Bench the three-stack lalr1.cc.

[bison.git] / data / lalr1.cc

diff --git a/data/lalr1.cc b/data/lalr1.cc
index 07a301ffe8209e05703012b1125b6adc847f3f89..7195c28d015a3089bb623ca3d9ce6933afa72165 100644 (file)
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -18,6 +18,94 @@
 
 m4_include(b4_pkgdatadir/[c++.m4])
 
 
 m4_include(b4_pkgdatadir/[c++.m4])
 

+# How the semantic value is extracted when using variants.
+b4_variant_if([
+  # b4_symbol_value(VAL, [TYPE])
+  # ----------------------------
+  m4_define([b4_symbol_value],
+  [m4_ifval([$2],
+            [$1.as<$2>()],
+            [$1])])
+]) # b4_variant_if
+
+
+# b4_symbol_actions(FILENAME, LINENO,
+#                   SYMBOL-TAG, SYMBOL-NUM,
+#                   SYMBOL-ACTION, SYMBOL-TYPENAME)
+# -------------------------------------------------
+# Same as in C, but using references instead of pointers.
+m4_define([b4_symbol_actions],
+[m4_pushdef([b4_dollar_dollar],
+            [b4_symbol_value([yyvalue], [$6])])dnl
+m4_pushdef([b4_at_dollar], [yylocation])dnl
+      case $4: // $3
+b4_syncline([$2], [$1])
+        $5;
+b4_syncline([@oline@], [@ofile@])
+        break;
+m4_popdef([b4_at_dollar])dnl
+m4_popdef([b4_dollar_dollar])dnl
+])
+
+
+# b4_symbol_action_(SYMBOL-TAG, SYMBOL-NUM, SYMBOL-TYPENAME)
+# ----------------------------------------------------------
+# Invoke b4_dollar_dollar(SYMBOL_TYPENAME) for each symbol.
+m4_define([b4_symbol_action_],
+[m4_ifval($3,
+[      case $2: // $1
+        b4_dollar_dollar($@);
+       break;
+])])
+
+
+# b4_symbol_variant(YYTYPE, YYVAL, ACTION)
+# ----------------------------------------
+# Run some ACTION ("build", or "destroy") on YYVAL of symbol type
+# YYTYPE.
+m4_define([b4_symbol_variant],
+[m4_pushdef([b4_dollar_dollar],
+            [$2.$3<$][3>()])dnl
+  switch ($1)
+    {
+m4_map([b4_symbol_action_], m4_defn([b4_type_names]))
+     default:
+       break;
+    }
+m4_popdef([b4_dollar_dollar])dnl
+])
+
+
+# _b4_char_sizeof_counter
+# -----------------------
+# A counter used by _b4_char_sizeof_dummy to create fresh symbols.
+m4_define([_b4_char_sizeof_counter],
+[0])
+
+# _b4_char_sizeof_dummy
+# ---------------------
+# At each call return a new C++ identifier.
+m4_define([_b4_char_sizeof_dummy],
+[m4_define([_b4_char_sizeof_counter], m4_incr(_b4_char_sizeof_counter))dnl
+dummy[]_b4_char_sizeof_counter])
+
+
+# b4_char_sizeof(SYMBOL-TAG, SYMBOL-NUM, SYMBOL-TYPENAME)
+# -------------------------------------------------------
+# To be mapped on the list of type names to produce:
+#
+#    char dummy1[sizeof(type_name_1)];
+#    char dummy2[sizeof(type_name_2)];
+#
+# for defined type names.
+# $3 is doubly-quoted, do not quote it again.
+m4_define([b4_char_sizeof],
+[m4_ifval($3,
+[
+      char _b4_char_sizeof_dummy@{sizeof($3)@}; // $1])dnl
+])
+
+

 m4_define([b4_parser_class_name],
           [b4_percent_define_get([[parser_class_name]])])
 
 m4_define([b4_parser_class_name],
           [b4_percent_define_get([[parser_class_name]])])
 


@@ -52,6 +140,51 @@ dnl FIXME: This is wrong, we want computed header guards.
 ]b4_namespace_open[
   class position;
   class location;
 ]b4_namespace_open[
   class position;
   class location;

+]b4_variant_if([[
+  /// A char[S] buffer to store and retrieve objects.
+  ///
+  /// Sort of a variant, but does not keep track of the nature
+  /// of the stored data, since that knowledge is available
+  /// via the current state.
+  template <size_t S>
+  struct variant
+  {
+    /// Instantiate a \a T in here.
+    template <typename T>
+    inline void
+    build()
+    {
+      new (buffer) T;
+    }
+
+    /// Destroy the stored \a T.
+    template <typename T>
+    inline void
+    destroy()
+    {
+      reinterpret_cast<T&>(buffer).~T();
+    }
+
+    /// Accessor to a built \a T.
+    template <typename T>
+    inline T&
+    as()
+    {
+      return reinterpret_cast<T&>(buffer);
+    }
+
+    /// Const accessor to a built \a T (for %printer).
+    template <typename T>
+    inline const T&
+    as() const
+    {
+      return reinterpret_cast<const T&>(buffer);
+    }
+
+    /// A buffer large enough to store any of the semantic values.
+    char buffer[S];
+  };
+]])[

 ]b4_namespace_close[
 
 #include "location.hh"
 ]b4_namespace_close[
 
 #include "location.hh"


@@ -99,16 +232,23 @@ do {                                                       \
   class ]b4_parser_class_name[
   {
   public:
   class ]b4_parser_class_name[
   {
   public:

-    /// Symbol semantic values.

 #ifndef YYSTYPE
 #ifndef YYSTYPE

-]m4_ifdef([b4_stype],
+]b4_variant_if(
+[    /// An auxiliary type to compute the largest semantic type.
+    union union_type
+    {]m4_map([b4_char_sizeof], m4_defn([b4_type_names]))[
+    };
+
+    /// Symbol semantic values.
+    typedef variant<sizeof(union_type)> semantic_type;],
+[    /// Symbol semantic values.
+m4_ifdef([b4_stype],

 [    union semantic_type
 [    union semantic_type

-    {
-b4_user_stype
+    {b4_user_stype

     };],
 [m4_if(b4_tag_seen_flag, 0,
 [[    typedef int semantic_type;]],
     };],
 [m4_if(b4_tag_seen_flag, 0,
 [[    typedef int semantic_type;]],

-[[    typedef YYSTYPE semantic_type;]])])[
+[[    typedef YYSTYPE semantic_type;]])])])[

 #else
     typedef YYSTYPE semantic_type;
 #endif
 #else
     typedef YYSTYPE semantic_type;
 #endif


@@ -159,18 +299,18 @@ b4_error_verbose_if([, int tok])[);
 #if YYDEBUG
     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.
 #if YYDEBUG
     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     virtual void yy_symbol_value_print_ (int yytype,
     virtual void yy_symbol_value_print_ (int yytype,

-                                        const semantic_type* yyvaluep,
-                                        const location_type* yylocationp);
+                                        const semantic_type& yyvalue,
+                                        const location_type& yylocation);

     /// \brief Report a symbol on the debug stream.
     /// \param yytype       The token type.
     /// \brief Report a symbol on the debug stream.
     /// \param yytype       The token type.

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     virtual void yy_symbol_print_ (int yytype,
     virtual void yy_symbol_print_ (int yytype,

-                                  const semantic_type* yyvaluep,
-                                  const location_type* yylocationp);
+                                  const semantic_type& yyvalue,
+                                  const location_type& yylocation);

 #endif
 
 
 #endif
 
 


@@ -260,12 +400,17 @@ b4_error_verbose_if([, int tok])[);
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg        Why this token is reclaimed.
     /// \param yytype       The symbol type.
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg        Why this token is reclaimed.
     /// \param yytype       The symbol type.

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     inline void yydestruct_ (const char* yymsg,
                             int yytype,
     inline void yydestruct_ (const char* yymsg,
                             int yytype,

-                            semantic_type* yyvaluep,
-                            location_type* yylocationp);
+                            semantic_type& yyvalue,
+                            location_type& yylocation);
+
+    /// Push a new state on the stack.
+    /// \warning the contents of \a v is stolen.
+    inline void yypush_ (state_type s,
+                         semantic_type& v, const location_type& l);

 
     /// Pop \a n symbols the three stacks.
     inline void yypop_ (unsigned int n = 1);
 
     /// Pop \a n symbols the three stacks.
     inline void yypop_ (unsigned int n = 1);


@@ -440,10 +585,10 @@ do {                                      \
 
   inline void
   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 
   inline void
   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,

-                          const semantic_type* yyvaluep, const location_type* yylocationp)
+                          const semantic_type& yyvalue, const location_type& yylocation)

   {
   {

-    YYUSE (yylocationp);
-    YYUSE (yyvaluep);
+    YYUSE (yylocation);
+    YYUSE (yyvalue);

     switch (yytype)
       {
   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
     switch (yytype)
       {
   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl


@@ -455,25 +600,25 @@ do {                                      \
 
   void
   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 
   void
   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,

-                          const semantic_type* yyvaluep, const location_type* yylocationp)
+                          const semantic_type& yyvalue, const location_type& yylocation)

   {
     *yycdebug_ << (yytype < yyntokens_ ? "token" : "nterm")
               << ' ' << yytname_[yytype] << " ("
   {
     *yycdebug_ << (yytype < yyntokens_ ? "token" : "nterm")
               << ' ' << yytname_[yytype] << " ("

-              << *yylocationp << ": ";
-    yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
+              << yylocation << ": ";
+    yy_symbol_value_print_ (yytype, yyvalue, yylocation);

     *yycdebug_ << ')';
   }
 #endif
 
   void
   ]b4_parser_class_name[::yydestruct_ (const char* yymsg,
     *yycdebug_ << ')';
   }
 #endif
 
   void
   ]b4_parser_class_name[::yydestruct_ (const char* yymsg,

-                          int yytype, semantic_type* yyvaluep, location_type* yylocationp)
+                          int yytype, semantic_type& yyvalue, location_type& yylocation)

   {
   {

-    YYUSE (yylocationp);

     YYUSE (yymsg);
     YYUSE (yymsg);

-    YYUSE (yyvaluep);
+    YYUSE (yyvalue);
+    YYUSE (yylocation);

 
 

-    YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);
+    YY_SYMBOL_PRINT (yymsg, yytype, yyvalue, yylocation);

 
     switch (yytype)
       {
 
     switch (yytype)
       {


@@ -483,6 +628,15 @@ do {                                       \
       }
   }
 
       }
   }
 

+  void
+  ]b4_parser_class_name[::yypush_ (state_type s,
+                           semantic_type& v, const location_type& l)
+  {
+    yystate_stack_.push (s);
+    yysemantic_stack_.push (v);
+    yylocation_stack_.push (l);
+  }
+

   void
   ]b4_parser_class_name[::yypop_ (unsigned int n)
   {
   void
   ]b4_parser_class_name[::yypop_ (unsigned int n)
   {


@@ -565,12 +719,12 @@ m4_popdef([b4_at_dollar])])dnl
     yystate_stack_ = state_stack_type (0);
     yysemantic_stack_ = semantic_stack_type (0);
     yylocation_stack_ = location_stack_type (0);
     yystate_stack_ = state_stack_type (0);
     yysemantic_stack_ = semantic_stack_type (0);
     yylocation_stack_ = location_stack_type (0);

-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yylloc);
+    yypush_ (yystate, yylval, yylloc);

 
 

-    /* New state.  */
+    // A new state was pushed on the stack.
+    // Invariant: yystate == yystack_[0].state, i.e.,
+    // yystate was just pushed onto the state stack.

   yynewstate:
   yynewstate:

-    yystate_stack_.push (yystate);

     YYCDEBUG << "Entering state " << yystate << std::endl;
 
     /* Accept?  */
     YYCDEBUG << "Entering state " << yystate << std::endl;
 
     /* Accept?  */


@@ -607,7 +761,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     else
       {
        yytoken = yytranslate_ (yychar);
     else
       {
        yytoken = yytranslate_ (yychar);

-       YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
+       YY_SYMBOL_PRINT ("Next token is", yytoken, yylval, yylloc);

       }
 
     /* If the proper action on seeing token YYTOKEN is to reduce or to
       }
 
     /* If the proper action on seeing token YYTOKEN is to reduce or to


@@ -627,20 +781,18 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       }
 
     /* Shift the lookahead token.  */
       }
 
     /* Shift the lookahead token.  */

-    YY_SYMBOL_PRINT ("Shifting", yytoken, &yylval, &yylloc);
+    YY_SYMBOL_PRINT ("Shifting", yytoken, yylval, yylloc);

 
     /* Discard the token being shifted.  */
     yychar = yyempty_;
 
 
     /* Discard the token being shifted.  */
     yychar = yyempty_;
 

-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yylloc);
-

     /* Count tokens shifted since error; after three, turn off error
        status.  */
     if (yyerrstatus_)
       --yyerrstatus_;
 
     yystate = yyn;
     /* Count tokens shifted since error; after three, turn off error
        status.  */
     if (yyerrstatus_)
       --yyerrstatus_;
 
     yystate = yyn;

+    yypush_ (yystate, yylval, yylloc);

     goto yynewstate;
 
   /*-----------------------------------------------------------.
     goto yynewstate;
 
   /*-----------------------------------------------------------.


@@ -656,7 +808,11 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
   | yyreduce -- Do a reduction.  |
   `-----------------------------*/
   yyreduce:
   | yyreduce -- Do a reduction.  |
   `-----------------------------*/
   yyreduce:

-    yylen = yyr2_[yyn];
+    yylen = yyr2_[yyn];]b4_variant_if([
+    /* Variants are always initialized to an empty instance of the
+       correct type. The default $$=$1 rule is NOT applied when using
+       variants */
+    ]b4_symbol_variant([[yyr1_@{yyn@}]], [yyval], [build])[],[

     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 
     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 


@@ -666,7 +822,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     if (yylen)
       yyval = yysemantic_stack_@{yylen - 1@};
     else
     if (yylen)
       yyval = yysemantic_stack_@{yylen - 1@};
     else

-      yyval = yysemantic_stack_@{0@};
+      yyval = yysemantic_stack_@{0@};])[

 
     {
       slice<location_type, location_stack_type> slice (yylocation_stack_, yylen);
 
     {
       slice<location_type, location_stack_type> slice (yylocation_stack_, yylen);


@@ -679,15 +835,12 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
        default:
           break;
       }
        default:
           break;
       }

-    YY_SYMBOL_PRINT ("-> $$ =", yyr1_[yyn], &yyval, &yyloc);
+    YY_SYMBOL_PRINT ("-> $$ =", yyr1_[yyn], yyval, yyloc);

 
     yypop_ (yylen);
     yylen = 0;
     YY_STACK_PRINT ();
 
 
     yypop_ (yylen);
     yylen = 0;
     YY_STACK_PRINT ();
 

-    yysemantic_stack_.push (yyval);
-    yylocation_stack_.push (yyloc);
-

     /* Shift the result of the reduction.  */
     yyn = yyr1_[yyn];
     yystate = yypgoto_[yyn - yyntokens_] + yystate_stack_[0];
     /* Shift the result of the reduction.  */
     yyn = yyr1_[yyn];
     yystate = yypgoto_[yyn - yyntokens_] + yystate_stack_[0];


@@ -696,6 +849,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       yystate = yytable_[yystate];
     else
       yystate = yydefgoto_[yyn - yyntokens_];
       yystate = yytable_[yystate];
     else
       yystate = yydefgoto_[yyn - yyntokens_];

+    yypush_ (yystate, yyval, yyloc);

     goto yynewstate;
 
   /*------------------------------------.
     goto yynewstate;
 
   /*------------------------------------.


@@ -724,7 +878,7 @@ b4_error_verbose_if([, yytoken])[));
          }
        else
          {
          }
        else
          {

-           yydestruct_ ("Error: discarding", yytoken, &yylval, &yylloc);
+           yydestruct_ ("Error: discarding", yytoken, yylval, yylloc);

            yychar = yyempty_;
          }
       }
            yychar = yyempty_;
          }
       }


@@ -774,13 +928,13 @@ b4_error_verbose_if([, yytoken])[));
        }
 
        /* Pop the current state because it cannot handle the error token.  */
        }
 
        /* Pop the current state because it cannot handle the error token.  */

-       if (yystate_stack_.height () == 1)
+       if (yystate_stack_.size () == 1)

        YYABORT;
 
        yyerror_range[0] = yylocation_stack_[0];
        yydestruct_ ("Error: popping",
                     yystos_[yystate],
        YYABORT;
 
        yyerror_range[0] = yylocation_stack_[0];
        yydestruct_ ("Error: popping",
                     yystos_[yystate],

-                    &yysemantic_stack_[0], &yylocation_stack_[0]);
+                    yysemantic_stack_[0], yylocation_stack_[0]);

        yypop_ ();
        yystate = yystate_stack_[0];
        YY_STACK_PRINT ();
        yypop_ ();
        yystate = yystate_stack_[0];
        YY_STACK_PRINT ();


@@ -790,14 +944,13 @@ b4_error_verbose_if([, yytoken])[));
     // Using YYLLOC is tempting, but would change the location of
     // the lookahead.  YYLOC is available though.
     YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);
     // Using YYLLOC is tempting, but would change the location of
     // the lookahead.  YYLOC is available though.
     YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);

-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yyloc);

 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],
 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],

-                    &yysemantic_stack_[0], &yylocation_stack_[0]);
+                    yysemantic_stack_[0], yylocation_stack_[0]);

 
     yystate = yyn;
 
     yystate = yyn;

+    yypush_ (yystate, yylval, yyloc);

     goto yynewstate;
 
     /* Accept.  */
     goto yynewstate;
 
     /* Accept.  */


@@ -812,17 +965,17 @@ b4_error_verbose_if([, yytoken])[));
 
   yyreturn:
     if (yychar != yyempty_)
 
   yyreturn:
     if (yychar != yyempty_)

-      yydestruct_ ("Cleanup: discarding lookahead", yytoken, &yylval, &yylloc);
+      yydestruct_ ("Cleanup: discarding lookahead", yytoken, yylval, yylloc);

 
     /* Do not reclaim the symbols of the rule which action triggered
        this YYABORT or YYACCEPT.  */
     yypop_ (yylen);
 
     /* Do not reclaim the symbols of the rule which action triggered
        this YYABORT or YYACCEPT.  */
     yypop_ (yylen);

-    while (yystate_stack_.height () != 1)
+    while (yystate_stack_.size () != 1)

       {
        yydestruct_ ("Cleanup: popping",
       {
        yydestruct_ ("Cleanup: popping",

-                  yystos_[yystate_stack_[0]],
-                  &yysemantic_stack_[0],
-                  &yylocation_stack_[0]);
+                     yystos_[yystate_stack_[0]],
+                     yysemantic_stack_[0],
+                     yylocation_stack_[0]);

        yypop_ ();
       }
 
        yypop_ ();
       }
 


@@ -1018,8 +1171,8 @@ b4_error_verbose_if([, int tok])[)
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
                       yyrhs_[yyprhs_[yyrule] + yyi],
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
                       yyrhs_[yyprhs_[yyrule] + yyi],

-                      &]b4_rhs_value(yynrhs, yyi + 1)[,
-                      &]b4_rhs_location(yynrhs, yyi + 1)[);
+                      ]b4_rhs_value(yynrhs, yyi + 1)[,
+                      ]b4_rhs_location(yynrhs, yyi + 1)[);

   }
 #endif // YYDEBUG
 
   }
 #endif // YYDEBUG
 


@@ -1112,17 +1265,17 @@ b4_copyright([Stack handling for Bison parsers in C++],
     }
 
     inline
     }
 
     inline

-    unsigned int
-    height () const
+    typename S::size_type
+    size () const

     {
       return seq_.size ();
     }
 
     inline const_iterator begin () const { return seq_.rbegin (); }
     {
       return seq_.size ();
     }
 
     inline const_iterator begin () const { return seq_.rbegin (); }

-    inline const_iterator end () const { return seq_.rend (); }
+    inline const_iterator end ()   const { return seq_.rend ();   }

 
   private:
 
   private:

-
+    /// The wrapped container.

     S seq_;
   };
 
     S seq_;
   };