Changeset 65660bd for src/Tuples/Tuples.h

Timestamp:

Sep 22, 2016, 8:14:56 AM (7 years ago)

Author:

Rob Schluntz <rschlunt@…>

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, resolv-new, with_gc

Children:

ac9ca96

Parents:

1132b62

git-author:

Rob Schluntz <rschlunt@…> (09/21/16 23:43:37)

git-committer:

Rob Schluntz <rschlunt@…> (09/22/16 08:14:56)

Message:

replace multiple-returning functions with tuple-returning functions, implement tuple ctor/dtor, allow N-arg tuple assignment

File:

• src/Tuples/Tuples.h (modified) (3 diffs)

src/Tuples/Tuples.h

@@ -15 +15 @@
 
 #ifndef _TUPLES_H_
-#define _TUPLE_H_
+#define _TUPLES_H_
 
 #include <string>
@@ -27 +27 @@
 namespace Tuples {
         // TupleAssignment.cc
-        void handleTupleAssignment( ResolvExpr::AlternativeFinder & currentFinder, UntypedExpr * assign, std::list<ResolvExpr::AltList> & possibilities );
+        void handleTupleAssignment( ResolvExpr::AlternativeFinder & currentFinder, UntypedExpr * assign, const std::list<ResolvExpr::AltList> & possibilities );
 
         // TupleExpansion.cc
@@ -34 +34 @@
   void expandUniqueExpr( std::list< Declaration * > & translationUnit );
 
-  TupleType * makeTupleType( const std::list< Expression * > & exprs );
+  /// returns VoidType if any of the expressions have Voidtype, otherwise TupleType of the Expression result types
+  Type * makeTupleType( const std::list< Expression * > & exprs );
+
+  bool maybeImpure( Expression * expr );
+
+
+        /// helper function used by explode
+        template< typename OutputIterator >
+        void explodeUnique( Expression * expr, const ResolvExpr::Alternative & alt, OutputIterator out ) {
+                Type * res = expr->get_result();
+                if ( AddressExpr * addrExpr = dynamic_cast< AddressExpr * >( expr ) ) {
+                        ResolvExpr::AltList alts;
+                        explodeUnique( addrExpr->get_arg(), alt, back_inserter( alts ) );
+                        for ( ResolvExpr::Alternative & alt : alts ) {
+                                // distribute '&' over all components
+                                alt.expr = new AddressExpr( alt.expr );
+                                *out++ = alt;
+                        }
+                } else if ( TupleType * tupleType = dynamic_cast< TupleType * > ( res ) ) {
+                        if ( TupleExpr * tupleExpr = dynamic_cast< TupleExpr * >( expr ) ) {
+                                // can open tuple expr and dump its exploded components
+                                for ( Expression * expr : tupleExpr->get_exprs() ) {
+                                        explodeUnique( expr, alt, out );
+                                }
+                        } else {
+                                // tuple type, but not tuple expr - recursively index into its components
+                                Expression * arg = expr->clone();
+                                if ( Tuples::maybeImpure( arg ) ) {
+                                        // expressions which may contain side effects require a single unique instance of the expression
+                                        arg = new UniqueExpr( arg );
+                                }
+                                for ( unsigned int i = 0; i < tupleType->size(); i++ ) {
+                                        TupleIndexExpr * idx = new TupleIndexExpr( arg->clone(), i );
+                                        explodeUnique( idx, alt, out );
+                                        delete idx;
+                                }
+                                delete arg;
+                        }
+                } else {
+                        // atomic (non-tuple) type - output a clone of the expression in a new alternative
+                        *out++ = ResolvExpr::Alternative( expr->clone(), alt.env, alt.cost, alt.cvtCost );
+                }
+        }
+
+        /// expands a tuple-valued alternative into multiple alternatives, each with a non-tuple-type
+        template< typename OutputIterator >
+        void explode( const ResolvExpr::Alternative &alt, OutputIterator out ) {
+                explodeUnique( alt.expr, alt, out );
+        }
+
+        // explode list of alternatives
+        template< typename AltIterator, typename OutputIterator >
+        void explode( AltIterator altBegin, AltIterator altEnd, OutputIterator out ) {
+                for ( ; altBegin != altEnd; ++altBegin ) {
+                        explode( *altBegin, out );
+                }
+        }
+
+        template< typename OutputIterator >
+        void explode( const ResolvExpr::AltList & alts, OutputIterator out ) {
+                explode( alts.begin(), alts.end(), out );
+        }
 } // namespace Tuples