1	//===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	// This contains code to emit Decl nodes as LLVM code.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#include "CGBlocks.h"
14	#include "CGCXXABI.h"
15	#include "CGCleanup.h"
16	#include "CGDebugInfo.h"
17	#include "CGOpenCLRuntime.h"
18	#include "CGOpenMPRuntime.h"
19	#include "CodeGenFunction.h"
20	#include "CodeGenModule.h"
21	#include "ConstantEmitter.h"
22	#include "PatternInit.h"
23	#include "TargetInfo.h"
24	#include "clang/AST/ASTContext.h"
25	#include "clang/AST/Attr.h"
26	#include "clang/AST/CharUnits.h"
27	#include "clang/AST/Decl.h"
28	#include "clang/AST/DeclObjC.h"
29	#include "clang/AST/DeclOpenMP.h"
30	#include "clang/Basic/CodeGenOptions.h"
31	#include "clang/Basic/SourceManager.h"
32	#include "clang/Basic/TargetInfo.h"
33	#include "clang/CodeGen/CGFunctionInfo.h"
34	#include "clang/Sema/Sema.h"
35	#include "llvm/Analysis/ValueTracking.h"
36	#include "llvm/IR/DataLayout.h"
37	#include "llvm/IR/GlobalVariable.h"
38	#include "llvm/IR/Intrinsics.h"
39	#include "llvm/IR/Type.h"
40	#include <optional>
41
42	using namespace clang;
43	using namespace CodeGen;
44
45	static_assert(clang::Sema::MaximumAlignment <= llvm::Value::MaximumAlignment,
46	"Clang max alignment greater than what LLVM supports?");
47
48	void CodeGenFunction::EmitDecl(const Decl &D) {
49	switch (D.getKind()) {
50	case Decl::BuiltinTemplate:
51	case Decl::TranslationUnit:
52	case Decl::ExternCContext:
53	case Decl::Namespace:
54	case Decl::UnresolvedUsingTypename:
55	case Decl::ClassTemplateSpecialization:
56	case Decl::ClassTemplatePartialSpecialization:
57	case Decl::VarTemplateSpecialization:
58	case Decl::VarTemplatePartialSpecialization:
59	case Decl::TemplateTypeParm:
60	case Decl::UnresolvedUsingValue:
61	case Decl::NonTypeTemplateParm:
62	case Decl::CXXDeductionGuide:
63	case Decl::CXXMethod:
64	case Decl::CXXConstructor:
65	case Decl::CXXDestructor:
66	case Decl::CXXConversion:
67	case Decl::Field:
68	case Decl::MSProperty:
69	case Decl::IndirectField:
70	case Decl::ObjCIvar:
71	case Decl::ObjCAtDefsField:
72	case Decl::ParmVar:
73	case Decl::ImplicitParam:
74	case Decl::ClassTemplate:
75	case Decl::VarTemplate:
76	case Decl::FunctionTemplate:
77	case Decl::TypeAliasTemplate:
78	case Decl::TemplateTemplateParm:
79	case Decl::ObjCMethod:
80	case Decl::ObjCCategory:
81	case Decl::ObjCProtocol:
82	case Decl::ObjCInterface:
83	case Decl::ObjCCategoryImpl:
84	case Decl::ObjCImplementation:
85	case Decl::ObjCProperty:
86	case Decl::ObjCCompatibleAlias:
87	case Decl::PragmaComment:
88	case Decl::PragmaDetectMismatch:
89	case Decl::AccessSpec:
90	case Decl::LinkageSpec:
91	case Decl::Export:
92	case Decl::ObjCPropertyImpl:
93	case Decl::FileScopeAsm:
94	case Decl::TopLevelStmt:
95	case Decl::Friend:
96	case Decl::FriendTemplate:
97	case Decl::Block:
98	case Decl::Captured:
99	case Decl::UsingShadow:
100	case Decl::ConstructorUsingShadow:
101	case Decl::ObjCTypeParam:
102	case Decl::Binding:
103	case Decl::UnresolvedUsingIfExists:
104	case Decl::HLSLBuffer:
105	llvm_unreachable("Declaration should not be in declstmts!");
106	case Decl::Record: // struct/union/class X;
107	case Decl::CXXRecord: // struct/union/class X; [C++]
108	if (CGDebugInfo *DI = getDebugInfo())
109	if (cast<RecordDecl>(Val: D).getDefinition())
110	DI->EmitAndRetainType(Ty: getContext().getRecordType(Decl: cast<RecordDecl>(Val: &D)));
111	return;
112	case Decl::Enum: // enum X;
113	if (CGDebugInfo *DI = getDebugInfo())
114	if (cast<EnumDecl>(Val: D).getDefinition())
115	DI->EmitAndRetainType(Ty: getContext().getEnumType(Decl: cast<EnumDecl>(Val: &D)));
116	return;
117	case Decl::Function: // void X();
118	case Decl::EnumConstant: // enum ? { X = ? }
119	case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
120	case Decl::Label: // __label__ x;
121	case Decl::Import:
122	case Decl::MSGuid: // __declspec(uuid("..."))
123	case Decl::UnnamedGlobalConstant:
124	case Decl::TemplateParamObject:
125	case Decl::OMPThreadPrivate:
126	case Decl::OMPAllocate:
127	case Decl::OMPCapturedExpr:
128	case Decl::OMPRequires:
129	case Decl::Empty:
130	case Decl::Concept:
131	case Decl::ImplicitConceptSpecialization:
132	case Decl::LifetimeExtendedTemporary:
133	case Decl::RequiresExprBody:
134	// None of these decls require codegen support.
135	return;
136
137	case Decl::NamespaceAlias:
138	if (CGDebugInfo *DI = getDebugInfo())
139	DI->EmitNamespaceAlias(NA: cast<NamespaceAliasDecl>(Val: D));
140	return;
141	case Decl::Using: // using X; [C++]
142	if (CGDebugInfo *DI = getDebugInfo())
143	DI->EmitUsingDecl(UD: cast<UsingDecl>(Val: D));
144	return;
145	case Decl::UsingEnum: // using enum X; [C++]
146	if (CGDebugInfo *DI = getDebugInfo())
147	DI->EmitUsingEnumDecl(UD: cast<UsingEnumDecl>(Val: D));
148	return;
149	case Decl::UsingPack:
150	for (auto *Using : cast<UsingPackDecl>(Val: D).expansions())
151	EmitDecl(*Using);
152	return;
153	case Decl::UsingDirective: // using namespace X; [C++]
154	if (CGDebugInfo *DI = getDebugInfo())
155	DI->EmitUsingDirective(UD: cast<UsingDirectiveDecl>(Val: D));
156	return;
157	case Decl::Var:
158	case Decl::Decomposition: {
159	const VarDecl &VD = cast<VarDecl>(Val: D);
160	assert(VD.isLocalVarDecl() &&
161	"Should not see file-scope variables inside a function!");
162	EmitVarDecl(D: VD);
163	if (auto *DD = dyn_cast<DecompositionDecl>(Val: &VD))
164	for (auto *B : DD->bindings())
165	if (auto *HD = B->getHoldingVar())
166	EmitVarDecl(D: *HD);
167	return;
168	}
169
170	case Decl::OMPDeclareReduction:
171	return CGM.EmitOMPDeclareReduction(D: cast<OMPDeclareReductionDecl>(Val: &D), CGF: this);
172
173	case Decl::OMPDeclareMapper:
174	return CGM.EmitOMPDeclareMapper(D: cast<OMPDeclareMapperDecl>(Val: &D), CGF: this);
175
176	case Decl::Typedef: // typedef int X;
177	case Decl::TypeAlias: { // using X = int; [C++0x]
178	QualType Ty = cast<TypedefNameDecl>(Val: D).getUnderlyingType();
179	if (CGDebugInfo *DI = getDebugInfo())
180	DI->EmitAndRetainType(Ty);
181	if (Ty->isVariablyModifiedType())
182	EmitVariablyModifiedType(Ty);
183	return;
184	}
185	}
186	}
187
188	/// EmitVarDecl - This method handles emission of any variable declaration
189	/// inside a function, including static vars etc.
190	void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
191	if (D.hasExternalStorage())
192	// Don't emit it now, allow it to be emitted lazily on its first use.
193	return;
194
195	// Some function-scope variable does not have static storage but still
196	// needs to be emitted like a static variable, e.g. a function-scope
197	// variable in constant address space in OpenCL.
198	if (D.getStorageDuration() != SD_Automatic) {
199	// Static sampler variables translated to function calls.
200	if (D.getType()->isSamplerT())
201	return;
202
203	llvm::GlobalValue::LinkageTypes Linkage =
204	CGM.getLLVMLinkageVarDefinition(VD: &D);
205
206	// FIXME: We need to force the emission/use of a guard variable for
207	// some variables even if we can constant-evaluate them because
208	// we can't guarantee every translation unit will constant-evaluate them.
209
210	return EmitStaticVarDecl(D, Linkage);
211	}
212
213	if (D.getType().getAddressSpace() == LangAS::opencl_local)
214	return CGM.getOpenCLRuntime().EmitWorkGroupLocalVarDecl(CGF&: *this, D);
215
216	assert(D.hasLocalStorage());
217	return EmitAutoVarDecl(D);
218	}
219
220	static std::string getStaticDeclName(CodeGenModule &CGM, const VarDecl &D) {
221	if (CGM.getLangOpts().CPlusPlus)
222	return CGM.getMangledName(GD: &D).str();
223
224	// If this isn't C++, we don't need a mangled name, just a pretty one.
225	assert(!D.isExternallyVisible() && "name shouldn't matter");
226	std::string ContextName;
227	const DeclContext *DC = D.getDeclContext();
228	if (auto *CD = dyn_cast<CapturedDecl>(DC))
229	DC = cast<DeclContext>(CD->getNonClosureContext());
230	if (const auto *FD = dyn_cast<FunctionDecl>(DC))
231	ContextName = std::string(CGM.getMangledName(GD: FD));
232	else if (const auto *BD = dyn_cast<BlockDecl>(DC))
233	ContextName = std::string(CGM.getBlockMangledName(GD: GlobalDecl(), BD: BD));
234	else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(DC))
235	ContextName = OMD->getSelector().getAsString();
236	else
237	llvm_unreachable("Unknown context for static var decl");
238
239	ContextName += "." + D.getNameAsString();
240	return ContextName;
241	}
242
243	llvm::Constant *CodeGenModule::getOrCreateStaticVarDecl(
244	const VarDecl &D, llvm::GlobalValue::LinkageTypes Linkage) {
245	// In general, we don't always emit static var decls once before we reference
246	// them. It is possible to reference them before emitting the function that
247	// contains them, and it is possible to emit the containing function multiple
248	// times.
249	if (llvm::Constant *ExistingGV = StaticLocalDeclMap[&D])
250	return ExistingGV;
251
252	QualType Ty = D.getType();
253	assert(Ty->isConstantSizeType() && "VLAs can't be static");
254
255	// Use the label if the variable is renamed with the asm-label extension.
256	std::string Name;
257	if (D.hasAttr<AsmLabelAttr>())
258	Name = std::string(getMangledName(GD: &D));
259	else
260	Name = getStaticDeclName(CGM&: *this, D);
261
262	llvm::Type *LTy = getTypes().ConvertTypeForMem(T: Ty);
263	LangAS AS = GetGlobalVarAddressSpace(D: &D);
264	unsigned TargetAS = getContext().getTargetAddressSpace(AS);
265
266	// OpenCL variables in local address space and CUDA shared
267	// variables cannot have an initializer.
268	llvm::Constant *Init = nullptr;
269	if (Ty.getAddressSpace() == LangAS::opencl_local ||
270	D.hasAttr<CUDASharedAttr>() || D.hasAttr<LoaderUninitializedAttr>())
271	Init = llvm::UndefValue::get(T: LTy);
272	else
273	Init = EmitNullConstant(T: Ty);
274
275	llvm::GlobalVariable *GV = new llvm::GlobalVariable(
276	getModule(), LTy, Ty.isConstant(Ctx: getContext()), Linkage, Init, Name,
277	nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS);
278	GV->setAlignment(getContext().getDeclAlign(&D).getAsAlign());
279
280	if (supportsCOMDAT() && GV->isWeakForLinker())
281	GV->setComdat(TheModule.getOrInsertComdat(Name: GV->getName()));
282
283	if (D.getTLSKind())
284	setTLSMode(GV, D);
285
286	setGVProperties(GV, GD: &D);
287	getTargetCodeGenInfo().setTargetAttributes(D: cast<Decl>(Val: &D), GV, M&: *this);
288
289	// Make sure the result is of the correct type.
290	LangAS ExpectedAS = Ty.getAddressSpace();
291	llvm::Constant *Addr = GV;
292	if (AS != ExpectedAS) {
293	Addr = getTargetCodeGenInfo().performAddrSpaceCast(
294	CGM&: *this, V: GV, SrcAddr: AS, DestAddr: ExpectedAS,
295	DestTy: llvm::PointerType::get(C&: getLLVMContext(),
296	AddressSpace: getContext().getTargetAddressSpace(AS: ExpectedAS)));
297	}
298
299	setStaticLocalDeclAddress(D: &D, C: Addr);
300
301	// Ensure that the static local gets initialized by making sure the parent
302	// function gets emitted eventually.
303	const Decl *DC = cast<Decl>(D.getDeclContext());
304
305	// We can't name blocks or captured statements directly, so try to emit their
306	// parents.
307	if (isa<BlockDecl>(Val: DC) || isa<CapturedDecl>(Val: DC)) {
308	DC = DC->getNonClosureContext();
309	// FIXME: Ensure that global blocks get emitted.
310	if (!DC)
311	return Addr;
312	}
313
314	GlobalDecl GD;
315	if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
316	GD = GlobalDecl(CD, Ctor_Base);
317	else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
318	GD = GlobalDecl(DD, Dtor_Base);
319	else if (const auto *FD = dyn_cast<FunctionDecl>(DC))
320	GD = GlobalDecl(FD);
321	else {
322	// Don't do anything for Obj-C method decls or global closures. We should
323	// never defer them.
324	assert(isa<ObjCMethodDecl>(DC) && "unexpected parent code decl");
325	}
326	if (GD.getDecl()) {
327	// Disable emission of the parent function for the OpenMP device codegen.
328	CGOpenMPRuntime::DisableAutoDeclareTargetRAII NoDeclTarget(*this);
329	(void)GetAddrOfGlobal(GD);
330	}
331
332	return Addr;
333	}
334
335	/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
336	/// global variable that has already been created for it. If the initializer
337	/// has a different type than GV does, this may free GV and return a different
338	/// one. Otherwise it just returns GV.
339	llvm::GlobalVariable *
340	CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
341	llvm::GlobalVariable *GV) {
342	ConstantEmitter emitter(*this);
343	llvm::Constant *Init = emitter.tryEmitForInitializer(D);
344
345	// If constant emission failed, then this should be a C++ static
346	// initializer.
347	if (!Init) {
348	if (!getLangOpts().CPlusPlus)
349	CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
350	else if (D.hasFlexibleArrayInit(Ctx: getContext()))
351	CGM.ErrorUnsupported(D.getInit(), "flexible array initializer");
352	else if (HaveInsertPoint()) {
353	// Since we have a static initializer, this global variable can't
354	// be constant.
355	GV->setConstant(false);
356
357	EmitCXXGuardedInit(D, DeclPtr: GV, /*PerformInit*/true);
358	}
359	return GV;
360	}
361
362	#ifndef NDEBUG
363	CharUnits VarSize = CGM.getContext().getTypeSizeInChars(D.getType()) +
364	D.getFlexibleArrayInitChars(Ctx: getContext());
365	CharUnits CstSize = CharUnits::fromQuantity(
366	Quantity: CGM.getDataLayout().getTypeAllocSize(Ty: Init->getType()));
367	assert(VarSize == CstSize && "Emitted constant has unexpected size");
368	#endif
369
370	// The initializer may differ in type from the global. Rewrite
371	// the global to match the initializer. (We have to do this
372	// because some types, like unions, can't be completely represented
373	// in the LLVM type system.)
374	if (GV->getValueType() != Init->getType()) {
375	llvm::GlobalVariable *OldGV = GV;
376
377	GV = new llvm::GlobalVariable(
378	CGM.getModule(), Init->getType(), OldGV->isConstant(),
379	OldGV->getLinkage(), Init, "",
380	/*InsertBefore*/ OldGV, OldGV->getThreadLocalMode(),
381	OldGV->getType()->getPointerAddressSpace());
382	GV->setVisibility(OldGV->getVisibility());
383	GV->setDSOLocal(OldGV->isDSOLocal());
384	GV->setComdat(OldGV->getComdat());
385
386	// Steal the name of the old global
387	GV->takeName(V: OldGV);
388
389	// Replace all uses of the old global with the new global
390	OldGV->replaceAllUsesWith(V: GV);
391
392	// Erase the old global, since it is no longer used.
393	OldGV->eraseFromParent();
394	}
395
396	bool NeedsDtor =
397	D.needsDestruction(Ctx: getContext()) == QualType::DK_cxx_destructor;
398
399	GV->setConstant(
400	D.getType().isConstantStorage(getContext(), true, !NeedsDtor));
401	GV->setInitializer(Init);
402
403	emitter.finalize(global: GV);
404
405	if (NeedsDtor && HaveInsertPoint()) {
406	// We have a constant initializer, but a nontrivial destructor. We still
407	// need to perform a guarded "initialization" in order to register the
408	// destructor.
409	EmitCXXGuardedInit(D, DeclPtr: GV, /*PerformInit*/false);
410	}
411
412	return GV;
413	}
414
415	void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
416	llvm::GlobalValue::LinkageTypes Linkage) {
417	// Check to see if we already have a global variable for this
418	// declaration. This can happen when double-emitting function
419	// bodies, e.g. with complete and base constructors.
420	llvm::Constant *addr = CGM.getOrCreateStaticVarDecl(D, Linkage);
421	CharUnits alignment = getContext().getDeclAlign(&D);
422
423	// Store into LocalDeclMap before generating initializer to handle
424	// circular references.
425	llvm::Type *elemTy = ConvertTypeForMem(T: D.getType());
426	setAddrOfLocalVar(VD: &D, Addr: Address(addr, elemTy, alignment));
427
428	// We can't have a VLA here, but we can have a pointer to a VLA,
429	// even though that doesn't really make any sense.
430	// Make sure to evaluate VLA bounds now so that we have them for later.
431	if (D.getType()->isVariablyModifiedType())
432	EmitVariablyModifiedType(Ty: D.getType());
433
434	// Save the type in case adding the initializer forces a type change.
435	llvm::Type *expectedType = addr->getType();
436
437	llvm::GlobalVariable *var =
438	cast<llvm::GlobalVariable>(Val: addr->stripPointerCasts());
439
440	// CUDA's local and local static __shared__ variables should not
441	// have any non-empty initializers. This is ensured by Sema.
442	// Whatever initializer such variable may have when it gets here is
443	// a no-op and should not be emitted.
444	bool isCudaSharedVar = getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
445	D.hasAttr<CUDASharedAttr>();
446	// If this value has an initializer, emit it.
447	if (D.getInit() && !isCudaSharedVar)
448	var = AddInitializerToStaticVarDecl(D, GV: var);
449
450	var->setAlignment(alignment.getAsAlign());
451
452	if (D.hasAttr<AnnotateAttr>())
453	CGM.AddGlobalAnnotations(&D, var);
454
455	if (auto *SA = D.getAttr<PragmaClangBSSSectionAttr>())
456	var->addAttribute("bss-section", SA->getName());
457	if (auto *SA = D.getAttr<PragmaClangDataSectionAttr>())
458	var->addAttribute("data-section", SA->getName());
459	if (auto *SA = D.getAttr<PragmaClangRodataSectionAttr>())
460	var->addAttribute("rodata-section", SA->getName());
461	if (auto *SA = D.getAttr<PragmaClangRelroSectionAttr>())
462	var->addAttribute("relro-section", SA->getName());
463
464	if (const SectionAttr *SA = D.getAttr<SectionAttr>())
465	var->setSection(SA->getName());
466
467	if (D.hasAttr<RetainAttr>())
468	CGM.addUsedGlobal(GV: var);
469	else if (D.hasAttr<UsedAttr>())
470	CGM.addUsedOrCompilerUsedGlobal(GV: var);
471
472	if (CGM.getCodeGenOpts().KeepPersistentStorageVariables)
473	CGM.addUsedOrCompilerUsedGlobal(GV: var);
474
475	// We may have to cast the constant because of the initializer
476	// mismatch above.
477	//
478	// FIXME: It is really dangerous to store this in the map; if anyone
479	// RAUW's the GV uses of this constant will be invalid.
480	llvm::Constant *castedAddr =
481	llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(C: var, Ty: expectedType);
482	LocalDeclMap.find(&D)->second = Address(castedAddr, elemTy, alignment);
483	CGM.setStaticLocalDeclAddress(D: &D, C: castedAddr);
484
485	CGM.getSanitizerMetadata()->reportGlobal(GV: var, D);
486
487	// Emit global variable debug descriptor for static vars.
488	CGDebugInfo *DI = getDebugInfo();
489	if (DI && CGM.getCodeGenOpts().hasReducedDebugInfo()) {
490	DI->setLocation(D.getLocation());
491	DI->EmitGlobalVariable(GV: var, Decl: &D);
492	}
493	}
494
495	namespace {
496	struct DestroyObject final : EHScopeStack::Cleanup {
497	DestroyObject(Address addr, QualType type,
498	CodeGenFunction::Destroyer *destroyer,
499	bool useEHCleanupForArray)
500	: addr(addr), type(type), destroyer(destroyer),
501	useEHCleanupForArray(useEHCleanupForArray) {}
502
503	Address addr;
504	QualType type;
505	CodeGenFunction::Destroyer *destroyer;
506	bool useEHCleanupForArray;
507
508	void Emit(CodeGenFunction &CGF, Flags flags) override {
509	// Don't use an EH cleanup recursively from an EH cleanup.
510	bool useEHCleanupForArray =
511	flags.isForNormalCleanup() && this->useEHCleanupForArray;
512
513	CGF.emitDestroy(addr, type, destroyer, useEHCleanupForArray);
514	}
515	};
516
517	template <class Derived>
518	struct DestroyNRVOVariable : EHScopeStack::Cleanup {
519	DestroyNRVOVariable(Address addr, QualType type, llvm::Value *NRVOFlag)
520	: NRVOFlag(NRVOFlag), Loc(addr), Ty(type) {}
521
522	llvm::Value *NRVOFlag;
523	Address Loc;
524	QualType Ty;
525
526	void Emit(CodeGenFunction &CGF, Flags flags) override {
527	// Along the exceptions path we always execute the dtor.
528	bool NRVO = flags.isForNormalCleanup() && NRVOFlag;
529
530	llvm::BasicBlock *SkipDtorBB = nullptr;
531	if (NRVO) {
532	// If we exited via NRVO, we skip the destructor call.
533	llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock(name: "nrvo.unused");
534	SkipDtorBB = CGF.createBasicBlock(name: "nrvo.skipdtor");
535	llvm::Value *DidNRVO =
536	CGF.Builder.CreateFlagLoad(Addr: NRVOFlag, Name: "nrvo.val");
537	CGF.Builder.CreateCondBr(Cond: DidNRVO, True: SkipDtorBB, False: RunDtorBB);
538	CGF.EmitBlock(BB: RunDtorBB);
539	}
540
541	static_cast<Derived *>(this)->emitDestructorCall(CGF);
542
543	if (NRVO) CGF.EmitBlock(BB: SkipDtorBB);
544	}
545
546	virtual ~DestroyNRVOVariable() = default;
547	};
548
549	struct DestroyNRVOVariableCXX final
550	: DestroyNRVOVariable<DestroyNRVOVariableCXX> {
551	DestroyNRVOVariableCXX(Address addr, QualType type,
552	const CXXDestructorDecl *Dtor, llvm::Value *NRVOFlag)
553	: DestroyNRVOVariable<DestroyNRVOVariableCXX>(addr, type, NRVOFlag),
554	Dtor(Dtor) {}
555
556	const CXXDestructorDecl *Dtor;
557
558	void emitDestructorCall(CodeGenFunction &CGF) {
559	CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
560	/*ForVirtualBase=*/false,
561	/*Delegating=*/false, Loc, Ty);
562	}
563	};
564
565	struct DestroyNRVOVariableC final
566	: DestroyNRVOVariable<DestroyNRVOVariableC> {
567	DestroyNRVOVariableC(Address addr, llvm::Value *NRVOFlag, QualType Ty)
568	: DestroyNRVOVariable<DestroyNRVOVariableC>(addr, Ty, NRVOFlag) {}
569
570	void emitDestructorCall(CodeGenFunction &CGF) {
571	CGF.destroyNonTrivialCStruct(CGF, Loc, Ty);
572	}
573	};
574
575	struct CallStackRestore final : EHScopeStack::Cleanup {
576	Address Stack;
577	CallStackRestore(Address Stack) : Stack(Stack) {}
578	bool isRedundantBeforeReturn() override { return true; }
579	void Emit(CodeGenFunction &CGF, Flags flags) override {
580	llvm::Value *V = CGF.Builder.CreateLoad(Addr: Stack);
581	CGF.Builder.CreateStackRestore(Ptr: V);
582	}
583	};
584
585	struct KmpcAllocFree final : EHScopeStack::Cleanup {
586	std::pair<llvm::Value *, llvm::Value *> AddrSizePair;
587	KmpcAllocFree(const std::pair<llvm::Value *, llvm::Value *> &AddrSizePair)
588	: AddrSizePair(AddrSizePair) {}
589	void Emit(CodeGenFunction &CGF, Flags EmissionFlags) override {
590	auto &RT = CGF.CGM.getOpenMPRuntime();
591	RT.getKmpcFreeShared(CGF, AddrSizePair);
592	}
593	};
594
595	struct ExtendGCLifetime final : EHScopeStack::Cleanup {
596	const VarDecl &Var;
597	ExtendGCLifetime(const VarDecl *var) : Var(*var) {}
598
599	void Emit(CodeGenFunction &CGF, Flags flags) override {
600	// Compute the address of the local variable, in case it's a
601	// byref or something.
602	DeclRefExpr DRE(CGF.getContext(), const_cast<VarDecl *>(&Var), false,
603	Var.getType(), VK_LValue, SourceLocation());
604	llvm::Value *value = CGF.EmitLoadOfScalar(lvalue: CGF.EmitDeclRefLValue(E: &DRE),
605	Loc: SourceLocation());
606	CGF.EmitExtendGCLifetime(object: value);
607	}
608	};
609
610	struct CallCleanupFunction final : EHScopeStack::Cleanup {
611	llvm::Constant *CleanupFn;
612	const CGFunctionInfo &FnInfo;
613	const VarDecl &Var;
614
615	CallCleanupFunction(llvm::Constant *CleanupFn, const CGFunctionInfo *Info,
616	const VarDecl *Var)
617	: CleanupFn(CleanupFn), FnInfo(*Info), Var(*Var) {}
618
619	void Emit(CodeGenFunction &CGF, Flags flags) override {
620	DeclRefExpr DRE(CGF.getContext(), const_cast<VarDecl *>(&Var), false,
621	Var.getType(), VK_LValue, SourceLocation());
622	// Compute the address of the local variable, in case it's a byref
623	// or something.
624	llvm::Value *Addr = CGF.EmitDeclRefLValue(E: &DRE).getPointer(CGF);
625
626	// In some cases, the type of the function argument will be different from
627	// the type of the pointer. An example of this is
628	// void f(void* arg);
629	// __attribute__((cleanup(f))) void *g;
630	//
631	// To fix this we insert a bitcast here.
632	QualType ArgTy = FnInfo.arg_begin()->type;
633	llvm::Value *Arg =
634	CGF.Builder.CreateBitCast(V: Addr, DestTy: CGF.ConvertType(T: ArgTy));
635
636	CallArgList Args;
637	Args.add(rvalue: RValue::get(V: Arg),
638	type: CGF.getContext().getPointerType(Var.getType()));
639	auto Callee = CGCallee::forDirect(functionPtr: CleanupFn);
640	CGF.EmitCall(CallInfo: FnInfo, Callee, ReturnValue: ReturnValueSlot(), Args);
641	}
642	};
643	} // end anonymous namespace
644
645	/// EmitAutoVarWithLifetime - Does the setup required for an automatic
646	/// variable with lifetime.
647	static void EmitAutoVarWithLifetime(CodeGenFunction &CGF, const VarDecl &var,
648	Address addr,
649	Qualifiers::ObjCLifetime lifetime) {
650	switch (lifetime) {
651	case Qualifiers::OCL_None:
652	llvm_unreachable("present but none");
653
654	case Qualifiers::OCL_ExplicitNone:
655	// nothing to do
656	break;
657
658	case Qualifiers::OCL_Strong: {
659	CodeGenFunction::Destroyer *destroyer =
660	(var.hasAttr<ObjCPreciseLifetimeAttr>()
661	? CodeGenFunction::destroyARCStrongPrecise
662	: CodeGenFunction::destroyARCStrongImprecise);
663
664	CleanupKind cleanupKind = CGF.getARCCleanupKind();
665	CGF.pushDestroy(cleanupKind, addr, var.getType(), destroyer,
666	cleanupKind & EHCleanup);
667	break;
668	}
669	case Qualifiers::OCL_Autoreleasing:
670	// nothing to do
671	break;
672
673	case Qualifiers::OCL_Weak:
674	// __weak objects always get EH cleanups; otherwise, exceptions
675	// could cause really nasty crashes instead of mere leaks.
676	CGF.pushDestroy(NormalAndEHCleanup, addr, var.getType(),
677	CodeGenFunction::destroyARCWeak,
678	/*useEHCleanup*/ true);
679	break;
680	}
681	}
682
683	static bool isAccessedBy(const VarDecl &var, const Stmt *s) {
684	if (const Expr *e = dyn_cast<Expr>(Val: s)) {
685	// Skip the most common kinds of expressions that make
686	// hierarchy-walking expensive.
687	s = e = e->IgnoreParenCasts();
688
689	if (const DeclRefExpr *ref = dyn_cast<DeclRefExpr>(Val: e))
690	return (ref->getDecl() == &var);
691	if (const BlockExpr *be = dyn_cast<BlockExpr>(Val: e)) {
692	const BlockDecl *block = be->getBlockDecl();
693	for (const auto &I : block->captures()) {
694	if (I.getVariable() == &var)
695	return true;
696	}
697	}
698	}
699
700	for (const Stmt *SubStmt : s->children())
701	// SubStmt might be null; as in missing decl or conditional of an if-stmt.
702	if (SubStmt && isAccessedBy(var, s: SubStmt))
703	return true;
704
705	return false;
706	}
707
708	static bool isAccessedBy(const ValueDecl *decl, const Expr *e) {
709	if (!decl) return false;
710	if (!isa<VarDecl>(Val: decl)) return false;
711	const VarDecl *var = cast<VarDecl>(Val: decl);
712	return isAccessedBy(*var, e);
713	}
714
715	static bool tryEmitARCCopyWeakInit(CodeGenFunction &CGF,
716	const LValue &destLV, const Expr *init) {
717	bool needsCast = false;
718
719	while (auto castExpr = dyn_cast<CastExpr>(Val: init->IgnoreParens())) {
720	switch (castExpr->getCastKind()) {
721	// Look through casts that don't require representation changes.
722	case CK_NoOp:
723	case CK_BitCast:
724	case CK_BlockPointerToObjCPointerCast:
725	needsCast = true;
726	break;
727
728	// If we find an l-value to r-value cast from a __weak variable,
729	// emit this operation as a copy or move.
730	case CK_LValueToRValue: {
731	const Expr *srcExpr = castExpr->getSubExpr();
732	if (srcExpr->getType().getObjCLifetime() != Qualifiers::OCL_Weak)
733	return false;
734
735	// Emit the source l-value.
736	LValue srcLV = CGF.EmitLValue(E: srcExpr);
737
738	// Handle a formal type change to avoid asserting.
739	auto srcAddr = srcLV.getAddress(CGF);
740	if (needsCast) {
741	srcAddr =
742	srcAddr.withElementType(ElemTy: destLV.getAddress(CGF).getElementType());
743	}
744
745	// If it was an l-value, use objc_copyWeak.
746	if (srcExpr->isLValue()) {
747	CGF.EmitARCCopyWeak(dst: destLV.getAddress(CGF), src: srcAddr);
748	} else {
749	assert(srcExpr->isXValue());
750	CGF.EmitARCMoveWeak(dst: destLV.getAddress(CGF), src: srcAddr);
751	}
752	return true;
753	}
754
755	// Stop at anything else.
756	default:
757	return false;
758	}
759
760	init = castExpr->getSubExpr();
761	}
762	return false;
763	}
764
765	static void drillIntoBlockVariable(CodeGenFunction &CGF,
766	LValue &lvalue,
767	const VarDecl *var) {
768	lvalue.setAddress(CGF.emitBlockByrefAddress(baseAddr: lvalue.getAddress(CGF), V: var));
769	}
770
771	void CodeGenFunction::EmitNullabilityCheck(LValue LHS, llvm::Value *RHS,
772	SourceLocation Loc) {
773	if (!SanOpts.has(K: SanitizerKind::NullabilityAssign))
774	return;
775
776	auto Nullability = LHS.getType()->getNullability();
777	if (!Nullability || *Nullability != NullabilityKind::NonNull)
778	return;
779
780	// Check if the right hand side of the assignment is nonnull, if the left
781	// hand side must be nonnull.
782	SanitizerScope SanScope(this);
783	llvm::Value *IsNotNull = Builder.CreateIsNotNull(Arg: RHS);
784	llvm::Constant *StaticData[] = {
785	EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(T: LHS.getType()),
786	llvm::ConstantInt::get(Ty: Int8Ty, V: 0), // The LogAlignment info is unused.
787	llvm::ConstantInt::get(Ty: Int8Ty, V: TCK_NonnullAssign)};
788	EmitCheck(Checked: {{IsNotNull, SanitizerKind::NullabilityAssign}},
789	Check: SanitizerHandler::TypeMismatch, StaticArgs: StaticData, DynamicArgs: RHS);
790	}
791
792	void CodeGenFunction::EmitScalarInit(const Expr *init, const ValueDecl *D,
793	LValue lvalue, bool capturedByInit) {
794	Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
795	if (!lifetime) {
796	llvm::Value *value = EmitScalarExpr(E: init);
797	if (capturedByInit)
798	drillIntoBlockVariable(CGF&: *this, lvalue, var: cast<VarDecl>(Val: D));
799	EmitNullabilityCheck(LHS: lvalue, RHS: value, Loc: init->getExprLoc());
800	EmitStoreThroughLValue(Src: RValue::get(V: value), Dst: lvalue, isInit: true);
801	return;
802	}
803
804	if (const CXXDefaultInitExpr *DIE = dyn_cast<CXXDefaultInitExpr>(Val: init))
805	init = DIE->getExpr();
806
807	// If we're emitting a value with lifetime, we have to do the
808	// initialization *before* we leave the cleanup scopes.
809	if (auto *EWC = dyn_cast<ExprWithCleanups>(Val: init)) {
810	CodeGenFunction::RunCleanupsScope Scope(*this);
811	return EmitScalarInit(init: EWC->getSubExpr(), D, lvalue, capturedByInit);
812	}
813
814	// We have to maintain the illusion that the variable is
815	// zero-initialized. If the variable might be accessed in its
816	// initializer, zero-initialize before running the initializer, then
817	// actually perform the initialization with an assign.
818	bool accessedByInit = false;
819	if (lifetime != Qualifiers::OCL_ExplicitNone)
820	accessedByInit = (capturedByInit || isAccessedBy(decl: D, e: init));
821	if (accessedByInit) {
822	LValue tempLV = lvalue;
823	// Drill down to the __block object if necessary.
824	if (capturedByInit) {
825	// We can use a simple GEP for this because it can't have been
826	// moved yet.
827	tempLV.setAddress(emitBlockByrefAddress(baseAddr: tempLV.getAddress(CGF&: *this),
828	V: cast<VarDecl>(Val: D),
829	/*follow*/ followForward: false));
830	}
831
832	auto ty =
833	cast<llvm::PointerType>(Val: tempLV.getAddress(CGF&: *this).getElementType());
834	llvm::Value *zero = CGM.getNullPointer(T: ty, QT: tempLV.getType());
835
836	// If __weak, we want to use a barrier under certain conditions.
837	if (lifetime == Qualifiers::OCL_Weak)
838	EmitARCInitWeak(addr: tempLV.getAddress(CGF&: *this), value: zero);
839
840	// Otherwise just do a simple store.
841	else
842	EmitStoreOfScalar(value: zero, lvalue: tempLV, /* isInitialization */ isInit: true);
843	}
844
845	// Emit the initializer.
846	llvm::Value *value = nullptr;
847
848	switch (lifetime) {
849	case Qualifiers::OCL_None:
850	llvm_unreachable("present but none");
851
852	case Qualifiers::OCL_Strong: {
853	if (!D || !isa<VarDecl>(Val: D) || !cast<VarDecl>(Val: D)->isARCPseudoStrong()) {
854	value = EmitARCRetainScalarExpr(expr: init);
855	break;
856	}
857	// If D is pseudo-strong, treat it like __unsafe_unretained here. This means
858	// that we omit the retain, and causes non-autoreleased return values to be
859	// immediately released.
860	[[fallthrough]];
861	}
862
863	case Qualifiers::OCL_ExplicitNone:
864	value = EmitARCUnsafeUnretainedScalarExpr(expr: init);
865	break;
866
867	case Qualifiers::OCL_Weak: {
868	// If it's not accessed by the initializer, try to emit the
869	// initialization with a copy or move.
870	if (!accessedByInit && tryEmitARCCopyWeakInit(CGF&: *this, destLV: lvalue, init)) {
871	return;
872	}
873
874	// No way to optimize a producing initializer into this. It's not
875	// worth optimizing for, because the value will immediately
876	// disappear in the common case.
877	value = EmitScalarExpr(E: init);
878
879	if (capturedByInit) drillIntoBlockVariable(CGF&: *this, lvalue, var: cast<VarDecl>(Val: D));
880	if (accessedByInit)
881	EmitARCStoreWeak(addr: lvalue.getAddress(CGF&: *this), value, /*ignored*/ true);
882	else
883	EmitARCInitWeak(addr: lvalue.getAddress(CGF&: *this), value);
884	return;
885	}
886
887	case Qualifiers::OCL_Autoreleasing:
888	value = EmitARCRetainAutoreleaseScalarExpr(expr: init);
889	break;
890	}
891
892	if (capturedByInit) drillIntoBlockVariable(CGF&: *this, lvalue, var: cast<VarDecl>(Val: D));
893
894	EmitNullabilityCheck(LHS: lvalue, RHS: value, Loc: init->getExprLoc());
895
896	// If the variable might have been accessed by its initializer, we
897	// might have to initialize with a barrier. We have to do this for
898	// both __weak and __strong, but __weak got filtered out above.
899	if (accessedByInit && lifetime == Qualifiers::OCL_Strong) {
900	llvm::Value *oldValue = EmitLoadOfScalar(lvalue, Loc: init->getExprLoc());
901	EmitStoreOfScalar(value, lvalue, /* isInitialization */ isInit: true);
902	EmitARCRelease(value: oldValue, precise: ARCImpreciseLifetime);
903	return;
904	}
905
906	EmitStoreOfScalar(value, lvalue, /* isInitialization */ isInit: true);
907	}
908
909	/// Decide whether we can emit the non-zero parts of the specified initializer
910	/// with equal or fewer than NumStores scalar stores.
911	static bool canEmitInitWithFewStoresAfterBZero(llvm::Constant *Init,
912	unsigned &NumStores) {
913	// Zero and Undef never requires any extra stores.
914	if (isa<llvm::ConstantAggregateZero>(Val: Init) ||
915	isa<llvm::ConstantPointerNull>(Val: Init) ||
916	isa<llvm::UndefValue>(Val: Init))
917	return true;
918	if (isa<llvm::ConstantInt>(Val: Init) || isa<llvm::ConstantFP>(Val: Init) ||
919	isa<llvm::ConstantVector>(Val: Init) || isa<llvm::BlockAddress>(Val: Init) ||
920	isa<llvm::ConstantExpr>(Val: Init))
921	return Init->isNullValue() || NumStores--;
922
923	// See if we can emit each element.
924	if (isa<llvm::ConstantArray>(Val: Init) || isa<llvm::ConstantStruct>(Val: Init)) {
925	for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
926	llvm::Constant *Elt = cast<llvm::Constant>(Val: Init->getOperand(i));
927	if (!canEmitInitWithFewStoresAfterBZero(Init: Elt, NumStores))
928	return false;
929	}
930	return true;
931	}
932
933	if (llvm::ConstantDataSequential *CDS =
934	dyn_cast<llvm::ConstantDataSequential>(Val: Init)) {
935	for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
936	llvm::Constant *Elt = CDS->getElementAsConstant(i);
937	if (!canEmitInitWithFewStoresAfterBZero(Init: Elt, NumStores))
938	return false;
939	}
940	return true;
941	}
942
943	// Anything else is hard and scary.
944	return false;
945	}
946
947	/// For inits that canEmitInitWithFewStoresAfterBZero returned true for, emit
948	/// the scalar stores that would be required.
949	static void emitStoresForInitAfterBZero(CodeGenModule &CGM,
950	llvm::Constant *Init, Address Loc,
951	bool isVolatile, CGBuilderTy &Builder,
952	bool IsAutoInit) {
953	assert(!Init->isNullValue() && !isa<llvm::UndefValue>(Init) &&
954	"called emitStoresForInitAfterBZero for zero or undef value.");
955
956	if (isa<llvm::ConstantInt>(Val: Init) || isa<llvm::ConstantFP>(Val: Init) ||
957	isa<llvm::ConstantVector>(Val: Init) || isa<llvm::BlockAddress>(Val: Init) ||
958	isa<llvm::ConstantExpr>(Val: Init)) {
959	auto *I = Builder.CreateStore(Val: Init, Addr: Loc, IsVolatile: isVolatile);
960	if (IsAutoInit)
961	I->addAnnotationMetadata(Annotation: "auto-init");
962	return;
963	}
964
965	if (llvm::ConstantDataSequential *CDS =
966	dyn_cast<llvm::ConstantDataSequential>(Val: Init)) {
967	for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
968	llvm::Constant *Elt = CDS->getElementAsConstant(i);
969
970	// If necessary, get a pointer to the element and emit it.
971	if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Val: Elt))
972	emitStoresForInitAfterBZero(
973	CGM, Init: Elt, Loc: Builder.CreateConstInBoundsGEP2_32(Addr: Loc, Idx0: 0, Idx1: i), isVolatile,
974	Builder, IsAutoInit);
975	}
976	return;
977	}
978
979	assert((isa<llvm::ConstantStruct>(Init) || isa<llvm::ConstantArray>(Init)) &&
980	"Unknown value type!");
981
982	for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
983	llvm::Constant *Elt = cast<llvm::Constant>(Val: Init->getOperand(i));
984
985	// If necessary, get a pointer to the element and emit it.
986	if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Val: Elt))
987	emitStoresForInitAfterBZero(CGM, Init: Elt,
988	Loc: Builder.CreateConstInBoundsGEP2_32(Addr: Loc, Idx0: 0, Idx1: i),
989	isVolatile, Builder, IsAutoInit);
990	}
991	}
992
993	/// Decide whether we should use bzero plus some stores to initialize a local
994	/// variable instead of using a memcpy from a constant global. It is beneficial
995	/// to use bzero if the global is all zeros, or mostly zeros and large.
996	static bool shouldUseBZeroPlusStoresToInitialize(llvm::Constant *Init,
997	uint64_t GlobalSize) {
998	// If a global is all zeros, always use a bzero.
999	if (isa<llvm::ConstantAggregateZero>(Val: Init)) return true;
1000
1001	// If a non-zero global is <= 32 bytes, always use a memcpy. If it is large,
1002	// do it if it will require 6 or fewer scalar stores.
1003	// TODO: Should budget depends on the size? Avoiding a large global warrants
1004	// plopping in more stores.
1005	unsigned StoreBudget = 6;
1006	uint64_t SizeLimit = 32;
1007
1008	return GlobalSize > SizeLimit &&
1009	canEmitInitWithFewStoresAfterBZero(Init, NumStores&: StoreBudget);
1010	}
1011
1012	/// Decide whether we should use memset to initialize a local variable instead
1013	/// of using a memcpy from a constant global. Assumes we've already decided to
1014	/// not user bzero.
1015	/// FIXME We could be more clever, as we are for bzero above, and generate
1016	/// memset followed by stores. It's unclear that's worth the effort.
1017	static llvm::Value *shouldUseMemSetToInitialize(llvm::Constant *Init,
1018	uint64_t GlobalSize,
1019	const llvm::DataLayout &DL) {
1020	uint64_t SizeLimit = 32;
1021	if (GlobalSize <= SizeLimit)
1022	return nullptr;
1023	return llvm::isBytewiseValue(V: Init, DL);
1024	}
1025
1026	/// Decide whether we want to split a constant structure or array store into a
1027	/// sequence of its fields' stores. This may cost us code size and compilation
1028	/// speed, but plays better with store optimizations.
1029	static bool shouldSplitConstantStore(CodeGenModule &CGM,
1030	uint64_t GlobalByteSize) {
1031	// Don't break things that occupy more than one cacheline.
1032	uint64_t ByteSizeLimit = 64;
1033	if (CGM.getCodeGenOpts().OptimizationLevel == 0)
1034	return false;
1035	if (GlobalByteSize <= ByteSizeLimit)
1036	return true;
1037	return false;
1038	}
1039
1040	enum class IsPattern { No, Yes };
1041
1042	/// Generate a constant filled with either a pattern or zeroes.
1043	static llvm::Constant *patternOrZeroFor(CodeGenModule &CGM, IsPattern isPattern,
1044	llvm::Type *Ty) {
1045	if (isPattern == IsPattern::Yes)
1046	return initializationPatternFor(CGM, Ty);
1047	else
1048	return llvm::Constant::getNullValue(Ty);
1049	}
1050
1051	static llvm::Constant *constWithPadding(CodeGenModule &CGM, IsPattern isPattern,
1052	llvm::Constant *constant);
1053
1054	/// Helper function for constWithPadding() to deal with padding in structures.
1055	static llvm::Constant *constStructWithPadding(CodeGenModule &CGM,
1056	IsPattern isPattern,
1057	llvm::StructType *STy,
1058	llvm::Constant *constant) {
1059	const llvm::DataLayout &DL = CGM.getDataLayout();
1060	const llvm::StructLayout *Layout = DL.getStructLayout(Ty: STy);
1061	llvm::Type *Int8Ty = llvm::IntegerType::getInt8Ty(C&: CGM.getLLVMContext());
1062	unsigned SizeSoFar = 0;
1063	SmallVector<llvm::Constant *, 8> Values;
1064	bool NestedIntact = true;
1065	for (unsigned i = 0, e = STy->getNumElements(); i != e; i++) {
1066	unsigned CurOff = Layout->getElementOffset(Idx: i);
1067	if (SizeSoFar < CurOff) {
1068	assert(!STy->isPacked());
1069	auto *PadTy = llvm::ArrayType::get(ElementType: Int8Ty, NumElements: CurOff - SizeSoFar);
1070	Values.push_back(Elt: patternOrZeroFor(CGM, isPattern, Ty: PadTy));
1071	}
1072	llvm::Constant *CurOp;
1073	if (constant->isZeroValue())
1074	CurOp = llvm::Constant::getNullValue(Ty: STy->getElementType(N: i));
1075	else
1076	CurOp = cast<llvm::Constant>(Val: constant->getAggregateElement(Elt: i));
1077	auto *NewOp = constWithPadding(CGM, isPattern, constant: CurOp);
1078	if (CurOp != NewOp)
1079	NestedIntact = false;
1080	Values.push_back(Elt: NewOp);
1081	SizeSoFar = CurOff + DL.getTypeAllocSize(Ty: CurOp->getType());
1082	}
1083	unsigned TotalSize = Layout->getSizeInBytes();
1084	if (SizeSoFar < TotalSize) {
1085	auto *PadTy = llvm::ArrayType::get(ElementType: Int8Ty, NumElements: TotalSize - SizeSoFar);
1086	Values.push_back(Elt: patternOrZeroFor(CGM, isPattern, Ty: PadTy));
1087	}
1088	if (NestedIntact && Values.size() == STy->getNumElements())
1089	return constant;
1090	return llvm::ConstantStruct::getAnon(V: Values, Packed: STy->isPacked());
1091	}
1092
1093	/// Replace all padding bytes in a given constant with either a pattern byte or
1094	/// 0x00.
1095	static llvm::Constant *constWithPadding(CodeGenModule &CGM, IsPattern isPattern,
1096	llvm::Constant *constant) {
1097	llvm::Type *OrigTy = constant->getType();
1098	if (const auto STy = dyn_cast<llvm::StructType>(Val: OrigTy))
1099	return constStructWithPadding(CGM, isPattern, STy, constant);
1100	if (auto *ArrayTy = dyn_cast<llvm::ArrayType>(Val: OrigTy)) {
1101	llvm::SmallVector<llvm::Constant *, 8> Values;
1102	uint64_t Size = ArrayTy->getNumElements();
1103	if (!Size)
1104	return constant;
1105	llvm::Type *ElemTy = ArrayTy->getElementType();
1106	bool ZeroInitializer = constant->isNullValue();
1107	llvm::Constant *OpValue, *PaddedOp;
1108	if (ZeroInitializer) {
1109	OpValue = llvm::Constant::getNullValue(Ty: ElemTy);
1110	PaddedOp = constWithPadding(CGM, isPattern, constant: OpValue);
1111	}
1112	for (unsigned Op = 0; Op != Size; ++Op) {
1113	if (!ZeroInitializer) {
1114	OpValue = constant->getAggregateElement(Elt: Op);
1115	PaddedOp = constWithPadding(CGM, isPattern, constant: OpValue);
1116	}
1117	Values.push_back(Elt: PaddedOp);
1118	}
1119	auto *NewElemTy = Values[0]->getType();
1120	if (NewElemTy == ElemTy)
1121	return constant;
1122	auto *NewArrayTy = llvm::ArrayType::get(ElementType: NewElemTy, NumElements: Size);
1123	return llvm::ConstantArray::get(T: NewArrayTy, V: Values);
1124	}
1125	// FIXME: Add handling for tail padding in vectors. Vectors don't
1126	// have padding between or inside elements, but the total amount of
1127	// data can be less than the allocated size.
1128	return constant;
1129	}
1130
1131	Address CodeGenModule::createUnnamedGlobalFrom(const VarDecl &D,
1132	llvm::Constant *Constant,
1133	CharUnits Align) {
1134	auto FunctionName = [&](const DeclContext *DC) -> std::string {
1135	if (const auto *FD = dyn_cast<FunctionDecl>(Val: DC)) {
1136	if (const auto *CC = dyn_cast<CXXConstructorDecl>(Val: FD))
1137	return CC->getNameAsString();
1138	if (const auto *CD = dyn_cast<CXXDestructorDecl>(Val: FD))
1139	return CD->getNameAsString();
1140	return std::string(getMangledName(GD: FD));
1141	} else if (const auto *OM = dyn_cast<ObjCMethodDecl>(Val: DC)) {
1142	return OM->getNameAsString();
1143	} else if (isa<BlockDecl>(Val: DC)) {
1144	return "<block>";
1145	} else if (isa<CapturedDecl>(Val: DC)) {
1146	return "<captured>";
1147	} else {
1148	llvm_unreachable("expected a function or method");
1149	}
1150	};
1151
1152	// Form a simple per-variable cache of these values in case we find we
1153	// want to reuse them.
1154	llvm::GlobalVariable *&CacheEntry = InitializerConstants[&D];
1155	if (!CacheEntry || CacheEntry->getInitializer() != Constant) {
1156	auto *Ty = Constant->getType();
1157	bool isConstant = true;
1158	llvm::GlobalVariable *InsertBefore = nullptr;
1159	unsigned AS =
1160	getContext().getTargetAddressSpace(AS: GetGlobalConstantAddressSpace());
1161	std::string Name;
1162	if (D.hasGlobalStorage())
1163	Name = getMangledName(GD: &D).str() + ".const";
1164	else if (const DeclContext *DC = D.getParentFunctionOrMethod())
1165	Name = ("__const." + FunctionName(DC) + "." + D.getName()).str();
1166	else
1167	llvm_unreachable("local variable has no parent function or method");
1168	llvm::GlobalVariable *GV = new llvm::GlobalVariable(
1169	getModule(), Ty, isConstant, llvm::GlobalValue::PrivateLinkage,
1170	Constant, Name, InsertBefore, llvm::GlobalValue::NotThreadLocal, AS);
1171	GV->setAlignment(Align.getAsAlign());
1172	GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1173	CacheEntry = GV;
1174	} else if (CacheEntry->getAlignment() < uint64_t(Align.getQuantity())) {
1175	CacheEntry->setAlignment(Align.getAsAlign());
1176	}
1177
1178	return Address(CacheEntry, CacheEntry->getValueType(), Align);
1179	}
1180
1181	static Address createUnnamedGlobalForMemcpyFrom(CodeGenModule &CGM,
1182	const VarDecl &D,
1183	CGBuilderTy &Builder,
1184	llvm::Constant *Constant,
1185	CharUnits Align) {
1186	Address SrcPtr = CGM.createUnnamedGlobalFrom(D, Constant, Align);
1187	return SrcPtr.withElementType(ElemTy: CGM.Int8Ty);
1188	}
1189
1190	static void emitStoresForConstant(CodeGenModule &CGM, const VarDecl &D,
1191	Address Loc, bool isVolatile,
1192	CGBuilderTy &Builder,
1193	llvm::Constant *constant, bool IsAutoInit) {
1194	auto *Ty = constant->getType();
1195	uint64_t ConstantSize = CGM.getDataLayout().getTypeAllocSize(Ty);
1196	if (!ConstantSize)
1197	return;
1198
1199	bool canDoSingleStore = Ty->isIntOrIntVectorTy() ||
1200	Ty->isPtrOrPtrVectorTy() || Ty->isFPOrFPVectorTy();
1201	if (canDoSingleStore) {
1202	auto *I = Builder.CreateStore(Val: constant, Addr: Loc, IsVolatile: isVolatile);
1203	if (IsAutoInit)
1204	I->addAnnotationMetadata(Annotation: "auto-init");
1205	return;
1206	}
1207
1208	auto *SizeVal = llvm::ConstantInt::get(Ty: CGM.IntPtrTy, V: ConstantSize);
1209
1210	// If the initializer is all or mostly the same, codegen with bzero / memset
1211	// then do a few stores afterward.
1212	if (shouldUseBZeroPlusStoresToInitialize(Init: constant, GlobalSize: ConstantSize)) {
1213	auto *I = Builder.CreateMemSet(Dest: Loc, Value: llvm::ConstantInt::get(Ty: CGM.Int8Ty, V: 0),
1214	Size: SizeVal, IsVolatile: isVolatile);
1215	if (IsAutoInit)
1216	I->addAnnotationMetadata(Annotation: "auto-init");
1217
1218	bool valueAlreadyCorrect =
1219	constant->isNullValue() || isa<llvm::UndefValue>(Val: constant);
1220	if (!valueAlreadyCorrect) {
1221	Loc = Loc.withElementType(ElemTy: Ty);
1222	emitStoresForInitAfterBZero(CGM, Init: constant, Loc, isVolatile, Builder,
1223	IsAutoInit);
1224	}
1225	return;
1226	}
1227
1228	// If the initializer is a repeated byte pattern, use memset.
1229	llvm::Value *Pattern =
1230	shouldUseMemSetToInitialize(Init: constant, GlobalSize: ConstantSize, DL: CGM.getDataLayout());
1231	if (Pattern) {
1232	uint64_t Value = 0x00;
1233	if (!isa<llvm::UndefValue>(Val: Pattern)) {
1234	const llvm::APInt &AP = cast<llvm::ConstantInt>(Val: Pattern)->getValue();
1235	assert(AP.getBitWidth() <= 8);
1236	Value = AP.getLimitedValue();
1237	}
1238	auto *I = Builder.CreateMemSet(
1239	Dest: Loc, Value: llvm::ConstantInt::get(Ty: CGM.Int8Ty, V: Value), Size: SizeVal, IsVolatile: isVolatile);
1240	if (IsAutoInit)
1241	I->addAnnotationMetadata(Annotation: "auto-init");
1242	return;
1243	}
1244
1245	// If the initializer is small or trivialAutoVarInit is set, use a handful of
1246	// stores.
1247	bool IsTrivialAutoVarInitPattern =
1248	CGM.getContext().getLangOpts().getTrivialAutoVarInit() ==
1249	LangOptions::TrivialAutoVarInitKind::Pattern;
1250	if (shouldSplitConstantStore(CGM, GlobalByteSize: ConstantSize)) {
1251	if (auto *STy = dyn_cast<llvm::StructType>(Val: Ty)) {
1252	if (STy == Loc.getElementType() ||
1253	(STy != Loc.getElementType() && IsTrivialAutoVarInitPattern)) {
1254	const llvm::StructLayout *Layout =
1255	CGM.getDataLayout().getStructLayout(Ty: STy);
1256	for (unsigned i = 0; i != constant->getNumOperands(); i++) {
1257	CharUnits CurOff =
1258	CharUnits::fromQuantity(Quantity: Layout->getElementOffset(Idx: i));
1259	Address EltPtr = Builder.CreateConstInBoundsByteGEP(
1260	Addr: Loc.withElementType(ElemTy: CGM.Int8Ty), Offset: CurOff);
1261	emitStoresForConstant(CGM, D, Loc: EltPtr, isVolatile, Builder,
1262	constant: constant->getAggregateElement(Elt: i), IsAutoInit);
1263	}
1264	return;
1265	}
1266	} else if (auto *ATy = dyn_cast<llvm::ArrayType>(Val: Ty)) {
1267	if (ATy == Loc.getElementType() ||
1268	(ATy != Loc.getElementType() && IsTrivialAutoVarInitPattern)) {
1269	for (unsigned i = 0; i != ATy->getNumElements(); i++) {
1270	Address EltPtr = Builder.CreateConstGEP(
1271	Addr: Loc.withElementType(ElemTy: ATy->getElementType()), Index: i);
1272	emitStoresForConstant(CGM, D, Loc: EltPtr, isVolatile, Builder,
1273	constant: constant->getAggregateElement(Elt: i), IsAutoInit);
1274	}
1275	return;
1276	}
1277	}
1278	}
1279
1280	// Copy from a global.
1281	auto *I =
1282	Builder.CreateMemCpy(Dest: Loc,
1283	Src: createUnnamedGlobalForMemcpyFrom(
1284	CGM, D, Builder, Constant: constant, Align: Loc.getAlignment()),
1285	Size: SizeVal, IsVolatile: isVolatile);
1286	if (IsAutoInit)
1287	I->addAnnotationMetadata(Annotation: "auto-init");
1288	}
1289
1290	static void emitStoresForZeroInit(CodeGenModule &CGM, const VarDecl &D,
1291	Address Loc, bool isVolatile,
1292	CGBuilderTy &Builder) {
1293	llvm::Type *ElTy = Loc.getElementType();
1294	llvm::Constant *constant =
1295	constWithPadding(CGM, isPattern: IsPattern::No, constant: llvm::Constant::getNullValue(Ty: ElTy));
1296	emitStoresForConstant(CGM, D, Loc, isVolatile, Builder, constant,
1297	/*IsAutoInit=*/true);
1298	}
1299
1300	static void emitStoresForPatternInit(CodeGenModule &CGM, const VarDecl &D,
1301	Address Loc, bool isVolatile,
1302	CGBuilderTy &Builder) {
1303	llvm::Type *ElTy = Loc.getElementType();
1304	llvm::Constant *constant = constWithPadding(
1305	CGM, isPattern: IsPattern::Yes, constant: initializationPatternFor(CGM, ElTy));
1306	assert(!isa<llvm::UndefValue>(constant));
1307	emitStoresForConstant(CGM, D, Loc, isVolatile, Builder, constant,
1308	/*IsAutoInit=*/true);
1309	}
1310
1311	static bool containsUndef(llvm::Constant *constant) {
1312	auto *Ty = constant->getType();
1313	if (isa<llvm::UndefValue>(Val: constant))
1314	return true;
1315	if (Ty->isStructTy() || Ty->isArrayTy() || Ty->isVectorTy())
1316	for (llvm::Use &Op : constant->operands())
1317	if (containsUndef(constant: cast<llvm::Constant>(Val&: Op)))
1318	return true;
1319	return false;
1320	}
1321
1322	static llvm::Constant *replaceUndef(CodeGenModule &CGM, IsPattern isPattern,
1323	llvm::Constant *constant) {
1324	auto *Ty = constant->getType();
1325	if (isa<llvm::UndefValue>(Val: constant))
1326	return patternOrZeroFor(CGM, isPattern, Ty);
1327	if (!(Ty->isStructTy() || Ty->isArrayTy() || Ty->isVectorTy()))
1328	return constant;
1329	if (!containsUndef(constant))
1330	return constant;
1331	llvm::SmallVector<llvm::Constant *, 8> Values(constant->getNumOperands());
1332	for (unsigned Op = 0, NumOp = constant->getNumOperands(); Op != NumOp; ++Op) {
1333	auto *OpValue = cast<llvm::Constant>(Val: constant->getOperand(i: Op));
1334	Values[Op] = replaceUndef(CGM, isPattern, constant: OpValue);
1335	}
1336	if (Ty->isStructTy())
1337	return llvm::ConstantStruct::get(T: cast<llvm::StructType>(Val: Ty), V: Values);
1338	if (Ty->isArrayTy())
1339	return llvm::ConstantArray::get(T: cast<llvm::ArrayType>(Val: Ty), V: Values);
1340	assert(Ty->isVectorTy());
1341	return llvm::ConstantVector::get(V: Values);
1342	}
1343
1344	/// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
1345	/// variable declaration with auto, register, or no storage class specifier.
1346	/// These turn into simple stack objects, or GlobalValues depending on target.
1347	void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
1348	AutoVarEmission emission = EmitAutoVarAlloca(var: D);
1349	EmitAutoVarInit(emission);
1350	EmitAutoVarCleanups(emission);
1351	}
1352
1353	/// Emit a lifetime.begin marker if some criteria are satisfied.
1354	/// \return a pointer to the temporary size Value if a marker was emitted, null
1355	/// otherwise
1356	llvm::Value *CodeGenFunction::EmitLifetimeStart(llvm::TypeSize Size,
1357	llvm::Value *Addr) {
1358	if (!ShouldEmitLifetimeMarkers)
1359	return nullptr;
1360
1361	assert(Addr->getType()->getPointerAddressSpace() ==
1362	CGM.getDataLayout().getAllocaAddrSpace() &&
1363	"Pointer should be in alloca address space");
1364	llvm::Value *SizeV = llvm::ConstantInt::get(
1365	Ty: Int64Ty, V: Size.isScalable() ? -1 : Size.getFixedValue());
1366	llvm::CallInst *C =
1367	Builder.CreateCall(Callee: CGM.getLLVMLifetimeStartFn(), Args: {SizeV, Addr});
1368	C->setDoesNotThrow();
1369	return SizeV;
1370	}
1371
1372	void CodeGenFunction::EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr) {
1373	assert(Addr->getType()->getPointerAddressSpace() ==
1374	CGM.getDataLayout().getAllocaAddrSpace() &&
1375	"Pointer should be in alloca address space");
1376	llvm::CallInst *C =
1377	Builder.CreateCall(Callee: CGM.getLLVMLifetimeEndFn(), Args: {Size, Addr});
1378	C->setDoesNotThrow();
1379	}
1380
1381	void CodeGenFunction::EmitAndRegisterVariableArrayDimensions(
1382	CGDebugInfo *DI, const VarDecl &D, bool EmitDebugInfo) {
1383	// For each dimension stores its QualType and corresponding
1384	// size-expression Value.
1385	SmallVector<CodeGenFunction::VlaSizePair, 4> Dimensions;
1386	SmallVector<const IdentifierInfo *, 4> VLAExprNames;
1387
1388	// Break down the array into individual dimensions.
1389	QualType Type1D = D.getType();
1390	while (getContext().getAsVariableArrayType(T: Type1D)) {
1391	auto VlaSize = getVLAElements1D(vla: Type1D);
1392	if (auto *C = dyn_cast<llvm::ConstantInt>(VlaSize.NumElts))
1393	Dimensions.emplace_back(C, Type1D.getUnqualifiedType());
1394	else {
1395	// Generate a locally unique name for the size expression.
1396	Twine Name = Twine("__vla_expr") + Twine(VLAExprCounter++);
1397	SmallString<12> Buffer;
1398	StringRef NameRef = Name.toStringRef(Out&: Buffer);
1399	auto &Ident = getContext().Idents.getOwn(Name: NameRef);
1400	VLAExprNames.push_back(Elt: &Ident);
1401	auto SizeExprAddr =
1402	CreateDefaultAlignTempAlloca(Ty: VlaSize.NumElts->getType(), Name: NameRef);
1403	Builder.CreateStore(Val: VlaSize.NumElts, Addr: SizeExprAddr);
1404	Dimensions.emplace_back(SizeExprAddr.getPointer(),
1405	Type1D.getUnqualifiedType());
1406	}
1407	Type1D = VlaSize.Type;
1408	}
1409
1410	if (!EmitDebugInfo)
1411	return;
1412
1413	// Register each dimension's size-expression with a DILocalVariable,
1414	// so that it can be used by CGDebugInfo when instantiating a DISubrange
1415	// to describe this array.
1416	unsigned NameIdx = 0;
1417	for (auto &VlaSize : Dimensions) {
1418	llvm::Metadata *MD;
1419	if (auto *C = dyn_cast<llvm::ConstantInt>(Val: VlaSize.NumElts))
1420	MD = llvm::ConstantAsMetadata::get(C);
1421	else {
1422	// Create an artificial VarDecl to generate debug info for.
1423	const IdentifierInfo *NameIdent = VLAExprNames[NameIdx++];
1424	auto QT = getContext().getIntTypeForBitwidth(
1425	DestWidth: SizeTy->getScalarSizeInBits(), Signed: false);
1426	auto *ArtificialDecl = VarDecl::Create(
1427	C&: getContext(), DC: const_cast<DeclContext *>(D.getDeclContext()),
1428	StartLoc: D.getLocation(), IdLoc: D.getLocation(), Id: NameIdent, T: QT,
1429	TInfo: getContext().CreateTypeSourceInfo(T: QT), S: SC_Auto);
1430	ArtificialDecl->setImplicit();
1431
1432	MD = DI->EmitDeclareOfAutoVariable(Decl: ArtificialDecl, AI: VlaSize.NumElts,
1433	Builder);
1434	}
1435	assert(MD && "No Size expression debug node created");
1436	DI->registerVLASizeExpression(Ty: VlaSize.Type, SizeExpr: MD);
1437	}
1438	}
1439
1440	/// EmitAutoVarAlloca - Emit the alloca and debug information for a
1441	/// local variable. Does not emit initialization or destruction.
1442	CodeGenFunction::AutoVarEmission
1443	CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
1444	QualType Ty = D.getType();
1445	assert(
1446	Ty.getAddressSpace() == LangAS::Default ||
1447	(Ty.getAddressSpace() == LangAS::opencl_private && getLangOpts().OpenCL));
1448
1449	AutoVarEmission emission(D);
1450
1451	bool isEscapingByRef = D.isEscapingByref();
1452	emission.IsEscapingByRef = isEscapingByRef;
1453
1454	CharUnits alignment = getContext().getDeclAlign(&D);
1455
1456	// If the type is variably-modified, emit all the VLA sizes for it.
1457	if (Ty->isVariablyModifiedType())
1458	EmitVariablyModifiedType(Ty);
1459
1460	auto *DI = getDebugInfo();
1461	bool EmitDebugInfo = DI && CGM.getCodeGenOpts().hasReducedDebugInfo();
1462
1463	Address address = Address::invalid();
1464	RawAddress AllocaAddr = RawAddress::invalid();
1465	Address OpenMPLocalAddr = Address::invalid();
1466	if (CGM.getLangOpts().OpenMPIRBuilder)
1467	OpenMPLocalAddr = OMPBuilderCBHelpers::getAddressOfLocalVariable(CGF&: *this, VD: &D);
1468	else
1469	OpenMPLocalAddr =
1470	getLangOpts().OpenMP
1471	? CGM.getOpenMPRuntime().getAddressOfLocalVariable(CGF&: *this, VD: &D)
1472	: Address::invalid();
1473
1474	bool NRVO = getLangOpts().ElideConstructors && D.isNRVOVariable();
1475
1476	if (getLangOpts().OpenMP && OpenMPLocalAddr.isValid()) {
1477	address = OpenMPLocalAddr;
1478	AllocaAddr = OpenMPLocalAddr;
1479	} else if (Ty->isConstantSizeType()) {
1480	// If this value is an array or struct with a statically determinable
1481	// constant initializer, there are optimizations we can do.
1482	//
1483	// TODO: We should constant-evaluate the initializer of any variable,
1484	// as long as it is initialized by a constant expression. Currently,
1485	// isConstantInitializer produces wrong answers for structs with
1486	// reference or bitfield members, and a few other cases, and checking
1487	// for POD-ness protects us from some of these.
1488	if (D.getInit() && (Ty->isArrayType() || Ty->isRecordType()) &&
1489	(D.isConstexpr() ||
1490	((Ty.isPODType(Context: getContext()) ||
1491	getContext().getBaseElementType(QT: Ty)->isObjCObjectPointerType()) &&
1492	D.getInit()->isConstantInitializer(Ctx&: getContext(), ForRef: false)))) {
1493
1494	// If the variable's a const type, and it's neither an NRVO
1495	// candidate nor a __block variable and has no mutable members,
1496	// emit it as a global instead.
1497	// Exception is if a variable is located in non-constant address space
1498	// in OpenCL.
1499	bool NeedsDtor =
1500	D.needsDestruction(Ctx: getContext()) == QualType::DK_cxx_destructor;
1501	if ((!getLangOpts().OpenCL ||
1502	Ty.getAddressSpace() == LangAS::opencl_constant) &&
1503	(CGM.getCodeGenOpts().MergeAllConstants && !NRVO &&
1504	!isEscapingByRef &&
1505	Ty.isConstantStorage(Ctx: getContext(), ExcludeCtor: true, ExcludeDtor: !NeedsDtor))) {
1506	EmitStaticVarDecl(D, Linkage: llvm::GlobalValue::InternalLinkage);
1507
1508	// Signal this condition to later callbacks.
1509	emission.Addr = Address::invalid();
1510	assert(emission.wasEmittedAsGlobal());
1511	return emission;
1512	}
1513
1514	// Otherwise, tell the initialization code that we're in this case.
1515	emission.IsConstantAggregate = true;
1516	}
1517
1518	// A normal fixed sized variable becomes an alloca in the entry block,
1519	// unless:
1520	// - it's an NRVO variable.
1521	// - we are compiling OpenMP and it's an OpenMP local variable.
1522	if (NRVO) {
1523	// The named return value optimization: allocate this variable in the
1524	// return slot, so that we can elide the copy when returning this
1525	// variable (C++0x [class.copy]p34).
1526	address = ReturnValue;
1527	AllocaAddr =
1528	RawAddress(ReturnValue.emitRawPointer(CGF&: *this),
1529	ReturnValue.getElementType(), ReturnValue.getAlignment());
1530	;
1531
1532	if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
1533	const auto *RD = RecordTy->getDecl();
1534	const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD);
1535	if ((CXXRD && !CXXRD->hasTrivialDestructor()) ||
1536	RD->isNonTrivialToPrimitiveDestroy()) {
1537	// Create a flag that is used to indicate when the NRVO was applied
1538	// to this variable. Set it to zero to indicate that NRVO was not
1539	// applied.
1540	llvm::Value *Zero = Builder.getFalse();
1541	RawAddress NRVOFlag =
1542	CreateTempAlloca(Ty: Zero->getType(), align: CharUnits::One(), Name: "nrvo");
1543	EnsureInsertPoint();
1544	Builder.CreateStore(Val: Zero, Addr: NRVOFlag);
1545
1546	// Record the NRVO flag for this variable.
1547	NRVOFlags[&D] = NRVOFlag.getPointer();
1548	emission.NRVOFlag = NRVOFlag.getPointer();
1549	}
1550	}
1551	} else {
1552	CharUnits allocaAlignment;
1553	llvm::Type *allocaTy;
1554	if (isEscapingByRef) {
1555	auto &byrefInfo = getBlockByrefInfo(var: &D);
1556	allocaTy = byrefInfo.Type;
1557	allocaAlignment = byrefInfo.ByrefAlignment;
1558	} else {
1559	allocaTy = ConvertTypeForMem(T: Ty);
1560	allocaAlignment = alignment;
1561	}
1562
1563	// Create the alloca. Note that we set the name separately from
1564	// building the instruction so that it's there even in no-asserts
1565	// builds.
1566	address = CreateTempAlloca(allocaTy, allocaAlignment, D.getName(),
1567	/*ArraySize=*/nullptr, &AllocaAddr);
1568
1569	// Don't emit lifetime markers for MSVC catch parameters. The lifetime of
1570	// the catch parameter starts in the catchpad instruction, and we can't
1571	// insert code in those basic blocks.
1572	bool IsMSCatchParam =
1573	D.isExceptionVariable() && getTarget().getCXXABI().isMicrosoft();
1574
1575	// Emit a lifetime intrinsic if meaningful. There's no point in doing this
1576	// if we don't have a valid insertion point (?).
1577	if (HaveInsertPoint() && !IsMSCatchParam) {
1578	// If there's a jump into the lifetime of this variable, its lifetime
1579	// gets broken up into several regions in IR, which requires more work
1580	// to handle correctly. For now, just omit the intrinsics; this is a
1581	// rare case, and it's better to just be conservatively correct.
1582	// PR28267.
1583	//
1584	// We have to do this in all language modes if there's a jump past the
1585	// declaration. We also have to do it in C if there's a jump to an
1586	// earlier point in the current block because non-VLA lifetimes begin as
1587	// soon as the containing block is entered, not when its variables
1588	// actually come into scope; suppressing the lifetime annotations
1589	// completely in this case is unnecessarily pessimistic, but again, this
1590	// is rare.
1591	if (!Bypasses.IsBypassed(D: &D) &&
1592	!(!getLangOpts().CPlusPlus && hasLabelBeenSeenInCurrentScope())) {
1593	llvm::TypeSize Size = CGM.getDataLayout().getTypeAllocSize(Ty: allocaTy);
1594	emission.SizeForLifetimeMarkers =
1595	EmitLifetimeStart(Size, Addr: AllocaAddr.getPointer());
1596	}
1597	} else {
1598	assert(!emission.useLifetimeMarkers());
1599	}
1600	}
1601	} else {
1602	EnsureInsertPoint();
1603
1604	// Delayed globalization for variable length declarations. This ensures that
1605	// the expression representing the length has been emitted and can be used
1606	// by the definition of the VLA. Since this is an escaped declaration, in
1607	// OpenMP we have to use a call to __kmpc_alloc_shared(). The matching
1608	// deallocation call to __kmpc_free_shared() is emitted later.
1609	bool VarAllocated = false;
1610	if (getLangOpts().OpenMPIsTargetDevice) {
1611	auto &RT = CGM.getOpenMPRuntime();
1612	if (RT.isDelayedVariableLengthDecl(CGF&: *this, VD: &D)) {
1613	// Emit call to __kmpc_alloc_shared() instead of the alloca.
1614	std::pair<llvm::Value *, llvm::Value *> AddrSizePair =
1615	RT.getKmpcAllocShared(CGF&: *this, VD: &D);
1616
1617	// Save the address of the allocation:
1618	LValue Base = MakeAddrLValue(AddrSizePair.first, D.getType(),
1619	CGM.getContext().getDeclAlign(&D),
1620	AlignmentSource::Decl);
1621	address = Base.getAddress(CGF&: *this);
1622
1623	// Push a cleanup block to emit the call to __kmpc_free_shared in the
1624	// appropriate location at the end of the scope of the
1625	// __kmpc_alloc_shared functions:
1626	pushKmpcAllocFree(Kind: NormalCleanup, AddrSizePair);
1627
1628	// Mark variable as allocated:
1629	VarAllocated = true;
1630	}
1631	}
1632
1633	if (!VarAllocated) {
1634	if (!DidCallStackSave) {
1635	// Save the stack.
1636	Address Stack =
1637	CreateDefaultAlignTempAlloca(Ty: AllocaInt8PtrTy, Name: "saved_stack");
1638
1639	llvm::Value *V = Builder.CreateStackSave();
1640	assert(V->getType() == AllocaInt8PtrTy);
1641	Builder.CreateStore(Val: V, Addr: Stack);
1642
1643	DidCallStackSave = true;
1644
1645	// Push a cleanup block and restore the stack there.
1646	// FIXME: in general circumstances, this should be an EH cleanup.
1647	pushStackRestore(kind: NormalCleanup, SPMem: Stack);
1648	}
1649
1650	auto VlaSize = getVLASize(vla: Ty);
1651	llvm::Type *llvmTy = ConvertTypeForMem(T: VlaSize.Type);
1652
1653	// Allocate memory for the array.
1654	address = CreateTempAlloca(llvmTy, alignment, "vla", VlaSize.NumElts,
1655	&AllocaAddr);
1656	}
1657
1658	// If we have debug info enabled, properly describe the VLA dimensions for
1659	// this type by registering the vla size expression for each of the
1660	// dimensions.
1661	EmitAndRegisterVariableArrayDimensions(DI, D, EmitDebugInfo);
1662	}
1663
1664	setAddrOfLocalVar(VD: &D, Addr: address);
1665	emission.Addr = address;
1666	emission.AllocaAddr = AllocaAddr;
1667
1668	// Emit debug info for local var declaration.
1669	if (EmitDebugInfo && HaveInsertPoint()) {
1670	Address DebugAddr = address;
1671	bool UsePointerValue = NRVO && ReturnValuePointer.isValid();
1672	DI->setLocation(D.getLocation());
1673
1674	// If NRVO, use a pointer to the return address.
1675	if (UsePointerValue) {
1676	DebugAddr = ReturnValuePointer;
1677	AllocaAddr = ReturnValuePointer;
1678	}
1679	(void)DI->EmitDeclareOfAutoVariable(Decl: &D, AI: AllocaAddr.getPointer(), Builder,
1680	UsePointerValue);
1681	}
1682
1683	if (D.hasAttr<AnnotateAttr>() && HaveInsertPoint())
1684	EmitVarAnnotations(D: &D, V: address.emitRawPointer(CGF&: *this));
1685
1686	// Make sure we call @llvm.lifetime.end.
1687	if (emission.useLifetimeMarkers())
1688	EHStack.pushCleanup<CallLifetimeEnd>(Kind: NormalEHLifetimeMarker,
1689	A: emission.getOriginalAllocatedAddress(),
1690	A: emission.getSizeForLifetimeMarkers());
1691
1692	return emission;
1693	}
1694
1695	static bool isCapturedBy(const VarDecl &, const Expr *);
1696
1697	/// Determines whether the given __block variable is potentially
1698	/// captured by the given statement.
1699	static bool isCapturedBy(const VarDecl &Var, const Stmt *S) {
1700	if (const Expr *E = dyn_cast<Expr>(Val: S))
1701	return isCapturedBy(Var, E);
1702	for (const Stmt *SubStmt : S->children())
1703	if (isCapturedBy(Var, S: SubStmt))
1704	return true;
1705	return false;
1706	}
1707
1708	/// Determines whether the given __block variable is potentially
1709	/// captured by the given expression.
1710	static bool isCapturedBy(const VarDecl &Var, const Expr *E) {
1711	// Skip the most common kinds of expressions that make
1712	// hierarchy-walking expensive.
1713	E = E->IgnoreParenCasts();
1714
1715	if (const BlockExpr *BE = dyn_cast<BlockExpr>(Val: E)) {
1716	const BlockDecl *Block = BE->getBlockDecl();
1717	for (const auto &I : Block->captures()) {
1718	if (I.getVariable() == &Var)
1719	return true;
1720	}
1721
1722	// No need to walk into the subexpressions.
1723	return false;
1724	}
1725
1726	if (const StmtExpr *SE = dyn_cast<StmtExpr>(Val: E)) {
1727	const CompoundStmt *CS = SE->getSubStmt();
1728	for (const auto *BI : CS->body())
1729	if (const auto *BIE = dyn_cast<Expr>(Val: BI)) {
1730	if (isCapturedBy(Var, E: BIE))
1731	return true;
1732	}
1733	else if (const auto *DS = dyn_cast<DeclStmt>(Val: BI)) {
1734	// special case declarations
1735	for (const auto *I : DS->decls()) {
1736	if (const auto *VD = dyn_cast<VarDecl>(Val: (I))) {
1737	const Expr *Init = VD->getInit();
1738	if (Init && isCapturedBy(Var, E: Init))
1739	return true;
1740	}
1741	}
1742	}
1743	else
1744	// FIXME. Make safe assumption assuming arbitrary statements cause capturing.
1745	// Later, provide code to poke into statements for capture analysis.
1746	return true;
1747	return false;
1748	}
1749
1750	for (const Stmt *SubStmt : E->children())
1751	if (isCapturedBy(Var, SubStmt))
1752	return true;
1753
1754	return false;
1755	}
1756
1757	/// Determine whether the given initializer is trivial in the sense
1758	/// that it requires no code to be generated.
1759	bool CodeGenFunction::isTrivialInitializer(const Expr *Init) {
1760	if (!Init)
1761	return true;
1762
1763	if (const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Val: Init))
1764	if (CXXConstructorDecl *Constructor = Construct->getConstructor())
1765	if (Constructor->isTrivial() &&
1766	Constructor->isDefaultConstructor() &&
1767	!Construct->requiresZeroInitialization())
1768	return true;
1769
1770	return false;
1771	}
1772
1773	void CodeGenFunction::emitZeroOrPatternForAutoVarInit(QualType type,
1774	const VarDecl &D,
1775	Address Loc) {
1776	auto trivialAutoVarInit = getContext().getLangOpts().getTrivialAutoVarInit();
1777	auto trivialAutoVarInitMaxSize =
1778	getContext().getLangOpts().TrivialAutoVarInitMaxSize;
1779	CharUnits Size = getContext().getTypeSizeInChars(T: type);
1780	bool isVolatile = type.isVolatileQualified();
1781	if (!Size.isZero()) {
1782	// We skip auto-init variables by their alloc size. Take this as an example:
1783	// "struct Foo {int x; char buff[1024];}" Assume the max-size flag is 1023.
1784	// All Foo type variables will be skipped. Ideally, we only skip the buff
1785	// array and still auto-init X in this example.
1786	// TODO: Improve the size filtering to by member size.
1787	auto allocSize = CGM.getDataLayout().getTypeAllocSize(Ty: Loc.getElementType());
1788	switch (trivialAutoVarInit) {
1789	case LangOptions::TrivialAutoVarInitKind::Uninitialized:
1790	llvm_unreachable("Uninitialized handled by caller");
1791	case LangOptions::TrivialAutoVarInitKind::Zero:
1792	if (CGM.stopAutoInit())
1793	return;
1794	if (trivialAutoVarInitMaxSize > 0 &&
1795	allocSize > trivialAutoVarInitMaxSize)
1796	return;
1797	emitStoresForZeroInit(CGM, D, Loc, isVolatile, Builder);
1798	break;
1799	case LangOptions::TrivialAutoVarInitKind::Pattern:
1800	if (CGM.stopAutoInit())
1801	return;
1802	if (trivialAutoVarInitMaxSize > 0 &&
1803	allocSize > trivialAutoVarInitMaxSize)
1804	return;
1805	emitStoresForPatternInit(CGM, D, Loc, isVolatile, Builder);
1806	break;
1807	}
1808	return;
1809	}
1810
1811	// VLAs look zero-sized to getTypeInfo. We can't emit constant stores to
1812	// them, so emit a memcpy with the VLA size to initialize each element.
1813	// Technically zero-sized or negative-sized VLAs are undefined, and UBSan
1814	// will catch that code, but there exists code which generates zero-sized
1815	// VLAs. Be nice and initialize whatever they requested.
1816	const auto *VlaType = getContext().getAsVariableArrayType(T: type);
1817	if (!VlaType)
1818	return;
1819	auto VlaSize = getVLASize(vla: VlaType);
1820	auto SizeVal = VlaSize.NumElts;
1821	CharUnits EltSize = getContext().getTypeSizeInChars(VlaSize.Type);
1822	switch (trivialAutoVarInit) {
1823	case LangOptions::TrivialAutoVarInitKind::Uninitialized:
1824	llvm_unreachable("Uninitialized handled by caller");
1825
1826	case LangOptions::TrivialAutoVarInitKind::Zero: {
1827	if (CGM.stopAutoInit())
1828	return;
1829	if (!EltSize.isOne())
1830	SizeVal = Builder.CreateNUWMul(LHS: SizeVal, RHS: CGM.getSize(numChars: EltSize));
1831	auto *I = Builder.CreateMemSet(Dest: Loc, Value: llvm::ConstantInt::get(Ty: Int8Ty, V: 0),
1832	Size: SizeVal, IsVolatile: isVolatile);
1833	I->addAnnotationMetadata(Annotation: "auto-init");
1834	break;
1835	}
1836
1837	case LangOptions::TrivialAutoVarInitKind::Pattern: {
1838	if (CGM.stopAutoInit())
1839	return;
1840	llvm::Type *ElTy = Loc.getElementType();
1841	llvm::Constant *Constant = constWithPadding(
1842	CGM, isPattern: IsPattern::Yes, constant: initializationPatternFor(CGM, ElTy));
1843	CharUnits ConstantAlign = getContext().getTypeAlignInChars(VlaSize.Type);
1844	llvm::BasicBlock *SetupBB = createBasicBlock(name: "vla-setup.loop");
1845	llvm::BasicBlock *LoopBB = createBasicBlock(name: "vla-init.loop");
1846	llvm::BasicBlock *ContBB = createBasicBlock(name: "vla-init.cont");
1847	llvm::Value *IsZeroSizedVLA = Builder.CreateICmpEQ(
1848	LHS: SizeVal, RHS: llvm::ConstantInt::get(Ty: SizeVal->getType(), V: 0),
1849	Name: "vla.iszerosized");
1850	Builder.CreateCondBr(Cond: IsZeroSizedVLA, True: ContBB, False: SetupBB);
1851	EmitBlock(BB: SetupBB);
1852	if (!EltSize.isOne())
1853	SizeVal = Builder.CreateNUWMul(LHS: SizeVal, RHS: CGM.getSize(numChars: EltSize));
1854	llvm::Value *BaseSizeInChars =
1855	llvm::ConstantInt::get(Ty: IntPtrTy, V: EltSize.getQuantity());
1856	Address Begin = Loc.withElementType(ElemTy: Int8Ty);
1857	llvm::Value *End = Builder.CreateInBoundsGEP(Ty: Begin.getElementType(),
1858	Ptr: Begin.emitRawPointer(CGF&: *this),
1859	IdxList: SizeVal, Name: "vla.end");
1860	llvm::BasicBlock *OriginBB = Builder.GetInsertBlock();
1861	EmitBlock(BB: LoopBB);
1862	llvm::PHINode *Cur = Builder.CreatePHI(Ty: Begin.getType(), NumReservedValues: 2, Name: "vla.cur");
1863	Cur->addIncoming(V: Begin.emitRawPointer(CGF&: *this), BB: OriginBB);
1864	CharUnits CurAlign = Loc.getAlignment().alignmentOfArrayElement(elementSize: EltSize);
1865	auto *I =
1866	Builder.CreateMemCpy(Dest: Address(Cur, Int8Ty, CurAlign),
1867	Src: createUnnamedGlobalForMemcpyFrom(
1868	CGM, D, Builder, Constant, Align: ConstantAlign),
1869	Size: BaseSizeInChars, IsVolatile: isVolatile);
1870	I->addAnnotationMetadata("auto-init");
1871	llvm::Value *Next =
1872	Builder.CreateInBoundsGEP(Ty: Int8Ty, Ptr: Cur, IdxList: BaseSizeInChars, Name: "vla.next");
1873	llvm::Value *Done = Builder.CreateICmpEQ(LHS: Next, RHS: End, Name: "vla-init.isdone");
1874	Builder.CreateCondBr(Cond: Done, True: ContBB, False: LoopBB);
1875	Cur->addIncoming(V: Next, BB: LoopBB);
1876	EmitBlock(BB: ContBB);
1877	} break;
1878	}
1879	}
1880
1881	void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
1882	assert(emission.Variable && "emission was not valid!");
1883
1884	// If this was emitted as a global constant, we're done.
1885	if (emission.wasEmittedAsGlobal()) return;
1886
1887	const VarDecl &D = *emission.Variable;
1888	auto DL = ApplyDebugLocation::CreateDefaultArtificial(CGF&: *this, TemporaryLocation: D.getLocation());
1889	QualType type = D.getType();
1890
1891	// If this local has an initializer, emit it now.
1892	const Expr *Init = D.getInit();
1893
1894	// If we are at an unreachable point, we don't need to emit the initializer
1895	// unless it contains a label.
1896	if (!HaveInsertPoint()) {
1897	if (!Init || !ContainsLabel(Init)) return;
1898	EnsureInsertPoint();
1899	}
1900
1901	// Initialize the structure of a __block variable.
1902	if (emission.IsEscapingByRef)
1903	emitByrefStructureInit(emission);
1904
1905	// Initialize the variable here if it doesn't have a initializer and it is a
1906	// C struct that is non-trivial to initialize or an array containing such a
1907	// struct.
1908	if (!Init &&
1909	type.isNonTrivialToPrimitiveDefaultInitialize() ==
1910	QualType::PDIK_Struct) {
1911	LValue Dst = MakeAddrLValue(Addr: emission.getAllocatedAddress(), T: type);
1912	if (emission.IsEscapingByRef)
1913	drillIntoBlockVariable(CGF&: *this, lvalue&: Dst, var: &D);
1914	defaultInitNonTrivialCStructVar(Dst);
1915	return;
1916	}
1917
1918	// Check whether this is a byref variable that's potentially
1919	// captured and moved by its own initializer. If so, we'll need to
1920	// emit the initializer first, then copy into the variable.
1921	bool capturedByInit =
1922	Init && emission.IsEscapingByRef && isCapturedBy(Var: D, E: Init);
1923
1924	bool locIsByrefHeader = !capturedByInit;
1925	const Address Loc =
1926	locIsByrefHeader ? emission.getObjectAddress(CGF&: *this) : emission.Addr;
1927
1928	// Note: constexpr already initializes everything correctly.
1929	LangOptions::TrivialAutoVarInitKind trivialAutoVarInit =
1930	(D.isConstexpr()
1931	? LangOptions::TrivialAutoVarInitKind::Uninitialized
1932	: (D.getAttr<UninitializedAttr>()
1933	? LangOptions::TrivialAutoVarInitKind::Uninitialized
1934	: getContext().getLangOpts().getTrivialAutoVarInit()));
1935
1936	auto initializeWhatIsTechnicallyUninitialized = [&](Address Loc) {
1937	if (trivialAutoVarInit ==
1938	LangOptions::TrivialAutoVarInitKind::Uninitialized)
1939	return;
1940
1941	// Only initialize a __block's storage: we always initialize the header.
1942	if (emission.IsEscapingByRef && !locIsByrefHeader)
1943	Loc = emitBlockByrefAddress(baseAddr: Loc, V: &D, /*follow=*/followForward: false);
1944
1945	return emitZeroOrPatternForAutoVarInit(type, D, Loc);
1946	};
1947
1948	if (isTrivialInitializer(Init))
1949	return initializeWhatIsTechnicallyUninitialized(Loc);
1950
1951	llvm::Constant *constant = nullptr;
1952	if (emission.IsConstantAggregate ||
1953	D.mightBeUsableInConstantExpressions(C: getContext())) {
1954	assert(!capturedByInit && "constant init contains a capturing block?");
1955	constant = ConstantEmitter(*this).tryEmitAbstractForInitializer(D);
1956	if (constant && !constant->isZeroValue() &&
1957	(trivialAutoVarInit !=
1958	LangOptions::TrivialAutoVarInitKind::Uninitialized)) {
1959	IsPattern isPattern =
1960	(trivialAutoVarInit == LangOptions::TrivialAutoVarInitKind::Pattern)
1961	? IsPattern::Yes
1962	: IsPattern::No;
1963	// C guarantees that brace-init with fewer initializers than members in
1964	// the aggregate will initialize the rest of the aggregate as-if it were
1965	// static initialization. In turn static initialization guarantees that
1966	// padding is initialized to zero bits. We could instead pattern-init if D
1967	// has any ImplicitValueInitExpr, but that seems to be unintuitive
1968	// behavior.
1969	constant = constWithPadding(CGM, isPattern: IsPattern::No,
1970	constant: replaceUndef(CGM, isPattern, constant));
1971	}
1972	}
1973
1974	if (!constant) {
1975	initializeWhatIsTechnicallyUninitialized(Loc);
1976	LValue lv = MakeAddrLValue(Addr: Loc, T: type);
1977	lv.setNonGC(true);
1978	return EmitExprAsInit(Init, &D, lv, capturedByInit);
1979	}
1980
1981	if (!emission.IsConstantAggregate) {
1982	// For simple scalar/complex initialization, store the value directly.
1983	LValue lv = MakeAddrLValue(Addr: Loc, T: type);
1984	lv.setNonGC(true);
1985	return EmitStoreThroughLValue(Src: RValue::get(V: constant), Dst: lv, isInit: true);
1986	}
1987
1988	emitStoresForConstant(CGM, D, Loc: Loc.withElementType(ElemTy: CGM.Int8Ty),
1989	isVolatile: type.isVolatileQualified(), Builder, constant,
1990	/*IsAutoInit=*/false);
1991	}
1992
1993	/// Emit an expression as an initializer for an object (variable, field, etc.)
1994	/// at the given location. The expression is not necessarily the normal
1995	/// initializer for the object, and the address is not necessarily
1996	/// its normal location.
1997	///
1998	/// \param init the initializing expression
1999	/// \param D the object to act as if we're initializing
2000	/// \param lvalue the lvalue to initialize
2001	/// \param capturedByInit true if \p D is a __block variable
2002	/// whose address is potentially changed by the initializer
2003	void CodeGenFunction::EmitExprAsInit(const Expr *init, const ValueDecl *D,
2004	LValue lvalue, bool capturedByInit) {
2005	QualType type = D->getType();
2006
2007	if (type->isReferenceType()) {
2008	RValue rvalue = EmitReferenceBindingToExpr(E: init);
2009	if (capturedByInit)
2010	drillIntoBlockVariable(CGF&: *this, lvalue, var: cast<VarDecl>(Val: D));
2011	EmitStoreThroughLValue(Src: rvalue, Dst: lvalue, isInit: true);
2012	return;
2013	}
2014	switch (getEvaluationKind(T: type)) {
2015	case TEK_Scalar:
2016	EmitScalarInit(init, D, lvalue, capturedByInit);
2017	return;
2018	case TEK_Complex: {
2019	ComplexPairTy complex = EmitComplexExpr(E: init);
2020	if (capturedByInit)
2021	drillIntoBlockVariable(CGF&: *this, lvalue, var: cast<VarDecl>(Val: D));
2022	EmitStoreOfComplex(V: complex, dest: lvalue, /*init*/ isInit: true);
2023	return;
2024	}
2025	case TEK_Aggregate:
2026	if (type->isAtomicType()) {
2027	EmitAtomicInit(E: const_cast<Expr*>(init), lvalue);
2028	} else {
2029	AggValueSlot::Overlap_t Overlap = AggValueSlot::MayOverlap;
2030	if (isa<VarDecl>(Val: D))
2031	Overlap = AggValueSlot::DoesNotOverlap;
2032	else if (auto *FD = dyn_cast<FieldDecl>(Val: D))
2033	Overlap = getOverlapForFieldInit(FD);
2034	// TODO: how can we delay here if D is captured by its initializer?
2035	EmitAggExpr(E: init, AS: AggValueSlot::forLValue(
2036	LV: lvalue, CGF&: *this, isDestructed: AggValueSlot::IsDestructed,
2037	needsGC: AggValueSlot::DoesNotNeedGCBarriers,
2038	isAliased: AggValueSlot::IsNotAliased, mayOverlap: Overlap));
2039	}
2040	return;
2041	}
2042	llvm_unreachable("bad evaluation kind");
2043	}
2044
2045	/// Enter a destroy cleanup for the given local variable.
2046	void CodeGenFunction::emitAutoVarTypeCleanup(
2047	const CodeGenFunction::AutoVarEmission &emission,
2048	QualType::DestructionKind dtorKind) {
2049	assert(dtorKind != QualType::DK_none);
2050
2051	// Note that for __block variables, we want to destroy the
2052	// original stack object, not the possibly forwarded object.
2053	Address addr = emission.getObjectAddress(CGF&: *this);
2054
2055	const VarDecl *var = emission.Variable;
2056	QualType type = var->getType();
2057
2058	CleanupKind cleanupKind = NormalAndEHCleanup;
2059	CodeGenFunction::Destroyer *destroyer = nullptr;
2060
2061	switch (dtorKind) {
2062	case QualType::DK_none:
2063	llvm_unreachable("no cleanup for trivially-destructible variable");
2064
2065	case QualType::DK_cxx_destructor:
2066	// If there's an NRVO flag on the emission, we need a different
2067	// cleanup.
2068	if (emission.NRVOFlag) {
2069	assert(!type->isArrayType());
2070	CXXDestructorDecl *dtor = type->getAsCXXRecordDecl()->getDestructor();
2071	EHStack.pushCleanup<DestroyNRVOVariableCXX>(Kind: cleanupKind, A: addr, A: type, A: dtor,
2072	A: emission.NRVOFlag);
2073	return;
2074	}
2075	break;
2076
2077	case QualType::DK_objc_strong_lifetime:
2078	// Suppress cleanups for pseudo-strong variables.
2079	if (var->isARCPseudoStrong()) return;
2080
2081	// Otherwise, consider whether to use an EH cleanup or not.
2082	cleanupKind = getARCCleanupKind();
2083
2084	// Use the imprecise destroyer by default.
2085	if (!var->hasAttr<ObjCPreciseLifetimeAttr>())
2086	destroyer = CodeGenFunction::destroyARCStrongImprecise;
2087	break;
2088
2089	case QualType::DK_objc_weak_lifetime:
2090	break;
2091
2092	case QualType::DK_nontrivial_c_struct:
2093	destroyer = CodeGenFunction::destroyNonTrivialCStruct;
2094	if (emission.NRVOFlag) {
2095	assert(!type->isArrayType());
2096	EHStack.pushCleanup<DestroyNRVOVariableC>(Kind: cleanupKind, A: addr,
2097	A: emission.NRVOFlag, A: type);
2098	return;
2099	}
2100	break;
2101	}
2102
2103	// If we haven't chosen a more specific destroyer, use the default.
2104	if (!destroyer) destroyer = getDestroyer(destructionKind: dtorKind);
2105
2106	// Use an EH cleanup in array destructors iff the destructor itself
2107	// is being pushed as an EH cleanup.
2108	bool useEHCleanup = (cleanupKind & EHCleanup);
2109	EHStack.pushCleanup<DestroyObject>(Kind: cleanupKind, A: addr, A: type, A: destroyer,
2110	A: useEHCleanup);
2111	}
2112
2113	void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
2114	assert(emission.Variable && "emission was not valid!");
2115
2116	// If this was emitted as a global constant, we're done.
2117	if (emission.wasEmittedAsGlobal()) return;
2118
2119	// If we don't have an insertion point, we're done. Sema prevents
2120	// us from jumping into any of these scopes anyway.
2121	if (!HaveInsertPoint()) return;
2122
2123	const VarDecl &D = *emission.Variable;
2124
2125	// Check the type for a cleanup.
2126	if (QualType::DestructionKind dtorKind = D.needsDestruction(Ctx: getContext()))
2127	emitAutoVarTypeCleanup(emission, dtorKind);
2128
2129	// In GC mode, honor objc_precise_lifetime.
2130	if (getLangOpts().getGC() != LangOptions::NonGC &&
2131	D.hasAttr<ObjCPreciseLifetimeAttr>()) {
2132	EHStack.pushCleanup<ExtendGCLifetime>(Kind: NormalCleanup, A: &D);
2133	}
2134
2135	// Handle the cleanup attribute.
2136	if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
2137	const FunctionDecl *FD = CA->getFunctionDecl();
2138
2139	llvm::Constant *F = CGM.GetAddrOfFunction(GD: FD);
2140	assert(F && "Could not find function!");
2141
2142	const CGFunctionInfo &Info = CGM.getTypes().arrangeFunctionDeclaration(FD);
2143	EHStack.pushCleanup<CallCleanupFunction>(Kind: NormalAndEHCleanup, A: F, A: &Info, A: &D);
2144	}
2145
2146	// If this is a block variable, call _Block_object_destroy
2147	// (on the unforwarded address). Don't enter this cleanup if we're in pure-GC
2148	// mode.
2149	if (emission.IsEscapingByRef &&
2150	CGM.getLangOpts().getGC() != LangOptions::GCOnly) {
2151	BlockFieldFlags Flags = BLOCK_FIELD_IS_BYREF;
2152	if (emission.Variable->getType().isObjCGCWeak())
2153	Flags |= BLOCK_FIELD_IS_WEAK;
2154	enterByrefCleanup(Kind: NormalAndEHCleanup, Addr: emission.Addr, Flags,
2155	/*LoadBlockVarAddr*/ false,
2156	CanThrow: cxxDestructorCanThrow(T: emission.Variable->getType()));
2157	}
2158	}
2159
2160	CodeGenFunction::Destroyer *
2161	CodeGenFunction::getDestroyer(QualType::DestructionKind kind) {
2162	switch (kind) {
2163	case QualType::DK_none: llvm_unreachable("no destroyer for trivial dtor");
2164	case QualType::DK_cxx_destructor:
2165	return destroyCXXObject;
2166	case QualType::DK_objc_strong_lifetime:
2167	return destroyARCStrongPrecise;
2168	case QualType::DK_objc_weak_lifetime:
2169	return destroyARCWeak;
2170	case QualType::DK_nontrivial_c_struct:
2171	return destroyNonTrivialCStruct;
2172	}
2173	llvm_unreachable("Unknown DestructionKind");
2174	}
2175
2176	/// pushEHDestroy - Push the standard destructor for the given type as
2177	/// an EH-only cleanup.
2178	void CodeGenFunction::pushEHDestroy(QualType::DestructionKind dtorKind,
2179	Address addr, QualType type) {
2180	assert(dtorKind && "cannot push destructor for trivial type");
2181	assert(needsEHCleanup(dtorKind));
2182
2183	pushDestroy(kind: EHCleanup, addr, type, destroyer: getDestroyer(kind: dtorKind), useEHCleanupForArray: true);
2184	}
2185
2186	/// pushDestroy - Push the standard destructor for the given type as
2187	/// at least a normal cleanup.
2188	void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
2189	Address addr, QualType type) {
2190	assert(dtorKind && "cannot push destructor for trivial type");
2191
2192	CleanupKind cleanupKind = getCleanupKind(kind: dtorKind);
2193	pushDestroy(kind: cleanupKind, addr, type, destroyer: getDestroyer(kind: dtorKind),
2194	useEHCleanupForArray: cleanupKind & EHCleanup);
2195	}
2196
2197	void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, Address addr,
2198	QualType type, Destroyer *destroyer,
2199	bool useEHCleanupForArray) {
2200	pushFullExprCleanup<DestroyObject>(kind: cleanupKind, A: addr, A: type,
2201	A: destroyer, A: useEHCleanupForArray);
2202	}
2203
2204	void CodeGenFunction::pushStackRestore(CleanupKind Kind, Address SPMem) {
2205	EHStack.pushCleanup<CallStackRestore>(Kind, A: SPMem);
2206	}
2207
2208	void CodeGenFunction::pushKmpcAllocFree(
2209	CleanupKind Kind, std::pair<llvm::Value *, llvm::Value *> AddrSizePair) {
2210	EHStack.pushCleanup<KmpcAllocFree>(Kind, A: AddrSizePair);
2211	}
2212
2213	void CodeGenFunction::pushLifetimeExtendedDestroy(CleanupKind cleanupKind,
2214	Address addr, QualType type,
2215	Destroyer *destroyer,
2216	bool useEHCleanupForArray) {
2217	// If we're not in a conditional branch, we don't need to bother generating a
2218	// conditional cleanup.
2219	if (!isInConditionalBranch()) {
2220	// Push an EH-only cleanup for the object now.
2221	// FIXME: When popping normal cleanups, we need to keep this EH cleanup
2222	// around in case a temporary's destructor throws an exception.
2223	if (cleanupKind & EHCleanup)
2224	EHStack.pushCleanup<DestroyObject>(
2225	Kind: static_cast<CleanupKind>(cleanupKind & ~NormalCleanup), A: addr, A: type,
2226	A: destroyer, A: useEHCleanupForArray);
2227
2228	return pushCleanupAfterFullExprWithActiveFlag<DestroyObject>(
2229	Kind: cleanupKind, ActiveFlag: Address::invalid(), A: addr, A: type, A: destroyer, A: useEHCleanupForArray);
2230	}
2231
2232	// Otherwise, we should only destroy the object if it's been initialized.
2233	// Re-use the active flag and saved address across both the EH and end of
2234	// scope cleanups.
2235
2236	using SavedType = typename DominatingValue<Address>::saved_type;
2237	using ConditionalCleanupType =
2238	EHScopeStack::ConditionalCleanup<DestroyObject, Address, QualType,
2239	Destroyer *, bool>;
2240
2241	Address ActiveFlag = createCleanupActiveFlag();
2242	SavedType SavedAddr = saveValueInCond(value: addr);
2243
2244	if (cleanupKind & EHCleanup) {
2245	EHStack.pushCleanup<ConditionalCleanupType>(
2246	Kind: static_cast<CleanupKind>(cleanupKind & ~NormalCleanup), A: SavedAddr, A: type,
2247	A: destroyer, A: useEHCleanupForArray);
2248	initFullExprCleanupWithFlag(ActiveFlag);
2249	}
2250
2251	pushCleanupAfterFullExprWithActiveFlag<ConditionalCleanupType>(
2252	Kind: cleanupKind, ActiveFlag, A: SavedAddr, A: type, A: destroyer,
2253	A: useEHCleanupForArray);
2254	}
2255
2256	/// emitDestroy - Immediately perform the destruction of the given
2257	/// object.
2258	///
2259	/// \param addr - the address of the object; a type*
2260	/// \param type - the type of the object; if an array type, all
2261	/// objects are destroyed in reverse order
2262	/// \param destroyer - the function to call to destroy individual
2263	/// elements
2264	/// \param useEHCleanupForArray - whether an EH cleanup should be
2265	/// used when destroying array elements, in case one of the
2266	/// destructions throws an exception
2267	void CodeGenFunction::emitDestroy(Address addr, QualType type,
2268	Destroyer *destroyer,
2269	bool useEHCleanupForArray) {
2270	const ArrayType *arrayType = getContext().getAsArrayType(T: type);
2271	if (!arrayType)
2272	return destroyer(*this, addr, type);
2273
2274	llvm::Value *length = emitArrayLength(arrayType, baseType&: type, addr);
2275
2276	CharUnits elementAlign =
2277	addr.getAlignment()
2278	.alignmentOfArrayElement(elementSize: getContext().getTypeSizeInChars(T: type));
2279
2280	// Normally we have to check whether the array is zero-length.
2281	bool checkZeroLength = true;
2282
2283	// But if the array length is constant, we can suppress that.
2284	if (llvm::ConstantInt *constLength = dyn_cast<llvm::ConstantInt>(Val: length)) {
2285	// ...and if it's constant zero, we can just skip the entire thing.
2286	if (constLength->isZero()) return;
2287	checkZeroLength = false;
2288	}
2289
2290	llvm::Value *begin = addr.emitRawPointer(CGF&: *this);
2291	llvm::Value *end =
2292	Builder.CreateInBoundsGEP(Ty: addr.getElementType(), Ptr: begin, IdxList: length);
2293	emitArrayDestroy(begin, end, elementType: type, elementAlign, destroyer,
2294	checkZeroLength, useEHCleanup: useEHCleanupForArray);
2295	}
2296
2297	/// emitArrayDestroy - Destroys all the elements of the given array,
2298	/// beginning from last to first. The array cannot be zero-length.
2299	///
2300	/// \param begin - a type* denoting the first element of the array
2301	/// \param end - a type* denoting one past the end of the array
2302	/// \param elementType - the element type of the array
2303	/// \param destroyer - the function to call to destroy elements
2304	/// \param useEHCleanup - whether to push an EH cleanup to destroy
2305	/// the remaining elements in case the destruction of a single
2306	/// element throws
2307	void CodeGenFunction::emitArrayDestroy(llvm::Value *begin,
2308	llvm::Value *end,
2309	QualType elementType,
2310	CharUnits elementAlign,
2311	Destroyer *destroyer,
2312	bool checkZeroLength,
2313	bool useEHCleanup) {
2314	assert(!elementType->isArrayType());
2315
2316	// The basic structure here is a do-while loop, because we don't
2317	// need to check for the zero-element case.
2318	llvm::BasicBlock *bodyBB = createBasicBlock(name: "arraydestroy.body");
2319	llvm::BasicBlock *doneBB = createBasicBlock(name: "arraydestroy.done");
2320
2321	if (checkZeroLength) {
2322	llvm::Value *isEmpty = Builder.CreateICmpEQ(LHS: begin, RHS: end,
2323	Name: "arraydestroy.isempty");
2324	Builder.CreateCondBr(Cond: isEmpty, True: doneBB, False: bodyBB);
2325	}
2326
2327	// Enter the loop body, making that address the current address.
2328	llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
2329	EmitBlock(BB: bodyBB);
2330	llvm::PHINode *elementPast =
2331	Builder.CreatePHI(Ty: begin->getType(), NumReservedValues: 2, Name: "arraydestroy.elementPast");
2332	elementPast->addIncoming(V: end, BB: entryBB);
2333
2334	// Shift the address back by one element.
2335	llvm::Value *negativeOne = llvm::ConstantInt::get(Ty: SizeTy, V: -1, IsSigned: true);
2336	llvm::Type *llvmElementType = ConvertTypeForMem(T: elementType);
2337	llvm::Value *element = Builder.CreateInBoundsGEP(
2338	Ty: llvmElementType, Ptr: elementPast, IdxList: negativeOne, Name: "arraydestroy.element");
2339
2340	if (useEHCleanup)
2341	pushRegularPartialArrayCleanup(arrayBegin: begin, arrayEnd: element, elementType, elementAlignment: elementAlign,
2342	destroyer);
2343
2344	// Perform the actual destruction there.
2345	destroyer(*this, Address(element, llvmElementType, elementAlign),
2346	elementType);
2347
2348	if (useEHCleanup)
2349	PopCleanupBlock();
2350
2351	// Check whether we've reached the end.
2352	llvm::Value *done = Builder.CreateICmpEQ(LHS: element, RHS: begin, Name: "arraydestroy.done");
2353	Builder.CreateCondBr(Cond: done, True: doneBB, False: bodyBB);
2354	elementPast->addIncoming(V: element, BB: Builder.GetInsertBlock());
2355
2356	// Done.
2357	EmitBlock(BB: doneBB);
2358	}
2359
2360	/// Perform partial array destruction as if in an EH cleanup. Unlike
2361	/// emitArrayDestroy, the element type here may still be an array type.
2362	static void emitPartialArrayDestroy(CodeGenFunction &CGF,
2363	llvm::Value *begin, llvm::Value *end,
2364	QualType type, CharUnits elementAlign,
2365	CodeGenFunction::Destroyer *destroyer) {
2366	llvm::Type *elemTy = CGF.ConvertTypeForMem(T: type);
2367
2368	// If the element type is itself an array, drill down.
2369	unsigned arrayDepth = 0;
2370	while (const ArrayType *arrayType = CGF.getContext().getAsArrayType(T: type)) {
2371	// VLAs don't require a GEP index to walk into.
2372	if (!isa<VariableArrayType>(Val: arrayType))
2373	arrayDepth++;
2374	type = arrayType->getElementType();
2375	}
2376
2377	if (arrayDepth) {
2378	llvm::Value *zero = llvm::ConstantInt::get(Ty: CGF.SizeTy, V: 0);
2379
2380	SmallVector<llvm::Value*,4> gepIndices(arrayDepth+1, zero);
2381	begin = CGF.Builder.CreateInBoundsGEP(
2382	Ty: elemTy, Ptr: begin, IdxList: gepIndices, Name: "pad.arraybegin");
2383	end = CGF.Builder.CreateInBoundsGEP(
2384	Ty: elemTy, Ptr: end, IdxList: gepIndices, Name: "pad.arrayend");
2385	}
2386
2387	// Destroy the array. We don't ever need an EH cleanup because we
2388	// assume that we're in an EH cleanup ourselves, so a throwing
2389	// destructor causes an immediate terminate.
2390	CGF.emitArrayDestroy(begin, end, elementType: type, elementAlign, destroyer,
2391	/*checkZeroLength*/ true, /*useEHCleanup*/ false);
2392	}
2393
2394	namespace {
2395	/// RegularPartialArrayDestroy - a cleanup which performs a partial
2396	/// array destroy where the end pointer is regularly determined and
2397	/// does not need to be loaded from a local.
2398	class RegularPartialArrayDestroy final : public EHScopeStack::Cleanup {
2399	llvm::Value *ArrayBegin;
2400	llvm::Value *ArrayEnd;
2401	QualType ElementType;
2402	CodeGenFunction::Destroyer *Destroyer;
2403	CharUnits ElementAlign;
2404	public:
2405	RegularPartialArrayDestroy(llvm::Value *arrayBegin, llvm::Value *arrayEnd,
2406	QualType elementType, CharUnits elementAlign,
2407	CodeGenFunction::Destroyer *destroyer)
2408	: ArrayBegin(arrayBegin), ArrayEnd(arrayEnd),
2409	ElementType(elementType), Destroyer(destroyer),
2410	ElementAlign(elementAlign) {}
2411
2412	void Emit(CodeGenFunction &CGF, Flags flags) override {
2413	emitPartialArrayDestroy(CGF, ArrayBegin, ArrayEnd,
2414	ElementType, ElementAlign, Destroyer);
2415	}
2416	};
2417
2418	/// IrregularPartialArrayDestroy - a cleanup which performs a
2419	/// partial array destroy where the end pointer is irregularly
2420	/// determined and must be loaded from a local.
2421	class IrregularPartialArrayDestroy final : public EHScopeStack::Cleanup {
2422	llvm::Value *ArrayBegin;
2423	Address ArrayEndPointer;
2424	QualType ElementType;
2425	CodeGenFunction::Destroyer *Destroyer;
2426	CharUnits ElementAlign;
2427	public:
2428	IrregularPartialArrayDestroy(llvm::Value *arrayBegin,
2429	Address arrayEndPointer,
2430	QualType elementType,
2431	CharUnits elementAlign,
2432	CodeGenFunction::Destroyer *destroyer)
2433	: ArrayBegin(arrayBegin), ArrayEndPointer(arrayEndPointer),
2434	ElementType(elementType), Destroyer(destroyer),
2435	ElementAlign(elementAlign) {}
2436
2437	void Emit(CodeGenFunction &CGF, Flags flags) override {
2438	llvm::Value *arrayEnd = CGF.Builder.CreateLoad(Addr: ArrayEndPointer);
2439	emitPartialArrayDestroy(CGF, ArrayBegin, arrayEnd,
2440	ElementType, ElementAlign, Destroyer);
2441	}
2442	};
2443	} // end anonymous namespace
2444
2445	/// pushIrregularPartialArrayCleanup - Push an EH cleanup to destroy
2446	/// already-constructed elements of the given array. The cleanup
2447	/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
2448	///
2449	/// \param elementType - the immediate element type of the array;
2450	/// possibly still an array type
2451	void CodeGenFunction::pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
2452	Address arrayEndPointer,
2453	QualType elementType,
2454	CharUnits elementAlign,
2455	Destroyer *destroyer) {
2456	pushFullExprCleanup<IrregularPartialArrayDestroy>(kind: EHCleanup,
2457	A: arrayBegin, A: arrayEndPointer,
2458	A: elementType, A: elementAlign,
2459	A: destroyer);
2460	}
2461
2462	/// pushRegularPartialArrayCleanup - Push an EH cleanup to destroy
2463	/// already-constructed elements of the given array. The cleanup
2464	/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
2465	///
2466	/// \param elementType - the immediate element type of the array;
2467	/// possibly still an array type
2468	void CodeGenFunction::pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
2469	llvm::Value *arrayEnd,
2470	QualType elementType,
2471	CharUnits elementAlign,
2472	Destroyer *destroyer) {
2473	pushFullExprCleanup<RegularPartialArrayDestroy>(kind: EHCleanup,
2474	A: arrayBegin, A: arrayEnd,
2475	A: elementType, A: elementAlign,
2476	A: destroyer);
2477	}
2478
2479	/// Lazily declare the @llvm.lifetime.start intrinsic.
2480	llvm::Function *CodeGenModule::getLLVMLifetimeStartFn() {
2481	if (LifetimeStartFn)
2482	return LifetimeStartFn;
2483	LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
2484	llvm::Intrinsic::lifetime_start, AllocaInt8PtrTy);
2485	return LifetimeStartFn;
2486	}
2487
2488	/// Lazily declare the @llvm.lifetime.end intrinsic.
2489	llvm::Function *CodeGenModule::getLLVMLifetimeEndFn() {
2490	if (LifetimeEndFn)
2491	return LifetimeEndFn;
2492	LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
2493	llvm::Intrinsic::lifetime_end, AllocaInt8PtrTy);
2494	return LifetimeEndFn;
2495	}
2496
2497	namespace {
2498	/// A cleanup to perform a release of an object at the end of a
2499	/// function. This is used to balance out the incoming +1 of a
2500	/// ns_consumed argument when we can't reasonably do that just by
2501	/// not doing the initial retain for a __block argument.
2502	struct ConsumeARCParameter final : EHScopeStack::Cleanup {
2503	ConsumeARCParameter(llvm::Value *param,
2504	ARCPreciseLifetime_t precise)
2505	: Param(param), Precise(precise) {}
2506
2507	llvm::Value *Param;
2508	ARCPreciseLifetime_t Precise;
2509
2510	void Emit(CodeGenFunction &CGF, Flags flags) override {
2511	CGF.EmitARCRelease(value: Param, precise: Precise);
2512	}
2513	};
2514	} // end anonymous namespace
2515
2516	/// Emit an alloca (or GlobalValue depending on target)
2517	/// for the specified parameter and set up LocalDeclMap.
2518	void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
2519	unsigned ArgNo) {
2520	bool NoDebugInfo = false;
2521	// FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
2522	assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
2523	"Invalid argument to EmitParmDecl");
2524
2525	// Set the name of the parameter's initial value to make IR easier to
2526	// read. Don't modify the names of globals.
2527	if (!isa<llvm::GlobalValue>(Val: Arg.getAnyValue()))
2528	Arg.getAnyValue()->setName(D.getName());
2529
2530	QualType Ty = D.getType();
2531
2532	// Use better IR generation for certain implicit parameters.
2533	if (auto IPD = dyn_cast<ImplicitParamDecl>(Val: &D)) {
2534	// The only implicit argument a block has is its literal.
2535	// This may be passed as an inalloca'ed value on Windows x86.
2536	if (BlockInfo) {
2537	llvm::Value *V = Arg.isIndirect()
2538	? Builder.CreateLoad(Addr: Arg.getIndirectAddress())
2539	: Arg.getDirectValue();
2540	setBlockContextParameter(D: IPD, argNum: ArgNo, ptr: V);
2541	return;
2542	}
2543	// Suppressing debug info for ThreadPrivateVar parameters, else it hides
2544	// debug info of TLS variables.
2545	NoDebugInfo =
2546	(IPD->getParameterKind() == ImplicitParamKind::ThreadPrivateVar);
2547	}
2548
2549	Address DeclPtr = Address::invalid();
2550	RawAddress AllocaPtr = Address::invalid();
2551	bool DoStore = false;
2552	bool IsScalar = hasScalarEvaluationKind(T: Ty);
2553	bool UseIndirectDebugAddress = false;
2554
2555	// If we already have a pointer to the argument, reuse the input pointer.
2556	if (Arg.isIndirect()) {
2557	DeclPtr = Arg.getIndirectAddress();
2558	DeclPtr = DeclPtr.withElementType(ElemTy: ConvertTypeForMem(T: Ty));
2559	// Indirect argument is in alloca address space, which may be different
2560	// from the default address space.
2561	auto AllocaAS = CGM.getASTAllocaAddressSpace();
2562	auto *V = DeclPtr.emitRawPointer(CGF&: *this);
2563	AllocaPtr = RawAddress(V, DeclPtr.getElementType(), DeclPtr.getAlignment());
2564
2565	// For truly ABI indirect arguments -- those that are not `byval` -- store
2566	// the address of the argument on the stack to preserve debug information.
2567	ABIArgInfo ArgInfo = CurFnInfo->arguments()[ArgNo - 1].info;
2568	if (ArgInfo.isIndirect())
2569	UseIndirectDebugAddress = !ArgInfo.getIndirectByVal();
2570	if (UseIndirectDebugAddress) {
2571	auto PtrTy = getContext().getPointerType(T: Ty);
2572	AllocaPtr = CreateMemTemp(PtrTy, getContext().getTypeAlignInChars(PtrTy),
2573	D.getName() + ".indirect_addr");
2574	EmitStoreOfScalar(V, AllocaPtr, /* Volatile */ false, PtrTy);
2575	}
2576
2577	auto SrcLangAS = getLangOpts().OpenCL ? LangAS::opencl_private : AllocaAS;
2578	auto DestLangAS =
2579	getLangOpts().OpenCL ? LangAS::opencl_private : LangAS::Default;
2580	if (SrcLangAS != DestLangAS) {
2581	assert(getContext().getTargetAddressSpace(SrcLangAS) ==
2582	CGM.getDataLayout().getAllocaAddrSpace());
2583	auto DestAS = getContext().getTargetAddressSpace(AS: DestLangAS);
2584	auto *T = llvm::PointerType::get(C&: getLLVMContext(), AddressSpace: DestAS);
2585	DeclPtr =
2586	DeclPtr.withPointer(NewPointer: getTargetHooks().performAddrSpaceCast(
2587	*this, V, SrcLangAS, DestLangAS, T, true),
2588	IsKnownNonNull: DeclPtr.isKnownNonNull());
2589	}
2590
2591	// Push a destructor cleanup for this parameter if the ABI requires it.
2592	// Don't push a cleanup in a thunk for a method that will also emit a
2593	// cleanup.
2594	if (Ty->isRecordType() && !CurFuncIsThunk &&
2595	Ty->castAs<RecordType>()->getDecl()->isParamDestroyedInCallee()) {
2596	if (QualType::DestructionKind DtorKind =
2597	D.needsDestruction(Ctx: getContext())) {
2598	assert((DtorKind == QualType::DK_cxx_destructor ||
2599	DtorKind == QualType::DK_nontrivial_c_struct) &&
2600	"unexpected destructor type");
2601	pushDestroy(dtorKind: DtorKind, addr: DeclPtr, type: Ty);
2602	CalleeDestructedParamCleanups[cast<ParmVarDecl>(Val: &D)] =
2603	EHStack.stable_begin();
2604	}
2605	}
2606	} else {
2607	// Check if the parameter address is controlled by OpenMP runtime.
2608	Address OpenMPLocalAddr =
2609	getLangOpts().OpenMP
2610	? CGM.getOpenMPRuntime().getAddressOfLocalVariable(CGF&: *this, VD: &D)
2611	: Address::invalid();
2612	if (getLangOpts().OpenMP && OpenMPLocalAddr.isValid()) {
2613	DeclPtr = OpenMPLocalAddr;
2614	AllocaPtr = DeclPtr;
2615	} else {
2616	// Otherwise, create a temporary to hold the value.
2617	DeclPtr = CreateMemTemp(Ty, getContext().getDeclAlign(&D),
2618	D.getName() + ".addr", &AllocaPtr);
2619	}
2620	DoStore = true;
2621	}
2622
2623	llvm::Value *ArgVal = (DoStore ? Arg.getDirectValue() : nullptr);
2624
2625	LValue lv = MakeAddrLValue(Addr: DeclPtr, T: Ty);
2626	if (IsScalar) {
2627	Qualifiers qs = Ty.getQualifiers();
2628	if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
2629	// We honor __attribute__((ns_consumed)) for types with lifetime.
2630	// For __strong, it's handled by just skipping the initial retain;
2631	// otherwise we have to balance out the initial +1 with an extra
2632	// cleanup to do the release at the end of the function.
2633	bool isConsumed = D.hasAttr<NSConsumedAttr>();
2634
2635	// If a parameter is pseudo-strong then we can omit the implicit retain.
2636	if (D.isARCPseudoStrong()) {
2637	assert(lt == Qualifiers::OCL_Strong &&
2638	"pseudo-strong variable isn't strong?");
2639	assert(qs.hasConst() && "pseudo-strong variable should be const!");
2640	lt = Qualifiers::OCL_ExplicitNone;
2641	}
2642
2643	// Load objects passed indirectly.
2644	if (Arg.isIndirect() && !ArgVal)
2645	ArgVal = Builder.CreateLoad(Addr: DeclPtr);
2646
2647	if (lt == Qualifiers::OCL_Strong) {
2648	if (!isConsumed) {
2649	if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
2650	// use objc_storeStrong(&dest, value) for retaining the
2651	// object. But first, store a null into 'dest' because
2652	// objc_storeStrong attempts to release its old value.
2653	llvm::Value *Null = CGM.EmitNullConstant(T: D.getType());
2654	EmitStoreOfScalar(value: Null, lvalue: lv, /* isInitialization */ isInit: true);
2655	EmitARCStoreStrongCall(addr: lv.getAddress(CGF&: *this), value: ArgVal, resultIgnored: true);
2656	DoStore = false;
2657	}
2658	else
2659	// Don't use objc_retainBlock for block pointers, because we
2660	// don't want to Block_copy something just because we got it
2661	// as a parameter.
2662	ArgVal = EmitARCRetainNonBlock(value: ArgVal);
2663	}
2664	} else {
2665	// Push the cleanup for a consumed parameter.
2666	if (isConsumed) {
2667	ARCPreciseLifetime_t precise = (D.hasAttr<ObjCPreciseLifetimeAttr>()
2668	? ARCPreciseLifetime : ARCImpreciseLifetime);
2669	EHStack.pushCleanup<ConsumeARCParameter>(Kind: getARCCleanupKind(), A: ArgVal,
2670	A: precise);
2671	}
2672
2673	if (lt == Qualifiers::OCL_Weak) {
2674	EmitARCInitWeak(addr: DeclPtr, value: ArgVal);
2675	DoStore = false; // The weak init is a store, no need to do two.
2676	}
2677	}
2678
2679	// Enter the cleanup scope.
2680	EmitAutoVarWithLifetime(CGF&: *this, var: D, addr: DeclPtr, lifetime: lt);
2681	}
2682	}
2683
2684	// Store the initial value into the alloca.
2685	if (DoStore)
2686	EmitStoreOfScalar(value: ArgVal, lvalue: lv, /* isInitialization */ isInit: true);
2687
2688	setAddrOfLocalVar(VD: &D, Addr: DeclPtr);
2689
2690	// Emit debug info for param declarations in non-thunk functions.
2691	if (CGDebugInfo *DI = getDebugInfo()) {
2692	if (CGM.getCodeGenOpts().hasReducedDebugInfo() && !CurFuncIsThunk &&
2693	!NoDebugInfo) {
2694	llvm::DILocalVariable *DILocalVar = DI->EmitDeclareOfArgVariable(
2695	Decl: &D, AI: AllocaPtr.getPointer(), ArgNo, Builder, UsePointerValue: UseIndirectDebugAddress);
2696	if (const auto *Var = dyn_cast_or_null<ParmVarDecl>(Val: &D))
2697	DI->getParamDbgMappings().insert(KV: {Var, DILocalVar});
2698	}
2699	}
2700
2701	if (D.hasAttr<AnnotateAttr>())
2702	EmitVarAnnotations(D: &D, V: DeclPtr.emitRawPointer(CGF&: *this));
2703
2704	// We can only check return value nullability if all arguments to the
2705	// function satisfy their nullability preconditions. This makes it necessary
2706	// to emit null checks for args in the function body itself.
2707	if (requiresReturnValueNullabilityCheck()) {
2708	auto Nullability = Ty->getNullability();
2709	if (Nullability && *Nullability == NullabilityKind::NonNull) {
2710	SanitizerScope SanScope(this);
2711	RetValNullabilityPrecondition =
2712	Builder.CreateAnd(LHS: RetValNullabilityPrecondition,
2713	RHS: Builder.CreateIsNotNull(Arg: Arg.getAnyValue()));
2714	}
2715	}
2716	}
2717
2718	void CodeGenModule::EmitOMPDeclareReduction(const OMPDeclareReductionDecl *D,
2719	CodeGenFunction *CGF) {
2720	if (!LangOpts.OpenMP || (!LangOpts.EmitAllDecls && !D->isUsed()))
2721	return;
2722	getOpenMPRuntime().emitUserDefinedReduction(CGF, D);
2723	}
2724
2725	void CodeGenModule::EmitOMPDeclareMapper(const OMPDeclareMapperDecl *D,
2726	CodeGenFunction *CGF) {
2727	if (!LangOpts.OpenMP || LangOpts.OpenMPSimd ||
2728	(!LangOpts.EmitAllDecls && !D->isUsed()))
2729	return;
2730	getOpenMPRuntime().emitUserDefinedMapper(D, CGF);
2731	}
2732
2733	void CodeGenModule::EmitOMPRequiresDecl(const OMPRequiresDecl *D) {
2734	getOpenMPRuntime().processRequiresDirective(D);
2735	}
2736
2737	void CodeGenModule::EmitOMPAllocateDecl(const OMPAllocateDecl *D) {
2738	for (const Expr *E : D->varlists()) {
2739	const auto *DE = cast<DeclRefExpr>(Val: E);
2740	const auto *VD = cast<VarDecl>(Val: DE->getDecl());
2741
2742	// Skip all but globals.
2743	if (!VD->hasGlobalStorage())
2744	continue;
2745
2746	// Check if the global has been materialized yet or not. If not, we are done
2747	// as any later generation will utilize the OMPAllocateDeclAttr. However, if
2748	// we already emitted the global we might have done so before the
2749	// OMPAllocateDeclAttr was attached, leading to the wrong address space
2750	// (potentially). While not pretty, common practise is to remove the old IR
2751	// global and generate a new one, so we do that here too. Uses are replaced
2752	// properly.
2753	StringRef MangledName = getMangledName(GD: VD);
2754	llvm::GlobalValue *Entry = GetGlobalValue(Ref: MangledName);
2755	if (!Entry)
2756	continue;
2757
2758	// We can also keep the existing global if the address space is what we
2759	// expect it to be, if not, it is replaced.
2760	QualType ASTTy = VD->getType();
2761	clang::LangAS GVAS = GetGlobalVarAddressSpace(D: VD);
2762	auto TargetAS = getContext().getTargetAddressSpace(AS: GVAS);
2763	if (Entry->getType()->getAddressSpace() == TargetAS)
2764	continue;
2765
2766	// Make a new global with the correct type / address space.
2767	llvm::Type *Ty = getTypes().ConvertTypeForMem(T: ASTTy);
2768	llvm::PointerType *PTy = llvm::PointerType::get(ElementType: Ty, AddressSpace: TargetAS);
2769
2770	// Replace all uses of the old global with a cast. Since we mutate the type
2771	// in place we neeed an intermediate that takes the spot of the old entry
2772	// until we can create the cast.
2773	llvm::GlobalVariable *DummyGV = new llvm::GlobalVariable(
2774	getModule(), Entry->getValueType(), false,
2775	llvm::GlobalValue::CommonLinkage, nullptr, "dummy", nullptr,
2776	llvm::GlobalVariable::NotThreadLocal, Entry->getAddressSpace());
2777	Entry->replaceAllUsesWith(V: DummyGV);
2778
2779	Entry->mutateType(Ty: PTy);
2780	llvm::Constant *NewPtrForOldDecl =
2781	llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
2782	C: Entry, Ty: DummyGV->getType());
2783
2784	// Now we have a casted version of the changed global, the dummy can be
2785	// replaced and deleted.
2786	DummyGV->replaceAllUsesWith(V: NewPtrForOldDecl);
2787	DummyGV->eraseFromParent();
2788	}
2789	}
2790
2791	std::optional<CharUnits>
2792	CodeGenModule::getOMPAllocateAlignment(const VarDecl *VD) {
2793	if (const auto *AA = VD->getAttr<OMPAllocateDeclAttr>()) {
2794	if (Expr *Alignment = AA->getAlignment()) {
2795	unsigned UserAlign =
2796	Alignment->EvaluateKnownConstInt(Ctx: getContext()).getExtValue();
2797	CharUnits NaturalAlign =
2798	getNaturalTypeAlignment(T: VD->getType().getNonReferenceType());
2799
2800	// OpenMP5.1 pg 185 lines 7-10
2801	// Each item in the align modifier list must be aligned to the maximum
2802	// of the specified alignment and the type's natural alignment.
2803	return CharUnits::fromQuantity(
2804	Quantity: std::max<unsigned>(a: UserAlign, b: NaturalAlign.getQuantity()));
2805	}
2806	}
2807	return std::nullopt;
2808	}
2809