Changeset 4e06c1e for src/Parser/parser.yy

Timestamp:

Jul 12, 2016, 6:34:10 PM (9 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

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

Children:

e4d3ceb

Parents:

6e4b913

Message:

changes for switch and choose statements

File:

• src/Parser/parser.yy (modified) (11 diffs)

src/Parser/parser.yy

@@ -10 +10 @@
 // Created On       : Sat Sep  1 20:22:55 2001
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Thu Jun 30 21:15:54 2016
-// Update Count     : 1657
+// Last Modified On : Tue Jul 12 17:26:32 2016
+// Update Count     : 1659
 //
 
@@ -712 +712 @@
                 { $$ = new StatementNode( StatementNode::Switch, $3, $5 ); }
         | SWITCH '(' comma_expression ')' '{' push declaration_list_opt switch_clause_list_opt '}' // CFA
-                { $$ = new StatementNode( StatementNode::Switch, $3, $8 ); /* xxx */ }
-                // The semantics of the declaration list is changed to include any associated initialization, which is performed
-                // *before* the transfer to the appropriate case clause.  Statements after the initial declaration list can
-                // never be executed, and therefore, are removed from the grammar even though C allows it.
+                {
+                        StatementNode *sw = new StatementNode( StatementNode::Switch, $3, $8 );
+                        // The semantics of the declaration list is changed to include associated initialization, which is performed
+                        // *before* the transfer to the appropriate case clause by hoisting the declarations into a compound
+                        // statement around the switch.  Statements after the initial declaration list can never be executed, and
+                        // therefore, are removed from the grammar even though C allows it. Change also applies to choose statement.
+                        $$ = $7 != 0 ? new CompoundStmtNode( (StatementNode *)((new StatementNode( $7 ))->set_link( sw )) ) : sw;
+                }
         | CHOOSE '(' comma_expression ')' case_clause           // CFA
-                { $$ = new StatementNode( StatementNode::Choose, $3, $5 ); }
+                { $$ = new StatementNode( StatementNode::Switch, $3, $5 ); }
         | CHOOSE '(' comma_expression ')' '{' push declaration_list_opt choose_clause_list_opt '}' // CFA
-                { $$ = new StatementNode( StatementNode::Choose, $3, $8 ); }
+                {
+                        StatementNode *sw = new StatementNode( StatementNode::Switch, $3, $8 );
+                        $$ = $7 != 0 ? new CompoundStmtNode( (StatementNode *)((new StatementNode( $7 ))->set_link( sw )) ) : sw;
+                }
         ;
 
@@ -750 +757 @@
 
 case_clause:                                                                                    // CFA
-        case_label_list statement                                       { $$ = $1->append_last_case( $2 ); }
+        case_label_list statement                                       { $$ = $1->append_last_case( new CompoundStmtNode( $2 ) ); }
         ;
 
@@ -761 +768 @@
 switch_clause_list:                                                                             // CFA
         case_label_list statement_list
-                { $$ = $1->append_last_case( $2 ); }
+                { $$ = $1->append_last_case( new CompoundStmtNode( $2 ) ); }
         | switch_clause_list case_label_list statement_list
-                { $$ = (StatementNode *)( $1->set_link( $2->append_last_case( $3 ))); }
+                { $$ = (StatementNode *)( $1->set_link( $2->append_last_case( new CompoundStmtNode( $3 ) ) ) ); }
         ;
 
@@ -776 +783 @@
                 { $$ = $1->append_last_case( $2 ); }
         | case_label_list statement_list fall_through_opt
-                { $$ = $1->append_last_case((StatementNode *)mkList((*$2,*$3 ))); }
+                { $$ = $1->append_last_case( new CompoundStmtNode( (StatementNode *)mkList( (*$2, *$3 ) ) ) ); }
         | choose_clause_list case_label_list fall_through
                 { $$ = (StatementNode *)( $1->set_link( $2->append_last_case( $3 ))); }
         | choose_clause_list case_label_list statement_list fall_through_opt
-                { $$ = (StatementNode *)( $1->set_link( $2->append_last_case((StatementNode *)mkList((*$3,*$4 ))))); }
+                { $$ = (StatementNode *)( $1->set_link( $2->append_last_case( new CompoundStmtNode( (StatementNode *)mkList( (*$3, *$4 ) ) ) ) ) ); }
         ;
 
 fall_through_opt:                                                                               // CFA
         // empty
+                { $$ = new StatementNode( StatementNode::Break ); }     // insert implicit break
+        | fall_through
+        ;
+
+fall_through:                                                                                   // CFA
+        FALLTHRU
                 { $$ = 0; }
-        | fall_through
-        ;
-
-fall_through:                                                                                   // CFA
-        FALLTHRU                                                                        { $$ = new StatementNode( StatementNode::Fallthru ); }
-        | FALLTHRU ';'                                                          { $$ = new StatementNode( StatementNode::Fallthru ); }
+        | FALLTHRU ';'
+                { $$ = 0; }
         ;
 
@@ -814 +823 @@
                 { $$ = new StatementNode( StatementNode::Goto, $2 ); }
         | GOTO '*' comma_expression ';'                                         // GCC, computed goto
-                // The syntax for the GCC computed goto violates normal expression precedence, e.g., goto *i+3; => goto *(i+3 );
+                // The syntax for the GCC computed goto violates normal expression precedence, e.g., goto *i+3; => goto *(i+3);
                 // whereas normal operator precedence yields goto (*i)+3;
                 { $$ = new StatementNode( StatementNode::Goto, $3 ); }
@@ -820 +829 @@
                 // A semantic check is required to ensure this statement appears only in the body of an iteration statement.
                 { $$ = new StatementNode( StatementNode::Continue ); }
-        | CONTINUE IDENTIFIER ';'                                       // CFA, multi-level continue
+        | CONTINUE IDENTIFIER ';'                                                       // CFA, multi-level continue
                 // A semantic check is required to ensure this statement appears only in the body of an iteration statement, and
                 // the target of the transfer appears only at the start of an iteration statement.
@@ -827 +836 @@
                 // A semantic check is required to ensure this statement appears only in the body of an iteration statement.
                 { $$ = new StatementNode( StatementNode::Break ); }
-        | BREAK IDENTIFIER ';'                                          // CFA, multi-level exit
+        | BREAK IDENTIFIER ';'                                                          // CFA, multi-level exit
                 // A semantic check is required to ensure this statement appears only in the body of an iteration statement, and
                 // the target of the transfer appears only at the start of an iteration statement.
@@ -951 +960 @@
         ;
 
-asm_clobbers_list_opt:                                                                          // GCC
+asm_clobbers_list_opt:                                                                  // GCC
         // empty
                 { $$ = 0; }                                                                             // use default argument
@@ -1452 +1461 @@
                 { typedefTable.makeTypedef( *$2 ); }
                 '{' field_declaration_list '}'
-                { $$ = DeclarationNode::newAggregate( $1, $2, 0, $5); }
+                { $$ = DeclarationNode::newAggregate( $1, $2, 0, $5 ); }
         | aggregate_key '(' type_name_list ')' '{' field_declaration_list '}' // CFA
                 { $$ = DeclarationNode::newAggregate( $1, 0, $3, $6 ); }
@@ -1840 +1849 @@
                 { $$ = 0; }
         | assertion_list_opt assertion
-                { $$ = $1 == 0 ? $2 : $1->appendList( $2 ); }
+                { $$ = $1 != 0 ? $1->appendList( $2 ) : $2; }
         ;