/* Bison Action Scanner -*- C -*-
- Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
#define code_wrap() 1
#define FLEX_PREFIX(Id) code_ ## Id
-#include "flex-scanner.h"
+#include <src/flex-scanner.h>
-#include "complain.h"
-#include "reader.h"
-#include "getargs.h"
+#include <src/complain.h>
+#include <src/reader.h>
+#include <src/getargs.h>
#include <get-errno.h>
#include <quote.h>
-
-#include "scan-code.h"
-#include "symlist.h"
+#include <src/muscle-tab.h>
+#include <src/scan-code.h>
+#include <src/symlist.h>
/* The current calling start condition: SC_RULE_ACTION or
SC_SYMBOL_ACTION. */
static void handle_action_dollar (symbol_list *rule, char *cp,
location dollar_loc);
static void handle_action_at (symbol_list *rule, char *cp, location at_loc);
+
+/* A string to be pushed to obstack after dollar/at has been handled */
+static char *ref_tail_fields;
+
static location the_location;
static location *loc = &the_location;
/* True if an untyped $$ or $n was seen. */
static bool untyped_var_seen;
+
%}
/* C and C++ comments in code. */
%x SC_COMMENT SC_LINE_COMMENT
white space between the backslash and the newline. */
splice (\\[ \f\t\v]*\n)*
+/* C style identifier. Must start with letter. Will be used for
+ named symbol references. */
+letter [-.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
+id {letter}({letter}|[0-9])*
+ref -?[0-9]+|{id}|"["{id}"]"|"$"
+
%%
%{
/* Nesting level of the current code in braces. */
int braces_level = 0;
+ /* Whether a semicolon is probably needed.
+ The heuristic is that a semicolon is not needed after `{', `}', `;',
+ or a C preprocessor directive, and that whitespaces and comments
+ do not affect this flag.
+ Note that `{' does not need a semicolon because of `{}'.
+ A semicolon may be needed before a cpp direcive, but don't bother. */
+ bool need_semicolon = false;
+
+ /* Whether in a C preprocessor directive. Don't use a start condition
+ for this because, at the end of strings and comments, we still need
+ to know whether we're in a directive. */
+ bool in_cpp = false;
+
/* This scanner is special: it is invoked only once, henceforth
is expected to return only once. This initialization is
therefore done once per action to translate. */
"'" {
STRING_GROW;
BEGIN SC_CHARACTER;
+ need_semicolon = true;
}
"\"" {
STRING_GROW;
BEGIN SC_STRING;
+ need_semicolon = true;
}
"/"{splice}"*" {
STRING_GROW;
<SC_RULE_ACTION>
{
- "$"("<"{tag}">")?(-?[0-9]+|"$") {
+ "$"("<"{tag}">")?{ref} {
+ ref_tail_fields = 0;
handle_action_dollar (self->rule, yytext, *loc);
+ if (ref_tail_fields != NULL) {
+ obstack_sgrow (&obstack_for_string, ref_tail_fields);
+ }
+ need_semicolon = true;
}
- "@"(-?[0-9]+|"$") {
+ "@"{ref} {
+ ref_tail_fields = 0;
handle_action_at (self->rule, yytext, *loc);
+ if (ref_tail_fields != NULL) {
+ obstack_sgrow (&obstack_for_string, ref_tail_fields);
+ }
+ need_semicolon = true;
}
-
"$" {
warn_at (*loc, _("stray `$'"));
obstack_sgrow (&obstack_for_string, "$][");
+ need_semicolon = true;
}
"@" {
warn_at (*loc, _("stray `@'"));
obstack_sgrow (&obstack_for_string, "@@");
+ need_semicolon = true;
+ }
+ "[" {
+ obstack_sgrow (&obstack_for_string, "@{");
+ need_semicolon = true;
+ }
+ "]" {
+ obstack_sgrow (&obstack_for_string, "@}");
+ need_semicolon = true;
}
- "{" STRING_GROW; ++braces_level;
+ ";" STRING_GROW; need_semicolon = false;
+ "{" STRING_GROW; ++braces_level; need_semicolon = false;
"}" {
bool outer_brace = --braces_level == 0;
/* As an undocumented Bison extension, append `;' before the last
brace in braced code, so that the user code can omit trailing
`;'. But do not append `;' if emulating Yacc, since Yacc does
- not append one.
-
- FIXME: Bison should warn if a semicolon seems to be necessary
- here, and should omit the semicolon if it seems unnecessary
- (e.g., after ';', '{', or '}', each followed by comments or
- white space). Such a warning shouldn't depend on --yacc; it
- should depend on a new --pedantic option, which would cause
- Bison to warn if it detects an extension to POSIX. --pedantic
- should also diagnose other Bison extensions like %yacc.
- Perhaps there should also be a GCC-style --pedantic-errors
- option, so that such warnings are diagnosed as errors. */
- if (outer_brace && ! yacc_flag)
- obstack_1grow (&obstack_for_string, ';');
+ not append one. */
+ if (outer_brace && !yacc_flag && language_prio == default_prio
+ && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
+ {
+ warn_at (*loc, _("a `;' might be needed at the end of action code"));
+ warn_at (*loc, _("future versions of Bison will not add the `;'"));
+ obstack_1grow (&obstack_for_string, ';');
+ }
STRING_GROW;
+ need_semicolon = false;
}
+
+ /* Preprocessing directives should only be recognized at the beginning
+ of lines, allowing whitespace including comments, but in C/C++,
+ `#' can only be the start of preprocessor directives or within
+ `#define' directives anyway, so don't bother with begin of line. */
+ "#" STRING_GROW; in_cpp = true;
+
+ {splice} STRING_GROW;
+ [\n\r] STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false;
+ [ \t\f] STRING_GROW;
+ . STRING_GROW; need_semicolon = true;
}
<SC_SYMBOL_ACTION>
}
"@$" {
obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
- locations_flag = true;
+ muscle_percent_define_ensure("locations", the_location, true);
}
}
%%
+
+static inline bool
+symbol_list_null(symbol_list *l)
+{
+ if (l && !(l->content_type == SYMLIST_SYMBOL && l->content.sym == NULL))
+ return false;
+ else
+ return true;
+}
+
+static inline bool
+is_dot_or_dash(char ch)
+{
+ return ch == '.' || ch == '-';
+}
+
+static inline bool
+is_digit(char ch)
+{
+ return '0' <= ch && ch <= '9';
+}
+
+static inline bool
+contains_dot_or_dash(const char* str)
+{
+ return strpbrk(str, ".-") != NULL;
+}
+
+#define VARIANT_HIDDEN (1 << 0)
+#define VARIANT_BAD_BRACKETING (1 << 1)
+#define VARIANT_NOT_VISIBLE_FROM_MIDRULE (1 << 2)
+
+typedef struct
+{
+ /* Index in symbol list. */
+ long int ind;
+
+ /* Matched symbol id and loc. */
+ uniqstr id;
+ location loc;
+
+ /* Hidding named reference. */
+ named_ref* hidden_by;
+
+ /* Error flags. */
+ unsigned err;
+} variant;
+
+static variant *variant_table = 0;
+static unsigned variant_table_size = 0;
+static unsigned variant_count = 0;
+
+static variant *
+variant_table_grow()
+{
+ ++variant_count;
+ if (variant_count > variant_table_size)
+ {
+ while (variant_count > variant_table_size)
+ variant_table_size = 2 * variant_table_size + 3;
+ variant_table = xnrealloc (variant_table, variant_table_size,
+ sizeof *variant_table);
+ }
+ return &variant_table[variant_count - 1];
+}
+
+static char *
+find_prefix_end(const char *prefix, char *begin, char *end)
+{
+ char *ptr = begin;
+
+ while (*prefix && ptr != end)
+ {
+ if (*prefix != *ptr)
+ return 0;
+ ++prefix, ++ptr;
+ }
+
+ if (*prefix)
+ return 0;
+
+ return ptr;
+}
+
+static variant *
+variant_add(uniqstr id, location loc, long int ind,
+ char *cp, char *cp_end, bool exact_mode)
+{
+ char *prefix_end;
+
+ prefix_end = find_prefix_end(id, cp, cp_end);
+ if (prefix_end &&
+ (prefix_end == cp_end ||
+ (!exact_mode && is_dot_or_dash(*prefix_end))))
+ {
+ variant *r = variant_table_grow();
+ r->ind = ind;
+ r->id = id;
+ r->loc = loc;
+ r->hidden_by = NULL;
+ r->err = 0;
+ return r;
+ }
+ else
+ return NULL;
+}
+
+#define INVALID_REF (INT_MIN)
+#define LHS_REF (INT_MIN + 1)
+
+static long int
+parse_named_ref(char *cp, symbol_list *rule, int rule_length,
+ int midrule_rhs_index, char *text, location loc,
+ char dollar_or_at)
+{
+ symbol_list *l;
+ char *cp_end;
+ bool exact_mode;
+ bool has_error;
+ bool has_valid;
+ long int ind, i;
+ variant* variant;
+ char* p;
+
+ if ('$' == *cp)
+ return LHS_REF;
+
+ if (is_digit (*cp) || (*cp == '-' && is_digit (* (cp + 1))))
+ {
+ long int num = strtol (cp, &cp, 10);
+ if (1 - INT_MAX + rule_length <= num && num <= rule_length)
+ return num;
+ else
+ {
+ complain_at (loc, _("integer out of range: %s"), quote (text));
+ return INVALID_REF;
+ }
+ }
+
+ if ('[' == *cp)
+ {
+ exact_mode = true;
+
+ /* Ignore the brackets. */
+ ++cp;
+ for (p = cp; *p != ']'; ++p);
+ cp_end = p;
+ }
+ else
+ {
+ exact_mode = false;
+
+ /* Take all characters of the name. */
+ for (p = cp; *p; ++p)
+ if (is_dot_or_dash(*p))
+ {
+ ref_tail_fields = p;
+ break;
+ }
+ for (p = cp; *p; ++p);
+ cp_end = p;
+ }
+
+ /* Add all relevant variants. */
+ variant_count = 0;
+ for (ind = 0, l = rule; !symbol_list_null(l); ++ind, l = l->next)
+ {
+ if (l->content_type != SYMLIST_SYMBOL)
+ continue;
+
+ variant = variant_add(l->content.sym->tag, l->sym_loc, ind,
+ cp, cp_end, exact_mode);
+
+ if (variant && l->named_ref)
+ variant->hidden_by = l->named_ref;
+
+ if (l->named_ref)
+ variant_add(l->named_ref->id, l->named_ref->loc, ind,
+ cp, cp_end, exact_mode);
+ }
+
+ /* Check errors. */
+ has_error = false;
+ has_valid = false;
+ for (i = 0; i < variant_count; ++i)
+ {
+ variant = &variant_table[i];
+ ind = variant->ind;
+
+ /* Check visibility from mid-rule actions. */
+ if (midrule_rhs_index != 0 &&
+ (ind == 0 || ind > midrule_rhs_index))
+ {
+ variant->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE;
+ has_error = true;
+ }
+
+ /* Check correct bracketing. */
+ if (!exact_mode && contains_dot_or_dash(variant->id))
+ {
+ variant->err |= VARIANT_BAD_BRACKETING;
+ has_error = true;
+ }
+
+ /* Check using of hidden symbols. */
+ if (variant->hidden_by != NULL)
+ {
+ variant->err |= VARIANT_HIDDEN;
+ has_error = true;
+ }
+
+ if (!variant->err)
+ has_valid = true;
+ }
+
+ if (variant_count == 1 && has_valid)
+ {
+ /* The only "good" case is here. */
+ ind = variant_table[0].ind;
+ if (ind == midrule_rhs_index)
+ return LHS_REF;
+ else
+ return ind;
+ }
+
+ /* Start complaining. */
+
+ if (variant_count == 0)
+ complain_at (loc, _("reference is invalid: %s, symbol not found"),
+ quote (text));
+ else if (variant_count > 1 && !has_error)
+ complain_at (loc, _("reference is ambiguous: %s"),
+ quote (text));
+ else if (variant_count > 1 && has_valid && has_error)
+ complain_at (loc, _("reference is misleading: %s"),
+ quote (text));
+ else
+ complain_at (loc, _("reference is invalid: %s"),
+ quote (text));
+
+ for (i = 0; i < variant_count; ++i)
+ {
+ static char at_buf[20];
+
+ variant = &variant_table[i];
+
+ if (variant->ind == 0)
+ strcpy(at_buf, "$$");
+ else
+ snprintf(at_buf, sizeof(at_buf), "$%ld", variant->ind);
+
+ if (variant->err == 0)
+ complain_at (variant->loc, _(" refers to: %c%s at %s"),
+ dollar_or_at, variant->id, at_buf);
+ else
+ {
+ static struct obstack msg_buf;
+ const char *tail = "";
+ const char *id;
+ location loc;
+
+ if (!exact_mode)
+ tail = cp + strlen(variant->id);
+
+ if (variant->hidden_by)
+ {
+ id = variant->hidden_by->id;
+ loc = variant->hidden_by->loc;
+ }
+ else
+ {
+ id = variant->id;
+ loc = variant->loc;
+ }
+
+ /* Create the explanation message. */
+
+ obstack_init (&msg_buf);
+
+ obstack_fgrow1 (&msg_buf, " possibly meant: %c", dollar_or_at);
+ if (contains_dot_or_dash (id))
+ obstack_fgrow1 (&msg_buf, "[%s]", id);
+ else
+ obstack_sgrow (&msg_buf, id);
+ obstack_sgrow (&msg_buf, tail);
+
+ if (variant->err & VARIANT_HIDDEN)
+ {
+ obstack_fgrow1 (&msg_buf, ", hiding %c", dollar_or_at);
+ if (contains_dot_or_dash (variant->id))
+ obstack_fgrow1 (&msg_buf, "[%s]", variant->id);
+ else
+ obstack_sgrow (&msg_buf, variant->id);
+ obstack_sgrow (&msg_buf, tail);
+ }
+
+ obstack_fgrow1 (&msg_buf, " at %s", at_buf);
+
+ if (variant->err & VARIANT_NOT_VISIBLE_FROM_MIDRULE)
+ obstack_fgrow1 (&msg_buf, ", cannot be accessed from "
+ "mid-rule action at $%d", midrule_rhs_index);
+
+ obstack_1grow (&msg_buf, '\0');
+ complain_at (loc, _("%s"), (char *) obstack_finish (&msg_buf));
+ obstack_free (&msg_buf, 0);
+ }
+ }
+
+ return INVALID_REF;
+}
+
/* Keeps track of the maximum number of semantic values to the left of
a handle (those referenced by $0, $-1, etc.) are required by the
semantic actions of this grammar. */
{
char const *type_name = NULL;
char *cp = text + 1;
+ char *gt_ptr = 0;
symbol_list *effective_rule;
- int effective_rule_length;
+ int effective_rule_length, n;
if (rule->midrule_parent_rule)
{
type_name = ++cp;
while (*cp != '>')
++cp;
- *cp = '\0';
+
+ /* The '>' symbol will be later replaced by '\0'. Original
+ 'text' is needed for error messages. */
+ gt_ptr = cp;
++cp;
if (untyped_var_seen)
complain_at (dollar_loc, _("explicit type given in untyped grammar"));
tag_seen = true;
}
- if (*cp == '$')
+ n = parse_named_ref (cp, effective_rule, effective_rule_length,
+ rule->midrule_parent_rhs_index, text, dollar_loc, '$');
+
+ if (gt_ptr)
+ *gt_ptr = '\0';
+
+ switch (n)
{
+ case INVALID_REF:
+ break;
+
+ case LHS_REF:
if (!type_name)
type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);
obstack_fgrow1 (&obstack_for_string,
"]b4_lhs_value([%s])[", type_name);
rule->action_props.is_value_used = true;
- }
- else
- {
- long int num = strtol (cp, NULL, 10);
-
- if (1 - INT_MAX + effective_rule_length <= num
- && num <= effective_rule_length)
+ break;
+
+ default:
+ if (max_left_semantic_context < 1 - n)
+ max_left_semantic_context = 1 - n;
+ if (!type_name && 0 < n)
+ type_name =
+ symbol_list_n_type_name_get (effective_rule, dollar_loc, n);
+ if (!type_name)
{
- int n = num;
- if (max_left_semantic_context < 1 - n)
- max_left_semantic_context = 1 - n;
- if (!type_name && 0 < n)
- type_name =
- symbol_list_n_type_name_get (effective_rule, dollar_loc, n);
- if (!type_name)
- {
- if (union_seen | tag_seen)
- complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
- n, effective_rule->content.sym->tag);
- else
- untyped_var_seen = true;
- type_name = "";
- }
-
- obstack_fgrow3 (&obstack_for_string,
- "]b4_rhs_value(%d, %d, [%s])[",
- effective_rule_length, n, type_name);
- if (n > 0)
- symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
- true;
+ if (union_seen | tag_seen)
+ complain_at (dollar_loc, _("$%s of `%s' has no declared type"),
+ cp, effective_rule->content.sym->tag);
+ else
+ untyped_var_seen = true;
+ type_name = "";
}
- else
- complain_at (dollar_loc, _("integer out of range: %s"), quote (text));
+
+ obstack_fgrow3 (&obstack_for_string,
+ "]b4_rhs_value(%d, %d, [%s])[",
+ effective_rule_length, n, type_name);
+ if (n > 0)
+ symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
+ true;
+ break;
}
}
handle_action_at (symbol_list *rule, char *text, location at_loc)
{
char *cp = text + 1;
- int effective_rule_length =
- (rule->midrule_parent_rule
- ? rule->midrule_parent_rhs_index - 1
- : symbol_list_length (rule->next));
-
- locations_flag = true;
+ symbol_list *effective_rule;
+ int effective_rule_length, n;
- if (*cp == '$')
- obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
+ if (rule->midrule_parent_rule)
+ {
+ effective_rule = rule->midrule_parent_rule;
+ effective_rule_length = rule->midrule_parent_rhs_index - 1;
+ }
else
{
- long int num = strtol (cp, NULL, 10);
+ effective_rule = rule;
+ effective_rule_length = symbol_list_length (rule->next);
+ }
- if (1 - INT_MAX + effective_rule_length <= num
- && num <= effective_rule_length)
- {
- int n = num;
- obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",
- effective_rule_length, n);
- }
- else
- complain_at (at_loc, _("integer out of range: %s"), quote (text));
+ muscle_percent_define_ensure("locations", at_loc, true);
+
+ n = parse_named_ref (cp, effective_rule, effective_rule_length,
+ rule->midrule_parent_rhs_index, text, at_loc, '@');
+ switch (n)
+ {
+ case INVALID_REF:
+ break;
+
+ case LHS_REF:
+ obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
+ break;
+
+ default:
+ obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",
+ effective_rule_length, n);
+ break;
}
}
self->location = code_loc;
self->is_value_used = false;
self->rule = NULL;
+ self->named_ref = NULL;
}
void
self->location = code_loc;
self->is_value_used = false;
self->rule = NULL;
+ self->named_ref = NULL;
}
void
code_props_rule_action_init (code_props *self, char const *code,
- location code_loc, symbol_list *rule)
+ location code_loc, symbol_list *rule,
+ named_ref *named_ref)
{
self->kind = CODE_PROPS_RULE_ACTION;
self->code = code;
self->location = code_loc;
self->is_value_used = false;
self->rule = rule;
+ self->named_ref = named_ref;
}
void
projects / bison.git / blobdiff