clang 10.0.0git

CGVTables.cpp
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1 //===--- CGVTables.cpp - Emit LLVM Code for C++ vtables -------------------===//
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 dealing with C++ code generation of virtual tables.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "CGCXXABI.h"
14 #include "CodeGenFunction.h"
15 #include "CodeGenModule.h"
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/CXXInheritance.h"
18 #include "clang/AST/RecordLayout.h"
19 #include "clang/Basic/CodeGenOptions.h"
20 #include "clang/CodeGen/CGFunctionInfo.h"
21 #include "clang/CodeGen/ConstantInitBuilder.h"
22 #include "llvm/IR/IntrinsicInst.h"
23 #include "llvm/Support/Format.h"
24 #include "llvm/Transforms/Utils/Cloning.h"
25 #include <algorithm>
26 #include <cstdio>
27
28 using namespace clang;
29 using namespace CodeGen;
30
31 CodeGenVTables::CodeGenVTables(CodeGenModule &CGM)
32 : CGM(CGM), VTContext(CGM.getContext().getVTableContext()) {}
33
34 llvm::Constant *CodeGenModule::GetAddrOfThunk(StringRef Name, llvm::Type *FnTy,
35 GlobalDecl GD) {
36 return GetOrCreateLLVMFunction(Name, FnTy, GD, /*ForVTable=*/true,
37 /*DontDefer=*/true, /*IsThunk=*/true);
38 }
39
40 static void setThunkProperties(CodeGenModule &CGM, const ThunkInfo &Thunk,
41 llvm::Function *ThunkFn, bool ForVTable,
42 GlobalDecl GD) {
43 CGM.setFunctionLinkage(GD, ThunkFn);
44 CGM.getCXXABI().setThunkLinkage(ThunkFn, ForVTable, GD,
45 !Thunk.Return.isEmpty());
46
47 // Set the right visibility.
48 CGM.setGVProperties(ThunkFn, GD);
49
50 if (!CGM.getCXXABI().exportThunk()) {
51 ThunkFn->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
52 ThunkFn->setDSOLocal(true);
53 }
54
55 if (CGM.supportsCOMDAT() && ThunkFn->isWeakForLinker())
56 ThunkFn->setComdat(CGM.getModule().getOrInsertComdat(ThunkFn->getName()));
57 }
58
59 #ifndef NDEBUG
60 static bool similar(const ABIArgInfo &infoL, CanQualType typeL,
61 const ABIArgInfo &infoR, CanQualType typeR) {
62 return (infoL.getKind() == infoR.getKind() &&
63 (typeL == typeR ||
64 (isa<PointerType>(typeL) && isa<PointerType>(typeR)) ||
65 (isa<ReferenceType>(typeL) && isa<ReferenceType>(typeR))));
66 }
67 #endif
68
69 static RValue PerformReturnAdjustment(CodeGenFunction &CGF,
70 QualType ResultType, RValue RV,
71 const ThunkInfo &Thunk) {
72 // Emit the return adjustment.
73 bool NullCheckValue = !ResultType->isReferenceType();
74
75 llvm::BasicBlock *AdjustNull = nullptr;
76 llvm::BasicBlock *AdjustNotNull = nullptr;
77 llvm::BasicBlock *AdjustEnd = nullptr;
78
79 llvm::Value *ReturnValue = RV.getScalarVal();
80
81 if (NullCheckValue) {
82 AdjustNull = CGF.createBasicBlock("adjust.null");
83 AdjustNotNull = CGF.createBasicBlock("adjust.notnull");
84 AdjustEnd = CGF.createBasicBlock("adjust.end");
85
86 llvm::Value *IsNull = CGF.Builder.CreateIsNull(ReturnValue);
87 CGF.Builder.CreateCondBr(IsNull, AdjustNull, AdjustNotNull);
88 CGF.EmitBlock(AdjustNotNull);
89 }
90
91 auto ClassDecl = ResultType->getPointeeType()->getAsCXXRecordDecl();
92 auto ClassAlign = CGF.CGM.getClassPointerAlignment(ClassDecl);
93 ReturnValue = CGF.CGM.getCXXABI().performReturnAdjustment(CGF,
94 Address(ReturnValue, ClassAlign),
95 Thunk.Return);
96
97 if (NullCheckValue) {
98 CGF.Builder.CreateBr(AdjustEnd);
99 CGF.EmitBlock(AdjustNull);
100 CGF.Builder.CreateBr(AdjustEnd);
101 CGF.EmitBlock(AdjustEnd);
102
103 llvm::PHINode *PHI = CGF.Builder.CreatePHI(ReturnValue->getType(), 2);
104 PHI->addIncoming(ReturnValue, AdjustNotNull);
105 PHI->addIncoming(llvm::Constant::getNullValue(ReturnValue->getType()),
106 AdjustNull);
107 ReturnValue = PHI;
108 }
109
110 return RValue::get(ReturnValue);
111 }
112
113 /// This function clones a function's DISubprogram node and enters it into
114 /// a value map with the intent that the map can be utilized by the cloner
115 /// to short-circuit Metadata node mapping.
116 /// Furthermore, the function resolves any DILocalVariable nodes referenced
117 /// by dbg.value intrinsics so they can be properly mapped during cloning.
118 static void resolveTopLevelMetadata(llvm::Function *Fn,
119 llvm::ValueToValueMapTy &VMap) {
120 // Clone the DISubprogram node and put it into the Value map.
121 auto *DIS = Fn->getSubprogram();
122 if (!DIS)
123 return;
124 auto *NewDIS = DIS->replaceWithDistinct(DIS->clone());
125 VMap.MD()[DIS].reset(NewDIS);
126
127 // Find all llvm.dbg.declare intrinsics and resolve the DILocalVariable nodes
128 // they are referencing.
129 for (auto &BB : Fn->getBasicBlockList()) {
130 for (auto &I : BB) {
131 if (auto *DII = dyn_cast<llvm::DbgVariableIntrinsic>(&I)) {
132 auto *DILocal = DII->getVariable();
133 if (!DILocal->isResolved())
134 DILocal->resolve();
135 }
136 }
137 }
138 }
139
140 // This function does roughly the same thing as GenerateThunk, but in a
141 // very different way, so that va_start and va_end work correctly.
142 // FIXME: This function assumes "this" is the first non-sret LLVM argument of
143 // a function, and that there is an alloca built in the entry block
144 // for all accesses to "this".
145 // FIXME: This function assumes there is only one "ret" statement per function.
146 // FIXME: Cloning isn't correct in the presence of indirect goto!
147 // FIXME: This implementation of thunks bloats codesize by duplicating the
148 // function definition. There are alternatives:
149 // 1. Add some sort of stub support to LLVM for cases where we can
150 // do a this adjustment, then a sibcall.
151 // 2. We could transform the definition to take a va_list instead of an
152 // actual variable argument list, then have the thunks (including a
153 // no-op thunk for the regular definition) call va_start/va_end.
154 // There's a bit of per-call overhead for this solution, but it's
155 // better for codesize if the definition is long.
156 llvm::Function *
157 CodeGenFunction::GenerateVarArgsThunk(llvm::Function *Fn,
158 const CGFunctionInfo &FnInfo,
159 GlobalDecl GD, const ThunkInfo &Thunk) {
160 const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
161 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
162 QualType ResultType = FPT->getReturnType();
163
164 // Get the original function
165 assert(FnInfo.isVariadic());
166 llvm::Type *Ty = CGM.getTypes().GetFunctionType(FnInfo);
167 llvm::Value *Callee = CGM.GetAddrOfFunction(GD, Ty, /*ForVTable=*/true);
168 llvm::Function *BaseFn = cast<llvm::Function>(Callee);
169
170 // Cloning can't work if we don't have a definition. The Microsoft ABI may
171 // require thunks when a definition is not available. Emit an error in these
172 // cases.
173 if (!MD->isDefined()) {
174 CGM.ErrorUnsupported(MD, "return-adjusting thunk with variadic arguments");
175 return Fn;
176 }
177 assert(!BaseFn->isDeclaration() && "cannot clone undefined variadic method");
178
179 // Clone to thunk.
180 llvm::ValueToValueMapTy VMap;
181
182 // We are cloning a function while some Metadata nodes are still unresolved.
183 // Ensure that the value mapper does not encounter any of them.
184 resolveTopLevelMetadata(BaseFn, VMap);
185 llvm::Function *NewFn = llvm::CloneFunction(BaseFn, VMap);
186 Fn->replaceAllUsesWith(NewFn);
187 NewFn->takeName(Fn);
188 Fn->eraseFromParent();
189 Fn = NewFn;
190
191 // "Initialize" CGF (minimally).
192 CurFn = Fn;
193
194 // Get the "this" value
195 llvm::Function::arg_iterator AI = Fn->arg_begin();
196 if (CGM.ReturnTypeUsesSRet(FnInfo))
197 ++AI;
198
199 // Find the first store of "this", which will be to the alloca associated
200 // with "this".
201 Address ThisPtr(&*AI, CGM.getClassPointerAlignment(MD->getParent()));
202 llvm::BasicBlock *EntryBB = &Fn->front();
203 llvm::BasicBlock::iterator ThisStore =
204 std::find_if(EntryBB->begin(), EntryBB->end(), [&](llvm::Instruction &I) {
205 return isa<llvm::StoreInst>(I) &&
206 I.getOperand(0) == ThisPtr.getPointer();
207 });
208 assert(ThisStore != EntryBB->end() &&
209 "Store of this should be in entry block?");
210 // Adjust "this", if necessary.
211 Builder.SetInsertPoint(&*ThisStore);
212 llvm::Value *AdjustedThisPtr =
213 CGM.getCXXABI().performThisAdjustment(*this, ThisPtr, Thunk.This);
214 AdjustedThisPtr = Builder.CreateBitCast(AdjustedThisPtr,
215 ThisStore->getOperand(0)->getType());
216 ThisStore->setOperand(0, AdjustedThisPtr);
217
218 if (!Thunk.Return.isEmpty()) {
219 // Fix up the returned value, if necessary.
220 for (llvm::BasicBlock &BB : *Fn) {
221 llvm::Instruction *T = BB.getTerminator();
222 if (isa<llvm::ReturnInst>(T)) {
223 RValue RV = RValue::get(T->getOperand(0));
224 T->eraseFromParent();
225 Builder.SetInsertPoint(&BB);
226 RV = PerformReturnAdjustment(*this, ResultType, RV, Thunk);
227 Builder.CreateRet(RV.getScalarVal());
228 break;
229 }
230 }
231 }
232
233 return Fn;
234 }
235
236 void CodeGenFunction::StartThunk(llvm::Function *Fn, GlobalDecl GD,
237 const CGFunctionInfo &FnInfo,
238 bool IsUnprototyped) {
239 assert(!CurGD.getDecl() && "CurGD was already set!");
240 CurGD = GD;
241 CurFuncIsThunk = true;
242
243 // Build FunctionArgs.
244 const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
245 QualType ThisType = MD->getThisType();
246 QualType ResultType;
247 if (IsUnprototyped)
248 ResultType = CGM.getContext().VoidTy;
249 else if (CGM.getCXXABI().HasThisReturn(GD))
250 ResultType = ThisType;
251 else if (CGM.getCXXABI().hasMostDerivedReturn(GD))
252 ResultType = CGM.getContext().VoidPtrTy;
253 else
254 ResultType = MD->getType()->castAs<FunctionProtoType>()->getReturnType();
255 FunctionArgList FunctionArgs;
256
257 // Create the implicit 'this' parameter declaration.
258 CGM.getCXXABI().buildThisParam(*this, FunctionArgs);
259
260 // Add the rest of the parameters, if we have a prototype to work with.
261 if (!IsUnprototyped) {
262 FunctionArgs.append(MD->param_begin(), MD->param_end());
263
264 if (isa<CXXDestructorDecl>(MD))
265 CGM.getCXXABI().addImplicitStructorParams(*this, ResultType,
266 FunctionArgs);
267 }
268
269 // Start defining the function.
270 auto NL = ApplyDebugLocation::CreateEmpty(*this);
271 StartFunction(GlobalDecl(), ResultType, Fn, FnInfo, FunctionArgs,
272 MD->getLocation());
273 // Create a scope with an artificial location for the body of this function.
274 auto AL = ApplyDebugLocation::CreateArtificial(*this);
275
276 // Since we didn't pass a GlobalDecl to StartFunction, do this ourselves.
277 CGM.getCXXABI().EmitInstanceFunctionProlog(*this);
278 CXXThisValue = CXXABIThisValue;
279 CurCodeDecl = MD;
280 CurFuncDecl = MD;
281 }
282
283 void CodeGenFunction::FinishThunk() {
284 // Clear these to restore the invariants expected by
285 // StartFunction/FinishFunction.
286 CurCodeDecl = nullptr;
287 CurFuncDecl = nullptr;
288
289 FinishFunction();
290 }
291
292 void CodeGenFunction::EmitCallAndReturnForThunk(llvm::FunctionCallee Callee,
293 const ThunkInfo *Thunk,
294 bool IsUnprototyped) {
295 assert(isa<CXXMethodDecl>(CurGD.getDecl()) &&
296 "Please use a new CGF for this thunk");
297 const CXXMethodDecl *MD = cast<CXXMethodDecl>(CurGD.getDecl());
298
299 // Adjust the 'this' pointer if necessary
300 llvm::Value *AdjustedThisPtr =
301 Thunk ? CGM.getCXXABI().performThisAdjustment(
302 *this, LoadCXXThisAddress(), Thunk->This)
303 : LoadCXXThis();
304
305 // If perfect forwarding is required a variadic method, a method using
306 // inalloca, or an unprototyped thunk, use musttail. Emit an error if this
307 // thunk requires a return adjustment, since that is impossible with musttail.
308 if (CurFnInfo->usesInAlloca() || CurFnInfo->isVariadic() || IsUnprototyped) {
309 if (Thunk && !Thunk->Return.isEmpty()) {
310 if (IsUnprototyped)
311 CGM.ErrorUnsupported(
312 MD, "return-adjusting thunk with incomplete parameter type");
313 else if (CurFnInfo->isVariadic())
314 llvm_unreachable("shouldn't try to emit musttail return-adjusting "
315 "thunks for variadic functions");
316 else
317 CGM.ErrorUnsupported(
318 MD, "non-trivial argument copy for return-adjusting thunk");
319 }
320 EmitMustTailThunk(CurGD, AdjustedThisPtr, Callee);
321 return;
322 }
323
324 // Start building CallArgs.
325 CallArgList CallArgs;
326 QualType ThisType = MD->getThisType();
327 CallArgs.add(RValue::get(AdjustedThisPtr), ThisType);
328
329 if (isa<CXXDestructorDecl>(MD))
330 CGM.getCXXABI().adjustCallArgsForDestructorThunk(*this, CurGD, CallArgs);
331
332 #ifndef NDEBUG
333 unsigned PrefixArgs = CallArgs.size() - 1;
334 #endif
335 // Add the rest of the arguments.
336 for (const ParmVarDecl *PD : MD->parameters())
337 EmitDelegateCallArg(CallArgs, PD, SourceLocation());
338
339 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
340
341 #ifndef NDEBUG
342 const CGFunctionInfo &CallFnInfo = CGM.getTypes().arrangeCXXMethodCall(
343 CallArgs, FPT, RequiredArgs::forPrototypePlus(FPT, 1), PrefixArgs);
344 assert(CallFnInfo.getRegParm() == CurFnInfo->getRegParm() &&
345 CallFnInfo.isNoReturn() == CurFnInfo->isNoReturn() &&
346 CallFnInfo.getCallingConvention() == CurFnInfo->getCallingConvention());
347 assert(isa<CXXDestructorDecl>(MD) || // ignore dtor return types
348 similar(CallFnInfo.getReturnInfo(), CallFnInfo.getReturnType(),
349 CurFnInfo->getReturnInfo(), CurFnInfo->getReturnType()));
350 assert(CallFnInfo.arg_size() == CurFnInfo->arg_size());
351 for (unsigned i = 0, e = CurFnInfo->arg_size(); i != e; ++i)
352 assert(similar(CallFnInfo.arg_begin()[i].info,
353 CallFnInfo.arg_begin()[i].type,
354 CurFnInfo->arg_begin()[i].info,
355 CurFnInfo->arg_begin()[i].type));
356 #endif
357
358 // Determine whether we have a return value slot to use.
359 QualType ResultType = CGM.getCXXABI().HasThisReturn(CurGD)
360 ? ThisType
361 : CGM.getCXXABI().hasMostDerivedReturn(CurGD)
362 ? CGM.getContext().VoidPtrTy
363 : FPT->getReturnType();
364 ReturnValueSlot Slot;
365 if (!ResultType->isVoidType() &&
366 CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect)
367 Slot = ReturnValueSlot(ReturnValue, ResultType.isVolatileQualified());
368
369 // Now emit our call.
370 llvm::CallBase *CallOrInvoke;
371 RValue RV = EmitCall(*CurFnInfo, CGCallee::forDirect(Callee, CurGD), Slot,
372 CallArgs, &CallOrInvoke);
373
374 // Consider return adjustment if we have ThunkInfo.
375 if (Thunk && !Thunk->Return.isEmpty())
376 RV = PerformReturnAdjustment(*this, ResultType, RV, *Thunk);
377 else if (llvm::CallInst* Call = dyn_cast<llvm::CallInst>(CallOrInvoke))
378 Call->setTailCallKind(llvm::CallInst::TCK_Tail);
379
380 // Emit return.
381 if (!ResultType->isVoidType() && Slot.isNull())
382 CGM.getCXXABI().EmitReturnFromThunk(*this, RV, ResultType);
383
384 // Disable the final ARC autorelease.
385 AutoreleaseResult = false;
386
387 FinishThunk();
388 }
389
390 void CodeGenFunction::EmitMustTailThunk(GlobalDecl GD,
391 llvm::Value *AdjustedThisPtr,
392 llvm::FunctionCallee Callee) {
393 // Emitting a musttail call thunk doesn't use any of the CGCall.cpp machinery
394 // to translate AST arguments into LLVM IR arguments. For thunks, we know
395 // that the caller prototype more or less matches the callee prototype with
396 // the exception of 'this'.
397 SmallVector<llvm::Value *, 8> Args;
398 for (llvm::Argument &A : CurFn->args())
399 Args.push_back(&A);
400
401 // Set the adjusted 'this' pointer.
402 const ABIArgInfo &ThisAI = CurFnInfo->arg_begin()->info;
403 if (ThisAI.isDirect()) {
404 const ABIArgInfo &RetAI = CurFnInfo->getReturnInfo();
405 int ThisArgNo = RetAI.isIndirect() && !RetAI.isSRetAfterThis() ? 1 : 0;
406 llvm::Type *ThisType = Args[ThisArgNo]->getType();
407 if (ThisType != AdjustedThisPtr->getType())
408 AdjustedThisPtr = Builder.CreateBitCast(AdjustedThisPtr, ThisType);
409 Args[ThisArgNo] = AdjustedThisPtr;
410 } else {
411 assert(ThisAI.isInAlloca() && "this is passed directly or inalloca");
412 Address ThisAddr = GetAddrOfLocalVar(CXXABIThisDecl);
413 llvm::Type *ThisType = ThisAddr.getElementType();
414 if (ThisType != AdjustedThisPtr->getType())
415 AdjustedThisPtr = Builder.CreateBitCast(AdjustedThisPtr, ThisType);
416 Builder.CreateStore(AdjustedThisPtr, ThisAddr);
417 }
418
419 // Emit the musttail call manually. Even if the prologue pushed cleanups, we
420 // don't actually want to run them.
421 llvm::CallInst *Call = Builder.CreateCall(Callee, Args);
422 Call->setTailCallKind(llvm::CallInst::TCK_MustTail);
423
424 // Apply the standard set of call attributes.
425 unsigned CallingConv;
426 llvm::AttributeList Attrs;
427 CGM.ConstructAttributeList(Callee.getCallee()->getName(), *CurFnInfo, GD,
428 Attrs, CallingConv, /*AttrOnCallSite=*/true);
429 Call->setAttributes(Attrs);
430 Call->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
431
432 if (Call->getType()->isVoidTy())
433 Builder.CreateRetVoid();
434 else
435 Builder.CreateRet(Call);
436
437 // Finish the function to maintain CodeGenFunction invariants.
438 // FIXME: Don't emit unreachable code.
439 EmitBlock(createBasicBlock());
440 FinishFunction();
441 }
442
443 void CodeGenFunction::generateThunk(llvm::Function *Fn,
444 const CGFunctionInfo &FnInfo, GlobalDecl GD,
445 const ThunkInfo &Thunk,
446 bool IsUnprototyped) {
447 StartThunk(Fn, GD, FnInfo, IsUnprototyped);
448 // Create a scope with an artificial location for the body of this function.
449 auto AL = ApplyDebugLocation::CreateArtificial(*this);
450
451 // Get our callee. Use a placeholder type if this method is unprototyped so
452 // that CodeGenModule doesn't try to set attributes.
453 llvm::Type *Ty;
454 if (IsUnprototyped)
455 Ty = llvm::StructType::get(getLLVMContext());
456 else
457 Ty = CGM.getTypes().GetFunctionType(FnInfo);
458
459 llvm::Constant *Callee = CGM.GetAddrOfFunction(GD, Ty, /*ForVTable=*/true);
460
461 // Fix up the function type for an unprototyped musttail call.
462 if (IsUnprototyped)
463 Callee = llvm::ConstantExpr::getBitCast(Callee, Fn->getType());
464
465 // Make the call and return the result.
466 EmitCallAndReturnForThunk(llvm::FunctionCallee(Fn->getFunctionType(), Callee),
467 &Thunk, IsUnprototyped);
468 }
469
470 static bool shouldEmitVTableThunk(CodeGenModule &CGM, const CXXMethodDecl *MD,
471 bool IsUnprototyped, bool ForVTable) {
472 // Always emit thunks in the MS C++ ABI. We cannot rely on other TUs to
473 // provide thunks for us.
474 if (CGM.getTarget().getCXXABI().isMicrosoft())
475 return true;
476
477 // In the Itanium C++ ABI, vtable thunks are provided by TUs that provide
478 // definitions of the main method. Therefore, emitting thunks with the vtable
479 // is purely an optimization. Emit the thunk if optimizations are enabled and
480 // all of the parameter types are complete.
481 if (ForVTable)
482 return CGM.getCodeGenOpts().OptimizationLevel && !IsUnprototyped;
483
484 // Always emit thunks along with the method definition.
485 return true;
486 }
487
488 llvm::Constant *CodeGenVTables::maybeEmitThunk(GlobalDecl GD,
489 const ThunkInfo &TI,
490 bool ForVTable) {
491 const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
492
493 // First, get a declaration. Compute the mangled name. Don't worry about
494 // getting the function prototype right, since we may only need this
495 // declaration to fill in a vtable slot.
496 SmallString<256> Name;
497 MangleContext &MCtx = CGM.getCXXABI().getMangleContext();
498 llvm::raw_svector_ostream Out(Name);
499 if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD))
500 MCtx.mangleCXXDtorThunk(DD, GD.getDtorType(), TI.This, Out);
501 else
502 MCtx.mangleThunk(MD, TI, Out);
503 llvm::Type *ThunkVTableTy = CGM.getTypes().GetFunctionTypeForVTable(GD);
504 llvm::Constant *Thunk = CGM.GetAddrOfThunk(Name, ThunkVTableTy, GD);
505
506 // If we don't need to emit a definition, return this declaration as is.
507 bool IsUnprototyped = !CGM.getTypes().isFuncTypeConvertible(
508 MD->getType()->castAs<FunctionType>());
509 if (!shouldEmitVTableThunk(CGM, MD, IsUnprototyped, ForVTable))
510 return Thunk;
511
512 // Arrange a function prototype appropriate for a function definition. In some
513 // cases in the MS ABI, we may need to build an unprototyped musttail thunk.
514 const CGFunctionInfo &FnInfo =
515 IsUnprototyped ? CGM.getTypes().arrangeUnprototypedMustTailThunk(MD)
516 : CGM.getTypes().arrangeGlobalDeclaration(GD);
517 llvm::FunctionType *ThunkFnTy = CGM.getTypes().GetFunctionType(FnInfo);
518
519 // If the type of the underlying GlobalValue is wrong, we'll have to replace
520 // it. It should be a declaration.
521 llvm::Function *ThunkFn = cast<llvm::Function>(Thunk->stripPointerCasts());
522 if (ThunkFn->getFunctionType() != ThunkFnTy) {
523 llvm::GlobalValue *OldThunkFn = ThunkFn;
524
525 assert(OldThunkFn->isDeclaration() && "Shouldn't replace non-declaration");
526
527 // Remove the name from the old thunk function and get a new thunk.
528 OldThunkFn->setName(StringRef());
529 ThunkFn = llvm::Function::Create(ThunkFnTy, llvm::Function::ExternalLinkage,
530 Name.str(), &CGM.getModule());
531 CGM.SetLLVMFunctionAttributes(MD, FnInfo, ThunkFn);
532
533 // If needed, replace the old thunk with a bitcast.
534 if (!OldThunkFn->use_empty()) {
535 llvm::Constant *NewPtrForOldDecl =
536 llvm::ConstantExpr::getBitCast(ThunkFn, OldThunkFn->getType());
537 OldThunkFn->replaceAllUsesWith(NewPtrForOldDecl);
538 }
539
540 // Remove the old thunk.
541 OldThunkFn->eraseFromParent();
542 }
543
544 bool ABIHasKeyFunctions = CGM.getTarget().getCXXABI().hasKeyFunctions();
545 bool UseAvailableExternallyLinkage = ForVTable && ABIHasKeyFunctions;
546
547 if (!ThunkFn->isDeclaration()) {
548 if (!ABIHasKeyFunctions || UseAvailableExternallyLinkage) {
549 // There is already a thunk emitted for this function, do nothing.
550 return ThunkFn;
551 }
552
553 setThunkProperties(CGM, TI, ThunkFn, ForVTable, GD);
554 return ThunkFn;
555 }
556
557 // If this will be unprototyped, add the "thunk" attribute so that LLVM knows
558 // that the return type is meaningless. These thunks can be used to call
559 // functions with differing return types, and the caller is required to cast
560 // the prototype appropriately to extract the correct value.
561 if (IsUnprototyped)
562 ThunkFn->addFnAttr("thunk");
563
564 CGM.SetLLVMFunctionAttributesForDefinition(GD.getDecl(), ThunkFn);
565
566 // Thunks for variadic methods are special because in general variadic
567 // arguments cannot be perferctly forwarded. In the general case, clang
568 // implements such thunks by cloning the original function body. However, for
569 // thunks with no return adjustment on targets that support musttail, we can
570 // use musttail to perfectly forward the variadic arguments.
571 bool ShouldCloneVarArgs = false;
572 if (!IsUnprototyped && ThunkFn->isVarArg()) {
573 ShouldCloneVarArgs = true;
574 if (TI.Return.isEmpty()) {
575 switch (CGM.getTriple().getArch()) {
576 case llvm::Triple::x86_64:
577 case llvm::Triple::x86:
578 case llvm::Triple::aarch64:
579 ShouldCloneVarArgs = false;
580 break;
581 default:
582 break;
583 }
584 }
585 }
586
587 if (ShouldCloneVarArgs) {
588 if (UseAvailableExternallyLinkage)
589 return ThunkFn;
590 ThunkFn =
591 CodeGenFunction(CGM).GenerateVarArgsThunk(ThunkFn, FnInfo, GD, TI);
592 } else {
593 // Normal thunk body generation.
594 CodeGenFunction(CGM).generateThunk(ThunkFn, FnInfo, GD, TI, IsUnprototyped);
595 }
596
597 setThunkProperties(CGM, TI, ThunkFn, ForVTable, GD);
598 return ThunkFn;
599 }
600
601 void CodeGenVTables::EmitThunks(GlobalDecl GD) {
602 const CXXMethodDecl *MD =
603 cast<CXXMethodDecl>(GD.getDecl())->getCanonicalDecl();
604
605 // We don't need to generate thunks for the base destructor.
606 if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base)
607 return;
608
609 const VTableContextBase::ThunkInfoVectorTy *ThunkInfoVector =
610 VTContext->getThunkInfo(GD);
611
612 if (!ThunkInfoVector)
613 return;
614
615 for (const ThunkInfo& Thunk : *ThunkInfoVector)
616 maybeEmitThunk(GD, Thunk, /*ForVTable=*/false);
617 }
618
619 void CodeGenVTables::addVTableComponent(
620 ConstantArrayBuilder &builder, const VTableLayout &layout,
621 unsigned idx, llvm::Constant *rtti, unsigned &nextVTableThunkIndex) {
622 auto &component = layout.vtable_components()[idx];
623
624 auto addOffsetConstant = [&](CharUnits offset) {
625 builder.add(llvm::ConstantExpr::getIntToPtr(
626 llvm::ConstantInt::get(CGM.PtrDiffTy, offset.getQuantity()),
627 CGM.Int8PtrTy));
628 };
629
630 switch (component.getKind()) {
631 case VTableComponent::CK_VCallOffset:
632 return addOffsetConstant(component.getVCallOffset());
633
634 case VTableComponent::CK_VBaseOffset:
635 return addOffsetConstant(component.getVBaseOffset());
636
637 case VTableComponent::CK_OffsetToTop:
638 return addOffsetConstant(component.getOffsetToTop());
639
640 case VTableComponent::CK_RTTI:
641 return builder.add(llvm::ConstantExpr::getBitCast(rtti, CGM.Int8PtrTy));
642
643 case VTableComponent::CK_FunctionPointer:
644 case VTableComponent::CK_CompleteDtorPointer:
645 case VTableComponent::CK_DeletingDtorPointer: {
646 GlobalDecl GD;
647
648 // Get the right global decl.
649 switch (component.getKind()) {
650 default:
651 llvm_unreachable("Unexpected vtable component kind");
652 case VTableComponent::CK_FunctionPointer:
653 GD = component.getFunctionDecl();
654 break;
655 case VTableComponent::CK_CompleteDtorPointer:
656 GD = GlobalDecl(component.getDestructorDecl(), Dtor_Complete);
657 break;
658 case VTableComponent::CK_DeletingDtorPointer:
659 GD = GlobalDecl(component.getDestructorDecl(), Dtor_Deleting);
660 break;
661 }
662
663 if (CGM.getLangOpts().CUDA) {
664 // Emit NULL for methods we can't codegen on this
665 // side. Otherwise we'd end up with vtable with unresolved
666 // references.
667 const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
668 // OK on device side: functions w/ __device__ attribute
669 // OK on host side: anything except __device__-only functions.
670 bool CanEmitMethod =
671 CGM.getLangOpts().CUDAIsDevice
672 ? MD->hasAttr<CUDADeviceAttr>()
673 : (MD->hasAttr<CUDAHostAttr>() || !MD->hasAttr<CUDADeviceAttr>());
674 if (!CanEmitMethod)
675 return builder.addNullPointer(CGM.Int8PtrTy);
676 // Method is acceptable, continue processing as usual.
677 }
678
679 auto getSpecialVirtualFn = [&](StringRef name) -> llvm::Constant * {
680 // For NVPTX devices in OpenMP emit special functon as null pointers,
681 // otherwise linking ends up with unresolved references.
682 if (CGM.getLangOpts().OpenMP && CGM.getLangOpts().OpenMPIsDevice &&
683 CGM.getTriple().isNVPTX())
684 return llvm::ConstantPointerNull::get(CGM.Int8PtrTy);
685 llvm::FunctionType *fnTy =
686 llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
687 llvm::Constant *fn = cast<llvm::Constant>(
688 CGM.CreateRuntimeFunction(fnTy, name).getCallee());
689 if (auto f = dyn_cast<llvm::Function>(fn))
690 f->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
691 return llvm::ConstantExpr::getBitCast(fn, CGM.Int8PtrTy);
692 };
693
694 llvm::Constant *fnPtr;
695
696 // Pure virtual member functions.
697 if (cast<CXXMethodDecl>(GD.getDecl())->isPure()) {
698 if (!PureVirtualFn)
699 PureVirtualFn =
700 getSpecialVirtualFn(CGM.getCXXABI().GetPureVirtualCallName());
701 fnPtr = PureVirtualFn;
702
703 // Deleted virtual member functions.
704 } else if (cast<CXXMethodDecl>(GD.getDecl())->isDeleted()) {
705 if (!DeletedVirtualFn)
706 DeletedVirtualFn =
707 getSpecialVirtualFn(CGM.getCXXABI().GetDeletedVirtualCallName());
708 fnPtr = DeletedVirtualFn;
709
710 // Thunks.
711 } else if (nextVTableThunkIndex < layout.vtable_thunks().size() &&
712 layout.vtable_thunks()[nextVTableThunkIndex].first == idx) {
713 auto &thunkInfo = layout.vtable_thunks()[nextVTableThunkIndex].second;
714
715 nextVTableThunkIndex++;
716 fnPtr = maybeEmitThunk(GD, thunkInfo, /*ForVTable=*/true);
717
718 // Otherwise we can use the method definition directly.
719 } else {
720 llvm::Type *fnTy = CGM.getTypes().GetFunctionTypeForVTable(GD);
721 fnPtr = CGM.GetAddrOfFunction(GD, fnTy, /*ForVTable=*/true);
722 }
723
724 fnPtr = llvm::ConstantExpr::getBitCast(fnPtr, CGM.Int8PtrTy);
725 builder.add(fnPtr);
726 return;
727 }
728
729 case VTableComponent::CK_UnusedFunctionPointer:
730 return builder.addNullPointer(CGM.Int8PtrTy);
731 }
732
733 llvm_unreachable("Unexpected vtable component kind");
734 }
735
736 llvm::Type *CodeGenVTables::getVTableType(const VTableLayout &layout) {
737 SmallVector<llvm::Type *, 4> tys;
738 for (unsigned i = 0, e = layout.getNumVTables(); i != e; ++i) {
739 tys.push_back(llvm::ArrayType::get(CGM.Int8PtrTy, layout.getVTableSize(i)));
740 }
741
742 return llvm::StructType::get(CGM.getLLVMContext(), tys);
743 }
744
745 void CodeGenVTables::createVTableInitializer(ConstantStructBuilder &builder,
746 const VTableLayout &layout,
747 llvm::Constant *rtti) {
748 unsigned nextVTableThunkIndex = 0;
749 for (unsigned i = 0, e = layout.getNumVTables(); i != e; ++i) {
750 auto vtableElem = builder.beginArray(CGM.Int8PtrTy);
751 size_t thisIndex = layout.getVTableOffset(i);
752 size_t nextIndex = thisIndex + layout.getVTableSize(i);
753 for (unsigned i = thisIndex; i != nextIndex; ++i) {
754 addVTableComponent(vtableElem, layout, i, rtti, nextVTableThunkIndex);
755 }
756 vtableElem.finishAndAddTo(builder);
757 }
758 }
759
760 llvm::GlobalVariable *
761 CodeGenVTables::GenerateConstructionVTable(const CXXRecordDecl *RD,
762 const BaseSubobject &Base,
763 bool BaseIsVirtual,
764 llvm::GlobalVariable::LinkageTypes Linkage,
765 VTableAddressPointsMapTy& AddressPoints) {
766 if (CGDebugInfo *DI = CGM.getModuleDebugInfo())
767 DI->completeClassData(Base.getBase());
768
769 std::unique_ptr<VTableLayout> VTLayout(
770 getItaniumVTableContext().createConstructionVTableLayout(
771 Base.getBase(), Base.getBaseOffset(), BaseIsVirtual, RD));
772
773 // Add the address points.
774 AddressPoints = VTLayout->getAddressPoints();
775
776 // Get the mangled construction vtable name.
777 SmallString<256> OutName;
778 llvm::raw_svector_ostream Out(OutName);
779 cast<ItaniumMangleContext>(CGM.getCXXABI().getMangleContext())
780 .mangleCXXCtorVTable(RD, Base.getBaseOffset().getQuantity(),
781 Base.getBase(), Out);
782 StringRef Name = OutName.str();
783
784 llvm::Type *VTType = getVTableType(*VTLayout);
785
786 // Construction vtable symbols are not part of the Itanium ABI, so we cannot
787 // guarantee that they actually will be available externally. Instead, when
788 // emitting an available_externally VTT, we provide references to an internal
789 // linkage construction vtable. The ABI only requires complete-object vtables
790 // to be the same for all instances of a type, not construction vtables.
791 if (Linkage == llvm::GlobalVariable::AvailableExternallyLinkage)
792 Linkage = llvm::GlobalVariable::InternalLinkage;
793
794 unsigned Align = CGM.getDataLayout().getABITypeAlignment(VTType);
795
796 // Create the variable that will hold the construction vtable.
797 llvm::GlobalVariable *VTable =
798 CGM.CreateOrReplaceCXXRuntimeVariable(Name, VTType, Linkage, Align);
799
800 // V-tables are always unnamed_addr.
801 VTable->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
802
803 llvm::Constant *RTTI = CGM.GetAddrOfRTTIDescriptor(
804 CGM.getContext().getTagDeclType(Base.getBase()));
805
806 // Create and set the initializer.
807 ConstantInitBuilder builder(CGM);
808 auto components = builder.beginStruct();
809 createVTableInitializer(components, *VTLayout, RTTI);
810 components.finishAndSetAsInitializer(VTable);
811
812 // Set properties only after the initializer has been set to ensure that the
813 // GV is treated as definition and not declaration.
814 assert(!VTable->isDeclaration() && "Shouldn't set properties on declaration");
815 CGM.setGVProperties(VTable, RD);
816
817 CGM.EmitVTableTypeMetadata(RD, VTable, *VTLayout.get());
818
819 return VTable;
820 }
821
822 static bool shouldEmitAvailableExternallyVTable(const CodeGenModule &CGM,
823 const CXXRecordDecl *RD) {
824 return CGM.getCodeGenOpts().OptimizationLevel > 0 &&
825 CGM.getCXXABI().canSpeculativelyEmitVTable(RD);
826 }
827
828 /// Compute the required linkage of the vtable for the given class.
829 ///
830 /// Note that we only call this at the end of the translation unit.
831 llvm::GlobalVariable::LinkageTypes
832 CodeGenModule::getVTableLinkage(const CXXRecordDecl *RD) {
833 if (!RD->isExternallyVisible())
834 return llvm::GlobalVariable::InternalLinkage;
835
836 // We're at the end of the translation unit, so the current key
837 // function is fully correct.
838 const CXXMethodDecl *keyFunction = Context.getCurrentKeyFunction(RD);
839 if (keyFunction && !RD->hasAttr<DLLImportAttr>()) {
840 // If this class has a key function, use that to determine the
841 // linkage of the vtable.
842 const FunctionDecl *def = nullptr;
843 if (keyFunction->hasBody(def))
844 keyFunction = cast<CXXMethodDecl>(def);
845
846 switch (keyFunction->getTemplateSpecializationKind()) {
847 case TSK_Undeclared:
848 case TSK_ExplicitSpecialization:
849 assert((def || CodeGenOpts.OptimizationLevel > 0 ||
850 CodeGenOpts.getDebugInfo() != codegenoptions::NoDebugInfo) &&
851 "Shouldn't query vtable linkage without key function, "
852 "optimizations, or debug info");
853 if (!def && CodeGenOpts.OptimizationLevel > 0)
854 return llvm::GlobalVariable::AvailableExternallyLinkage;
855
856 if (keyFunction->isInlined())
857 return !Context.getLangOpts().AppleKext ?
858 llvm::GlobalVariable::LinkOnceODRLinkage :
859 llvm::Function::InternalLinkage;
860
861 return llvm::GlobalVariable::ExternalLinkage;
862
863 case TSK_ImplicitInstantiation:
864 return !Context.getLangOpts().AppleKext ?
865 llvm::GlobalVariable::LinkOnceODRLinkage :
866 llvm::Function::InternalLinkage;
867
868 case TSK_ExplicitInstantiationDefinition:
869 return !Context.getLangOpts().AppleKext ?
870 llvm::GlobalVariable::WeakODRLinkage :
871 llvm::Function::InternalLinkage;
872
873 case TSK_ExplicitInstantiationDeclaration:
874 llvm_unreachable("Should not have been asked to emit this");
875 }
876 }
877
878 // -fapple-kext mode does not support weak linkage, so we must use
879 // internal linkage.
880 if (Context.getLangOpts().AppleKext)
881 return llvm::Function::InternalLinkage;
882
883 llvm::GlobalVariable::LinkageTypes DiscardableODRLinkage =
884 llvm::GlobalValue::LinkOnceODRLinkage;
885 llvm::GlobalVariable::LinkageTypes NonDiscardableODRLinkage =
886 llvm::GlobalValue::WeakODRLinkage;
887 if (RD->hasAttr<DLLExportAttr>()) {
888 // Cannot discard exported vtables.
889 DiscardableODRLinkage = NonDiscardableODRLinkage;
890 } else if (RD->hasAttr<DLLImportAttr>()) {
891 // Imported vtables are available externally.
892 DiscardableODRLinkage = llvm::GlobalVariable::AvailableExternallyLinkage;
893 NonDiscardableODRLinkage = llvm::GlobalVariable::AvailableExternallyLinkage;
894 }
895
896 switch (RD->getTemplateSpecializationKind()) {
897 case TSK_Undeclared:
898 case TSK_ExplicitSpecialization:
899 case TSK_ImplicitInstantiation:
900 return DiscardableODRLinkage;
901
902 case TSK_ExplicitInstantiationDeclaration:
903 // Explicit instantiations in MSVC do not provide vtables, so we must emit
904 // our own.
905 if (getTarget().getCXXABI().isMicrosoft())
906 return DiscardableODRLinkage;
907 return shouldEmitAvailableExternallyVTable(*this, RD)
908 ? llvm::GlobalVariable::AvailableExternallyLinkage
909 : llvm::GlobalVariable::ExternalLinkage;
910
911 case TSK_ExplicitInstantiationDefinition:
912 return NonDiscardableODRLinkage;
913 }
914
915 llvm_unreachable("Invalid TemplateSpecializationKind!");
916 }
917
918 /// This is a callback from Sema to tell us that a particular vtable is
919 /// required to be emitted in this translation unit.
920 ///
921 /// This is only called for vtables that _must_ be emitted (mainly due to key
922 /// functions). For weak vtables, CodeGen tracks when they are needed and
923 /// emits them as-needed.
924 void CodeGenModule::EmitVTable(CXXRecordDecl *theClass) {
925 VTables.GenerateClassData(theClass);
926 }
927
928 void
929 CodeGenVTables::GenerateClassData(const CXXRecordDecl *RD) {
930 if (CGDebugInfo *DI = CGM.getModuleDebugInfo())
931 DI->completeClassData(RD);
932
933 if (RD->getNumVBases())
934 CGM.getCXXABI().emitVirtualInheritanceTables(RD);
935
936 CGM.getCXXABI().emitVTableDefinitions(*this, RD);
937 }
938
939 /// At this point in the translation unit, does it appear that can we
940 /// rely on the vtable being defined elsewhere in the program?
941 ///
942 /// The response is really only definitive when called at the end of
943 /// the translation unit.
944 ///
945 /// The only semantic restriction here is that the object file should
946 /// not contain a vtable definition when that vtable is defined
947 /// strongly elsewhere. Otherwise, we'd just like to avoid emitting
948 /// vtables when unnecessary.
949 bool CodeGenVTables::isVTableExternal(const CXXRecordDecl *RD) {
950 assert(RD->isDynamicClass() && "Non-dynamic classes have no VTable.");
951
952 // We always synthesize vtables if they are needed in the MS ABI. MSVC doesn't
953 // emit them even if there is an explicit template instantiation.
954 if (CGM.getTarget().getCXXABI().isMicrosoft())
955 return false;
956
957 // If we have an explicit instantiation declaration (and not a
958 // definition), the vtable is defined elsewhere.
959 TemplateSpecializationKind TSK = RD->getTemplateSpecializationKind();
960 if (TSK == TSK_ExplicitInstantiationDeclaration)
961 return true;
962
963 // Otherwise, if the class is an instantiated template, the
964 // vtable must be defined here.
965 if (TSK == TSK_ImplicitInstantiation ||
966 TSK == TSK_ExplicitInstantiationDefinition)
967 return false;
968
969 // Otherwise, if the class doesn't have a key function (possibly
970 // anymore), the vtable must be defined here.
971 const CXXMethodDecl *keyFunction = CGM.getContext().getCurrentKeyFunction(RD);
972 if (!keyFunction)
973 return false;
974
975 // Otherwise, if we don't have a definition of the key function, the
976 // vtable must be defined somewhere else.
977 return !keyFunction->hasBody();
978 }
979
980 /// Given that we're currently at the end of the translation unit, and
981 /// we've emitted a reference to the vtable for this class, should
982 /// we define that vtable?
983 static bool shouldEmitVTableAtEndOfTranslationUnit(CodeGenModule &CGM,
984 const CXXRecordDecl *RD) {
985 // If vtable is internal then it has to be done.
986 if (!CGM.getVTables().isVTableExternal(RD))
987 return true;
988
989 // If it's external then maybe we will need it as available_externally.
990 return shouldEmitAvailableExternallyVTable(CGM, RD);
991 }
992
993 /// Given that at some point we emitted a reference to one or more
994 /// vtables, and that we are now at the end of the translation unit,
995 /// decide whether we should emit them.
996 void CodeGenModule::EmitDeferredVTables() {
997 #ifndef NDEBUG
998 // Remember the size of DeferredVTables, because we're going to assume
999 // that this entire operation doesn't modify it.
1000 size_t savedSize = DeferredVTables.size();
1001 #endif
1002
1003 for (const CXXRecordDecl *RD : DeferredVTables)
1004 if (shouldEmitVTableAtEndOfTranslationUnit(*this, RD))
1005 VTables.GenerateClassData(RD);
1006 else if (shouldOpportunisticallyEmitVTables())
1007 OpportunisticVTables.push_back(RD);
1008
1009 assert(savedSize == DeferredVTables.size() &&
1010 "deferred extra vtables during vtable emission?");
1011 DeferredVTables.clear();
1012 }
1013
1014 bool CodeGenModule::HasHiddenLTOVisibility(const CXXRecordDecl *RD) {
1015 LinkageInfo LV = RD->getLinkageAndVisibility();
1016 if (!isExternallyVisible(LV.getLinkage()))
1017 return true;
1018
1019 if (RD->hasAttr<LTOVisibilityPublicAttr>() || RD->hasAttr<UuidAttr>())
1020 return false;
1021
1022 if (getTriple().isOSBinFormatCOFF()) {
1023 if (RD->hasAttr<DLLExportAttr>() || RD->hasAttr<DLLImportAttr>())
1024 return false;
1025 } else {
1026 if (LV.getVisibility() != HiddenVisibility)
1027 return false;
1028 }
1029
1030 if (getCodeGenOpts().LTOVisibilityPublicStd) {
1031 const DeclContext *DC = RD;
1032 while (1) {
1033 auto *D = cast<Decl>(DC);
1034 DC = DC->getParent();
1035 if (isa<TranslationUnitDecl>(DC->getRedeclContext())) {
1036 if (auto *ND = dyn_cast<NamespaceDecl>(D))
1037 if (const IdentifierInfo *II = ND->getIdentifier())
1038 if (II->isStr("std") || II->isStr("stdext"))
1039 return false;
1040 break;
1041 }
1042 }
1043 }
1044
1045 return true;
1046 }
1047
1048 llvm::GlobalObject::VCallVisibility
1049 CodeGenModule::GetVCallVisibilityLevel(const CXXRecordDecl *RD) {
1050 LinkageInfo LV = RD->getLinkageAndVisibility();
1051 llvm::GlobalObject::VCallVisibility TypeVis;
1052 if (!isExternallyVisible(LV.getLinkage()))
1053 TypeVis = llvm::GlobalObject::VCallVisibilityTranslationUnit;
1054 else if (HasHiddenLTOVisibility(RD))
1055 TypeVis = llvm::GlobalObject::VCallVisibilityLinkageUnit;
1056 else
1057 TypeVis = llvm::GlobalObject::VCallVisibilityPublic;
1058
1059 for (auto B : RD->bases())
1060 if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
1061 TypeVis = std::min(TypeVis,
1062 GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
1063
1064 for (auto B : RD->vbases())
1065 if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
1066 TypeVis = std::min(TypeVis,
1067 GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
1068
1069 return TypeVis;
1070 }
1071
1072 void CodeGenModule::EmitVTableTypeMetadata(const CXXRecordDecl *RD,
1073 llvm::GlobalVariable *VTable,
1074 const VTableLayout &VTLayout) {
1075 if (!getCodeGenOpts().LTOUnit)
1076 return;
1077
1078 CharUnits PointerWidth =
1079 Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
1080
1081 typedef std::pair<const CXXRecordDecl *, unsigned> AddressPoint;
1082 std::vector<AddressPoint> AddressPoints;
1083 for (auto &&AP : VTLayout.getAddressPoints())
1084 AddressPoints.push_back(std::make_pair(
1085 AP.first.getBase(), VTLayout.getVTableOffset(AP.second.VTableIndex) +
1086 AP.second.AddressPointIndex));
1087
1088 // Sort the address points for determinism.
1089 llvm::sort(AddressPoints, [this](const AddressPoint &AP1,
1090 const AddressPoint &AP2) {
1091 if (&AP1 == &AP2)
1092 return false;
1093
1094 std::string S1;
1095 llvm::raw_string_ostream O1(S1);
1096 getCXXABI().getMangleContext().mangleTypeName(
1097 QualType(AP1.first->getTypeForDecl(), 0), O1);
1098 O1.flush();
1099
1100 std::string S2;
1101 llvm::raw_string_ostream O2(S2);
1102 getCXXABI().getMangleContext().mangleTypeName(
1103 QualType(AP2.first->getTypeForDecl(), 0), O2);
1104 O2.flush();
1105
1106 if (S1 < S2)
1107 return true;
1108 if (S1 != S2)
1109 return false;
1110
1111 return AP1.second < AP2.second;
1112 });
1113
1114 ArrayRef<VTableComponent> Comps = VTLayout.vtable_components();
1115 for (auto AP : AddressPoints) {
1116 // Create type metadata for the address point.
1117 AddVTableTypeMetadata(VTable, PointerWidth * AP.second, AP.first);
1118
1119 // The class associated with each address point could also potentially be
1120 // used for indirect calls via a member function pointer, so we need to
1121 // annotate the address of each function pointer with the appropriate member
1122 // function pointer type.
1123 for (unsigned I = 0; I != Comps.size(); ++I) {
1124 if (Comps[I].getKind() != VTableComponent::CK_FunctionPointer)
1125 continue;
1126 llvm::Metadata *MD = CreateMetadataIdentifierForVirtualMemPtrType(
1127 Context.getMemberPointerType(
1128 Comps[I].getFunctionDecl()->getType(),
1129 Context.getRecordType(AP.first).getTypePtr()));
1130 VTable->addTypeMetadata((PointerWidth * I).getQuantity(), MD);
1131 }
1132 }
1133
1134 if (getCodeGenOpts().VirtualFunctionElimination) {
1135 llvm::GlobalObject::VCallVisibility TypeVis = GetVCallVisibilityLevel(RD);
1136 if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
1137 VTable->addVCallVisibilityMetadata(TypeVis);
1138 }
1139 }
clang::CodeGen::CodeGenModule::getDataLayout
const llvm::DataLayout & getDataLayout() const
Definition: CodeGenModule.h:683
clang::VTableLayout::getNumVTables
size_t getNumVTables() const
Definition: VTableBuilder.h:280
clang::CodeGen::ReturnValueSlot
ReturnValueSlot - Contains the address where the return value of a function can be stored...
Definition: CGCall.h:359
getCanonicalDecl
static const Decl * getCanonicalDecl(const Decl *D)
Definition: IndexingContext.cpp:292
clang::FunctionDecl
Represents a function declaration or definition.
Definition: Decl.h:1783
clang::ExternalLinkage
External linkage, which indicates that the entity can be referred to from other translation units...
Definition: Linkage.h:59
clang::CodeGen::CodeGenModule::SetLLVMFunctionAttributes
void SetLLVMFunctionAttributes(GlobalDecl GD, const CGFunctionInfo &Info, llvm::Function *F)
Set the LLVM function attributes (sext, zext, etc).
Definition: CodeGenModule.cpp:1232
clang::ASTContext::VoidPtrTy
CanQualType VoidPtrTy
Definition: ASTContext.h:1044
clang::QualType
A (possibly-)qualified type.
Definition: Type.h:654
clang::CodeGen::CodeGenModule::ReturnTypeUsesSRet
bool ReturnTypeUsesSRet(const CGFunctionInfo &FI)
Return true iff the given type uses &#39;sret&#39; when used as a return type.
Definition: CGCall.cpp:1512
clang::CodeGen::CodeGenModule::getTypes
CodeGenTypes & getTypes()
Definition: CodeGenModule.h:698
clang::CXXRecordDecl::bases
base_class_range bases()
Definition: DeclCXX.h:587
clang::CodeGen::CodeGenModule::getCodeGenOpts
const CodeGenOptions & getCodeGenOpts() const
Definition: CodeGenModule.h:680
clang::VTableLayout::getAddressPoints
const AddressPointsMapTy & getAddressPoints() const
Definition: VTableBuilder.h:276
clang::CodeGen::CGCXXABI::EmitReturnFromThunk
virtual void EmitReturnFromThunk(CodeGenFunction &CGF, RValue RV, QualType ResultType)
Definition: CGCXXABI.cpp:157
clang::CodeGen::CodeGenModule::getLLVMContext
llvm::LLVMContext & getLLVMContext()
Definition: CodeGenModule.h:692
clang::GlobalDecl::getDtorType
CXXDtorType getDtorType() const
Definition: GlobalDecl.h:84
clang::CodeGen::CGCXXABI::addImplicitStructorParams
virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy, FunctionArgList &Params)=0
Insert any ABI-specific implicit parameters into the parameter list for a function.
clang::CodeGen::ConstantInitBuilder
The standard implementation of ConstantInitBuilder used in Clang.
Definition: ConstantInitBuilder.h:516
clang::CodeGen::CodeGenModule::getClassPointerAlignment
CharUnits getClassPointerAlignment(const CXXRecordDecl *CD)
Returns the assumed alignment of an opaque pointer to the given class.
Definition: CGClass.cpp:37
clang::CodeGen::CGFunctionInfo::isVariadic
bool isVariadic() const
Definition: CGFunctionInfo.h:580
clang::FunctionType
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3422
clang::Type::getPointeeType
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:557
clang::CXXRecordDecl::getNumVBases
unsigned getNumVBases() const
Retrieves the number of virtual base classes of this class.
Definition: DeclCXX.h:602
Base
clang::CXXMethodDecl::getThisType
QualType getThisType() const
Return the type of the this pointer.
Definition: DeclCXX.cpp:2328
clang::ReturnAdjustment::isEmpty
bool isEmpty() const
Definition: ABI.h:86
clang::VTableContextBase::getThunkInfo
virtual const ThunkInfoVectorTy * getThunkInfo(GlobalDecl GD)
Definition: VTableBuilder.h:329
clang::CodeGen::CGCXXABI::performThisAdjustment
virtual llvm::Value * performThisAdjustment(CodeGenFunction &CGF, Address This, const ThisAdjustment &TA)=0
clang::LinkageInfo
Definition: Visibility.h:52
clang::CodeGen::CodeGenModule::setFunctionLinkage
void setFunctionLinkage(GlobalDecl GD, llvm::Function *F)
Definition: CodeGenModule.h:1183
CXXInheritance.h
clang::CodeGen::CGCXXABI::GetDeletedVirtualCallName
virtual StringRef GetDeletedVirtualCallName()=0
Gets the deleted virtual member call name.
clang::ASTContext::getTargetInfo
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:707
clang::CodeGen::CodeGenFunction::GenerateVarArgsThunk
llvm::Function * GenerateVarArgsThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo, GlobalDecl GD, const ThunkInfo &Thunk)
Definition: CGVTables.cpp:157
clang::CodeGen::CodeGenTypes::isFuncTypeConvertible
bool isFuncTypeConvertible(const FunctionType *FT)
isFuncTypeConvertible - Utility to check whether a function type can be converted to an LLVM type (i...
Definition: CodeGenTypes.cpp:228
clang::CodeGen::CodeGenModule::HasHiddenLTOVisibility
bool HasHiddenLTOVisibility(const CXXRecordDecl *RD)
Returns whether the given record has hidden LTO visibility and therefore may participate in (single-m...
Definition: CGVTables.cpp:1014
clang::FunctionDecl::isDefined
bool isDefined(const FunctionDecl *&Definition) const
Returns true if the function has a definition that does not need to be instantiated.
Definition: Decl.cpp:2883
clang::CodeGen::CodeGenFunction::StartThunk
void StartThunk(llvm::Function *Fn, GlobalDecl GD, const CGFunctionInfo &FnInfo, bool IsUnprototyped)
Definition: CGVTables.cpp:236
Value
Value
Definition: UninitializedValues.cpp:101
clang::VTableComponent::CK_VCallOffset
Definition: VTableBuilder.h:32
clang::interp::ReturnValue
bool ReturnValue(const T &V, APValue &R)
Convers a value to an APValue.
Definition: Interp.h:41
clang::HiddenVisibility
Objects with "hidden" visibility are not seen by the dynamic linker.
Definition: Visibility.h:36
clang::LinkageInfo::getVisibility
Visibility getVisibility() const
Definition: Visibility.h:84
clang::CodeGen::CodeGenModule::getModuleDebugInfo
CGDebugInfo * getModuleDebugInfo()
Definition: CodeGenModule.h:666
clang::CodeGen::CodeGenModule::supportsCOMDAT
bool supportsCOMDAT() const
Definition: TargetInfo.cpp:9779
clang::CodeGen::CGDebugInfo
This class gathers all debug information during compilation and is responsible for emitting to llvm g...
Definition: CGDebugInfo.h:54
clang::ASTContext::getMemberPointerType
QualType getMemberPointerType(QualType T, const Type *Cls) const
Return the uniqued reference to the type for a member pointer to the specified type in the specified ...
Definition: ASTContext.cpp:3295
clang::CodeGen::Address::getPointer
llvm::Value * getPointer() const
Definition: Address.h:37
clang::codegenoptions::NoDebugInfo
Don&#39;t generate debug info.
Definition: DebugInfoOptions.h:22
clang::ParmVarDecl
Represents a parameter to a function.
Definition: Decl.h:1595
clang::Linkage
Linkage
Describes the different kinds of linkage (C++ [basic.link], C99 6.2.2) that an entity may have...
Definition: Linkage.h:23
clang::CodeGen::CallArgList::add
void add(RValue rvalue, QualType type)
Definition: CGCall.h:285
clang::BaseSubobject::getBaseOffset
CharUnits getBaseOffset() const
getBaseOffset - Returns the base class offset.
Definition: BaseSubobject.h:46
clang::TargetInfo::getPointerWidth
uint64_t getPointerWidth(unsigned AddrSpace) const
Return the width of pointers on this target, for the specified address space.
Definition: TargetInfo.h:361
clang::IdentifierInfo
One of these records is kept for each identifier that is lexed.
Definition: IdentifierTable.h:57
clang::TargetInfo::getCXXABI
TargetCXXABI getCXXABI() const
Get the C++ ABI currently in use.
Definition: TargetInfo.h:1063
clang::CodeGen::CodeGenFunction::generateThunk
void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo, GlobalDecl GD, const ThunkInfo &Thunk, bool IsUnprototyped)
Generate a thunk for the given method.
Definition: CGVTables.cpp:443
clang::CodeGen::ABIArgInfo::Indirect
Indirect - Pass the argument indirectly via a hidden pointer with the specified alignment (0 indicate...
Definition: CGFunctionInfo.h:49
clang::CodeGen::CodeGenFunction
CodeGenFunction - This class organizes the per-function state that is used while generating LLVM code...
Definition: CodeGenFunction.h:227
shouldEmitAvailableExternallyVTable
static bool shouldEmitAvailableExternallyVTable(const CodeGenModule &CGM, const CXXRecordDecl *RD)
Definition: CGVTables.cpp:822
clang::Type::isReferenceType
bool isReferenceType() const
Definition: Type.h:6516
resolveTopLevelMetadata
static void resolveTopLevelMetadata(llvm::Function *Fn, llvm::ValueToValueMapTy &VMap)
This function clones a function&#39;s DISubprogram node and enters it into a value map with the intent th...
Definition: CGVTables.cpp:118
clang::CodeGen::CodeGenFunction::Builder
CGBuilderTy Builder
Definition: CodeGenFunction.h:263
clang::CodeGen::CodeGenVTables::getVTableType
llvm::Type * getVTableType(const VTableLayout &layout)
Returns the type of a vtable with the given layout.
Definition: CGVTables.cpp:736
clang::ThunkInfo
The this pointer adjustment as well as an optional return adjustment for a thunk. ...
Definition: ABI.h:178
clang::CodeGen::ABIArgInfo::isInAlloca
bool isInAlloca() const
Definition: CGFunctionInfo.h:256
clang::CodeGen::ApplyDebugLocation::CreateArtificial
static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF)
Apply TemporaryLocation if it is valid.
Definition: CGDebugInfo.h:769
clang::FunctionDecl::parameters
ArrayRef< ParmVarDecl * > parameters() const
Definition: Decl.h:2399
clang::VTableComponent::CK_RTTI
Definition: VTableBuilder.h:35
clang::CodeGen::CGCXXABI::EmitInstanceFunctionProlog
virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF)=0
Emit the ABI-specific prolog for the function.
clang::VTableLayout::vtable_components
ArrayRef< VTableComponent > vtable_components() const
Definition: VTableBuilder.h:263
clang::CodeGen::CGCXXABI::emitVTableDefinitions
virtual void emitVTableDefinitions(CodeGenVTables &CGVT, const CXXRecordDecl *RD)=0
Emits the VTable definitions required for the given record type.
clang::CharUnits
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:38
clang::Dtor_Deleting
Deleting dtor.
Definition: ABI.h:34
clang::CodeGen::CGCXXABI::hasMostDerivedReturn
virtual bool hasMostDerivedReturn(GlobalDecl GD) const
Definition: CGCXXABI.h:108
clang::VTableComponent::CK_VBaseOffset
Definition: VTableBuilder.h:33
clang::QualType::isVolatileQualified
bool isVolatileQualified() const
Determine whether this type is volatile-qualified.
Definition: Type.h:6326
clang::CodeGen::CodeGenModule::ConstructAttributeList
void ConstructAttributeList(StringRef Name, const CGFunctionInfo &Info, CGCalleeInfo CalleeInfo, llvm::AttributeList &Attrs, unsigned &CallingConv, bool AttrOnCallSite)
Get the LLVM attributes and calling convention to use for a particular function type.
Definition: CGCall.cpp:1836
clang::transformer::name
RangeSelector name(std::string ID)
Given a node with a "name", (like NamedDecl, DeclRefExpr or CxxCtorInitializer) selects the name&#39;s to...
Definition: RangeSelector.cpp:186
clang::CodeGen::ABIArgInfo
ABIArgInfo - Helper class to encapsulate information about how a specific C type should be passed to ...
Definition: CGFunctionInfo.h:32
clang::CodeGen::CGCXXABI::canSpeculativelyEmitVTable
virtual bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const =0
Determine whether it&#39;s possible to emit a vtable for RD, even though we do not know that the vtable h...
clang::QualType::getTypePtr
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:6256
clang::CodeGen::CodeGenFunction::createBasicBlock
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
Definition: CodeGenFunction.h:2071
clang::CodeGen::CodeGenVTables::getItaniumVTableContext
ItaniumVTableContext & getItaniumVTableContext()
Definition: CGVTables.h:78
CGFunctionInfo.h
clang::CodeGen::CodeGenTypeCache::VoidTy
llvm::Type * VoidTy
void
Definition: CodeGenTypeCache.h:34
llvm::ArrayRef
Definition: LLVM.h:31
llvm::SmallString
Definition: LLVM.h:34
shouldEmitVTableThunk
static bool shouldEmitVTableThunk(CodeGenModule &CGM, const CXXMethodDecl *MD, bool IsUnprototyped, bool ForVTable)
Definition: CGVTables.cpp:470
clang::CodeGen::CodeGenTypes::arrangeGlobalDeclaration
const CGFunctionInfo & arrangeGlobalDeclaration(GlobalDecl GD)
Definition: CGCall.cpp:513
clang::FunctionDecl::param_begin
param_iterator param_begin()
Definition: Decl.h:2411
clang::Decl::hasAttr
bool hasAttr() const
Definition: DeclBase.h:542
clang::Type::getAsCXXRecordDecl
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1690
clang::FunctionProtoType
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3754
clang::CXXRecordDecl::isDynamicClass
bool isDynamicClass() const
Definition: DeclCXX.h:553
clang::CodeGen::ConstantAggregateBuilderTemplateBase::beginArray
ArrayBuilder beginArray(llvm::Type *eltTy=nullptr)
Definition: ConstantInitBuilder.h:343
clang::CXXRecordDecl::getTemplateSpecializationKind
TemplateSpecializationKind getTemplateSpecializationKind() const
Determine whether this particular class is a specialization or instantiation of a class template or m...
Definition: DeclCXX.cpp:1700
clang::CodeGen::RValue
RValue - This trivial value class is used to represent the result of an expression that is evaluated...
Definition: CGValue.h:39
clang::CharUnits::getQuantity
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:179
clang::CodeGen::CodeGenVTables::isVTableExternal
bool isVTableExternal(const CXXRecordDecl *RD)
At this point in the translation unit, does it appear that can we rely on the vtable being defined el...
Definition: CGVTables.cpp:949
clang::CodeGen::CGCXXABI::HasThisReturn
virtual bool HasThisReturn(GlobalDecl GD) const
Returns true if the given constructor or destructor is one of the kinds that the ABI says returns &#39;th...
Definition: CGCXXABI.h:106
clang::TargetCXXABI::hasKeyFunctions
bool hasKeyFunctions() const
Does this ABI use key functions? If so, class data such as the vtable is emitted with strong linkage ...
Definition: TargetCXXABI.h:235
setThunkProperties
static void setThunkProperties(CodeGenModule &CGM, const ThunkInfo &Thunk, llvm::Function *ThunkFn, bool ForVTable, GlobalDecl GD)
Definition: CGVTables.cpp:40
similar
static bool similar(const ABIArgInfo &infoL, CanQualType typeL, const ABIArgInfo &infoR, CanQualType typeR)
Definition: CGVTables.cpp:60
CodeGenModule.h
clang::VTableComponent::CK_FunctionPointer
Definition: VTableBuilder.h:36
clang::Type::castAs
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:7067
clang::CodeGen::CGCallee::forDirect
static CGCallee forDirect(llvm::Constant *functionPtr, const CGCalleeInfo &abstractInfo=CGCalleeInfo())
Definition: CGCall.h:133
clang::CXXDestructorDecl
Represents a C++ destructor within a class.
Definition: DeclCXX.h:2649
clang::CodeGen::CGCXXABI::exportThunk
virtual bool exportThunk()=0
clang::ASTContext::getTagDeclType
QualType getTagDeclType(const TagDecl *Decl) const
Return the unique reference to the type for the specified TagDecl (struct/union/class/enum) decl...
Definition: ASTContext.cpp:5244
clang::CodeGen::CGCXXABI::GetPureVirtualCallName
virtual StringRef GetPureVirtualCallName()=0
Gets the pure virtual member call function.
CGCXXABI.h
clang::LinkageInfo::getLinkage
Linkage getLinkage() const
Definition: Visibility.h:83
clang::BaseSubobject::getBase
const CXXRecordDecl * getBase() const
getBase - Returns the base class declaration.
Definition: BaseSubobject.h:43
clang::CodeGen::ABIArgInfo::isDirect
bool isDirect() const
Definition: CGFunctionInfo.h:255
clang::FunctionDecl::hasBody
bool hasBody(const FunctionDecl *&Definition) const
Returns true if the function has a body.
Definition: Decl.cpp:2859
clang::Dtor_Base
Base object dtor.
Definition: ABI.h:36
clang::CodeGen::ABIArgInfo::isIndirect
bool isIndirect() const
Definition: CGFunctionInfo.h:259
clang::BaseSubobject
Definition: BaseSubobject.h:30
clang::CodeGen::CodeGenTypes::arrangeUnprototypedMustTailThunk
const CGFunctionInfo & arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD)
Arrange a thunk that takes &#39;this&#39; as the first parameter followed by varargs.
Definition: CGCall.cpp:530
clang::DeclContext::getParent
DeclContext * getParent()
getParent - Returns the containing DeclContext.
Definition: DeclBase.h:1784
clang::CodeGen::CodeGenFunction::EmitCallAndReturnForThunk
void EmitCallAndReturnForThunk(llvm::FunctionCallee Callee, const ThunkInfo *Thunk, bool IsUnprototyped)
Definition: CGVTables.cpp:292
clang::isExternallyVisible
bool isExternallyVisible(Linkage L)
Definition: Linkage.h:91
clang::ASTContext::getRecordType
QualType getRecordType(const RecordDecl *Decl) const
Definition: ASTContext.cpp:4173
clang::CodeGen::CodeGenModule::getTarget
const TargetInfo & getTarget() const
Definition: CodeGenModule.h:686
clang::TSK_ImplicitInstantiation
This template specialization was implicitly instantiated from a template.
Definition: Specifiers.h:181
clang::CodeGen::CodeGenModule::getLangOpts
const LangOptions & getLangOpts() const
Definition: CodeGenModule.h:675
clang::CodeGen::CodeGenModule::getContext
ASTContext & getContext() const
Definition: CodeGenModule.h:674
clang::CodeGen::CGCXXABI::adjustCallArgsForDestructorThunk
virtual void adjustCallArgsForDestructorThunk(CodeGenFunction &CGF, GlobalDecl GD, CallArgList &CallArgs)
Definition: CGCXXABI.h:434
CodeGenFunction.h
clang::CallingConv
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:265
clang::GlobalDecl
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:40
clang::CodeGen::ABIArgInfo::getKind
Kind getKind() const
Definition: CGFunctionInfo.h:254
clang::CodeGen::AlignmentSource::Type
The l-value was considered opaque, so the alignment was determined from a type.
clang::VTableLayout::vtable_thunks
ArrayRef< VTableThunkTy > vtable_thunks() const
Definition: VTableBuilder.h:267
clang::MangleContext::mangleCXXDtorThunk
virtual void mangleCXXDtorThunk(const CXXDestructorDecl *DD, CXXDtorType Type, const ThisAdjustment &ThisAdjustment, raw_ostream &)=0
Attr.h
clang::CodeGen::CodeGenModule::GetAddrOfThunk
llvm::Constant * GetAddrOfThunk(StringRef Name, llvm::Type *FnTy, GlobalDecl GD)
Get the address of the thunk for the given global decl.
Definition: CGVTables.cpp:34
clang::SourceLocation
Encodes a location in the source.
Definition: SourceLocation.h:86
clang::FunctionType::getReturnType
QualType getReturnType() const
Definition: Type.h:3680
clang::CodeGen::ABIArgInfo::isSRetAfterThis
bool isSRetAfterThis() const
Definition: CGFunctionInfo.h:365
clang::CodeGen::CodeGenModule::setGVProperties
void setGVProperties(llvm::GlobalValue *GV, GlobalDecl GD) const
Set visibility, dllimport/dllexport and dso_local.
Definition: CodeGenModule.cpp:895
clang::GlobalDecl::getDecl
const Decl * getDecl() const
Definition: GlobalDecl.h:77
clang::MangleContext
MangleContext - Context for tracking state which persists across multiple calls to the C++ name mangl...
Definition: Mangle.h:43
clang::CXXMethodDecl
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:1931
clang::CodeGen::CodeGenModule::GetAddrOfRTTIDescriptor
llvm::Constant * GetAddrOfRTTIDescriptor(QualType Ty, bool ForEH=false)
Get the address of the RTTI descriptor for the given type.
Definition: CodeGenModule.cpp:5772
clang::CodeGen::CodeGenVTables::CodeGenVTables
CodeGenVTables(CodeGenModule &CGM)
Definition: CGVTables.cpp:31
clang::CanQual< Type >
clang::ASTContext::VoidTy
CanQualType VoidTy
Definition: ASTContext.h:1016
clang::CodeGen::CodeGenVTables::createVTableInitializer
void createVTableInitializer(ConstantStructBuilder &builder, const VTableLayout &layout, llvm::Constant *rtti)
Add vtable components for the given vtable layout to the given global initializer.
Definition: CGVTables.cpp:745
llvm::SmallVector< llvm::Value *, 8 >
clang::CodeGen::Address
An aligned address.
Definition: Address.h:24
clang::CodeGen::CodeGenModule::SetLLVMFunctionAttributesForDefinition
void SetLLVMFunctionAttributesForDefinition(const Decl *D, llvm::Function *F)
Set the LLVM function attributes which only apply to a function definition.
Definition: CodeGenModule.cpp:1496
clang::CodeGen::CGCXXABI::emitVirtualInheritanceTables
virtual void emitVirtualInheritanceTables(const CXXRecordDecl *RD)=0
Emit any tables needed to implement virtual inheritance.
clang::CodeGen::CGCXXABI::getMangleContext
MangleContext & getMangleContext()
Gets the mangle context.
Definition: CGCXXABI.h:96
clang::TSK_ExplicitInstantiationDefinition
This template specialization was instantiated from a template due to an explicit instantiation defini...
Definition: Specifiers.h:193
clang::TSK_Undeclared
This template specialization was formed from a template-id but has not yet been declared, defined, or instantiated.
Definition: Specifiers.h:178
clang::Dtor_Complete
Complete object dtor.
Definition: ABI.h:35
clang::CodeGen::CodeGenVTables::GenerateConstructionVTable
llvm::GlobalVariable * GenerateConstructionVTable(const CXXRecordDecl *RD, const BaseSubobject &Base, bool BaseIsVirtual, llvm::GlobalVariable::LinkageTypes Linkage, VTableAddressPointsMapTy &AddressPoints)
GenerateConstructionVTable - Generate a construction vtable for the given base subobject.
Definition: CGVTables.cpp:761
clang::CodeGen::FunctionArgList
FunctionArgList - Type for representing both the decl and type of parameters to a function...
Definition: CGCall.h:355
clang::CodeGen::RValue::getScalarVal
llvm::Value * getScalarVal() const
getScalarVal() - Return the Value* of this scalar value.
Definition: CGValue.h:59
clang::CodeGen::CodeGenModule::ErrorUnsupported
void ErrorUnsupported(const Stmt *S, const char *Type)
Print out an error that codegen doesn&#39;t support the specified stmt yet.
Definition: CodeGenModule.cpp:751
clang::CodeGen::CGFunctionInfo
CGFunctionInfo - Class to encapsulate the information about a function definition.
Definition: CGFunctionInfo.h:476
clang::CodeGen::CodeGenModule
This class organizes the cross-function state that is used while generating LLVM code.
Definition: CodeGenModule.h:280
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:21
clang::CodeGen::ReturnValueSlot::isNull
bool isNull() const
Definition: CGCall.h:376
clang::ThunkInfo::This
ThisAdjustment This
The this pointer adjustment.
Definition: ABI.h:180
clang::DeclContext
DeclContext - This is used only as base class of specific decl types that can act as declaration cont...
Definition: DeclBase.h:1271
clang::FunctionDecl::getTemplateSpecializationKind
TemplateSpecializationKind getTemplateSpecializationKind() const
Determine what kind of template instantiation this function represents.
Definition: Decl.cpp:3756
CodeGenOptions.h
clang::TSK_ExplicitInstantiationDeclaration
This template specialization was instantiated from a template due to an explicit instantiation declar...
Definition: Specifiers.h:189
clang::CodeGen::CodeGenFunction::FinishThunk
void FinishThunk()
Definition: CGVTables.cpp:283
clang::CXXMethodDecl::getParent
const CXXRecordDecl * getParent() const
Return the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2046
clang::CodeGen::CGCXXABI::buildThisParam
void buildThisParam(CodeGenFunction &CGF, FunctionArgList &Params)
Build a parameter variable suitable for &#39;this&#39;.
Definition: CGCXXABI.cpp:122
clang::CodeGen::CodeGenModule::CreateRuntimeFunction
llvm::FunctionCallee CreateRuntimeFunction(llvm::FunctionType *Ty, StringRef Name, llvm::AttributeList ExtraAttrs=llvm::AttributeList(), bool Local=false, bool AssumeConvergent=false)
Create or return a runtime function declaration with the specified type and name. ...
Definition: CodeGenModule.cpp:3366
clang::TemplateSpecializationKind
TemplateSpecializationKind
Describes the kind of template specialization that a particular template specialization declaration r...
Definition: Specifiers.h:175
clang::CodeGen::CodeGenModule::getModule
llvm::Module & getModule() const
Definition: CodeGenModule.h:681
clang::VTableComponent::CK_OffsetToTop
Definition: VTableBuilder.h:34
clang::CodeGen::CodeGenVTables::EmitThunks
void EmitThunks(GlobalDecl GD)
EmitThunks - Emit the associated thunks for the given global decl.
Definition: CGVTables.cpp:601
clang::FunctionDecl::param_end
param_iterator param_end()
Definition: Decl.h:2412
clang::CodeGen::CodeGenModule::getVTableLinkage
llvm::GlobalVariable::LinkageTypes getVTableLinkage(const CXXRecordDecl *RD)
Return the appropriate linkage for the vtable, VTT, and type information of the given class...
Definition: CGVTables.cpp:832
clang::CodeGen::RequiredArgs::forPrototypePlus
static RequiredArgs forPrototypePlus(const FunctionProtoType *prototype, unsigned additional)
Compute the arguments required by the given formal prototype, given that there may be some additional...
Definition: CGFunctionInfo.h:427
clang::CodeGen::CodeGenModule::EmitVTableTypeMetadata
void EmitVTableTypeMetadata(const CXXRecordDecl *RD, llvm::GlobalVariable *VTable, const VTableLayout &VTLayout)
Emit type metadata for the given vtable using the given layout.
Definition: CGVTables.cpp:1072
clang::NamedDecl::getLinkageAndVisibility
LinkageInfo getLinkageAndVisibility() const
Determines the linkage and visibility of this entity.
Definition: Decl.cpp:1098
clang::CodeGen::ConstantInitBuilderTemplateBase::beginStruct
StructBuilder beginStruct(llvm::StructType *structTy=nullptr)
Definition: ConstantInitBuilder.h:499
clang::TSK_ExplicitSpecialization
This template specialization was declared or defined by an explicit specialization (C++ [temp...
Definition: Specifiers.h:185
clang::CodeGen::CodeGenTypeCache::Int8PtrTy
llvm::PointerType * Int8PtrTy
Definition: CodeGenTypeCache.h:54
shouldEmitVTableAtEndOfTranslationUnit
static bool shouldEmitVTableAtEndOfTranslationUnit(CodeGenModule &CGM, const CXXRecordDecl *RD)
Given that we&#39;re currently at the end of the translation unit, and we&#39;ve emitted a reference to the v...
Definition: CGVTables.cpp:983
clang::CodeGen::CodeGenVTables::GenerateClassData
void GenerateClassData(const CXXRecordDecl *RD)
GenerateClassData - Generate all the class data required to be generated upon definition of a KeyFunc...
Definition: CGVTables.cpp:929
clang::ThunkInfo::Return
ReturnAdjustment Return
The return adjustment.
Definition: ABI.h:183
clang::CodeGen::CodeGenModule::GetAddrOfFunction
llvm::Constant * GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty=nullptr, bool ForVTable=false, bool DontDefer=false, ForDefinition_t IsForDefinition=NotForDefinition)
Return the address of the given function.
Definition: CodeGenModule.cpp:3298
clang::InternalLinkage
Internal linkage, which indicates that the entity can be referred to from within the translation unit...
Definition: Linkage.h:31
clang::CodeGen::CodeGenFunction::EmitBlock
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false)
EmitBlock - Emit the given block.
Definition: CGStmt.cpp:473
clang::FunctionDecl::isInlined
bool isInlined() const
Determine whether this function should be inlined, because it is either marked "inline" or "constexpr...
Definition: Decl.h:2513
clang::CodeGen::CodeGenTypes::GetFunctionTypeForVTable
llvm::Type * GetFunctionTypeForVTable(GlobalDecl GD)
GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable, given a CXXMethodDecl...
Definition: CGCall.cpp:1684
clang::CodeGen::CodeGenModule::GetVCallVisibilityLevel
llvm::GlobalObject::VCallVisibility GetVCallVisibilityLevel(const CXXRecordDecl *RD)
Returns the vcall visibility of the given type.
Definition: CGVTables.cpp:1049
clang::CodeGen::CodeGenTypeCache::PtrDiffTy
llvm::IntegerType * PtrDiffTy
Definition: CodeGenTypeCache.h:48
clang::ASTContext::toCharUnitsFromBits
CharUnits toCharUnitsFromBits(int64_t BitSize) const
Convert a size in bits to a size in characters.
Definition: ASTContext.cpp:2372
PerformReturnAdjustment
static RValue PerformReturnAdjustment(CodeGenFunction &CGF, QualType ResultType, RValue RV, const ThunkInfo &Thunk)
Definition: CGVTables.cpp:69
clang::ASTContext::getCurrentKeyFunction
const CXXMethodDecl * getCurrentKeyFunction(const CXXRecordDecl *RD)
Get our current best idea for the key function of the given record decl, or nullptr if there isn&#39;t on...
Definition: RecordLayoutBuilder.cpp:3112
clang::CXXRecordDecl
Represents a C++ struct/union/class.
Definition: DeclCXX.h:253
clang::Type::isVoidType
bool isVoidType() const
Definition: Type.h:6777
RecordLayout.h
clang::MangleContext::mangleThunk
virtual void mangleThunk(const CXXMethodDecl *MD, const ThunkInfo &Thunk, raw_ostream &)=0
clang::CodeGen::ConstantStructBuilder
A helper class of ConstantInitBuilder, used for building constant struct initializers.
Definition: ConstantInitBuilder.h:542
clang::VTableLayout
Definition: VTableBuilder.h:232
clang::VTableLayout::getVTableSize
size_t getVTableSize(size_t i) const
Definition: VTableBuilder.h:294
min
__DEVICE__ int min(int __a, int __b)
Definition: __clang_cuda_device_functions.h:1639
clang::TargetCXXABI::isMicrosoft
bool isMicrosoft() const
Is this ABI an MSVC-compatible ABI?
Definition: TargetCXXABI.h:160
clang::VTableComponent::CK_DeletingDtorPointer
A pointer to the deleting destructor.
Definition: VTableBuilder.h:42
clang::CodeGen::CodeGenModule::getCXXABI
CGCXXABI & getCXXABI() const
Definition: CodeGenModule.h:691
clang::CodeGen::CodeGenModule::CreateOrReplaceCXXRuntimeVariable
llvm::GlobalVariable * CreateOrReplaceCXXRuntimeVariable(StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage, unsigned Alignment)
Will return a global variable of the given type.
Definition: CodeGenModule.cpp:3643
getKind
static Decl::Kind getKind(const Decl *D)
Definition: DeclBase.cpp:947
clang::CodeGen::RValue::get
static RValue get(llvm::Value *V)
Definition: CGValue.h:86
clang::CodeGen::CGCXXABI::performReturnAdjustment
virtual llvm::Value * performReturnAdjustment(CodeGenFunction &CGF, Address Ret, const ReturnAdjustment &RA)=0
ConstantInitBuilder.h
clang::CodeGen::ApplyDebugLocation::CreateEmpty
static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF)
Set the IRBuilder to not attach debug locations.
Definition: CGDebugInfo.h:786
clang::ValueDecl::getType
QualType getType() const
Definition: Decl.h:630
clang::CodeGen::CodeGenModule::getVTables
CodeGenVTables & getVTables()
Definition: CodeGenModule.h:700
clang::CodeGen::CodeGenFunction::CGM
CodeGenModule & CGM
Definition: CodeGenFunction.h:258
clang::CodeGen::CodeGenFunction::EmitMustTailThunk
void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr, llvm::FunctionCallee Callee)
Emit a musttail call for a thunk with a potentially adjusted this pointer.
Definition: CGVTables.cpp:390
clang::CodeGen::CallArgList
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:261
clang::CodeGen::CodeGenTypes::arrangeCXXMethodCall
const CGFunctionInfo & arrangeCXXMethodCall(const CallArgList &args, const FunctionProtoType *type, RequiredArgs required, unsigned numPrefixArgs)
Arrange a call to a C++ method, passing the given arguments.
Definition: CGCall.cpp:675
clang::ASTContext::getLangOpts
const LangOptions & getLangOpts() const
Definition: ASTContext.h:724
clang::CXXRecordDecl::vbases
base_class_range vbases()
Definition: DeclCXX.h:604
clang::VTableComponent::CK_CompleteDtorPointer
A pointer to the complete destructor.
Definition: VTableBuilder.h:39
clang::CodeGen::ConstantArrayBuilder
A helper class of ConstantInitBuilder, used for building constant array initializers.
Definition: ConstantInitBuilder.h:525
clang::VTableLayout::getVTableOffset
size_t getVTableOffset(size_t i) const
Definition: VTableBuilder.h:286
clang::VTableComponent::CK_UnusedFunctionPointer
An entry that is never used.
Definition: VTableBuilder.h:49
clang::CodeGen::CGCXXABI::setThunkLinkage
virtual void setThunkLinkage(llvm::Function *Thunk, bool ForVTable, GlobalDecl GD, bool ReturnAdjustment)=0
clang::Decl::getLocation
SourceLocation getLocation() const
Definition: DeclBase.h:429
clang::NamedDecl::isExternallyVisible
bool isExternallyVisible() const
Definition: Decl.h:362
clang::CodeGen::CodeGenModule::EmitVTable
void EmitVTable(CXXRecordDecl *Class)
This is a callback from Sema to tell us that a particular vtable is required to be emitted in this tr...
Definition: CGVTables.cpp:924
clang::Create
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr *> VL, ArrayRef< Expr *> PL, ArrayRef< Expr *> IL, Expr *Step, Expr *CalcStep, Stmt *PreInit, Expr *PostUpdate)
Creates clause with a list of variables VL and a linear step Step.
clang::CodeGen::CodeGenTypes::GetFunctionType
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1556
clang::CodeGen::CodeGenModule::getTriple
const llvm::Triple & getTriple() const
Definition: CodeGenModule.h:687