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regen

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This commit is contained in:
Akim Demaille
2020-01-17 06:51:24 +01:00
parent e1197fcc3d
commit c6e2dcabae
1 changed files with 105 additions and 66 deletions
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171
src/parse-gram.c
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@@ -1303,7 +1303,7 @@ do { \
{ \
YYDPRINTF ((stderr, \
"LAC: initial context established for %s\n", \
yysymbol_name(yytoken))); \
yysymbol_name (yytoken))); \
yy_lac_established = 1; \
{ \
int yy_lac_status = \
@@ -1356,7 +1356,7 @@ yy_lac (yy_state_t *yyesa, yy_state_t **yyes,
yy_state_t *yyes_prev = yyssp;
yy_state_t *yyesp = yyes_prev;
/* Reduce until we encounter a shift and thereby accept the token. */
YYDPRINTF ((stderr, "LAC: checking lookahead %s:", yysymbol_name(yytoken)));
YYDPRINTF ((stderr, "LAC: checking lookahead %s:", yysymbol_name (yytoken)));
if (yytoken == YYUNDEFTOK)
{
YYDPRINTF ((stderr, " Always Err\n"));
@@ -1454,6 +1454,91 @@ yy_lac (yy_state_t *yyesa, yy_state_t **yyes,
}
}
typedef struct
{
yy_state_t *yyssp;
int yytoken;
YYLTYPE *yylloc;
yy_state_t *yyesa;
yy_state_t **yyes_p;
YYPTRDIFF_T *yyes_capacity_p;
} yyparse_context_t;
/* Put in YYARG at most YYARGN of the expected tokens given the
current YYCTX, and return the number of tokens stored in YYARG. If
YYARG is null, return the number of expected tokens (guaranteed to
be less than YYNTOKENS). */
static int
yyexpected_tokens (const yyparse_context_t *yyctx,
int yyarg[], int yyargn)
{
/* Actual size of YYARG. */
int yycount = 0;
int yyx;
for (yyx = 0; yyx < YYNTOKENS; ++yyx)
if (yyx != YYTERROR && yyx != YYUNDEFTOK)
{
{
int yy_lac_status = yy_lac (yyctx->yyesa, yyctx->yyes_p, yyctx->yyes_capacity_p,
yyctx->yyssp, yyx);
if (yy_lac_status == 2)
return -2;
if (yy_lac_status == 1)
continue;
}
if (!yyarg)
++yycount;
else if (yycount == yyargn)
return 0;
else
yyarg[yycount++] = yyx;
}
return yycount;
}
static int
yysyntax_error_arguments (const yyparse_context_t *yyctx,
int yyarg[], int yyargn)
{
/* Actual size of YYARG. */
int yycount = 0;
/* There are many possibilities here to consider:
- If this state is a consistent state with a default action, then
the only way this function was invoked is if the default action
is an error action. In that case, don't check for expected
tokens because there are none.
- The only way there can be no lookahead present (in yychar) is if
this state is a consistent state with a default action. Thus,
detecting the absence of a lookahead is sufficient to determine
that there is no unexpected or expected token to report. In that
case, just report a simple "syntax error".
- Don't assume there isn't a lookahead just because this state is a
consistent state with a default action. There might have been a
previous inconsistent state, consistent state with a non-default
action, or user semantic action that manipulated yychar.
In the first two cases, it might appear that the current syntax
error should have been detected in the previous state when yy_lac
was invoked. However, at that time, there might have been a
different syntax error that discarded a different initial context
during error recovery, leaving behind the current lookahead.
*/
if (yyctx->yytoken != YYEMPTY)
{
int yyn;
YYDPRINTF ((stderr, "Constructing syntax error message\n"));
yyarg[yycount++] = yyctx->yytoken;
yyn = yyexpected_tokens (yyctx, yyarg ? yyarg + 1 : yyarg, yyargn - 1);
if (yyn == -2)
return -2;
else if (yyn == 0)
YYDPRINTF ((stderr, "No expected tokens.\n"));
else
yycount += yyn;
}
return yycount;
}
# ifndef yystrlen
# if defined __GLIBC__ && defined _STRING_H
@@ -1542,6 +1627,7 @@ yytnamerr (char *yyres, const char *yystr)
}
# endif
/* Copy into *YYMSG, which is of size *YYMSG_ALLOC, an error message
about the unexpected token YYTOKEN for the state stack whose top is
YYSSP. In order to see if a particular token T is a
@@ -1554,70 +1640,22 @@ yytnamerr (char *yyres, const char *yystr)
yy_lac returned 2. */
static int
yysyntax_error (YYPTRDIFF_T *yymsg_alloc, char **yymsg,
yy_state_t *yyesa, yy_state_t **yyes,
YYPTRDIFF_T *yyes_capacity, yy_state_t *yyssp, int yytoken)
const yyparse_context_t *yyctx)
{
enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
/* Internationalized format string. */
const char *yyformat = YY_NULLPTR;
/* Arguments of yyformat: reported tokens (one for the "unexpected",
one per "expected"). */
char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
/* Actual size of YYARG. */
int yycount = 0;
int yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
/* Cumulated lengths of YYARG. */
YYPTRDIFF_T yysize = 0;
/* There are many possibilities here to consider:
- If this state is a consistent state with a default action, then
the only way this function was invoked is if the default action
is an error action. In that case, don't check for expected
tokens because there are none.
- The only way there can be no lookahead present (in yychar) is if
this state is a consistent state with a default action. Thus,
detecting the absence of a lookahead is sufficient to determine
that there is no unexpected or expected token to report. In that
case, just report a simple "syntax error".
- Don't assume there isn't a lookahead just because this state is a
consistent state with a default action. There might have been a
previous inconsistent state, consistent state with a non-default
action, or user semantic action that manipulated yychar.
In the first two cases, it might appear that the current syntax
error should have been detected in the previous state when yy_lac
was invoked. However, at that time, there might have been a
different syntax error that discarded a different initial context
during error recovery, leaving behind the current lookahead.
*/
if (yytoken != YYEMPTY)
{
int yyn = yypact[+*yyssp];
YYDPRINTF ((stderr, "Constructing syntax error message\n"));
yyarg[yycount++] = yytname[yytoken];
if (!yypact_value_is_default (yyn))
{
int yyx;
for (yyx = 0; yyx < YYNTOKENS; ++yyx)
if (yyx != YYTERROR && yyx != YYUNDEFTOK)
{
{
int yy_lac_status = yy_lac (yyesa, yyes, yyes_capacity,
yyssp, yyx);
if (yy_lac_status == 2)
return 2;
if (yy_lac_status == 1)
continue;
}
if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
{
yycount = 1;
break;
}
yyarg[yycount++] = yytname[yyx];
}
}
else
YYDPRINTF ((stderr, "No expected tokens.\n"));
}
/* Actual size of YYARG. */
int yycount
= yysyntax_error_arguments (yyctx, yyarg, YYERROR_VERBOSE_ARGS_MAXIMUM);
if (yycount == -2)
return 2;
switch (yycount)
{
@@ -1642,7 +1680,8 @@ yysyntax_error (YYPTRDIFF_T *yymsg_alloc, char **yymsg,
int yyi;
for (yyi = 0; yyi < yycount; ++yyi)
{
YYPTRDIFF_T yysize1 = yysize + yytnamerr (YY_NULLPTR, yyarg[yyi]);
YYPTRDIFF_T yysize1
= yysize + yytnamerr (YY_NULLPTR, yytname[yyarg[yyi]]);
if (yysize <= yysize1 && yysize1 <= YYSTACK_ALLOC_MAXIMUM)
yysize = yysize1;
else
@@ -1668,7 +1707,7 @@ yysyntax_error (YYPTRDIFF_T *yymsg_alloc, char **yymsg,
while ((*yyp = *yyformat) != '\0')
if (*yyp == '%' && yyformat[1] == 's' && yyi < yycount)
{
yyp += yytnamerr (yyp, yyarg[yyi++]);
yyp += yytnamerr (yyp, yytname[yyarg[yyi++]]);
yyformat += 2;
}
else
@@ -2640,25 +2679,26 @@ yyerrlab:
if (!yyerrstatus)
{
++yynerrs;
# define YYSYNTAX_ERROR yysyntax_error (&yymsg_alloc, &yymsg, \
yyesa, &yyes, &yyes_capacity, \
yyssp, yytoken)
{
char const *yymsgp = YY_("syntax error");
yyparse_context_t yyctx
= {yyssp, yytoken, &yylloc, yyesa, &yyes, &yyes_capacity};
int yysyntax_error_status;
if (yychar != YYEMPTY)
YY_LAC_ESTABLISH;
yysyntax_error_status = YYSYNTAX_ERROR;
yysyntax_error_status = yysyntax_error (&yymsg_alloc, &yymsg, &yyctx);
if (yysyntax_error_status == 0)
yymsgp = yymsg;
else if (yysyntax_error_status == 1)
{
if (yymsg != yymsgbuf)
YYSTACK_FREE (yymsg);
yymsg = YY_CAST (char *, YYSTACK_ALLOC (YY_CAST (YYSIZE_T, yymsg_alloc)));
yymsg = YY_CAST (char *,
YYSTACK_ALLOC (YY_CAST (YYSIZE_T, yymsg_alloc)));
if (yymsg)
{
yysyntax_error_status = YYSYNTAX_ERROR;
yysyntax_error_status
= yysyntax_error (&yymsg_alloc, &yymsg, &yyctx);
yymsgp = yymsg;
}
else
@@ -2672,7 +2712,6 @@ yyerrlab:
if (yysyntax_error_status == 2)
goto yyexhaustedlab;
}
# undef YYSYNTAX_ERROR
}
yyerror_range[1] = yylloc;