(yyrecoverSyntaxError): Correct yyerrState logic. Correct comment.
Allow states with only a default reduction.
Fixes to avoid problem that $-N rules in GLR parsers can cause
buffer overruns, corrupting state.
* src/output.c (prepare_rules): Output max_left_semantic_context.
* src/reader.h (max_left_semantic_context): New
* src/scan-gram.l (max_left_semantic_context): Define.
(handle_action_dollar): Update max_left_semantic_context.
* data/glr.c (YYMAXLEFT): New.
(yydoAction): Increase yyrhsVals size.
(yyresolveAction): Ditto.
Fixes to problems with location handling in GLR parsers reported by
Frank Heckenbach (2003/06/05).
* data/glr.c (YYLTYPE): Make trivial if locations not used.
(YYRHSLOC): Add parentheses, make depend on whether locations used.
(YYLLOC_DEFAULT): Ditto.
(yyuserAction): Use YYLLOC_DEFAULT.
(yydoAction): Remove redundant code.
* tests/cxx-type.at: Exercise location information.
(yylex): Track locations.
(stmtMerge): Return value rather than printing.
+2003-06-09 Paul Hilfinger <Hilfinger@CS.Berkeley.EDU>
+
+ * data/glr.c (YYERROR): Update definition to reset yyerrState to 0
+ first.
+ (yyrecoverSyntaxError): Correct the logic for setting and testing
+ yyerrState.
+ Correct comment on handling EOF.
+ Allow states with only a default reduction, rather than failing
+ (I can't quite reconstruct why these were not allowed before).
+
+ Fixes to avoid problem that $-N rules in GLR parsers can cause
+ buffer overruns, corrupting state.
+
+ * src/output.c (prepare_rules): Output max_left_semantic_context
+ definition.
+ * src/reader.h (max_left_semantic_context): New variable declaration.
+ * src/scan-gram.l (max_left_semantic_context): Define.
+ (handle_action_dollar): Update max_left_semantic_context.
+ * data/glr.c (YYMAXLEFT): New definition.
+ (yydoAction): Increase size of yyrhsVals by YYMAXLEFT.
+ (yyresolveAction): Ditto.
+
+ Fixes to problems with location handling in GLR parsers reported by
+ Frank Heckenbach (2003/06/05).
+
+ * data/glr.c (YYLTYPE): Make trivial if locations not used.
+ (YYRHSLOC): Add parentheses, and define only if locations used.
+ (YYLLOC_DEFAULT): Add parentheses, and give trivial definition if
+ locations not used.
+ (yyuserAction): Use YYLLOC_DEFAULT to set *yylocp.
+ (yydoAction): Remove redundant initialization of *yyvalp and *yylocp.
+
+ * tests/cxx-type.at: Exercise location information; update tests
+ to differentiate output with and without locations.
+ Remove forward declarations of yylex and yyerror---caused errors
+ because default YYLTYPE not yet defined.
+ Change semantic actions to compute strings, rather than printing
+ them directly (to test proper passing of semantics values). Change
+ output to prefix notation and update test data and expected results.
+ (yylex): Track locations.
+ (stmtMerge): Return value rather than printing, and include arguments
+ in value.
+
2003-06-03 Paul Eggert <eggert@twinsun.com>
Avoid warnings generated by GCC 2.95.4 when Bison is
#if ! defined (YYLTYPE) && ! defined (YYLTYPE_IS_DECLARED)
typedef struct YYLTYPE
{
+]b4_location_if([
int first_line;
int first_column;
int last_line;
int last_column;
+])[
} YYLTYPE;
# define YYLTYPE_IS_DECLARED 1
# define YYLTYPE_IS_TRIVIAL 1
#define YYNSTATES ]b4_states_number[
/* YYMAXRHS -- Maximum number of symbols on right-hand side of rule. */
#define YYMAXRHS ]b4_r2_max[
+/* YYMAXLEFT -- Maximum number of symbols to the left of a handle
+ accessed by $0, $-1, etc., in any rule. */
+#define YYMAXLEFT ]b4_max_left_semantic_context[
/* YYTRANSLATE(X) -- Bison symbol number corresponding to X. */
#define YYUNDEFTOK ]b4_undef_token_number[
/* YYLLOC_DEFAULT -- Compute the default location (before the actions
are run). */
-#define YYRHSLOC(yyRhs,YYK) (yyRhs[YYK].yystate.yyloc)
+]b4_location_if([[
+#define YYRHSLOC(yyRhs,YYK) ((yyRhs)[YYK].yystate.yyloc)
#ifndef YYLLOC_DEFAULT
# define YYLLOC_DEFAULT(yyCurrent, yyRhs, YYN) \
- 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;
+ (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
+]],[
+#ifndef YYLLOC_DEFAULT
+# define YYLLOC_DEFAULT(yyCurrent, yyRhs, YYN)
#endif
+])[
+
/* YYLEX -- calling `yylex' with the right arguments. */
#define YYLEX ]b4_c_function_call([yylex], [int], b4_lex_param)[
yybool yynormal ATTRIBUTE_UNUSED = (yystack->yysplitPoint == NULL);
int yylow;
- if (yyrhslen == 0)
- {
- *yyvalp = yyval_default;
- *yylocp = yyloc_default;
- }
- else
- {
- *yyvalp = yyvsp[1-yyrhslen].yystate.yysemantics.yysval;
- *yylocp = yyvsp[1-yyrhslen].yystate.yyloc;
- }
# undef yyerrok
# define yyerrok (yystack->yyerrState = 0)
# undef YYACCEPT
# undef YYABORT
# define YYABORT return yyabort
# undef YYERROR
-# define YYERROR return yyerr
+# define YYERROR do { yystack->yyerrState = 0; return yyerr; } while (0)
# undef YYRECOVERING
# define YYRECOVERING (yystack->yyerrState != 0)
# undef yyclearin
YYERROR; \
} while (0)
+ yylow = 1;
+ if (yyrhslen == 0)
+ {
+ *yyvalp = yyval_default;
+ *yylocp = yyloc_default;
+ }
+ else
+ {
+ *yyvalp = yyvsp[YYFILL (1-yyrhslen)].yystate.yysemantics.yysval;
+ YYLLOC_DEFAULT (*yylocp, yyvsp - yyrhslen, yyrhslen);
+ }
+
]
- yylow = 1;
- switch (yyn)
- {
- b4_actions
- }
+ switch (yyn)
+ {
+ b4_actions
+ }
- return yyok;
+ return yyok;
# undef yyerrok
# undef YYABORT
# undef YYACCEPT
yystack->yynextFree -= yynrhs;
yystack->yyspaceLeft += yynrhs;
yystack->yytops.yystates[0] = & yystack->yynextFree[-1].yystate;
- if (yynrhs == 0)
- {
- *yyvalp = yyval_default;
- *yylocp = yyloc_default;
- }
- else
- {
- *yyvalp = rhs[1-yynrhs].yystate.yysemantics.yysval;
- *yylocp = rhs[1-yynrhs].yystate.yyloc;
- }
return yyuserAction (yyrule, yynrhs, rhs,
yyvalp, yylocp, yystack]b4_user_args[);
}
{
int yyi;
yyGLRState* yys;
- yyGLRStackItem yyrhsVals[YYMAXRHS+1];
- yys = yyrhsVals[YYMAXRHS].yystate.yypred = yystack->yytops.yystates[yyk];
+ yyGLRStackItem yyrhsVals[YYMAXRHS + YYMAXLEFT + 1];
+ yys = yyrhsVals[YYMAXRHS + YYMAXLEFT].yystate.yypred
+ = yystack->yytops.yystates[yyk];
for (yyi = 0; yyi < yynrhs; yyi += 1)
{
yys = yys->yypred;
}
yyupdateSplit (yystack, yys);
yystack->yytops.yystates[yyk] = yys;
- if (yynrhs == 0)
- {
- *yyvalp = yyval_default;
- *yylocp = yyloc_default;
- }
- else
- {
- *yyvalp = yyrhsVals[1].yystate.yysemantics.yysval;
- *yylocp = yyrhsVals[1].yystate.yyloc;
- }
- return yyuserAction (yyrule, yynrhs, yyrhsVals + YYMAXRHS - 1,
+ return yyuserAction (yyrule, yynrhs, yyrhsVals + YYMAXRHS + YYMAXLEFT - 1,
yyvalp, yylocp, yystack]b4_user_args[);
}
}
yyresolveAction (yySemanticOption* yyopt, yyGLRStack* yystack,
YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
{
- yyGLRStackItem yyrhsVals[YYMAXRHS+1];
+ yyGLRStackItem yyrhsVals[YYMAXRHS + YYMAXLEFT + 1];
int yynrhs;
yynrhs = yyrhsLength (yyopt->yyrule);
YYCHK (yyresolveStates (yyopt->yystate, yynrhs, yystack]b4_user_args[));
- yyrhsVals[YYMAXRHS].yystate.yypred = yyopt->yystate;
- return yyuserAction (yyopt->yyrule, yynrhs, yyrhsVals + YYMAXRHS - 1,
+ yyrhsVals[YYMAXRHS + YYMAXLEFT].yystate.yypred = yyopt->yystate;
+ return yyuserAction (yyopt->yyrule, yynrhs,
+ yyrhsVals + YYMAXRHS + YYMAXLEFT - 1,
yyvalp, yylocp, yystack]b4_user_args[);
}
size_t yyk;
int yyj;
- if (yystack->yyerrState == 0)
- yystack->yyerrState = 3;
- else if (yystack->yyerrState == 3)
+ if (yystack->yyerrState == 3)
/* We just shifted the error token and (perhaps) took some
reductions. Skip tokens until we can proceed. */
while (yytrue)
{
if (*yytokenp == YYEOF)
{
- /* Now pop stack until we find a state that shifts the
- error token. */
+ /* Now pop stack until empty and fail. */
while (yystack->yytops.yystates[0] != NULL)
{
yyGLRState *yys = yystack->yytops.yystates[0];
YYDSYMPRINTF ("Next token is", *yytokenp, yylvalp, yyllocp);
yyj = yypact[yystack->yytops.yystates[0]->yylrState];
if (yyis_pact_ninf (yyj))
- /* Something's not right; we shouldn't be here. */
- yyFail (yystack][]b4_lpure_args[, NULL);
+ return;
yyj += *yytokenp;
if (yyj < 0 || YYLAST < yyj || yycheck[yyj] != *yytokenp)
{
yycompressStack (yystack);
/* Now pop stack until we find a state that shifts the error token. */
+ yystack->yyerrState = 3;
while (yystack->yytops.yystates[0] != NULL)
{
yyGLRState *yys = yystack->yytops.yystates[0];
b4_pure_if([],
[extern YYSTYPE b4_prefix[]lval;])
-b4_location_if(
-[#if ! defined (YYLTYPE) && ! defined (YYLTYPE_IS_DECLARED)
+#if ! defined (YYLTYPE) && ! defined (YYLTYPE_IS_DECLARED)
typedef struct YYLTYPE
{
+b4_location_if([
int first_line;
int first_column;
int last_line;
int last_column;
+])
} YYLTYPE;
# define YYLTYPE_IS_DECLARED 1
# define YYLTYPE_IS_TRIVIAL 1
#endif
-m4_if(b4_pure, [0],
+b4_location_if([m4_if(b4_pure, [0],
[extern YYLTYPE b4_prefix[]lloc;])
])
])
muscle_insert_short_table ("merger", merger, 0, 0, nrules);
MUSCLE_INSERT_INT ("rules_number", nrules);
+ MUSCLE_INSERT_INT ("max_left_semantic_context", max_left_semantic_context);
free (rhs);
free (prhs);
extern FILE *gram_in;
extern int gram__flex_debug;
extern boundary scanner_cursor;
+extern int max_left_semantic_context;
void scanner_initialize (void);
void scanner_free (void);
void scanner_last_string_free (void);
%%
+/* Keeps track of the maximum number of semantic values to the left of
+ a handle (those referenced by $0, $-1, etc.) are required by the
+ semantic actions of this grammar. */
+int max_left_semantic_context = 0;
+
/* Set *LOC and adjust scanner cursor to account for token TOKEN of
size SIZE. */
if (INT_MIN <= num && num <= rule_length && ! get_errno ())
{
int n = num;
+ if (1-n > max_left_semantic_context)
+ max_left_semantic_context = 1-n;
if (!type_name && n > 0)
type_name = symbol_list_n_type_name_get (current_rule, loc, n);
if (!type_name && typed)
# and with RESOLVE1 and RESOLVE2 as annotations on the conflicted rule for
# stmt. Then compile the result.
m4_define([_AT_TEST_GLR_CXXTYPES],
-[AT_DATA_GRAMMAR([types.y],
+[
+AT_BISON_OPTION_PUSHDEFS([$1])
+
+AT_DATA_GRAMMAR([types.y],
[[/* Simplified C++ Type and Expression Grammar. */
$1
%{
#include <stdio.h>
#define YYSTYPE const char*
- #define YYLTYPE int
]m4_bmatch([$2], [stmtMerge],
[ static YYSTYPE stmtMerge (YYSTYPE x0, YYSTYPE x1);])[
#define YYINITDEPTH 10
- int yyerror (
-#if YYPURE && YYLSP_NEEDED
- YYLTYPE *yylocation,
-#endif
- const char *s
- );
-
- #if YYPURE
-]m4_bmatch([$1], [location],
-[ int yylex (YYSTYPE *lvalp, YYLTYPE *llocp);],
-[ int yylex (YYSTYPE *lvalp);])[
- #else
- int yylex (void);
- #endif
+ static char* format (const char*, ...);
%}
%%
prog :
- | prog stmt { printf ("\n"); }
+ | prog stmt {
+]AT_LOCATION_IF([
+ printf ("%d.%d-%d.%d: ",
+ @2.first_line, @2.first_column,
+ @2.last_line, @2.last_column);])[
+ printf ("%s\n", ]$[2);
+ }
;
-stmt : expr ';' $2
+stmt : expr ';' $2 { $$ = ]$[1; }
| decl $3
- | error ';'
- | '@' { YYACCEPT; }
+ | error ';' { $$ = "<error>"; }
+ | '@' { YYACCEPT; }
;
-expr : ID { printf ("%s ", ]$[1); }
- | TYPENAME '(' expr ')'
- { printf ("%s <cast> ", ]$[1); }
- | expr '+' expr { printf ("+ "); }
- | expr '=' expr { printf ("= "); }
+expr : ID
+ | TYPENAME '(' expr ')' { $$ = format ("<cast>(%s,%s)", ]$[3, ]$[1); }
+ | expr '+' expr { $$ = format ("+(%s,%s)", ]$[1, ]$[3); }
+ | expr '=' expr { $$ = format ("=(%s,%s)", ]$[1, ]$[3); }
;
decl : TYPENAME declarator ';'
- { printf ("%s <declare> ", ]$[1); }
+ { $$ = format ("<declare>(%s,%s)", ]$[1, ]$[2); }
| TYPENAME declarator '=' expr ';'
- { printf ("%s <init-declare> ", ]$[1); }
+ { $$ = format ("<init-declare>(%s,%s,%s)", ]$[1, ]$[2, ]$[4); }
;
-declarator : ID { printf ("\"%s\" ", ]$[1); }
- | '(' declarator ')'
+declarator : ID
+ | '(' declarator ')' { $$ = ]$[2; }
;
%%
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
+#include <stdarg.h>
int
main (int argc, char** argv)
exit (yyparse ());
}
-#if YYPURE
int
-]m4_bmatch([$1], [location],
-[yylex (YYSTYPE *lvalp, YYLTYPE *llocp)],
-[yylex (YYSTYPE *lvalp)])[
+#if YYPURE && YYLSP_NEEDED
+ yylex (YYSTYPE *lvalp, YYLTYPE *llocp)
+#elif YYPURE
+ yylex (YYSTYPE *lvalp)
#else
-int
-yylex ()
+ yylex ()
#endif
{
char buffer[256];
int c;
unsigned int i;
+ static int lineNum = 1;
+ static int colNum = 1;
+
#if YYPURE
+# define yylloc (*llocp)
# define yylval (*lvalp)
-]m4_bmatch([$1], [location],[ (void) llocp;])[
#endif
while (1)
{
case EOF:
return 0;
- case ' ': case '\t': case '\n': case '\f':
+ case '\t':
+ colNum = 1 + ((colNum + 7) & ~7);
+ break;
+ case ' ': case '\f':
+ colNum += 1;
+ break;
+ case '\n':
+ lineNum += 1;
+ colNum = 1;
break;
default:
- if (isalpha (c))
- {
- i = 0;
-
- do
- {
- buffer[i++] = c;
- if (i == sizeof buffer - 1)
- abort ();
- c = getchar ();
- }
- while (isalnum (c) || c == '_');
-
- ungetc (c, stdin);
- buffer[i++] = 0;
- yylval = strcpy (malloc (i), buffer);
- return isupper ((unsigned char) buffer[0]) ? TYPENAME : ID;
- }
- return c;
+ {
+ int tok;
+#if YYLSP_NEEDED
+ yylloc.first_line = yylloc.last_line = lineNum;
+ yylloc.first_column = colNum;
+#endif
+ if (isalpha (c))
+ {
+ i = 0;
+
+ do
+ {
+ buffer[i++] = c;
+ colNum += 1;
+ if (i == sizeof buffer - 1)
+ abort ();
+ c = getchar ();
+ }
+ while (isalnum (c) || c == '_');
+
+ ungetc (c, stdin);
+ buffer[i++] = 0;
+ tok = isupper ((unsigned char) buffer[0]) ? TYPENAME : ID;
+ yylval = strcpy (malloc (i), buffer);
+ }
+ else
+ {
+ colNum += 1;
+ tok = c;
+ yylval = "";
+ }
+#if YYLSP_NEEDED
+ yylloc.last_column = colNum-1;
+#endif
+ return tok;
+ }
}
}
}
int
yyerror (
#if YYPURE && YYLSP_NEEDED
- YYLTYPE *yylocation,
+ YYLTYPE *llocp,
#endif
const char *s
)
{
-#if YYPURE && YYLSP_NEEDED
- (void) *yylocation;
-#endif
fprintf (stderr, "%s\n", s);
return 0;
}
+
+static char* format (const char* form, ...)
+{
+ char buffer[1024];
+ va_list args;
+ va_start (args, form);
+ vsprintf (buffer, form, args);
+ va_end (args);
+ return strcpy (malloc (strlen (buffer) + 1), buffer);
+}
+
]]
m4_bmatch([$2], [stmtMerge],
[[static YYSTYPE
stmtMerge (YYSTYPE x0, YYSTYPE x1)
{
- /* Use the arguments. */
- (void) x0;
- (void) x1;
- printf ("<OR> ");
- return "";
+ return format ("<OR>(%s,%s)", x0, x1);
}
]])
)
AT_CHECK([bison -o types.c types.y], 0, [], ignore)
AT_COMPILE([types])
+AT_BISON_OPTION_POPDEFS
])
m4_define([_AT_RESOLVED_GLR_OUTPUT],
-[[z q +
-"x" T <declare>
-"x" y T <init-declare>
-x y =
-x T <cast> y +
-"x" T <declare>
-"y" z q + T <init-declare>
-y
-z q +
+[[+(z,q)
+<declare>(T,x)
+<init-declare>(T,x,y)
+=(x,y)
++(<cast>(x,T),y)
+<declare>(T,x)
+<init-declare>(T,y,+(z,q))
+<error>
++(z,q)
+]])
+
+m4_define([_AT_RESOLVED_GLR_OUTPUT_WITH_LOC],
+[[3.1-3.6: +(z,q)
+5.1-5.4: <declare>(T,x)
+7.1-7.8: <init-declare>(T,x,y)
+9.1-9.6: =(x,y)
+11.1-11.10: +(<cast>(x,T),y)
+13.1-13.6: <declare>(T,x)
+15.1-15.14: <init-declare>(T,y,+(z,q))
+17.6-17.16: <error>
+19.1-19.6: +(z,q)
]])
m4_define([_AT_AMBIG_GLR_OUTPUT],
-[[z q +
-"x" T <declare>
-"x" y T <init-declare>
-x y =
-x T <cast> y +
-"x" T <declare> x T <cast> <OR>
-"y" z q + T <init-declare> y T <cast> z q + = <OR>
-y
-z q +
+[[+(z,q)
+<declare>(T,x)
+<init-declare>(T,x,y)
+=(x,y)
++(<cast>(x,T),y)
+<OR>(<declare>(T,x),<cast>(x,T))
+<OR>(<init-declare>(T,y,+(z,q)),=(<cast>(y,T),+(z,q)))
+<error>
++(z,q)
+]])
+
+m4_define([_AT_AMBIG_GLR_OUTPUT_WITH_LOC],
+[[3.1-3.6: +(z,q)
+5.1-5.4: <declare>(T,x)
+7.1-7.8: <init-declare>(T,x,y)
+9.1-9.6: =(x,y)
+11.1-11.10: +(<cast>(x,T),y)
+13.1-13.6: <OR>(<declare>(T,x),<cast>(x,T))
+15.1-15.14: <OR>(<init-declare>(T,y,+(z,q)),=(<cast>(y,T),+(z,q)))
+17.6-17.16: <error>
+19.1-19.6: +(z,q)
]])
m4_define([_AT_GLR_STDERR],
AT_SETUP([GLR: Resolve ambiguity, impure, locations])
_AT_TEST_GLR_CXXTYPES([%locations],[%dprec 1],[%dprec 2])
AT_PARSER_CHECK([[./types test-input | sed 's/ *$//']], 0,
- _AT_RESOLVED_GLR_OUTPUT, _AT_GLR_STDERR)
+ _AT_RESOLVED_GLR_OUTPUT_WITH_LOC, _AT_GLR_STDERR)
AT_CLEANUP
AT_SETUP([GLR: Resolve ambiguity, pure, no locations])
_AT_TEST_GLR_CXXTYPES([%pure-parser %locations],
[%dprec 1], [%dprec 2])
AT_PARSER_CHECK([[./types test-input | sed 's/ *$//']], 0,
- _AT_RESOLVED_GLR_OUTPUT, _AT_GLR_STDERR)
+ _AT_RESOLVED_GLR_OUTPUT_WITH_LOC, _AT_GLR_STDERR)
AT_CLEANUP
AT_SETUP([GLR: Merge conflicting parses, impure, no locations])
_AT_TEST_GLR_CXXTYPES([%locations],
[%merge <stmtMerge>], [%merge <stmtMerge>])
AT_PARSER_CHECK([[./types test-input | sed 's/ *$//']], 0,
- _AT_AMBIG_GLR_OUTPUT, _AT_GLR_STDERR)
+ _AT_AMBIG_GLR_OUTPUT_WITH_LOC, _AT_GLR_STDERR)
AT_CLEANUP
AT_SETUP([GLR: Merge conflicting parses, pure, no locations])
_AT_TEST_GLR_CXXTYPES([%pure-parser %locations],
[%merge <stmtMerge>],[%merge <stmtMerge>])
AT_PARSER_CHECK([[./types test-input | sed 's/ *$//']], 0,
- _AT_AMBIG_GLR_OUTPUT, _AT_GLR_STDERR)
+ _AT_AMBIG_GLR_OUTPUT_WITH_LOC, _AT_GLR_STDERR)
AT_CLEANUP
AT_SETUP([GLR: Verbose messages, resolve ambiguity, impure, no locations])
projects / bison.git / commitdiff
