsers.
* data/glr.c (YYLEFTMOST_STATE): Fix its value.
(yyltype): Remove the yy prefix from the member names.
(yytable): Complete its comment.
(yygetLRActions): Map error action number from YYTABLE from
YYTABLE_NINF to 0.
(yyisErrorAction): No longer compare YYACTION to YYPACT_NINF
(which was a bug: it should have been YYTABEL_NINF, and yet it was
not satisfying as we could compare an YYACTION computed from
YYDEFACT to YYTABLE_NINF although they are unrelated): 0 is the
only value for error actions.
(yyreportParseError): In verbose parse error messages, don't issue
`error' in the list of expected tokens.
* data/yacc.c (yyparse) <yybackup>: Rewrite the decoding of the
next action to perform to match glr.c's decoding.
(yytable): Complete its comment.
This commit is contained in:
Akim Demaille
2002-10-13 14:25:14 +00:00
parent 3b7d4eb2cd
commit f50adbbdb0
6 changed files with 213 additions and 129 deletions
Download Patch File Download Diff File Expand all files Collapse all files

52
data/glr.c
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@@ -169,10 +169,10 @@ typedef union b4_stype yystype;
typedef struct yyltype
{
]b4_location_if([
int yyfirst_line;
int yyfirst_column;
int yylast_line;
int yylast_column;])[
int first_line;
int first_column;
int last_line;
int last_column;])[
} yyltype;
# define YYLTYPE ]b4_ltype[
# define YYLTYPE_IS_TRIVIAL 1
@@ -333,7 +333,8 @@ static const ]b4_int_type_for([b4_pgoto])[ yypgoto[] =
/* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. If
positive, shift that token. If negative, reduce the rule which
number is the opposite. If zero, do what YYDEFACT says. */
number is the opposite. If zero, do what YYDEFACT says.
If YYTABLE_NINF, parse error. */
#define YYTABLE_NINF ]b4_table_ninf[
static const ]b4_int_type_for([b4_table])[ yytable[] =
{
@@ -396,10 +397,10 @@ int yyparse (void);
#ifndef YYLLOC_DEFAULT
# define YYLLOC_DEFAULT(yyCurrent, yyRhs, YYN) \
yyCurrent.yyfirst_line = YYRHSLOC(yyRhs,1).yyfirst_line; \
yyCurrent.yyfirst_column = YYRHSLOC(yyRhs,1).yyfirst_column; \
yyCurrent.yylast_line = YYRHSLOC(yyRhs,YYN).yylast_line; \
yyCurrent.yylast_column = YYRHSLOC(yyRhs,YYN).yylast_column;
yyCurrent.first_line = YYRHSLOC(yyRhs,1).first_line; \
yyCurrent.first_column = YYRHSLOC(yyRhs,1).first_column; \
yyCurrent.last_line = YYRHSLOC(yyRhs,YYN).last_line; \
yyCurrent.last_column = YYRHSLOC(yyRhs,YYN).last_column;
#endif
/* YYLEX -- calling `yylex' with the right arguments. */
@@ -705,16 +706,21 @@ yygetLRActions (yyStateNum yystate, int yytoken,
int* yyaction, const short** yyconflicts)
{
int yyindex = yypact[yystate] + yytoken;
if (yyindex < 0 || yyindex > YYLAST || yycheck[yyindex] != yytoken)
if (yyindex < 0 || YYLAST < yyindex || yycheck[yyindex] != yytoken)
{
*yyaction = -yydefact[yystate];
*yyconflicts = yyconfl;
}
else
else if (yytable[yyindex] != YYTABLE_NINF)
{
*yyaction = yytable[yyindex];
*yyconflicts = yyconfl + yyconflp[yyindex];
}
else
{
*yyaction = 0;
*yyconflicts = yyconfl + yyconflp[yyindex];
}
}
static inline yyStateNum
@@ -722,7 +728,7 @@ yyLRgotoState (yyStateNum yystate, yySymbol yylhs)
{
int yyr;
yyr = yypgoto[yylhs - YYNTOKENS] + yystate;
if (yyr >= 0 && yyr <= YYLAST && yycheck[yyr] == yystate)
if (0 <= yyr && yyr <= YYLAST && yycheck[yyr] == yystate)
return yytable[yyr];
else
return yydefgoto[yylhs - YYNTOKENS];
@@ -737,7 +743,7 @@ yyisShiftAction (int yyaction)
static inline bool
yyisErrorAction (int yyaction)
{
return yyaction == 0 || yyaction == YYPACT_NINF;
return yyaction == 0;
}
/* GLRStates */
@@ -1256,7 +1262,7 @@ yyresolveAction (yySemanticOption* yyopt, yyGLRStack* yystack,
}
#if YYDEBUG
static yyGLRState YYLEFTMOST_STATE = { 0, NULL, -1, 0, { NULL } };
static yyGLRState YYLEFTMOST_STATE = { 0, 0, -1, NULL, 0, { NULL } };
static void yyreportTree (yySemanticOption* yyx, int yyindent)
{
@@ -1524,7 +1530,7 @@ yyreportParseError (yyGLRStack* yystack, YYSTYPE* yylvalp, YYLTYPE* yyllocp)
{
yyprefix = ", expecting ";
for (yyx = yyn < 0 ? -yyn : 0; yyx < yytname_size; yyx += 1)
if (yycheck[yyx + yyn] == yyx)
if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR)
{
yyp += sprintf (yyp, "%s%s", yyprefix, yytokenName (yyx));
yyprefix = " or ";
@@ -1540,13 +1546,9 @@ yyreportParseError (yyGLRStack* yystack, YYSTYPE* yylvalp, YYLTYPE* yyllocp)
}
}
/* Recover from a syntax error on STACK, assuming that TOKENP,
/* Recover from a syntax error on YYSTACK, assuming that YYTOKENP,
YYLVALP, and YYLLOCP point to the syntactic category, semantic
value, and location of the lookahead.
NOTE: This uses the panic-mode recovery algorithm described in the
Bison documentation, which differs from what is in bison.simple.
Specifically, this routine performs no reductions before shifting
the error token. */
value, and location of the lookahead. */
static void
yyrecoverParseError (yyGLRStack* yystack, YYSTYPE* yylvalp, YYLTYPE* yyllocp)
{
@@ -1855,10 +1857,10 @@ b4_location_if(
[#ifndef YYLTYPE
typedef struct yyltype
{
int yyfirst_line;
int yyfirst_column;
int yylast_line;
int yylast_column;
int first_line;
int first_column;
int last_line;
int last_column;
} yyltype;
# define YYLTYPE yyltype
#endif