source: src/SynTree/AddressExpr.cc @ 8135d4c

ADTaaron-thesisarm-ehast-experimentalcleanup-dtorsdeferred_resndemanglerenumforall-pointer-decayjacob/cs343-translationjenkins-sandboxnew-astnew-ast-unique-exprnew-envno_listpersistent-indexerpthread-emulationqualifiedEnumresolv-newwith_gc
Last change on this file since 8135d4c was 8135d4c, checked in by Rob Schluntz <rschlunt@…>, 7 years ago

Merge branch 'master' into references

  • Property mode set to 100644
File size: 2.3 KB
Line 
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 : Rob Schluntz
12// Last Modified On : Tue Apr 26 12:35:13 2016
13// Update Count     : 6
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
32namespace {
33        Type * addrType( Type * type ) {
34                if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( type ) ) {
35                        return new ReferenceType( refType->get_qualifiers(), addrType( refType->get_base() ) );
36                } else {
37                        return new PointerType( Type::Qualifiers(), type->clone() );
38                }
39        }
40}
41
42AddressExpr::AddressExpr( Expression *arg, Expression *_aname ) : Expression( _aname ), arg( arg ) {
43        if ( arg->has_result() ) {
44                if ( arg->get_result()->get_lvalue() ) {
45                        // lvalue, retains all layers of reference and gains a pointer inside the references
46                        set_result( addrType( arg->get_result() ) );
47                } else {
48                        // taking address of non-lvalue -- must be a reference, loses one layer of reference
49                        ReferenceType * refType = safe_dynamic_cast< ReferenceType * >( arg->get_result() );
50                        set_result( addrType( refType->get_base() ) );
51                }
52                // result of & is never an lvalue
53                get_result()->set_lvalue( false );
54        }
55}
56
57AddressExpr::AddressExpr( const AddressExpr &other ) : Expression( other ), arg( maybeClone( other.arg ) ) {
58}
59
60AddressExpr::~AddressExpr() {
61        delete arg;
62}
63
64void AddressExpr::print( std::ostream &os, int indent ) const {
65        os << "Address of:" << std::endl;
66        if ( arg ) {
67                os << std::string( indent+2, ' ' );
68                arg->print( os, indent+2 );
69        } // if
70}
71
72// Local Variables: //
73// tab-width: 4 //
74// mode: c++ //
75// compile-command: "make install" //
76// End: //
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