Changeset 3d26610

Timestamp:

May 31, 2018, 4:05:01 PM (7 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, with_gc

Children:

b368dd8

Parents:

bd946e4

Message:

more push/pop updates

Location:

src

Files:

• Parser/TypedefTable.cc (modified) (5 diffs)
• Parser/TypedefTable.h (modified) (2 diffs)
• Parser/parser.yy (modified) (6 diffs)
• main.cc (modified) (2 diffs)

src/Parser/TypedefTable.cc

@@ -10 +10 @@
 // Created On       : Sat May 16 15:20:13 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Tue May 22 08:40:01 2018
-// Update Count     : 121
+// Last Modified On : Wed May 30 18:04:38 2018
+// Update Count     : 148
 //
 
@@ -20 +20 @@
 #if 0
 #include <iostream>
-#define debugPrint( x ) cerr << x
+#define debugPrint( code ) code
 #else
-#define debugPrint( x )
+#define debugPrint( code )
 #endif
 
@@ -29 +29 @@
 TypedefTable::~TypedefTable() {
         if ( ! SemanticErrorThrow && kindTable.currentScope() != 0 ) {
-                // std::cerr << "scope failure " << kindTable.currentScope() << endl;
+                std::cerr << "scope failure " << kindTable.currentScope() << endl;
         } // if
 } // TypedefTable::~TypedefTable
@@ -54 +54 @@
 void TypedefTable::makeTypedef( const string & name ) {
         if ( ! typedefTable.exists( name ) ) {
-                typedefTable.addToEnclosingScope( name, TYPEDEFname );
+                typedefTable.addToEnclosingScope( name, TYPEDEFname /*, "MTD"*/ );
         } // if
 } // TypedefTable::makeTypedef
 
-void TypedefTable::addToEnclosingScope( const std::string & identifier, int kind ) {
+void TypedefTable::addToScope( const std::string & identifier, int kind /*, const char * locn*/ ) {
+        auto scope = kindTable.currentScope();
+        debugPrint( cerr << "Adding at " /* << locn */ << " " << identifier << " as kind " << kind << " scope " << scope << endl );
+        auto ret = kindTable.insertAt( scope, identifier, kind );
+        if ( ! ret.second ) ret.first->second = kind;           // exists => update
+} // TypedefTable::addToScope
+
+void TypedefTable::addToEnclosingScope( const std::string & identifier, int kind /*, const char * locn*/ ) {
         assert( kindTable.currentScope() >= 1 );
         auto scope = kindTable.currentScope() - 1;
-        debugPrint( "Adding " << identifier << " as kind " << kind << " scope " << scope << endl );
+        debugPrint( cerr << "Adding2 at " /* << locn */ << " " << identifier << " as kind " << kind << " scope " << scope << endl );
         auto ret = kindTable.insertAt( scope, identifier, kind );
         if ( ! ret.second ) ret.first->second = kind;           // exists => update
@@ -68 +75 @@
 void TypedefTable::enterScope() {
         kindTable.beginScope();
-        debugPrint( "Entering scope " << kindTable.currentScope() << endl );
+        debugPrint( cerr << "Entering scope " << kindTable.currentScope() << endl );
+        debugPrint( print() );
 } // TypedefTable::enterScope
 
 void TypedefTable::leaveScope() {
-        debugPrint( "Leaving scope " << kindTable.currentScope() << endl );
+        debugPrint( cerr << "Leaving scope " << kindTable.currentScope() << endl );
+        debugPrint( print() );
         kindTable.endScope();
 } // TypedefTable::leaveScope
 
-// void TypedefTable::print( void ) const {
-//      for ( KindTable::const_iterator i = table.begin(); i != table.end(); i++) {
-//              debugPrint( (*i ).first << ": " );
-//              list< Entry > declList = (*i).second;
-//              for ( list< Entry >::const_iterator j = declList.begin(); j != declList.end(); j++ ) {
-//                      debugPrint( "(" << (*j).scope << " " << (*j).kind << ") " );
-//              }
-//              debugPrint( endl );
-//      } // for
-// }
+void TypedefTable::print( void ) const {
+        KindTable::size_type scope = kindTable.currentScope();
+        debugPrint( cerr << "[" << scope << "]" );
+        for ( KindTable::const_iterator i = kindTable.begin(); i != kindTable.end(); i++ ) {
+                while ( i.get_level() != scope ) {
+                        --scope;
+                        debugPrint( cerr << endl << "[" << scope << "]" );
+                } // while
+                debugPrint( cerr << " " << (*i).first << ":" << (*i).second );
+        } // for
+        while ( scope > 0 ) {
+                --scope;
+                debugPrint( cerr << endl << "[" << scope << "]" );
+        }
+        debugPrint( cerr << endl );
+}
 
 // Local Variables: //

src/Parser/TypedefTable.h

@@ -10 +10 @@
 // Created On       : Sat May 16 15:24:36 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Tue May 22 08:39:29 2018
-// Update Count     : 77
+// Last Modified On : Wed May 30 17:02:49 2018
+// Update Count     : 82
 //
 
@@ -32 +32 @@
         void changeKind( const std::string & identifier, int kind );
         void makeTypedef( const std::string & name );
-        void addToEnclosingScope( const std::string & identifier, int kind );
+        void addToScope( const std::string & identifier, int kind /*, const char **/ );
+        void addToEnclosingScope( const std::string & identifier, int kind /*, const char */ );
 
         void enterScope();
         void leaveScope();
+
+        void print( void ) const;
 }; // TypedefTable
 

src/Parser/parser.yy

@@ -10 +10 @@
 // Created On       : Sat Sep  1 20:22:55 2001
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Wed May 30 20:29:03 2018
-// Update Count     : 3432
+// Last Modified On : Thu May 31 15:11:40 2018
+// Update Count     : 3444
 //
 
@@ -265 +265 @@
 %type<sn> statement                                             labeled_statement                       compound_statement
 %type<sn> statement_decl                                statement_decl_list                     statement_list_nodecl
-%type<sn> selection_statement
+%type<sn> selection_statement                   if_statement
 %type<sn> switch_clause_list_opt                switch_clause_list
 %type<en> case_value
@@ -404 +404 @@
 //************************* Namespace Management ********************************
 
-// The grammar in the ANSI C standard is not strictly context-free, since it relies upon the distinct terminal symbols
-// "identifier", "TYPEDEFname", and "TYPEGENname" that are lexically identical.  While it is possible to write a purely
-// context-free grammar, such a grammar would obscure the relationship between syntactic and semantic constructs.
-// Hence, this grammar uses the ANSI style.
-//
-// Cforall compounds this problem by introducing type names local to the scope of a declaration (for instance, those
-// introduced through "forall" qualifiers), and by introducing "type generators" -- parameterized types.  This latter
-// type name creates a third class of identifiers that must be distinguished by the scanner.
-//
-// Since the scanner cannot distinguish among the different classes of identifiers without some context information, it
-// accesses a data structure (TypedefTable) to allow classification of an identifier that it has just read.  Semantic
-// actions during the parser update this data structure when the class of identifiers change.
-//
-// Because the Cforall language is block-scoped, an identifier can change its class in a local scope; it must revert to
-// its original class at the end of the block.  Since type names can be local to a particular declaration, each
-// declaration is itself a scope.  This requires distinguishing between type names that are local to the current
-// declaration scope and those that persist past the end of the declaration (i.e., names defined in "typedef" or "otype"
-// declarations).
-//
-// The non-terminals "push" and "pop" denote the opening and closing of scopes.  Every push must have a matching pop,
-// although it is regrettable the matching pairs do not always occur within the same rule.  These non-terminals may
-// appear in more contexts than strictly necessary from a semantic point of view.
+// The C grammar is not context free because it relies on the distinct terminal symbols "identifier" and "TYPEDEFname",
+// which are lexically identical.
+//
+//   typedef int foo; // identifier foo must now be scanned as TYPEDEFname
+//   foo f;           // to allow it to appear in this context
+//
+// While it may be possible to write a purely context-free grammar, such a grammar would obscure the relationship
+// between syntactic and semantic constructs.  Cforall compounds this problem by introducing type names local to the
+// scope of a declaration (for instance, those introduced through "forall" qualifiers), and by introducing "type
+// generators" -- parameterized types.  This latter type name creates a third class of identifiers, "TYPEGENname", which
+// must be distinguished by the lexical scanner.
+//
+// Since the scanner cannot distinguish among the different classes of identifiers without some context information,
+// there is a type table (typedefTable), which holds type names and identifiers that override type names, for each named
+// scope. During parsing, semantic actions update the type table by adding new identifiers in the current scope. For
+// each context that introduces a name scope, a new level is created in the type table and that level is popped on
+// exiting the scope.  Since type names can be local to a particular declaration, each declaration is itself a scope.
+// This requires distinguishing between type names that are local to the current declaration scope and those that
+// persist past the end of the declaration (i.e., names defined in "typedef" or "otype" declarations).
+//
+// The non-terminals "push" and "pop" denote the opening and closing of named scopes. Every push has a matching pop in
+// the production rule. There are multiple lists of declarations, where each declaration is a named scope, so pop/push
+// around the list separator.
+//
+//  int f( forall(T) T (*f1) T , forall( S ) S (*f2)( S ) );
+//      push               pop   push                   pop
 
 push:
@@ -952 +956 @@
 
 selection_statement:
-        IF '(' push if_control_expression ')' statement pop             %prec THEN
-                // explicitly deal with the shift/reduce conflict on if/else
-                { $$ = new StatementNode( build_if( $4, $6, nullptr ) ); }
-        | IF '(' push if_control_expression ')' statement ELSE statement pop
-                { $$ = new StatementNode( build_if( $4, $6, $8 ) ); }
+                        // pop causes a S/R conflict without separating the IF statement into a non-terminal even after resolving
+                        // the inherent S/R conflict with THEN/ELSE.
+        push if_statement pop
+                { $$ = $2; }
         | SWITCH '(' comma_expression ')' case_clause
                 { $$ = new StatementNode( build_switch( true, $3, $5 ) ); }
@@ -977 +980 @@
                 }
         ;
+
+if_statement:
+        IF '(' if_control_expression ')' statement                      %prec THEN
+                // explicitly deal with the shift/reduce conflict on if/else
+                { $$ = new StatementNode( build_if( $3, $5, nullptr ) ); }
+        | IF '(' if_control_expression ')' statement ELSE statement
+                { $$ = new StatementNode( build_if( $3, $5, $7 ) ); }
+        ;
+
 
 if_control_expression:
@@ -1172 +1184 @@
 
 handler_clause:
-        handler_key '(' push push exception_declaration pop handler_predicate_opt ')' compound_statement pop
-                { $$ = new StatementNode( build_catch( $1, $5, $7, $9 ) ); }
-        | handler_clause handler_key '(' push push exception_declaration pop handler_predicate_opt ')' compound_statement pop
-                { $$ = (StatementNode *)$1->set_last( new StatementNode( build_catch( $2, $6, $8, $10 ) ) ); }
+        handler_key '(' push exception_declaration pop handler_predicate_opt ')' compound_statement pop
+                { $$ = new StatementNode( build_catch( $1, $4, $6, $8 ) ); }
+        | handler_clause handler_key '(' push exception_declaration pop handler_predicate_opt ')' compound_statement pop
+                { $$ = (StatementNode *)$1->set_last( new StatementNode( build_catch( $2, $5, $7, $9 ) ) ); }
         ;
 

src/main.cc

@@ -10 +10 @@
 // Created On       : Fri May 15 23:12:02 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Mon May  7 14:35:57 2018
-// Update Count     : 492
+// Last Modified On : Wed May 30 17:53:14 2018
+// Update Count     : 496
 //
 
@@ -573 +573 @@
         yyin = input;
         yylineno = 1;
-        typedefTable.enterScope();
         int parseStatus = yyparse();