| 1 | //
 | 
|---|
| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
 | 
|---|
| 3 | //
 | 
|---|
| 4 | // The contents of this file are covered under the licence agreement in the
 | 
|---|
| 5 | // file "LICENCE" distributed with Cforall.
 | 
|---|
| 6 | //
 | 
|---|
| 7 | // AddressExpr.cc --
 | 
|---|
| 8 | //
 | 
|---|
| 9 | // Author           : Richard C. Bilson
 | 
|---|
| 10 | // Created On       : Sun May 17 23:54:44 2015
 | 
|---|
| 11 | // Last Modified By : Peter A. Buhr
 | 
|---|
| 12 | // Last Modified On : Thu Feb 28 13:13:38 2019
 | 
|---|
| 13 | // Update Count     : 10
 | 
|---|
| 14 | //
 | 
|---|
| 15 | 
 | 
|---|
| 16 | #include <ostream>           // for ostream, operator<<, basic_ostream, endl
 | 
|---|
| 17 | #include <string>            // for operator<<, string
 | 
|---|
| 18 | 
 | 
|---|
| 19 | #include "Common/utility.h"  // for maybeClone
 | 
|---|
| 20 | #include "Expression.h"      // for AddressExpr, Expression
 | 
|---|
| 21 | #include "Type.h"            // for PointerType, Type, Type::Qualifiers
 | 
|---|
| 22 | 
 | 
|---|
| 23 | // Address expressions are typed based on the following inference rules:
 | 
|---|
| 24 | //    E : lvalue T  &..& (n references)
 | 
|---|
| 25 | //   &E :        T *&..& (n references)
 | 
|---|
| 26 | //
 | 
|---|
| 27 | //    E : T  &..&        (m references)
 | 
|---|
| 28 | //   &E : T *&..&        (m-1 references)
 | 
|---|
| 29 | //
 | 
|---|
| 30 | // That is, lvalues becomes
 | 
|---|
| 31 | 
 | 
|---|
| 32 | namespace {
 | 
|---|
| 33 |         Type * addrType( Type * type ) {
 | 
|---|
| 34 |                 if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( type ) ) {
 | 
|---|
| 35 |                         return new ReferenceType( refType->get_qualifiers(), addrType( refType->base ) );
 | 
|---|
| 36 |                 } else {
 | 
|---|
| 37 |                         return new PointerType( Type::Qualifiers(), type->clone() );
 | 
|---|
| 38 |                 }
 | 
|---|
| 39 |         }
 | 
|---|
| 40 | }
 | 
|---|
| 41 | 
 | 
|---|
| 42 | AddressExpr::AddressExpr( Expression *arg ) : Expression(), arg( arg ) {
 | 
|---|
| 43 |         if ( arg->result ) {
 | 
|---|
| 44 |                 if ( arg->get_lvalue() ) {
 | 
|---|
| 45 |                         // lvalue, retains all layers of reference and gains a pointer inside the references
 | 
|---|
| 46 |                         set_result( addrType( arg->result ) );
 | 
|---|
| 47 |                 } else {
 | 
|---|
| 48 |                         // taking address of non-lvalue -- must be a reference, loses one layer of reference
 | 
|---|
| 49 |                         if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( arg->result ) ) {
 | 
|---|
| 50 |                                 set_result( addrType( refType->base ) );
 | 
|---|
| 51 |                         } else {
 | 
|---|
| 52 |                                 if(!arg->result->location.isSet()) arg->result->location = arg->location;
 | 
|---|
| 53 |                                 SemanticError( arg->result, "Attempt to take address of non-lvalue expression: " );
 | 
|---|
| 54 |                         } // if
 | 
|---|
| 55 |                 }
 | 
|---|
| 56 |         }
 | 
|---|
| 57 | }
 | 
|---|
| 58 | 
 | 
|---|
| 59 | AddressExpr::AddressExpr( const AddressExpr &other ) : Expression( other ), arg( maybeClone( other.arg ) ) {
 | 
|---|
| 60 | }
 | 
|---|
| 61 | 
 | 
|---|
| 62 | AddressExpr::~AddressExpr() {
 | 
|---|
| 63 |         delete arg;
 | 
|---|
| 64 | }
 | 
|---|
| 65 | 
 | 
|---|
| 66 | void AddressExpr::print( std::ostream &os, Indenter indent ) const {
 | 
|---|
| 67 |         os << "Address of:" << std::endl;
 | 
|---|
| 68 |         if ( arg ) {
 | 
|---|
| 69 |                 os << indent+1;
 | 
|---|
| 70 |                 arg->print( os, indent+1 );
 | 
|---|
| 71 |         } // if
 | 
|---|
| 72 | }
 | 
|---|
| 73 | 
 | 
|---|
| 74 | LabelAddressExpr::LabelAddressExpr( const Label &arg ) : arg( arg ) {
 | 
|---|
| 75 |         // label address always has type void *
 | 
|---|
| 76 |         result = new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) );
 | 
|---|
| 77 | }
 | 
|---|
| 78 | LabelAddressExpr::LabelAddressExpr( const LabelAddressExpr & other ) : Expression( other ), arg( other.arg ) {}
 | 
|---|
| 79 | LabelAddressExpr::~LabelAddressExpr() {}
 | 
|---|
| 80 | 
 | 
|---|
| 81 | void LabelAddressExpr::print( std::ostream & os, Indenter ) const {
 | 
|---|
| 82 |         os << "Address of label:" << arg;
 | 
|---|
| 83 | }
 | 
|---|
| 84 | 
 | 
|---|
| 85 | // Local Variables: //
 | 
|---|
| 86 | // tab-width: 4 //
 | 
|---|
| 87 | // mode: c++ //
 | 
|---|
| 88 | // compile-command: "make install" //
 | 
|---|
| 89 | // End: //
 | 
|---|