Use the new code_props interface in parse-gram.y.

[bison.git] / src / scan-code.l

diff --git a/src/scan-code.l b/src/scan-code.l
index 70b250bc78c8bd1394bc6a1d40645edf7d524618..bf46e2da3e456dda22d9c8181094a60037496a1e 100644 (file)
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -1,6 +1,6 @@
 /* Bison Action Scanner                             -*- C -*-
 
 /* Bison Action Scanner                             -*- C -*-
 

-   Copyright (C) 2006 Free Software Foundation, Inc.
+   Copyright (C) 2006, 2007 Free Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 


@@ -31,28 +31,34 @@
 
 #define FLEX_PREFIX(Id) code_ ## Id
 #include "flex-scanner.h"
 
 #define FLEX_PREFIX(Id) code_ ## Id
 #include "flex-scanner.h"

+
+#include "complain.h"

 #include "reader.h"
 #include "getargs.h"
 #include "reader.h"
 #include "getargs.h"

-#include <assert.h>

 #include <get-errno.h>
 #include <quote.h>
 
 #include "scan-code.h"
 #include <get-errno.h>
 #include <quote.h>
 
 #include "scan-code.h"

+#include "symlist.h"

 
 /* The current calling start condition: SC_RULE_ACTION or
    SC_SYMBOL_ACTION. */
 
 /* The current calling start condition: SC_RULE_ACTION or
    SC_SYMBOL_ACTION. */

-# define YY_DECL const char *code_lex (int sc_context)
+# define YY_DECL static char *code_lex (code_props *self, int sc_context)

 YY_DECL;
 
 #define YY_USER_ACTION  location_compute (loc, &loc->end, yytext, yyleng);
 
 YY_DECL;
 
 #define YY_USER_ACTION  location_compute (loc, &loc->end, yytext, yyleng);
 

-static void handle_action_dollar (char *cp, location loc);
-static void handle_action_at (char *cp, location loc);
+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);

 static location the_location;
 static location *loc = &the_location;
 
 static location the_location;
 static location *loc = &the_location;
 

-/* The rule being processed. */
-symbol_list *current_rule;
+/* A string representing the most recent translation.  */
+static char *last_string;
+
+/* 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
 %}
  /* C and C++ comments in code. */
 %x SC_COMMENT SC_LINE_COMMENT


@@ -75,12 +81,15 @@ splice       (\\[ \f\t\v]*\n)*
 %%
 
 %{
 %%
 
 %{

+  /* Nesting level of the current code in braces.  */
+  int braces_level = 0;
+

   /* 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. */
   /* 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. */

-  assert (sc_context == SC_SYMBOL_ACTION
-         || sc_context == SC_RULE_ACTION
-         || sc_context == INITIAL);
+  aver (sc_context == SC_SYMBOL_ACTION
+       || sc_context == SC_RULE_ACTION
+       || sc_context == INITIAL);

   BEGIN sc_context;
 %}
 
   BEGIN sc_context;
 %}
 


@@ -146,8 +155,12 @@ splice      (\\[ \f\t\v]*\n)*
 
 <SC_RULE_ACTION>
 {
 
 <SC_RULE_ACTION>
 {

-  "$"("<"{tag}">")?(-?[0-9]+|"$")   handle_action_dollar (yytext, *loc);
-  "@"(-?[0-9]+|"$")                handle_action_at (yytext, *loc);
+  "$"("<"{tag}">")?(-?[0-9]+|"$")  {
+    handle_action_dollar (self->rule, yytext, *loc);
+  }
+  "@"(-?[0-9]+|"$") {
+    handle_action_at (self->rule, yytext, *loc);
+  }

 
   "$"  {
     warn_at (*loc, _("stray `$'"));
 
   "$"  {
     warn_at (*loc, _("stray `$'"));


@@ -157,11 +170,38 @@ splice     (\\[ \f\t\v]*\n)*
     warn_at (*loc, _("stray `@'"));
     obstack_sgrow (&obstack_for_string, "@@");
   }
     warn_at (*loc, _("stray `@'"));
     obstack_sgrow (&obstack_for_string, "@@");
   }

+
+  "{"  STRING_GROW; ++braces_level;
+  "}"  {
+    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, ';');
+
+    STRING_GROW;
+  }

 }
 
 <SC_SYMBOL_ACTION>
 {
 }
 
 <SC_SYMBOL_ACTION>
 {

-  "$$"   obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
+  "$$" {
+    obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
+    self->is_value_used = true;
+  }

   "@$"   obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
 }
 
   "@$"   obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
 }
 


@@ -186,8 +226,8 @@ splice       (\\[ \f\t\v]*\n)*
 
  /* End of processing. */
 <*><<EOF>>      {
 
  /* End of processing. */
 <*><<EOF>>      {

-                   obstack_1grow (&obstack_for_string, '\0');
-                  return obstack_finish (&obstack_for_string);
+                   STRING_FINISH;
+                   return last_string;

                  }
 
 %%
                  }
 
 %%


@@ -207,11 +247,23 @@ int max_left_semantic_context = 0;
 `------------------------------------------------------------------*/
 
 static void
 `------------------------------------------------------------------*/
 
 static void

-handle_action_dollar (char *text, location loc)
+handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)

 {
 {

-  const char *type_name = NULL;
+  char const *type_name = NULL;

   char *cp = text + 1;
   char *cp = text + 1;

-  int rule_length = symbol_list_length (current_rule->next);
+  symbol_list *effective_rule;
+  int effective_rule_length;
+
+  if (rule->midrule_parent_rule)
+    {
+      effective_rule = rule->midrule_parent_rule;
+      effective_rule_length = rule->midrule_parent_rhs_index - 1;
+    }
+  else
+    {
+      effective_rule = rule;
+      effective_rule_length = symbol_list_length (rule->next);
+    }

 
   /* Get the type name if explicit. */
   if (*cp == '<')
 
   /* Get the type name if explicit. */
   if (*cp == '<')


@@ -221,45 +273,70 @@ handle_action_dollar (char *text, location loc)
        ++cp;
       *cp = '\0';
       ++cp;
        ++cp;
       *cp = '\0';
       ++cp;

+      if (untyped_var_seen)
+       complain_at (dollar_loc, _("explicit type given in untyped grammar"));
+      tag_seen = true;

     }
 
   if (*cp == '$')
     {
       if (!type_name)
     }
 
   if (*cp == '$')
     {
       if (!type_name)

-       type_name = symbol_list_n_type_name_get (current_rule, loc, 0);
-      if (!type_name && typed)
-       complain_at (loc, _("$$ of `%s' has no declared type"),
-                    current_rule->sym->tag);
+       type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);
+

       if (!type_name)
       if (!type_name)

-       type_name = "";
+       {
+         if (union_seen | tag_seen)
+           {
+             if (rule->midrule_parent_rule)
+               complain_at (dollar_loc,
+                            _("$$ for the midrule at $%d of `%s'"
+                              " has no declared type"),
+                            rule->midrule_parent_rhs_index,
+                            effective_rule->content.sym->tag);
+             else
+               complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
+                            rule->content.sym->tag);
+           }
+         else
+           untyped_var_seen = true;
+         type_name = "";
+       }
+

       obstack_fgrow1 (&obstack_for_string,
                      "]b4_lhs_value([%s])[", type_name);
       obstack_fgrow1 (&obstack_for_string,
                      "]b4_lhs_value([%s])[", type_name);

-      current_rule->used = true;
+      rule->used = true;

     }
   else
     {
     }
   else
     {

-      long int num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);
-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
+      long int num = strtol (cp, NULL, 10);
+
+      if (1 - INT_MAX + effective_rule_length <= num
+         && num <= effective_rule_length)

        {
          int n = num;
        {
          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)
-           complain_at (loc, _("$%d of `%s' has no declared type"),
-                        n, current_rule->sym->tag);
+         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 (!type_name)

-           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])[",
          obstack_fgrow3 (&obstack_for_string,
                          "]b4_rhs_value(%d, %d, [%s])[",

-                         rule_length, n, type_name);
-         symbol_list_n_used_set (current_rule, n, true);
+                         effective_rule_length, n, type_name);
+          if (n > 0)
+            symbol_list_n_get (effective_rule, n)->used = true;

        }
       else
        }
       else

-       complain_at (loc, _("integer out of range: %s"), quote (text));
+       complain_at (dollar_loc, _("integer out of range: %s"), quote (text));

     }
 }
 
     }
 }
 


@@ -270,28 +347,31 @@ handle_action_dollar (char *text, location loc)
 `------------------------------------------------------*/
 
 static void
 `------------------------------------------------------*/
 
 static void

-handle_action_at (char *text, location loc)
+handle_action_at (symbol_list *rule, char *text, location at_loc)

 {
   char *cp = text + 1;
 {
   char *cp = text + 1;

-  int rule_length = symbol_list_length (current_rule->next);
+  int effective_rule_length =
+    (rule->midrule_parent_rule
+     ? rule->midrule_parent_rhs_index - 1
+     : symbol_list_length (rule->next));
+

   locations_flag = true;
 
   if (*cp == '$')
     obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
   else
     {
   locations_flag = true;
 
   if (*cp == '$')
     obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
   else
     {

-      long int num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);
+      long int num = strtol (cp, NULL, 10);

 
 

-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
+      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)[",
        {
          int n = num;
          obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",

-                         rule_length, n);
+                         effective_rule_length, n);

        }
       else
        }
       else

-       complain_at (loc, _("integer out of range: %s"), quote (text));
+       complain_at (at_loc, _("integer out of range: %s"), quote (text));

     }
 }
 
     }
 }
 


@@ -300,59 +380,111 @@ handle_action_at (char *text, location loc)
 | Initialize the scanner.  |
 `-------------------------*/
 
 | Initialize the scanner.  |
 `-------------------------*/
 

-/* Translate the dollars and ats in \a a, whose location is l.
-   Depending on the \a sc_context (SC_RULE_ACTION, SC_SYMBOL_ACTION,
-   INITIAL), the processing is different.  */
+/* Translate the dollars and ats in \a self, in the context \a sc_context
+   (SC_RULE_ACTION, SC_SYMBOL_ACTION, INITIAL).  */

 
 

-static const char *
-translate_action (int sc_context, const char *a, location l)
+static char const *
+translate_action (code_props *self, int sc_context)

 {
 {

-  const char *res;
+  char *res;

   static bool initialized = false;
   if (!initialized)
     {
       obstack_init (&obstack_for_string);
   static bool initialized = false;
   if (!initialized)
     {
       obstack_init (&obstack_for_string);

-      /* The initial buffer, never used. */
-      yy_delete_buffer (YY_CURRENT_BUFFER);

       yy_flex_debug = 0;
       initialized = true;
     }
 
       yy_flex_debug = 0;
       initialized = true;
     }
 

-  loc->start = loc->end = l.start;
-  yy_switch_to_buffer (yy_scan_string (a));
-  res = code_lex (sc_context);
+  loc->start = loc->end = self->location.start;
+  yy_switch_to_buffer (yy_scan_string (self->code));
+  res = code_lex (self, sc_context);

   yy_delete_buffer (YY_CURRENT_BUFFER);
 
   return res;
 }
 
   yy_delete_buffer (YY_CURRENT_BUFFER);
 
   return res;
 }
 

-const char *
-translate_rule_action (symbol_list *r, const char *a, location l)
+/*------------------------------------------------------------------------.
+| Implementation of the public interface as documented in "scan-code.h".  |
+`------------------------------------------------------------------------*/
+
+void
+code_props_none_init (code_props *self)
+{
+  *self = code_props_none;
+}
+
+code_props const code_props_none = CODE_PROPS_NONE_INIT;
+
+void
+code_props_plain_init (code_props *self, char const *code, location code_loc)
+{
+  self->kind = CODE_PROPS_PLAIN;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = NULL;
+}
+
+void
+code_props_symbol_action_init (code_props *self, char const *code,
+                               location code_loc)

 {
 {

-  current_rule = r;
-  return translate_action (SC_RULE_ACTION, a, l);
+  self->kind = CODE_PROPS_SYMBOL_ACTION;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = NULL;

 }
 
 }
 

-const char *
-translate_symbol_action (const char *a, location l)
+void
+code_props_rule_action_init (code_props *self, char const *code,
+                             location code_loc, symbol_list *rule)

 {
 {

-  return translate_action (SC_SYMBOL_ACTION, a, l);
+  self->kind = CODE_PROPS_RULE_ACTION;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = rule;

 }
 
 }
 

-const char *
-translate_code (const char *a, location l)
+void
+code_props_translate_code (code_props *self)

 {
 {

-  return translate_action (INITIAL, a, l);
+  switch (self->kind)
+    {
+      case CODE_PROPS_NONE:
+        break;
+      case CODE_PROPS_PLAIN:
+        self->code = translate_action (self, INITIAL);
+        break;
+      case CODE_PROPS_SYMBOL_ACTION:
+        self->code = translate_action (self, SC_SYMBOL_ACTION);
+        break;
+      case CODE_PROPS_RULE_ACTION:
+        self->code = translate_action (self, SC_RULE_ACTION);
+        break;
+    }

 }
 
 }
 

-/*-----------------------------------------------.
-| Free all the memory allocated to the scanner.  |
-`-----------------------------------------------*/
+void
+code_scanner_last_string_free (void)
+{
+  STRING_FREE;
+}

 
 void
 code_scanner_free (void)
 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */
 
 void
 code_scanner_free (void)
 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */

-  yy_delete_buffer (YY_CURRENT_BUFFER);
+  yylex_destroy ();
+}
+
+char const *
+translate_rule_action (symbol_list *rule)
+{
+  code_props cp;
+  code_props_rule_action_init (&cp, rule->action, rule->action_location, rule);
+  code_props_translate_code (&cp);
+  return cp.code;

 }
 }