Context Navigation

source: src/GenPoly/Lvalue.cc @ da7fe39

ADTaaron-thesisarm-ehast-experimentalcleanup-dtorsdeferred_resndemanglerenumforall-pointer-decayjacob/cs343-translationjenkins-sandboxnew-astnew-ast-unique-exprnew-envno_listpersistent-indexerpthread-emulationqualifiedEnumwith_gc

Last change on this file since da7fe39 was da7fe39, checked in by Rob Schluntz <rschlunt@…>, 6 years ago
Merge branch 'master' into references
Property mode set to `100644`
File size: 22.9 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	// Lvalue.cc --
8	//
9	// Author : Richard C. Bilson
10	// Created On : Mon May 18 07:44:20 2015
11	// Last Modified By : Peter A. Buhr
12	// Last Modified On : Fri Mar 17 09:11:18 2017
13	// Update Count : 5
14	//
15
16	#include <cassert> // for strict_dynamic_cast
17	#include <string> // for string
18
19	#include "Common/Debug.h"
20	#include "Common/PassVisitor.h"
21	#include "GenPoly.h" // for isPolyType
22	#include "Lvalue.h"
23
24	#include "Parser/LinkageSpec.h" // for Spec, isBuiltin, Intrinsic
25	#include "ResolvExpr/TypeEnvironment.h" // for AssertionSet, OpenVarSet
26	#include "ResolvExpr/Unify.h" // for unify
27	#include "ResolvExpr/typeops.h"
28	#include "SymTab/Autogen.h"
29	#include "SymTab/Indexer.h" // for Indexer
30	#include "SynTree/Declaration.h" // for Declaration, FunctionDecl
31	#include "SynTree/Expression.h" // for Expression, ConditionalExpr
32	#include "SynTree/Mutator.h" // for mutateAll, Mutator
33	#include "SynTree/Statement.h" // for ReturnStmt, Statement (ptr o...
34	#include "SynTree/Type.h" // for PointerType, Type, FunctionType
35	#include "SynTree/Visitor.h" // for Visitor, acceptAll
36
37	#if 0
38	#define PRINT(x) x
39	#else
40	#define PRINT(x)
41	#endif
42
43	namespace GenPoly {
44	namespace {
45	// TODO: fold this into the general createDeref function??
46	Expression * mkDeref( Expression * arg ) {
47	if ( SymTab::dereferenceOperator ) {
48	// note: reference depth can be arbitrarily deep here, so peel off the outermost pointer/reference, not just pointer because they are effecitvely equivalent in this pass
49	VariableExpr * deref = new VariableExpr( SymTab::dereferenceOperator );
50	deref->result = new PointerType( Type::Qualifiers(), deref->result );
51	Type * base = InitTweak::getPointerBase( arg->result );
52	assertf( base, "expected pointer type in dereference (type was %s)", toString( arg->result ).c_str() );
53	ApplicationExpr * ret = new ApplicationExpr( deref, { arg } );
54	delete ret->result;
55	ret->result = base->clone();
56	ret->result->set_lvalue( true );
57	return ret;
58	} else {
59	return UntypedExpr::createDeref( arg );
60	}
61	}
62
63	struct ReferenceConversions final : public WithStmtsToAdd {
64	Expression * postmutate( CastExpr * castExpr );
65	Expression * postmutate( AddressExpr * addrExpr );
66	};
67
68	/// Intrinsic functions that take reference parameters don't REALLY take reference parameters -- their reference arguments must always be implicitly dereferenced.
69	struct FixIntrinsicArgs final {
70	Expression * postmutate( ApplicationExpr * appExpr );
71	};
72
73	struct FixIntrinsicResult final : public WithGuards {
74	Expression * postmutate( ApplicationExpr * appExpr );
75	void premutate( FunctionDecl * funcDecl );
76	bool inIntrinsic = false;
77	};
78
79	/// Replace reference types with pointer types
80	struct ReferenceTypeElimination final {
81	Type * postmutate( ReferenceType * refType );
82	};
83
84	/// GCC-like Generalized Lvalues (which have since been removed from GCC)
85	/// https://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Lvalues.html#Lvalues
86	/// Replaces &(a,b) with (a, &b), &(a ? b : c) with (a ? &b : &c)
87	struct GeneralizedLvalue final : public WithVisitorRef<GeneralizedLvalue> {
88	Expression * postmutate( AddressExpr * addressExpr );
89	Expression * postmutate( MemberExpr * memExpr );
90
91	template<typename Func>
92	Expression * applyTransformation( Expression * expr, Expression * arg, Func mkExpr );
93	};
94
95	/// Removes redundant &/& pattern that this pass can generate
96	struct CollapseAddrDeref final {
97	Expression * postmutate( AddressExpr * addressExpr );
98	Expression * postmutate( ApplicationExpr * appExpr );
99	};
100
101	struct AddrRef final : public WithGuards, public WithVisitorRef<AddrRef>, public WithShortCircuiting {
102	void premutate( AddressExpr * addrExpr );
103	Expression * postmutate( AddressExpr * addrExpr );
104	void premutate( Expression * expr );
105	void premutate( ApplicationExpr * appExpr );
106	void premutate( SingleInit * init );
107
108	void handleNonAddr( Expression * );
109
110	bool first = true;
111	bool current = false;
112	int refDepth = 0;
113	bool addCast = false;
114	};
115	} // namespace
116
117	static bool referencesEliminated = false;
118	// used by UntypedExpr::createDeref to determine whether result type of dereference should be ReferenceType or value type.
119	bool referencesPermissable() {
120	return ! referencesEliminated;
121	}
122
123	void convertLvalue( std::list< Declaration* > & translationUnit ) {
124	PassVisitor<ReferenceConversions> refCvt;
125	PassVisitor<ReferenceTypeElimination> elim;
126	PassVisitor<GeneralizedLvalue> genLval;
127	PassVisitor<FixIntrinsicArgs> fixer;
128	PassVisitor<CollapseAddrDeref> collapser;
129	PassVisitor<AddrRef> addrRef;
130	PassVisitor<FixIntrinsicResult> intrinsicResults;
131	Debug::codeGen( translationUnit, "begin" );
132	mutateAll( translationUnit, intrinsicResults );
133	Debug::codeGen( translationUnit, "intrinsicResults" );
134	mutateAll( translationUnit, addrRef );
135	Debug::codeGen( translationUnit, "addrRef" );
136	mutateAll( translationUnit, refCvt );
137	Debug::codeGen( translationUnit, "refCvt" );
138	mutateAll( translationUnit, fixer );
139	Debug::codeGen( translationUnit, "fixer" );
140	mutateAll( translationUnit, collapser );
141	Debug::codeGen( translationUnit, "collapser" );
142	mutateAll( translationUnit, genLval );
143	Debug::codeGen( translationUnit, "genLval" );
144	mutateAll( translationUnit, elim ); // last because other passes need reference types to work
145	Debug::codeGen( translationUnit, "elim" );
146
147	// from this point forward, no other pass should create reference types.
148	referencesEliminated = true;
149	}
150
151	Expression * generalizedLvalue( Expression * expr ) {
152	PassVisitor<GeneralizedLvalue> genLval;
153	return expr->acceptMutator( genLval );
154	}
155
156	namespace {
157	// true for intrinsic function calls that return a reference
158	bool isIntrinsicReference( Expression * expr ) {
159	if ( UntypedExpr * untyped = dynamic_cast< UntypedExpr * >( expr ) ) {
160	std::string fname = InitTweak::getFunctionName( untyped );
161	// known intrinsic-reference prelude functions
162	return fname == "*?" \|\| fname == "?[?]";
163	} else if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * > ( expr ) ) {
164	if ( DeclarationWithType * func = InitTweak::getFunction( appExpr ) ) {
165	// use type of return variable rather than expr result type, since it may have been changed to a pointer type
166	FunctionType * ftype = GenPoly::getFunctionType( func->get_type() );
167	Type * ret = ftype->returnVals.empty() ? nullptr : ftype->returnVals.front()->get_type();
168	return func->linkage == LinkageSpec::Intrinsic && dynamic_cast<ReferenceType *>( ret );
169	}
170	}
171	return false;
172	}
173
174	Expression * FixIntrinsicResult::postmutate( ApplicationExpr * appExpr ) {
175	if ( isIntrinsicReference( appExpr ) ) {
176	// eliminate reference types from intrinsic applications - now they return lvalues
177	Type * result = appExpr->result;
178	appExpr->result = result->stripReferences()->clone();
179	appExpr->result->set_lvalue( true );
180	if ( ! inIntrinsic ) {
181	// when not in an intrinsic function, add a cast to
182	// don't add cast when in an intrinsic function, since they already have the cast
183	Expression * ret = new CastExpr( appExpr, result );
184	std::swap( ret->env, appExpr->env );
185	return ret;
186	}
187	delete result;
188	}
189	return appExpr;
190	}
191
192	void FixIntrinsicResult::premutate( FunctionDecl * funcDecl ) {
193	GuardValue( inIntrinsic );
194	inIntrinsic = funcDecl->linkage == LinkageSpec::Intrinsic;
195	}
196
197	Expression * FixIntrinsicArgs::postmutate( ApplicationExpr * appExpr ) {
198	// intrinsic functions don't really take reference-typed parameters, so they require an implicit dereference on their arguments.
199	if ( DeclarationWithType * function = InitTweak::getFunction( appExpr ) ) {
200	FunctionType * ftype = GenPoly::getFunctionType( function->get_type() );
201	assertf( ftype, "Function declaration does not have function type." );
202	// can be of differing lengths only when function is variadic
203	assertf( ftype->parameters.size() == appExpr->args.size() \|\| ftype->isVarArgs, "ApplicationExpr args do not match formal parameter type." );
204
205
206	unsigned int i = 0;
207	const unsigned int end = ftype->parameters.size();
208	for ( auto p : unsafe_group_iterate( appExpr->args, ftype->parameters ) ) {
209	if (i == end) break;
210	Expression *& arg = std::get<0>( p );
211	Type * formal = std::get<1>( p )->get_type();
212	PRINT(
213	std::cerr << "pair<0>: " << arg << std::endl;
214	std::cerr << " -- " << arg->result << std::endl;
215	std::cerr << "pair<1>: " << formal << std::endl;
216	)
217	if ( dynamic_cast<ReferenceType*>( formal ) ) {
218	PRINT(
219	std::cerr << "===formal is reference" << std::endl;
220	)
221	// TODO: it's likely that the second condition should be ... && ! isIntrinsicReference( arg ), but this requires investigation.
222
223	if ( function->get_linkage() != LinkageSpec::Intrinsic && isIntrinsicReference( arg ) ) {
224	// needed for definition of prelude functions, etc.
225	// if argument is dereference or array subscript, the result isn't REALLY a reference, but non-intrinsic functions expect a reference: take address
226
227	// NOTE: previously, this condition fixed
228	// void f(int *&);
229	// int & x = ...;
230	// f(&x);
231	// But now this is taken care of by a reference cast added by AddrRef. Need to find a new
232	// example or remove this branch.
233
234	PRINT(
235	std::cerr << "===is intrinsic arg in non-intrinsic call - adding address" << std::endl;
236	)
237	arg = new AddressExpr( arg );
238	// } else if ( function->get_linkage() == LinkageSpec::Intrinsic && InitTweak::getPointerBase( arg->result ) ) {
239	} else if ( function->get_linkage() == LinkageSpec::Intrinsic && arg->result->referenceDepth() != 0 ) {
240	// argument is a 'real' reference, but function expects a C lvalue: add a dereference to the reference-typed argument
241	PRINT(
242	std::cerr << "===is non-intrinsic arg in intrinsic call - adding deref to arg" << std::endl;
243	)
244	Type * baseType = InitTweak::getPointerBase( arg->result );
245	assertf( baseType, "parameter is reference, arg must be pointer or reference: %s", toString( arg->result ).c_str() );
246	PointerType * ptrType = new PointerType( Type::Qualifiers(), baseType->clone() );
247	delete arg->result;
248	arg->result = ptrType;
249	arg = mkDeref( arg );
250	// assertf( arg->result->referenceDepth() == 0, "Reference types should have been eliminated from intrinsic function calls, but weren't: %s", toCString( arg->result ) );
251	}
252	}
253	++i;
254	}
255	}
256	return appExpr;
257	}
258
259	// idea: &&&E: get outer &, inner &
260	// at inner &, record depth D of reference type of argument of &
261	// at outer &, add D derefs.
262	void AddrRef::handleNonAddr( Expression * ) {
263	// non-address-of: reset status variables:
264	// * current expr is NOT the first address-of expr in an address-of chain
265	// * next seen address-of expr IS the first in the chain.
266	GuardValue( current );
267	GuardValue( first );
268	current = false;
269	first = true;
270	}
271
272	void AddrRef::premutate( Expression * expr ) {
273	handleNonAddr( expr );
274	GuardValue( addCast );
275	addCast = false;
276	}
277
278	void AddrRef::premutate( AddressExpr * ) {
279	GuardValue( current );
280	GuardValue( first );
281	current = first; // is this the first address-of in the chain?
282	first = false; // from here out, no longer possible for next address-of to be first in chain
283	if ( current ) { // this is the outermost address-of in a chain
284	GuardValue( refDepth );
285	refDepth = 0; // set depth to 0 so that postmutate can find the innermost address-of easily
286	}
287	}
288
289	Expression * AddrRef::postmutate( AddressExpr * addrExpr ) {
290	PRINT( std::cerr << "addr ref at " << addrExpr << std::endl; )
291	if ( refDepth == 0 ) {
292	PRINT( std::cerr << "depth 0, get new depth..." << std::endl; )
293	// this is the innermost address-of in a chain, record depth D
294	if ( ! isIntrinsicReference( addrExpr->arg ) ) {
295	// try to avoid ?[?]
296	// xxx - is this condition still necessary? intrinsicReferences should have a cast around them at this point, so I don't think this condition ever fires.
297	refDepth = addrExpr->arg->result->referenceDepth();
298	PRINT( std::cerr << "arg not intrinsic reference, new depth is: " << refDepth << std::endl; )
299	} else {
300	assertf( false, "AddrRef : address-of should not have intrinsic reference argument: %s", toCString( addrExpr->arg ) );
301	}
302	}
303	if ( current ) { // this is the outermost address-of in a chain
304	PRINT( std::cerr << "current, depth is: " << refDepth << std::endl; )
305	Expression * ret = addrExpr;
306	while ( refDepth ) {
307	// add one dereference for each
308	ret = mkDeref( ret );
309	refDepth--;
310	}
311
312	if ( addCast ) {
313	PRINT( std::cerr << "adding cast..." << std::endl; )
314	return new CastExpr( ret, addrExpr->result->clone() );
315	}
316	return ret;
317	}
318	PRINT( std::cerr << "not current..." << std::endl; )
319	return addrExpr;
320	}
321
322	void AddrRef::premutate( ApplicationExpr * appExpr ) {
323	visit_children = false;
324	GuardValue( addCast );
325	handleNonAddr( appExpr );
326	for ( Expression *& arg : appExpr->args ) {
327	// each argument with address-of requires a cast
328	addCast = true;
329	arg = arg->acceptMutator( *visitor );
330	}
331	}
332
333	void AddrRef::premutate( SingleInit * ) {
334	GuardValue( addCast );
335	// each initialization context with address-of requires a cast
336	addCast = true;
337	}
338
339
340	Expression * ReferenceConversions::postmutate( AddressExpr * addrExpr ) {
341	// Inner expression may have been lvalue to reference conversion, which becomes an address expression.
342	// In this case, remove the outer address expression and return the argument.
343	// TODO: It's possible that this might catch too much and require a more sophisticated check.
344	return addrExpr;
345	}
346
347	Expression * ReferenceConversions::postmutate( CastExpr * castExpr ) {
348	// xxx - is it possible to convert directly between reference types with a different base? E.g.,
349	// int x;
350	// (double&)x;
351	// At the moment, I am working off of the assumption that this is illegal, thus the cast becomes redundant
352	// after this pass, so trash the cast altogether. If that changes, care must be taken to insert the correct
353	// pointer casts in the right places.
354
355	// Note: reference depth difference is the determining factor in what code is run, rather than whether something is
356	// reference type or not, since conversion still needs to occur when both types are references that differ in depth.
357
358	Type * destType = castExpr->result;
359	Type * srcType = castExpr->arg->result;
360	int depth1 = destType->referenceDepth();
361	int depth2 = srcType->referenceDepth();
362	int diff = depth1 - depth2;
363
364	if ( diff > 0 && ! srcType->get_lvalue() ) {
365	// rvalue to reference conversion -- introduce temporary
366	// know that reference depth of cast argument is 0, need to introduce n temporaries for reference depth of n, e.g.
367	// (int &&&)3;
368	// becomes
369	// int __ref_tmp_0 = 3;
370	// int & __ref_tmp_1 = _&_ref_tmp_0;
371	// int && __ref_tmp_2 = &__ref_tmp_1;
372	// &__ref_tmp_2;
373	// the last & comes from the remaining reference conversion code
374	SemanticWarning( castExpr->arg->location, Warning::RvalueToReferenceConversion, toCString( castExpr->arg ) );
375
376	static UniqueName tempNamer( "__ref_tmp_" );
377	ObjectDecl * temp = ObjectDecl::newObject( tempNamer.newName(), castExpr->arg->result->clone(), new SingleInit( castExpr->arg ) );
378	PRINT( std::cerr << "made temp: " << temp << std::endl; )
379	stmtsToAddBefore.push_back( new DeclStmt( temp ) );
380	for ( int i = 0; i < depth1-1; i++ ) { // xxx - maybe this should be diff-1? check how this works with reference type for srcType
381	ObjectDecl * newTemp = ObjectDecl::newObject( tempNamer.newName(), new ReferenceType( Type::Qualifiers(), temp->type->clone() ), new SingleInit( new AddressExpr( new VariableExpr( temp ) ) ) );
382	PRINT( std::cerr << "made temp" << i << ": " << newTemp << std::endl; )
383	stmtsToAddBefore.push_back( new DeclStmt( newTemp ) );
384	temp = newTemp;
385	}
386	// update diff so that remaining code works out correctly
387	castExpr->arg = new VariableExpr( temp );
388	PRINT( std::cerr << "update cast to: " << castExpr << std::endl; )
389	srcType = castExpr->arg->result;
390	depth2 = srcType->referenceDepth();
391	diff = depth1 - depth2;
392	assert( diff == 1 );
393	}
394
395	// handle conversion between different depths
396	PRINT (
397	if ( depth1 \|\| depth2 ) {
398	std::cerr << "destType: " << destType << " / srcType: " << srcType << std::endl;
399	std::cerr << "depth: " << depth1 << " / " << depth2 << std::endl;
400	}
401	)
402	if ( diff > 0 ) {
403	// conversion to type with more depth (e.g. int & -> int &&): add address-of for each level of difference
404	Expression * ret = castExpr->arg;
405	for ( int i = 0; i < diff; ++i ) {
406	ret = new AddressExpr( ret );
407	}
408	if ( srcType->get_lvalue() && srcType->get_qualifiers() != strict_dynamic_cast<ReferenceType *>( destType )->base->get_qualifiers() ) {
409	// must keep cast if cast-to type is different from the actual type
410	castExpr->arg = ret;
411	return castExpr;
412	}
413	ret->env = castExpr->env;
414	delete ret->result;
415	ret->result = castExpr->result;
416	castExpr->env = nullptr;
417	castExpr->arg = nullptr;
418	castExpr->result = nullptr;
419	delete castExpr;
420	return ret;
421	} else if ( diff < 0 ) {
422	// conversion to type with less depth (e.g. int && -> int &): add dereferences for each level of difference
423	diff = -diff; // care only about magnitude now
424	Expression * ret = castExpr->arg;
425	for ( int i = 0; i < diff; ++i ) {
426	ret = mkDeref( ret );
427	// xxx - try removing one reference here? actually, looks like mkDeref already does this, so more closely look at the types generated.
428	}
429	if ( ! ResolvExpr::typesCompatibleIgnoreQualifiers( destType->stripReferences(), srcType->stripReferences(), SymTab::Indexer() ) ) {
430	// must keep cast if types are different
431	castExpr->arg = ret;
432	return castExpr;
433	}
434	ret->env = castExpr->env;
435	delete ret->result;
436	ret->result = castExpr->result;
437	ret->result->set_lvalue( true ); // ensure result is lvalue
438	castExpr->env = nullptr;
439	castExpr->arg = nullptr;
440	castExpr->result = nullptr;
441	delete castExpr;
442	return ret;
443	} else {
444	assert( diff == 0 );
445	// conversion between references of the same depth
446	if ( ResolvExpr::typesCompatible( castExpr->result, castExpr->arg->result, SymTab::Indexer() ) && castExpr->isGenerated ) {
447	// Remove useless generated casts
448	PRINT(
449	std::cerr << "types are compatible, removing cast: " << castExpr << std::endl;
450	std::cerr << "-- " << castExpr->result << std::endl;
451	std::cerr << "-- " << castExpr->arg->result << std::endl;
452	)
453	Expression * ret = castExpr->arg;
454	castExpr->arg = nullptr;
455	std::swap( castExpr->env, ret->env );
456	delete castExpr;
457	return ret;
458	}
459	return castExpr;
460	}
461	}
462
463	Type * ReferenceTypeElimination::postmutate( ReferenceType * refType ) {
464	Type * base = refType->base;
465	Type::Qualifiers qualifiers = refType->get_qualifiers();
466	refType->base = nullptr;
467	delete refType;
468	return new PointerType( qualifiers, base );
469	}
470
471	template<typename Func>
472	Expression * GeneralizedLvalue::applyTransformation( Expression * expr, Expression * arg, Func mkExpr ) {
473	if ( CommaExpr * commaExpr = dynamic_cast< CommaExpr * >( arg ) ) {
474	Expression * arg1 = commaExpr->arg1->clone();
475	Expression * arg2 = commaExpr->arg2->clone();
476	Expression * ret = new CommaExpr( arg1, mkExpr( arg2 )->acceptMutator( *visitor ) );
477	ret->env = expr->env;
478	expr->env = nullptr;
479	delete expr;
480	return ret;
481	} else if ( ConditionalExpr * condExpr = dynamic_cast< ConditionalExpr * >( arg ) ) {
482	Expression * arg1 = condExpr->arg1->clone();
483	Expression * arg2 = condExpr->arg2->clone();
484	Expression * arg3 = condExpr->arg3->clone();
485	ConditionalExpr * ret = new ConditionalExpr( arg1, mkExpr( arg2 )->acceptMutator( visitor ), mkExpr( arg3 )->acceptMutator( visitor ) );
486	ret->env = expr->env;
487	expr->env = nullptr;
488	delete expr;
489
490	// conditional expr type may not be either of the argument types, need to unify
491	using namespace ResolvExpr;
492	Type* commonType = nullptr;
493	TypeEnvironment newEnv;
494	AssertionSet needAssertions, haveAssertions;
495	OpenVarSet openVars;
496	unify( ret->arg2->result, ret->arg3->result, newEnv, needAssertions, haveAssertions, openVars, SymTab::Indexer(), commonType );
497	ret->result = commonType ? commonType : ret->arg2->result->clone();
498	return ret;
499	}
500	return expr;
501	}
502
503	Expression * GeneralizedLvalue::postmutate( MemberExpr * memExpr ) {
504	return applyTransformation( memExpr, memExpr->aggregate, [=]( Expression * aggr ) { return new MemberExpr( memExpr->member, aggr ); } );
505	}
506
507	Expression * GeneralizedLvalue::postmutate( AddressExpr * addrExpr ) {
508	return applyTransformation( addrExpr, addrExpr->arg, []( Expression * arg ) { return new AddressExpr( arg ); } );
509	}
510
511	Expression * CollapseAddrDeref::postmutate( AddressExpr * addrExpr ) {
512	Expression * arg = addrExpr->arg;
513	if ( isIntrinsicReference( arg ) ) {
514	std::string fname = InitTweak::getFunctionName( arg );
515	if ( fname == "*?" ) {
516	Expression *& arg0 = InitTweak::getCallArg( arg, 0 );
517	Expression * ret = arg0;
518	ret->set_env( addrExpr->env );
519	arg0 = nullptr;
520	addrExpr->env = nullptr;
521	delete addrExpr;
522	return ret;
523	}
524	} else if ( CastExpr * castExpr = dynamic_cast< CastExpr * > ( arg ) ) {
525	// need to move cast to pointer type out a level since address of pointer
526	// is not valid C code (can be introduced in prior passes, e.g., InstantiateGeneric)
527	if ( InitTweak::getPointerBase( castExpr->result ) ) {
528	addrExpr->arg = castExpr->arg;
529	castExpr->arg = addrExpr;
530	castExpr->result = new PointerType( Type::Qualifiers(), castExpr->result );
531	return castExpr;
532	}
533	}
534	return addrExpr;
535	}
536
537	Expression * CollapseAddrDeref::postmutate( ApplicationExpr * appExpr ) {
538	if ( isIntrinsicReference( appExpr ) ) {
539	std::string fname = InitTweak::getFunctionName( appExpr );
540	if ( fname == "*?" ) {
541	Expression * arg = InitTweak::getCallArg( appExpr, 0 );
542	// xxx - this isn't right, because it can remove casts that should be there...
543	// while ( CastExpr * castExpr = dynamic_cast< CastExpr * >( arg ) ) {
544	// arg = castExpr->get_arg();
545	// }
546	if ( AddressExpr * addrExpr = dynamic_cast< AddressExpr * >( arg ) ) {
547	Expression * ret = addrExpr->arg;
548	ret->env = appExpr->env;
549	addrExpr->arg = nullptr;
550	appExpr->env = nullptr;
551	delete appExpr;
552	return ret;
553	}
554	}
555	}
556	return appExpr;
557	}
558	} // namespace
559	} // namespace GenPoly
560
561	// Local Variables: //
562	// tab-width: 4 //
563	// mode: c++ //
564	// compile-command: "make install" //
565	// End: //

Note: See TracBrowser for help on using the repository browser.

Download in other formats: