Changeset a025ea8

Timestamp:

Oct 24, 2020, 9:40:24 AM (4 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

76d73fc

Parents:

9b0c3ec5

Message:

add maybe_build_compound to always build a compound statement for control structures with a single statement

Location:

src/Parser

Files:

• ParseNode.h (modified) (6 diffs)
• StatementNode.cc (modified) (2 diffs)
• parser.yy (modified) (5 diffs)

src/Parser/ParseNode.h

@@ -10 +10 @@
 // Created On       : Sat May 16 13:28:16 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Mon Jul  6 09:33:32 2020
-// Update Count     : 892
+// Last Modified On : Sat Oct 24 03:53:54 2020
+// Update Count     : 895
 //
 
@@ -205 +205 @@
 struct TypeData;
 
-class DeclarationNode : public ParseNode {
-  public:
+struct DeclarationNode : public ParseNode {
         // These enumerations must harmonize with their names in DeclarationNode.cc.
         enum BasicType { Void, Bool, Char, Int, Int128,
@@ -304 +303 @@
         bool get_inLine() const { return inLine; }
         DeclarationNode * set_inLine( bool inL ) { inLine = inL; return this; }
-  public:
+
         DeclarationNode * get_last() { return (DeclarationNode *)ParseNode::get_last(); }
 
@@ -360 +359 @@
 //##############################################################################
 
-class StatementNode final : public ParseNode {
-  public:
+struct StatementNode final : public ParseNode {
         StatementNode() { stmt = nullptr; }
         StatementNode( Statement * stmt ) : stmt( stmt ) {}
@@ -382 +380 @@
                 os << stmt.get() << std::endl;
         }
-  private:
+
         std::unique_ptr<Statement> stmt;
 }; // StatementNode
@@ -426 +424 @@
 Statement * build_finally( StatementNode * stmt );
 Statement * build_compound( StatementNode * first );
+StatementNode * maybe_build_compound( StatementNode * first );
 Statement * build_asm( bool voltile, Expression * instruction, ExpressionNode * output = nullptr, ExpressionNode * input = nullptr, ExpressionNode * clobber = nullptr, LabelNode * gotolabels = nullptr );
 Statement * build_directive( std::string * directive );

src/Parser/StatementNode.cc

@@ -10 +10 @@
 // Created On       : Sat May 16 14:59:41 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Sat Aug  4 09:39:25 2018
-// Update Count     : 363
+// Last Modified On : Sat Oct 24 04:20:55 2020
+// Update Count     : 383
 //
 
@@ -345 +345 @@
 } // build_compound
 
+// A single statement in a control structure is always converted to a compound statement so subsequent generated code
+// can be placed within this compound statement. Otherwise, code generation has to constantly check for a single
+// statement and wrap it into a compound statement to insert additional code. Hence, all control structures have a
+// conical form for code generation.
+StatementNode * maybe_build_compound( StatementNode * first ) {
+        // Optimization: if the control-structure statement is a compound statement, do not wrap it.
+        // e.g., if (...) {...} do not wrap the existing compound statement.
+        if ( ! dynamic_cast<CompoundStmt *>( first->stmt.get() ) ) { // unique_ptr
+                CompoundStmt * cs = new CompoundStmt();
+                buildMoveList( first, cs->get_kids() );
+                return new StatementNode( cs );
+        } // if
+        return first;
+} // maybe_build_compound
+
 Statement * build_asm( bool voltile, Expression * instruction, ExpressionNode * output, ExpressionNode * input, ExpressionNode * clobber, LabelNode * gotolabels ) {
         std::list< Expression * > out, in;

src/Parser/parser.yy

@@ -10 +10 @@
 // Created On       : Sat Sep  1 20:22:55 2001
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Fri Oct  9 18:09:09 2020
-// Update Count     : 4614
+// Last Modified On : Sat Oct 24 08:21:14 2020
+// Update Count     : 4624
 //
 
@@ -1080 +1080 @@
         IF '(' if_control_expression ')' statement                      %prec THEN
                 // explicitly deal with the shift/reduce conflict on if/else
-                { $$ = new StatementNode( build_if( $3, $5, nullptr ) ); }
+                { $$ = new StatementNode( build_if( $3, maybe_build_compound( $5 ), nullptr ) ); }
         | IF '(' if_control_expression ')' statement ELSE statement
-                { $$ = new StatementNode( build_if( $3, $5, $7 ) ); }
+                { $$ = new StatementNode( build_if( $3, maybe_build_compound( $5 ), maybe_build_compound( $7 ) ) ); }
         ;
 
@@ -1130 +1130 @@
 
 case_clause:                                                                                    // CFA
-        case_label_list statement                                       { $$ = $1->append_last_case( new StatementNode( build_compound( $2 ) ) ); }
+        case_label_list statement                                       { $$ = $1->append_last_case( maybe_build_compound( $2 ) ); }
         ;
 
@@ -1148 +1148 @@
 iteration_statement:
         WHILE '(' push if_control_expression ')' statement pop
-                { $$ = new StatementNode( build_while( $4, $6 ) ); }
+                { $$ = new StatementNode( build_while( $4, maybe_build_compound( $6 ) ) ); }
         | WHILE '(' ')' statement                                                       // CFA => while ( 1 )
-                { $$ = new StatementNode( build_while( new IfCtrl( nullptr, new ExpressionNode( build_constantInteger( *new string( "1" ) ) ) ), $4 ) ); }
+                { $$ = new StatementNode( build_while( new IfCtrl( nullptr, new ExpressionNode( build_constantInteger( *new string( "1" ) ) ) ), maybe_build_compound( $4 ) ) ); }
         | DO statement WHILE '(' comma_expression ')' ';'
-                { $$ = new StatementNode( build_do_while( $5, $2 ) ); }
+                { $$ = new StatementNode( build_do_while( $5, maybe_build_compound( $2 ) ) ); }
         | DO statement WHILE '(' ')' ';'                                        // CFA => do while( 1 )
-                { $$ = new StatementNode( build_do_while( new ExpressionNode( build_constantInteger( *new string( "1" ) ) ), $2 ) ); }
+                { $$ = new StatementNode( build_do_while( new ExpressionNode( build_constantInteger( *new string( "1" ) ) ), maybe_build_compound( $2 ) ) ); }
         | FOR '(' push for_control_expression_list ')' statement pop
-                { $$ = new StatementNode( build_for( $4, $6 ) ); }
+                { $$ = new StatementNode( build_for( $4, maybe_build_compound( $6 ) ) ); }
         | FOR '(' ')' statement                                                         // CFA => for ( ;; )
-                { $$ = new StatementNode( build_for( new ForCtrl( (ExpressionNode * )nullptr, (ExpressionNode * )nullptr, (ExpressionNode * )nullptr ), $4 ) ); }
+                { $$ = new StatementNode( build_for( new ForCtrl( (ExpressionNode * )nullptr, (ExpressionNode * )nullptr, (ExpressionNode * )nullptr ), maybe_build_compound( $4 ) ) ); }
         ;
 
@@ -1341 +1341 @@
 waitfor_clause:
         when_clause_opt waitfor statement                                       %prec THEN
-                { $$ = build_waitfor( $2, $3, $1 ); }
+                { $$ = build_waitfor( $2, maybe_build_compound( $3 ), $1 ); }
         | when_clause_opt waitfor statement WOR waitfor_clause
-                { $$ = build_waitfor( $2, $3, $1, $5 ); }
+                { $$ = build_waitfor( $2, maybe_build_compound( $3 ), $1, $5 ); }
         | when_clause_opt timeout statement                                     %prec THEN
-                { $$ = build_waitfor_timeout( $2, $3, $1 ); }
+                { $$ = build_waitfor_timeout( $2, maybe_build_compound( $3 ), $1 ); }
         | when_clause_opt ELSE statement
-                { $$ = build_waitfor_timeout( nullptr, $3, $1 ); }
+                { $$ = build_waitfor_timeout( nullptr, maybe_build_compound( $3 ), $1 ); }
                 // "else" must be conditional after timeout or timeout is never triggered (i.e., it is meaningless)
         | when_clause_opt timeout statement WOR ELSE statement
                 { SemanticError( yylloc, "else clause must be conditional after timeout or timeout never triggered." ); $$ = nullptr; }
         | when_clause_opt timeout statement WOR when_clause ELSE statement
-                { $$ = build_waitfor_timeout( $2, $3, $1, $7, $5 ); }
+                { $$ = build_waitfor_timeout( $2, maybe_build_compound( $3 ), $1, maybe_build_compound( $7 ), $5 ); }
         ;