1 //===--- CGStmtOpenMP.cpp - Emit LLVM Code from Statements ----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This contains code to emit OpenMP nodes as LLVM code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CGOpenMPRuntime.h"
15 #include "CodeGenFunction.h"
16 #include "CodeGenModule.h"
17 #include "TargetInfo.h"
18 #include "clang/AST/Stmt.h"
19 #include "clang/AST/StmtOpenMP.h"
20 using namespace clang;
21 using namespace CodeGen;
22 
GenerateOpenMPCapturedVars(const CapturedStmt & S,SmallVectorImpl<llvm::Value * > & CapturedVars)23 void CodeGenFunction::GenerateOpenMPCapturedVars(
24     const CapturedStmt &S, SmallVectorImpl<llvm::Value *> &CapturedVars) {
25   const RecordDecl *RD = S.getCapturedRecordDecl();
26   auto CurField = RD->field_begin();
27   auto CurCap = S.captures().begin();
28   for (CapturedStmt::const_capture_init_iterator I = S.capture_init_begin(),
29                                                  E = S.capture_init_end();
30        I != E; ++I, ++CurField, ++CurCap) {
31     if (CurField->hasCapturedVLAType()) {
32       auto VAT = CurField->getCapturedVLAType();
33       auto *Val = VLASizeMap[VAT->getSizeExpr()];
34       CapturedVars.push_back(Val);
35     } else if (CurCap->capturesThis())
36       CapturedVars.push_back(CXXThisValue);
37     else if (CurCap->capturesVariableByCopy())
38       CapturedVars.push_back(
39           EmitLoadOfLValue(EmitLValue(*I), SourceLocation()).getScalarVal());
40     else {
41       assert(CurCap->capturesVariable() && "Expected capture by reference.");
42       CapturedVars.push_back(EmitLValue(*I).getAddress().getPointer());
43     }
44   }
45 }
46 
castValueFromUintptr(CodeGenFunction & CGF,QualType DstType,StringRef Name,LValue AddrLV,bool isReferenceType=false)47 static Address castValueFromUintptr(CodeGenFunction &CGF, QualType DstType,
48                                     StringRef Name, LValue AddrLV,
49                                     bool isReferenceType = false) {
50   ASTContext &Ctx = CGF.getContext();
51 
52   auto *CastedPtr = CGF.EmitScalarConversion(
53       AddrLV.getAddress().getPointer(), Ctx.getUIntPtrType(),
54       Ctx.getPointerType(DstType), SourceLocation());
55   auto TmpAddr =
56       CGF.MakeNaturalAlignAddrLValue(CastedPtr, Ctx.getPointerType(DstType))
57           .getAddress();
58 
59   // If we are dealing with references we need to return the address of the
60   // reference instead of the reference of the value.
61   if (isReferenceType) {
62     QualType RefType = Ctx.getLValueReferenceType(DstType);
63     auto *RefVal = TmpAddr.getPointer();
64     TmpAddr = CGF.CreateMemTemp(RefType, Twine(Name) + ".ref");
65     auto TmpLVal = CGF.MakeAddrLValue(TmpAddr, RefType);
66     CGF.EmitScalarInit(RefVal, TmpLVal);
67   }
68 
69   return TmpAddr;
70 }
71 
72 llvm::Function *
GenerateOpenMPCapturedStmtFunction(const CapturedStmt & S)73 CodeGenFunction::GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S) {
74   assert(
75       CapturedStmtInfo &&
76       "CapturedStmtInfo should be set when generating the captured function");
77   const CapturedDecl *CD = S.getCapturedDecl();
78   const RecordDecl *RD = S.getCapturedRecordDecl();
79   assert(CD->hasBody() && "missing CapturedDecl body");
80 
81   // Build the argument list.
82   ASTContext &Ctx = CGM.getContext();
83   FunctionArgList Args;
84   Args.append(CD->param_begin(),
85               std::next(CD->param_begin(), CD->getContextParamPosition()));
86   auto I = S.captures().begin();
87   for (auto *FD : RD->fields()) {
88     QualType ArgType = FD->getType();
89     IdentifierInfo *II = nullptr;
90     VarDecl *CapVar = nullptr;
91 
92     // If this is a capture by copy and the type is not a pointer, the outlined
93     // function argument type should be uintptr and the value properly casted to
94     // uintptr. This is necessary given that the runtime library is only able to
95     // deal with pointers. We can pass in the same way the VLA type sizes to the
96     // outlined function.
97     if ((I->capturesVariableByCopy() && !ArgType->isAnyPointerType()) ||
98         I->capturesVariableArrayType())
99       ArgType = Ctx.getUIntPtrType();
100 
101     if (I->capturesVariable() || I->capturesVariableByCopy()) {
102       CapVar = I->getCapturedVar();
103       II = CapVar->getIdentifier();
104     } else if (I->capturesThis())
105       II = &getContext().Idents.get("this");
106     else {
107       assert(I->capturesVariableArrayType());
108       II = &getContext().Idents.get("vla");
109     }
110     if (ArgType->isVariablyModifiedType())
111       ArgType = getContext().getVariableArrayDecayedType(ArgType);
112     Args.push_back(ImplicitParamDecl::Create(getContext(), nullptr,
113                                              FD->getLocation(), II, ArgType));
114     ++I;
115   }
116   Args.append(
117       std::next(CD->param_begin(), CD->getContextParamPosition() + 1),
118       CD->param_end());
119 
120   // Create the function declaration.
121   FunctionType::ExtInfo ExtInfo;
122   const CGFunctionInfo &FuncInfo =
123       CGM.getTypes().arrangeFreeFunctionDeclaration(Ctx.VoidTy, Args, ExtInfo,
124                                                     /*IsVariadic=*/false);
125   llvm::FunctionType *FuncLLVMTy = CGM.getTypes().GetFunctionType(FuncInfo);
126 
127   llvm::Function *F = llvm::Function::Create(
128       FuncLLVMTy, llvm::GlobalValue::InternalLinkage,
129       CapturedStmtInfo->getHelperName(), &CGM.getModule());
130   CGM.SetInternalFunctionAttributes(CD, F, FuncInfo);
131   if (CD->isNothrow())
132     F->addFnAttr(llvm::Attribute::NoUnwind);
133 
134   // Generate the function.
135   StartFunction(CD, Ctx.VoidTy, F, FuncInfo, Args, CD->getLocation(),
136                 CD->getBody()->getLocStart());
137   unsigned Cnt = CD->getContextParamPosition();
138   I = S.captures().begin();
139   for (auto *FD : RD->fields()) {
140     // If we are capturing a pointer by copy we don't need to do anything, just
141     // use the value that we get from the arguments.
142     if (I->capturesVariableByCopy() && FD->getType()->isAnyPointerType()) {
143       setAddrOfLocalVar(I->getCapturedVar(), GetAddrOfLocalVar(Args[Cnt]));
144       ++Cnt, ++I;
145       continue;
146     }
147 
148     LValue ArgLVal =
149         MakeAddrLValue(GetAddrOfLocalVar(Args[Cnt]), Args[Cnt]->getType(),
150                        AlignmentSource::Decl);
151     if (FD->hasCapturedVLAType()) {
152       LValue CastedArgLVal =
153           MakeAddrLValue(castValueFromUintptr(*this, FD->getType(),
154                                               Args[Cnt]->getName(), ArgLVal),
155                          FD->getType(), AlignmentSource::Decl);
156       auto *ExprArg =
157           EmitLoadOfLValue(CastedArgLVal, SourceLocation()).getScalarVal();
158       auto VAT = FD->getCapturedVLAType();
159       VLASizeMap[VAT->getSizeExpr()] = ExprArg;
160     } else if (I->capturesVariable()) {
161       auto *Var = I->getCapturedVar();
162       QualType VarTy = Var->getType();
163       Address ArgAddr = ArgLVal.getAddress();
164       if (!VarTy->isReferenceType()) {
165         ArgAddr = EmitLoadOfReference(
166             ArgAddr, ArgLVal.getType()->castAs<ReferenceType>());
167       }
168       setAddrOfLocalVar(
169           Var, Address(ArgAddr.getPointer(), getContext().getDeclAlign(Var)));
170     } else if (I->capturesVariableByCopy()) {
171       assert(!FD->getType()->isAnyPointerType() &&
172              "Not expecting a captured pointer.");
173       auto *Var = I->getCapturedVar();
174       QualType VarTy = Var->getType();
175       setAddrOfLocalVar(I->getCapturedVar(),
176                         castValueFromUintptr(*this, FD->getType(),
177                                              Args[Cnt]->getName(), ArgLVal,
178                                              VarTy->isReferenceType()));
179     } else {
180       // If 'this' is captured, load it into CXXThisValue.
181       assert(I->capturesThis());
182       CXXThisValue =
183           EmitLoadOfLValue(ArgLVal, Args[Cnt]->getLocation()).getScalarVal();
184     }
185     ++Cnt, ++I;
186   }
187 
188   PGO.assignRegionCounters(GlobalDecl(CD), F);
189   CapturedStmtInfo->EmitBody(*this, CD->getBody());
190   FinishFunction(CD->getBodyRBrace());
191 
192   return F;
193 }
194 
195 //===----------------------------------------------------------------------===//
196 //                              OpenMP Directive Emission
197 //===----------------------------------------------------------------------===//
EmitOMPAggregateAssign(Address DestAddr,Address SrcAddr,QualType OriginalType,const llvm::function_ref<void (Address,Address)> & CopyGen)198 void CodeGenFunction::EmitOMPAggregateAssign(
199     Address DestAddr, Address SrcAddr, QualType OriginalType,
200     const llvm::function_ref<void(Address, Address)> &CopyGen) {
201   // Perform element-by-element initialization.
202   QualType ElementTy;
203 
204   // Drill down to the base element type on both arrays.
205   auto ArrayTy = OriginalType->getAsArrayTypeUnsafe();
206   auto NumElements = emitArrayLength(ArrayTy, ElementTy, DestAddr);
207   SrcAddr = Builder.CreateElementBitCast(SrcAddr, DestAddr.getElementType());
208 
209   auto SrcBegin = SrcAddr.getPointer();
210   auto DestBegin = DestAddr.getPointer();
211   // Cast from pointer to array type to pointer to single element.
212   auto DestEnd = Builder.CreateGEP(DestBegin, NumElements);
213   // The basic structure here is a while-do loop.
214   auto BodyBB = createBasicBlock("omp.arraycpy.body");
215   auto DoneBB = createBasicBlock("omp.arraycpy.done");
216   auto IsEmpty =
217       Builder.CreateICmpEQ(DestBegin, DestEnd, "omp.arraycpy.isempty");
218   Builder.CreateCondBr(IsEmpty, DoneBB, BodyBB);
219 
220   // Enter the loop body, making that address the current address.
221   auto EntryBB = Builder.GetInsertBlock();
222   EmitBlock(BodyBB);
223 
224   CharUnits ElementSize = getContext().getTypeSizeInChars(ElementTy);
225 
226   llvm::PHINode *SrcElementPHI =
227     Builder.CreatePHI(SrcBegin->getType(), 2, "omp.arraycpy.srcElementPast");
228   SrcElementPHI->addIncoming(SrcBegin, EntryBB);
229   Address SrcElementCurrent =
230       Address(SrcElementPHI,
231               SrcAddr.getAlignment().alignmentOfArrayElement(ElementSize));
232 
233   llvm::PHINode *DestElementPHI =
234     Builder.CreatePHI(DestBegin->getType(), 2, "omp.arraycpy.destElementPast");
235   DestElementPHI->addIncoming(DestBegin, EntryBB);
236   Address DestElementCurrent =
237     Address(DestElementPHI,
238             DestAddr.getAlignment().alignmentOfArrayElement(ElementSize));
239 
240   // Emit copy.
241   CopyGen(DestElementCurrent, SrcElementCurrent);
242 
243   // Shift the address forward by one element.
244   auto DestElementNext = Builder.CreateConstGEP1_32(
245       DestElementPHI, /*Idx0=*/1, "omp.arraycpy.dest.element");
246   auto SrcElementNext = Builder.CreateConstGEP1_32(
247       SrcElementPHI, /*Idx0=*/1, "omp.arraycpy.src.element");
248   // Check whether we've reached the end.
249   auto Done =
250       Builder.CreateICmpEQ(DestElementNext, DestEnd, "omp.arraycpy.done");
251   Builder.CreateCondBr(Done, DoneBB, BodyBB);
252   DestElementPHI->addIncoming(DestElementNext, Builder.GetInsertBlock());
253   SrcElementPHI->addIncoming(SrcElementNext, Builder.GetInsertBlock());
254 
255   // Done.
256   EmitBlock(DoneBB, /*IsFinished=*/true);
257 }
258 
259 /// \brief Emit initialization of arrays of complex types.
260 /// \param DestAddr Address of the array.
261 /// \param Type Type of array.
262 /// \param Init Initial expression of array.
EmitOMPAggregateInit(CodeGenFunction & CGF,Address DestAddr,QualType Type,const Expr * Init)263 static void EmitOMPAggregateInit(CodeGenFunction &CGF, Address DestAddr,
264                                  QualType Type, const Expr *Init) {
265   // Perform element-by-element initialization.
266   QualType ElementTy;
267 
268   // Drill down to the base element type on both arrays.
269   auto ArrayTy = Type->getAsArrayTypeUnsafe();
270   auto NumElements = CGF.emitArrayLength(ArrayTy, ElementTy, DestAddr);
271   DestAddr =
272       CGF.Builder.CreateElementBitCast(DestAddr, DestAddr.getElementType());
273 
274   auto DestBegin = DestAddr.getPointer();
275   // Cast from pointer to array type to pointer to single element.
276   auto DestEnd = CGF.Builder.CreateGEP(DestBegin, NumElements);
277   // The basic structure here is a while-do loop.
278   auto BodyBB = CGF.createBasicBlock("omp.arrayinit.body");
279   auto DoneBB = CGF.createBasicBlock("omp.arrayinit.done");
280   auto IsEmpty =
281       CGF.Builder.CreateICmpEQ(DestBegin, DestEnd, "omp.arrayinit.isempty");
282   CGF.Builder.CreateCondBr(IsEmpty, DoneBB, BodyBB);
283 
284   // Enter the loop body, making that address the current address.
285   auto EntryBB = CGF.Builder.GetInsertBlock();
286   CGF.EmitBlock(BodyBB);
287 
288   CharUnits ElementSize = CGF.getContext().getTypeSizeInChars(ElementTy);
289 
290   llvm::PHINode *DestElementPHI = CGF.Builder.CreatePHI(
291       DestBegin->getType(), 2, "omp.arraycpy.destElementPast");
292   DestElementPHI->addIncoming(DestBegin, EntryBB);
293   Address DestElementCurrent =
294       Address(DestElementPHI,
295               DestAddr.getAlignment().alignmentOfArrayElement(ElementSize));
296 
297   // Emit copy.
298   {
299     CodeGenFunction::RunCleanupsScope InitScope(CGF);
300     CGF.EmitAnyExprToMem(Init, DestElementCurrent, ElementTy.getQualifiers(),
301                          /*IsInitializer=*/false);
302   }
303 
304   // Shift the address forward by one element.
305   auto DestElementNext = CGF.Builder.CreateConstGEP1_32(
306       DestElementPHI, /*Idx0=*/1, "omp.arraycpy.dest.element");
307   // Check whether we've reached the end.
308   auto Done =
309       CGF.Builder.CreateICmpEQ(DestElementNext, DestEnd, "omp.arraycpy.done");
310   CGF.Builder.CreateCondBr(Done, DoneBB, BodyBB);
311   DestElementPHI->addIncoming(DestElementNext, CGF.Builder.GetInsertBlock());
312 
313   // Done.
314   CGF.EmitBlock(DoneBB, /*IsFinished=*/true);
315 }
316 
EmitOMPCopy(QualType OriginalType,Address DestAddr,Address SrcAddr,const VarDecl * DestVD,const VarDecl * SrcVD,const Expr * Copy)317 void CodeGenFunction::EmitOMPCopy(QualType OriginalType, Address DestAddr,
318                                   Address SrcAddr, const VarDecl *DestVD,
319                                   const VarDecl *SrcVD, const Expr *Copy) {
320   if (OriginalType->isArrayType()) {
321     auto *BO = dyn_cast<BinaryOperator>(Copy);
322     if (BO && BO->getOpcode() == BO_Assign) {
323       // Perform simple memcpy for simple copying.
324       EmitAggregateAssign(DestAddr, SrcAddr, OriginalType);
325     } else {
326       // For arrays with complex element types perform element by element
327       // copying.
328       EmitOMPAggregateAssign(
329           DestAddr, SrcAddr, OriginalType,
330           [this, Copy, SrcVD, DestVD](Address DestElement, Address SrcElement) {
331             // Working with the single array element, so have to remap
332             // destination and source variables to corresponding array
333             // elements.
334             CodeGenFunction::OMPPrivateScope Remap(*this);
335             Remap.addPrivate(DestVD, [DestElement]() -> Address {
336               return DestElement;
337             });
338             Remap.addPrivate(
339                 SrcVD, [SrcElement]() -> Address { return SrcElement; });
340             (void)Remap.Privatize();
341             EmitIgnoredExpr(Copy);
342           });
343     }
344   } else {
345     // Remap pseudo source variable to private copy.
346     CodeGenFunction::OMPPrivateScope Remap(*this);
347     Remap.addPrivate(SrcVD, [SrcAddr]() -> Address { return SrcAddr; });
348     Remap.addPrivate(DestVD, [DestAddr]() -> Address { return DestAddr; });
349     (void)Remap.Privatize();
350     // Emit copying of the whole variable.
351     EmitIgnoredExpr(Copy);
352   }
353 }
354 
EmitOMPFirstprivateClause(const OMPExecutableDirective & D,OMPPrivateScope & PrivateScope)355 bool CodeGenFunction::EmitOMPFirstprivateClause(const OMPExecutableDirective &D,
356                                                 OMPPrivateScope &PrivateScope) {
357   if (!HaveInsertPoint())
358     return false;
359   llvm::DenseSet<const VarDecl *> EmittedAsFirstprivate;
360   for (const auto *C : D.getClausesOfKind<OMPFirstprivateClause>()) {
361     auto IRef = C->varlist_begin();
362     auto InitsRef = C->inits().begin();
363     for (auto IInit : C->private_copies()) {
364       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
365       if (EmittedAsFirstprivate.count(OrigVD) == 0) {
366         EmittedAsFirstprivate.insert(OrigVD);
367         auto *VD = cast<VarDecl>(cast<DeclRefExpr>(IInit)->getDecl());
368         auto *VDInit = cast<VarDecl>(cast<DeclRefExpr>(*InitsRef)->getDecl());
369         bool IsRegistered;
370         DeclRefExpr DRE(
371             const_cast<VarDecl *>(OrigVD),
372             /*RefersToEnclosingVariableOrCapture=*/CapturedStmtInfo->lookup(
373                 OrigVD) != nullptr,
374             (*IRef)->getType(), VK_LValue, (*IRef)->getExprLoc());
375         Address OriginalAddr = EmitLValue(&DRE).getAddress();
376         QualType Type = OrigVD->getType();
377         if (Type->isArrayType()) {
378           // Emit VarDecl with copy init for arrays.
379           // Get the address of the original variable captured in current
380           // captured region.
381           IsRegistered = PrivateScope.addPrivate(OrigVD, [&]() -> Address {
382             auto Emission = EmitAutoVarAlloca(*VD);
383             auto *Init = VD->getInit();
384             if (!isa<CXXConstructExpr>(Init) || isTrivialInitializer(Init)) {
385               // Perform simple memcpy.
386               EmitAggregateAssign(Emission.getAllocatedAddress(), OriginalAddr,
387                                   Type);
388             } else {
389               EmitOMPAggregateAssign(
390                   Emission.getAllocatedAddress(), OriginalAddr, Type,
391                   [this, VDInit, Init](Address DestElement,
392                                        Address SrcElement) {
393                     // Clean up any temporaries needed by the initialization.
394                     RunCleanupsScope InitScope(*this);
395                     // Emit initialization for single element.
396                     setAddrOfLocalVar(VDInit, SrcElement);
397                     EmitAnyExprToMem(Init, DestElement,
398                                      Init->getType().getQualifiers(),
399                                      /*IsInitializer*/ false);
400                     LocalDeclMap.erase(VDInit);
401                   });
402             }
403             EmitAutoVarCleanups(Emission);
404             return Emission.getAllocatedAddress();
405           });
406         } else {
407           IsRegistered = PrivateScope.addPrivate(OrigVD, [&]() -> Address {
408             // Emit private VarDecl with copy init.
409             // Remap temp VDInit variable to the address of the original
410             // variable
411             // (for proper handling of captured global variables).
412             setAddrOfLocalVar(VDInit, OriginalAddr);
413             EmitDecl(*VD);
414             LocalDeclMap.erase(VDInit);
415             return GetAddrOfLocalVar(VD);
416           });
417         }
418         assert(IsRegistered &&
419                "firstprivate var already registered as private");
420         // Silence the warning about unused variable.
421         (void)IsRegistered;
422       }
423       ++IRef, ++InitsRef;
424     }
425   }
426   return !EmittedAsFirstprivate.empty();
427 }
428 
EmitOMPPrivateClause(const OMPExecutableDirective & D,CodeGenFunction::OMPPrivateScope & PrivateScope)429 void CodeGenFunction::EmitOMPPrivateClause(
430     const OMPExecutableDirective &D,
431     CodeGenFunction::OMPPrivateScope &PrivateScope) {
432   if (!HaveInsertPoint())
433     return;
434   llvm::DenseSet<const VarDecl *> EmittedAsPrivate;
435   for (const auto *C : D.getClausesOfKind<OMPPrivateClause>()) {
436     auto IRef = C->varlist_begin();
437     for (auto IInit : C->private_copies()) {
438       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
439       if (EmittedAsPrivate.insert(OrigVD->getCanonicalDecl()).second) {
440         auto VD = cast<VarDecl>(cast<DeclRefExpr>(IInit)->getDecl());
441         bool IsRegistered =
442             PrivateScope.addPrivate(OrigVD, [&]() -> Address {
443               // Emit private VarDecl with copy init.
444               EmitDecl(*VD);
445               return GetAddrOfLocalVar(VD);
446             });
447         assert(IsRegistered && "private var already registered as private");
448         // Silence the warning about unused variable.
449         (void)IsRegistered;
450       }
451       ++IRef;
452     }
453   }
454 }
455 
EmitOMPCopyinClause(const OMPExecutableDirective & D)456 bool CodeGenFunction::EmitOMPCopyinClause(const OMPExecutableDirective &D) {
457   if (!HaveInsertPoint())
458     return false;
459   // threadprivate_var1 = master_threadprivate_var1;
460   // operator=(threadprivate_var2, master_threadprivate_var2);
461   // ...
462   // __kmpc_barrier(&loc, global_tid);
463   llvm::DenseSet<const VarDecl *> CopiedVars;
464   llvm::BasicBlock *CopyBegin = nullptr, *CopyEnd = nullptr;
465   for (const auto *C : D.getClausesOfKind<OMPCopyinClause>()) {
466     auto IRef = C->varlist_begin();
467     auto ISrcRef = C->source_exprs().begin();
468     auto IDestRef = C->destination_exprs().begin();
469     for (auto *AssignOp : C->assignment_ops()) {
470       auto *VD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
471       QualType Type = VD->getType();
472       if (CopiedVars.insert(VD->getCanonicalDecl()).second) {
473 
474         // Get the address of the master variable. If we are emitting code with
475         // TLS support, the address is passed from the master as field in the
476         // captured declaration.
477         Address MasterAddr = Address::invalid();
478         if (getLangOpts().OpenMPUseTLS &&
479             getContext().getTargetInfo().isTLSSupported()) {
480           assert(CapturedStmtInfo->lookup(VD) &&
481                  "Copyin threadprivates should have been captured!");
482           DeclRefExpr DRE(const_cast<VarDecl *>(VD), true, (*IRef)->getType(),
483                           VK_LValue, (*IRef)->getExprLoc());
484           MasterAddr = EmitLValue(&DRE).getAddress();
485           LocalDeclMap.erase(VD);
486         } else {
487           MasterAddr =
488             Address(VD->isStaticLocal() ? CGM.getStaticLocalDeclAddress(VD)
489                                         : CGM.GetAddrOfGlobal(VD),
490                     getContext().getDeclAlign(VD));
491         }
492         // Get the address of the threadprivate variable.
493         Address PrivateAddr = EmitLValue(*IRef).getAddress();
494         if (CopiedVars.size() == 1) {
495           // At first check if current thread is a master thread. If it is, no
496           // need to copy data.
497           CopyBegin = createBasicBlock("copyin.not.master");
498           CopyEnd = createBasicBlock("copyin.not.master.end");
499           Builder.CreateCondBr(
500               Builder.CreateICmpNE(
501                   Builder.CreatePtrToInt(MasterAddr.getPointer(), CGM.IntPtrTy),
502                   Builder.CreatePtrToInt(PrivateAddr.getPointer(), CGM.IntPtrTy)),
503               CopyBegin, CopyEnd);
504           EmitBlock(CopyBegin);
505         }
506         auto *SrcVD = cast<VarDecl>(cast<DeclRefExpr>(*ISrcRef)->getDecl());
507         auto *DestVD = cast<VarDecl>(cast<DeclRefExpr>(*IDestRef)->getDecl());
508         EmitOMPCopy(Type, PrivateAddr, MasterAddr, DestVD, SrcVD, AssignOp);
509       }
510       ++IRef;
511       ++ISrcRef;
512       ++IDestRef;
513     }
514   }
515   if (CopyEnd) {
516     // Exit out of copying procedure for non-master thread.
517     EmitBlock(CopyEnd, /*IsFinished=*/true);
518     return true;
519   }
520   return false;
521 }
522 
EmitOMPLastprivateClauseInit(const OMPExecutableDirective & D,OMPPrivateScope & PrivateScope)523 bool CodeGenFunction::EmitOMPLastprivateClauseInit(
524     const OMPExecutableDirective &D, OMPPrivateScope &PrivateScope) {
525   if (!HaveInsertPoint())
526     return false;
527   bool HasAtLeastOneLastprivate = false;
528   llvm::DenseSet<const VarDecl *> AlreadyEmittedVars;
529   for (const auto *C : D.getClausesOfKind<OMPLastprivateClause>()) {
530     HasAtLeastOneLastprivate = true;
531     auto IRef = C->varlist_begin();
532     auto IDestRef = C->destination_exprs().begin();
533     for (auto *IInit : C->private_copies()) {
534       // Keep the address of the original variable for future update at the end
535       // of the loop.
536       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
537       if (AlreadyEmittedVars.insert(OrigVD->getCanonicalDecl()).second) {
538         auto *DestVD = cast<VarDecl>(cast<DeclRefExpr>(*IDestRef)->getDecl());
539         PrivateScope.addPrivate(DestVD, [this, OrigVD, IRef]() -> Address {
540           DeclRefExpr DRE(
541               const_cast<VarDecl *>(OrigVD),
542               /*RefersToEnclosingVariableOrCapture=*/CapturedStmtInfo->lookup(
543                   OrigVD) != nullptr,
544               (*IRef)->getType(), VK_LValue, (*IRef)->getExprLoc());
545           return EmitLValue(&DRE).getAddress();
546         });
547         // Check if the variable is also a firstprivate: in this case IInit is
548         // not generated. Initialization of this variable will happen in codegen
549         // for 'firstprivate' clause.
550         if (IInit) {
551           auto *VD = cast<VarDecl>(cast<DeclRefExpr>(IInit)->getDecl());
552           bool IsRegistered =
553               PrivateScope.addPrivate(OrigVD, [&]() -> Address {
554                 // Emit private VarDecl with copy init.
555                 EmitDecl(*VD);
556                 return GetAddrOfLocalVar(VD);
557               });
558           assert(IsRegistered &&
559                  "lastprivate var already registered as private");
560           (void)IsRegistered;
561         }
562       }
563       ++IRef, ++IDestRef;
564     }
565   }
566   return HasAtLeastOneLastprivate;
567 }
568 
EmitOMPLastprivateClauseFinal(const OMPExecutableDirective & D,llvm::Value * IsLastIterCond)569 void CodeGenFunction::EmitOMPLastprivateClauseFinal(
570     const OMPExecutableDirective &D, llvm::Value *IsLastIterCond) {
571   if (!HaveInsertPoint())
572     return;
573   // Emit following code:
574   // if (<IsLastIterCond>) {
575   //   orig_var1 = private_orig_var1;
576   //   ...
577   //   orig_varn = private_orig_varn;
578   // }
579   llvm::BasicBlock *ThenBB = nullptr;
580   llvm::BasicBlock *DoneBB = nullptr;
581   if (IsLastIterCond) {
582     ThenBB = createBasicBlock(".omp.lastprivate.then");
583     DoneBB = createBasicBlock(".omp.lastprivate.done");
584     Builder.CreateCondBr(IsLastIterCond, ThenBB, DoneBB);
585     EmitBlock(ThenBB);
586   }
587   llvm::DenseMap<const Decl *, const Expr *> LoopCountersAndUpdates;
588   const Expr *LastIterVal = nullptr;
589   const Expr *IVExpr = nullptr;
590   const Expr *IncExpr = nullptr;
591   if (auto *LoopDirective = dyn_cast<OMPLoopDirective>(&D)) {
592     if (isOpenMPWorksharingDirective(D.getDirectiveKind())) {
593       LastIterVal = cast<VarDecl>(cast<DeclRefExpr>(
594                                       LoopDirective->getUpperBoundVariable())
595                                       ->getDecl())
596                         ->getAnyInitializer();
597       IVExpr = LoopDirective->getIterationVariable();
598       IncExpr = LoopDirective->getInc();
599       auto IUpdate = LoopDirective->updates().begin();
600       for (auto *E : LoopDirective->counters()) {
601         auto *D = cast<DeclRefExpr>(E)->getDecl()->getCanonicalDecl();
602         LoopCountersAndUpdates[D] = *IUpdate;
603         ++IUpdate;
604       }
605     }
606   }
607   {
608     llvm::DenseSet<const VarDecl *> AlreadyEmittedVars;
609     bool FirstLCV = true;
610     for (const auto *C : D.getClausesOfKind<OMPLastprivateClause>()) {
611       auto IRef = C->varlist_begin();
612       auto ISrcRef = C->source_exprs().begin();
613       auto IDestRef = C->destination_exprs().begin();
614       for (auto *AssignOp : C->assignment_ops()) {
615         auto *PrivateVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
616         QualType Type = PrivateVD->getType();
617         auto *CanonicalVD = PrivateVD->getCanonicalDecl();
618         if (AlreadyEmittedVars.insert(CanonicalVD).second) {
619           // If lastprivate variable is a loop control variable for loop-based
620           // directive, update its value before copyin back to original
621           // variable.
622           if (auto *UpExpr = LoopCountersAndUpdates.lookup(CanonicalVD)) {
623             if (FirstLCV && LastIterVal) {
624               EmitAnyExprToMem(LastIterVal, EmitLValue(IVExpr).getAddress(),
625                                IVExpr->getType().getQualifiers(),
626                                /*IsInitializer=*/false);
627               EmitIgnoredExpr(IncExpr);
628               FirstLCV = false;
629             }
630             EmitIgnoredExpr(UpExpr);
631           }
632           auto *SrcVD = cast<VarDecl>(cast<DeclRefExpr>(*ISrcRef)->getDecl());
633           auto *DestVD = cast<VarDecl>(cast<DeclRefExpr>(*IDestRef)->getDecl());
634           // Get the address of the original variable.
635           Address OriginalAddr = GetAddrOfLocalVar(DestVD);
636           // Get the address of the private variable.
637           Address PrivateAddr = GetAddrOfLocalVar(PrivateVD);
638           if (auto RefTy = PrivateVD->getType()->getAs<ReferenceType>())
639             PrivateAddr =
640               Address(Builder.CreateLoad(PrivateAddr),
641                       getNaturalTypeAlignment(RefTy->getPointeeType()));
642           EmitOMPCopy(Type, OriginalAddr, PrivateAddr, DestVD, SrcVD, AssignOp);
643         }
644         ++IRef;
645         ++ISrcRef;
646         ++IDestRef;
647       }
648     }
649   }
650   if (IsLastIterCond) {
651     EmitBlock(DoneBB, /*IsFinished=*/true);
652   }
653 }
654 
EmitOMPReductionClauseInit(const OMPExecutableDirective & D,CodeGenFunction::OMPPrivateScope & PrivateScope)655 void CodeGenFunction::EmitOMPReductionClauseInit(
656     const OMPExecutableDirective &D,
657     CodeGenFunction::OMPPrivateScope &PrivateScope) {
658   if (!HaveInsertPoint())
659     return;
660   for (const auto *C : D.getClausesOfKind<OMPReductionClause>()) {
661     auto ILHS = C->lhs_exprs().begin();
662     auto IRHS = C->rhs_exprs().begin();
663     auto IPriv = C->privates().begin();
664     for (auto IRef : C->varlists()) {
665       auto *LHSVD = cast<VarDecl>(cast<DeclRefExpr>(*ILHS)->getDecl());
666       auto *RHSVD = cast<VarDecl>(cast<DeclRefExpr>(*IRHS)->getDecl());
667       auto *PrivateVD = cast<VarDecl>(cast<DeclRefExpr>(*IPriv)->getDecl());
668       if (auto *OASE = dyn_cast<OMPArraySectionExpr>(IRef)) {
669         auto *Base = OASE->getBase()->IgnoreParenImpCasts();
670         while (auto *TempOASE = dyn_cast<OMPArraySectionExpr>(Base))
671           Base = TempOASE->getBase()->IgnoreParenImpCasts();
672         while (auto *TempASE = dyn_cast<ArraySubscriptExpr>(Base))
673           Base = TempASE->getBase()->IgnoreParenImpCasts();
674         auto *DE = cast<DeclRefExpr>(Base);
675         auto *OrigVD = cast<VarDecl>(DE->getDecl());
676         auto OASELValueLB = EmitOMPArraySectionExpr(OASE);
677         auto OASELValueUB =
678             EmitOMPArraySectionExpr(OASE, /*IsLowerBound=*/false);
679         auto OriginalBaseLValue = EmitLValue(DE);
680         auto BaseLValue = OriginalBaseLValue;
681         auto *Zero = Builder.getInt64(/*C=*/0);
682         llvm::SmallVector<llvm::Value *, 4> Indexes;
683         Indexes.push_back(Zero);
684         auto *ItemTy =
685             OASELValueLB.getPointer()->getType()->getPointerElementType();
686         auto *Ty = BaseLValue.getPointer()->getType()->getPointerElementType();
687         while (Ty != ItemTy) {
688           Indexes.push_back(Zero);
689           Ty = Ty->getPointerElementType();
690         }
691         BaseLValue = MakeAddrLValue(
692             Address(Builder.CreateInBoundsGEP(BaseLValue.getPointer(), Indexes),
693                     OASELValueLB.getAlignment()),
694             OASELValueLB.getType(), OASELValueLB.getAlignmentSource());
695         // Store the address of the original variable associated with the LHS
696         // implicit variable.
697         PrivateScope.addPrivate(LHSVD, [this, OASELValueLB]() -> Address {
698           return OASELValueLB.getAddress();
699         });
700         // Emit reduction copy.
701         bool IsRegistered = PrivateScope.addPrivate(
702             OrigVD, [this, PrivateVD, BaseLValue, OASELValueLB, OASELValueUB,
703                      OriginalBaseLValue]() -> Address {
704               // Emit VarDecl with copy init for arrays.
705               // Get the address of the original variable captured in current
706               // captured region.
707               auto *Size = Builder.CreatePtrDiff(OASELValueUB.getPointer(),
708                                                  OASELValueLB.getPointer());
709               Size = Builder.CreateNUWAdd(
710                   Size, llvm::ConstantInt::get(Size->getType(), /*V=*/1));
711               CodeGenFunction::OpaqueValueMapping OpaqueMap(
712                   *this, cast<OpaqueValueExpr>(
713                              getContext()
714                                  .getAsVariableArrayType(PrivateVD->getType())
715                                  ->getSizeExpr()),
716                   RValue::get(Size));
717               EmitVariablyModifiedType(PrivateVD->getType());
718               auto Emission = EmitAutoVarAlloca(*PrivateVD);
719               auto Addr = Emission.getAllocatedAddress();
720               auto *Init = PrivateVD->getInit();
721               EmitOMPAggregateInit(*this, Addr, PrivateVD->getType(), Init);
722               EmitAutoVarCleanups(Emission);
723               // Emit private VarDecl with reduction init.
724               auto *Offset = Builder.CreatePtrDiff(BaseLValue.getPointer(),
725                                                    OASELValueLB.getPointer());
726               auto *Ptr = Builder.CreateGEP(Addr.getPointer(), Offset);
727               Ptr = Builder.CreatePointerBitCastOrAddrSpaceCast(
728                   Ptr, OriginalBaseLValue.getPointer()->getType());
729               return Address(Ptr, OriginalBaseLValue.getAlignment());
730             });
731         assert(IsRegistered && "private var already registered as private");
732         // Silence the warning about unused variable.
733         (void)IsRegistered;
734         PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
735           return GetAddrOfLocalVar(PrivateVD);
736         });
737       } else if (auto *ASE = dyn_cast<ArraySubscriptExpr>(IRef)) {
738         auto *Base = ASE->getBase()->IgnoreParenImpCasts();
739         while (auto *TempASE = dyn_cast<ArraySubscriptExpr>(Base))
740           Base = TempASE->getBase()->IgnoreParenImpCasts();
741         auto *DE = cast<DeclRefExpr>(Base);
742         auto *OrigVD = cast<VarDecl>(DE->getDecl());
743         auto ASELValue = EmitLValue(ASE);
744         auto OriginalBaseLValue = EmitLValue(DE);
745         auto BaseLValue = OriginalBaseLValue;
746         auto *Zero = Builder.getInt64(/*C=*/0);
747         llvm::SmallVector<llvm::Value *, 4> Indexes;
748         Indexes.push_back(Zero);
749         auto *ItemTy =
750             ASELValue.getPointer()->getType()->getPointerElementType();
751         auto *Ty = BaseLValue.getPointer()->getType()->getPointerElementType();
752         while (Ty != ItemTy) {
753           Indexes.push_back(Zero);
754           Ty = Ty->getPointerElementType();
755         }
756         BaseLValue = MakeAddrLValue(
757             Address(Builder.CreateInBoundsGEP(BaseLValue.getPointer(), Indexes),
758                     ASELValue.getAlignment()),
759             ASELValue.getType(), ASELValue.getAlignmentSource());
760         // Store the address of the original variable associated with the LHS
761         // implicit variable.
762         PrivateScope.addPrivate(LHSVD, [this, ASELValue]() -> Address {
763           return ASELValue.getAddress();
764         });
765         // Emit reduction copy.
766         bool IsRegistered = PrivateScope.addPrivate(
767             OrigVD, [this, PrivateVD, BaseLValue, ASELValue,
768                      OriginalBaseLValue]() -> Address {
769               // Emit private VarDecl with reduction init.
770               EmitDecl(*PrivateVD);
771               auto Addr = GetAddrOfLocalVar(PrivateVD);
772               auto *Offset = Builder.CreatePtrDiff(BaseLValue.getPointer(),
773                                                    ASELValue.getPointer());
774               auto *Ptr = Builder.CreateGEP(Addr.getPointer(), Offset);
775               Ptr = Builder.CreatePointerBitCastOrAddrSpaceCast(
776                   Ptr, OriginalBaseLValue.getPointer()->getType());
777               return Address(Ptr, OriginalBaseLValue.getAlignment());
778             });
779         assert(IsRegistered && "private var already registered as private");
780         // Silence the warning about unused variable.
781         (void)IsRegistered;
782         PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
783           return GetAddrOfLocalVar(PrivateVD);
784         });
785       } else {
786         auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(IRef)->getDecl());
787         // Store the address of the original variable associated with the LHS
788         // implicit variable.
789         PrivateScope.addPrivate(LHSVD, [this, OrigVD, IRef]() -> Address {
790           DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
791                           CapturedStmtInfo->lookup(OrigVD) != nullptr,
792                           IRef->getType(), VK_LValue, IRef->getExprLoc());
793           return EmitLValue(&DRE).getAddress();
794         });
795         // Emit reduction copy.
796         bool IsRegistered =
797             PrivateScope.addPrivate(OrigVD, [this, PrivateVD]() -> Address {
798               // Emit private VarDecl with reduction init.
799               EmitDecl(*PrivateVD);
800               return GetAddrOfLocalVar(PrivateVD);
801             });
802         assert(IsRegistered && "private var already registered as private");
803         // Silence the warning about unused variable.
804         (void)IsRegistered;
805         PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
806           return GetAddrOfLocalVar(PrivateVD);
807         });
808       }
809       ++ILHS, ++IRHS, ++IPriv;
810     }
811   }
812 }
813 
EmitOMPReductionClauseFinal(const OMPExecutableDirective & D)814 void CodeGenFunction::EmitOMPReductionClauseFinal(
815     const OMPExecutableDirective &D) {
816   if (!HaveInsertPoint())
817     return;
818   llvm::SmallVector<const Expr *, 8> Privates;
819   llvm::SmallVector<const Expr *, 8> LHSExprs;
820   llvm::SmallVector<const Expr *, 8> RHSExprs;
821   llvm::SmallVector<const Expr *, 8> ReductionOps;
822   bool HasAtLeastOneReduction = false;
823   for (const auto *C : D.getClausesOfKind<OMPReductionClause>()) {
824     HasAtLeastOneReduction = true;
825     Privates.append(C->privates().begin(), C->privates().end());
826     LHSExprs.append(C->lhs_exprs().begin(), C->lhs_exprs().end());
827     RHSExprs.append(C->rhs_exprs().begin(), C->rhs_exprs().end());
828     ReductionOps.append(C->reduction_ops().begin(), C->reduction_ops().end());
829   }
830   if (HasAtLeastOneReduction) {
831     // Emit nowait reduction if nowait clause is present or directive is a
832     // parallel directive (it always has implicit barrier).
833     CGM.getOpenMPRuntime().emitReduction(
834         *this, D.getLocEnd(), Privates, LHSExprs, RHSExprs, ReductionOps,
835         D.getSingleClause<OMPNowaitClause>() ||
836             isOpenMPParallelDirective(D.getDirectiveKind()) ||
837             D.getDirectiveKind() == OMPD_simd,
838         D.getDirectiveKind() == OMPD_simd);
839   }
840 }
841 
emitCommonOMPParallelDirective(CodeGenFunction & CGF,const OMPExecutableDirective & S,OpenMPDirectiveKind InnermostKind,const RegionCodeGenTy & CodeGen)842 static void emitCommonOMPParallelDirective(CodeGenFunction &CGF,
843                                            const OMPExecutableDirective &S,
844                                            OpenMPDirectiveKind InnermostKind,
845                                            const RegionCodeGenTy &CodeGen) {
846   auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
847   llvm::SmallVector<llvm::Value *, 16> CapturedVars;
848   CGF.GenerateOpenMPCapturedVars(*CS, CapturedVars);
849   auto OutlinedFn = CGF.CGM.getOpenMPRuntime().emitParallelOutlinedFunction(
850       S, *CS->getCapturedDecl()->param_begin(), InnermostKind, CodeGen);
851   if (const auto *NumThreadsClause = S.getSingleClause<OMPNumThreadsClause>()) {
852     CodeGenFunction::RunCleanupsScope NumThreadsScope(CGF);
853     auto NumThreads = CGF.EmitScalarExpr(NumThreadsClause->getNumThreads(),
854                                          /*IgnoreResultAssign*/ true);
855     CGF.CGM.getOpenMPRuntime().emitNumThreadsClause(
856         CGF, NumThreads, NumThreadsClause->getLocStart());
857   }
858   if (const auto *ProcBindClause = S.getSingleClause<OMPProcBindClause>()) {
859     CodeGenFunction::RunCleanupsScope NumThreadsScope(CGF);
860     CGF.CGM.getOpenMPRuntime().emitProcBindClause(
861         CGF, ProcBindClause->getProcBindKind(), ProcBindClause->getLocStart());
862   }
863   const Expr *IfCond = nullptr;
864   for (const auto *C : S.getClausesOfKind<OMPIfClause>()) {
865     if (C->getNameModifier() == OMPD_unknown ||
866         C->getNameModifier() == OMPD_parallel) {
867       IfCond = C->getCondition();
868       break;
869     }
870   }
871   CGF.CGM.getOpenMPRuntime().emitParallelCall(CGF, S.getLocStart(), OutlinedFn,
872                                               CapturedVars, IfCond);
873 }
874 
EmitOMPParallelDirective(const OMPParallelDirective & S)875 void CodeGenFunction::EmitOMPParallelDirective(const OMPParallelDirective &S) {
876   LexicalScope Scope(*this, S.getSourceRange());
877   // Emit parallel region as a standalone region.
878   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
879     OMPPrivateScope PrivateScope(CGF);
880     bool Copyins = CGF.EmitOMPCopyinClause(S);
881     bool Firstprivates = CGF.EmitOMPFirstprivateClause(S, PrivateScope);
882     if (Copyins || Firstprivates) {
883       // Emit implicit barrier to synchronize threads and avoid data races on
884       // initialization of firstprivate variables or propagation master's thread
885       // values of threadprivate variables to local instances of that variables
886       // of all other implicit threads.
887       CGF.CGM.getOpenMPRuntime().emitBarrierCall(
888           CGF, S.getLocStart(), OMPD_unknown, /*EmitChecks=*/false,
889           /*ForceSimpleCall=*/true);
890     }
891     CGF.EmitOMPPrivateClause(S, PrivateScope);
892     CGF.EmitOMPReductionClauseInit(S, PrivateScope);
893     (void)PrivateScope.Privatize();
894     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
895     CGF.EmitOMPReductionClauseFinal(S);
896   };
897   emitCommonOMPParallelDirective(*this, S, OMPD_parallel, CodeGen);
898 }
899 
EmitOMPLoopBody(const OMPLoopDirective & D,JumpDest LoopExit)900 void CodeGenFunction::EmitOMPLoopBody(const OMPLoopDirective &D,
901                                       JumpDest LoopExit) {
902   RunCleanupsScope BodyScope(*this);
903   // Update counters values on current iteration.
904   for (auto I : D.updates()) {
905     EmitIgnoredExpr(I);
906   }
907   // Update the linear variables.
908   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
909     for (auto U : C->updates()) {
910       EmitIgnoredExpr(U);
911     }
912   }
913 
914   // On a continue in the body, jump to the end.
915   auto Continue = getJumpDestInCurrentScope("omp.body.continue");
916   BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
917   // Emit loop body.
918   EmitStmt(D.getBody());
919   // The end (updates/cleanups).
920   EmitBlock(Continue.getBlock());
921   BreakContinueStack.pop_back();
922     // TODO: Update lastprivates if the SeparateIter flag is true.
923     // This will be implemented in a follow-up OMPLastprivateClause patch, but
924     // result should be still correct without it, as we do not make these
925     // variables private yet.
926 }
927 
EmitOMPInnerLoop(const Stmt & S,bool RequiresCleanup,const Expr * LoopCond,const Expr * IncExpr,const llvm::function_ref<void (CodeGenFunction &)> & BodyGen,const llvm::function_ref<void (CodeGenFunction &)> & PostIncGen)928 void CodeGenFunction::EmitOMPInnerLoop(
929     const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
930     const Expr *IncExpr,
931     const llvm::function_ref<void(CodeGenFunction &)> &BodyGen,
932     const llvm::function_ref<void(CodeGenFunction &)> &PostIncGen) {
933   auto LoopExit = getJumpDestInCurrentScope("omp.inner.for.end");
934 
935   // Start the loop with a block that tests the condition.
936   auto CondBlock = createBasicBlock("omp.inner.for.cond");
937   EmitBlock(CondBlock);
938   LoopStack.push(CondBlock);
939 
940   // If there are any cleanups between here and the loop-exit scope,
941   // create a block to stage a loop exit along.
942   auto ExitBlock = LoopExit.getBlock();
943   if (RequiresCleanup)
944     ExitBlock = createBasicBlock("omp.inner.for.cond.cleanup");
945 
946   auto LoopBody = createBasicBlock("omp.inner.for.body");
947 
948   // Emit condition.
949   EmitBranchOnBoolExpr(LoopCond, LoopBody, ExitBlock, getProfileCount(&S));
950   if (ExitBlock != LoopExit.getBlock()) {
951     EmitBlock(ExitBlock);
952     EmitBranchThroughCleanup(LoopExit);
953   }
954 
955   EmitBlock(LoopBody);
956   incrementProfileCounter(&S);
957 
958   // Create a block for the increment.
959   auto Continue = getJumpDestInCurrentScope("omp.inner.for.inc");
960   BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
961 
962   BodyGen(*this);
963 
964   // Emit "IV = IV + 1" and a back-edge to the condition block.
965   EmitBlock(Continue.getBlock());
966   EmitIgnoredExpr(IncExpr);
967   PostIncGen(*this);
968   BreakContinueStack.pop_back();
969   EmitBranch(CondBlock);
970   LoopStack.pop();
971   // Emit the fall-through block.
972   EmitBlock(LoopExit.getBlock());
973 }
974 
EmitOMPLinearClauseInit(const OMPLoopDirective & D)975 void CodeGenFunction::EmitOMPLinearClauseInit(const OMPLoopDirective &D) {
976   if (!HaveInsertPoint())
977     return;
978   // Emit inits for the linear variables.
979   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
980     for (auto Init : C->inits()) {
981       auto *VD = cast<VarDecl>(cast<DeclRefExpr>(Init)->getDecl());
982       auto *OrigVD = cast<VarDecl>(
983           cast<DeclRefExpr>(VD->getInit()->IgnoreImpCasts())->getDecl());
984       DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
985                       CapturedStmtInfo->lookup(OrigVD) != nullptr,
986                       VD->getInit()->getType(), VK_LValue,
987                       VD->getInit()->getExprLoc());
988       AutoVarEmission Emission = EmitAutoVarAlloca(*VD);
989       EmitExprAsInit(&DRE, VD,
990                MakeAddrLValue(Emission.getAllocatedAddress(), VD->getType()),
991                      /*capturedByInit=*/false);
992       EmitAutoVarCleanups(Emission);
993     }
994     // Emit the linear steps for the linear clauses.
995     // If a step is not constant, it is pre-calculated before the loop.
996     if (auto CS = cast_or_null<BinaryOperator>(C->getCalcStep()))
997       if (auto SaveRef = cast<DeclRefExpr>(CS->getLHS())) {
998         EmitVarDecl(*cast<VarDecl>(SaveRef->getDecl()));
999         // Emit calculation of the linear step.
1000         EmitIgnoredExpr(CS);
1001       }
1002   }
1003 }
1004 
emitLinearClauseFinal(CodeGenFunction & CGF,const OMPLoopDirective & D)1005 static void emitLinearClauseFinal(CodeGenFunction &CGF,
1006                                   const OMPLoopDirective &D) {
1007   if (!CGF.HaveInsertPoint())
1008     return;
1009   // Emit the final values of the linear variables.
1010   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
1011     auto IC = C->varlist_begin();
1012     for (auto F : C->finals()) {
1013       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IC)->getDecl());
1014       DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
1015                       CGF.CapturedStmtInfo->lookup(OrigVD) != nullptr,
1016                       (*IC)->getType(), VK_LValue, (*IC)->getExprLoc());
1017       Address OrigAddr = CGF.EmitLValue(&DRE).getAddress();
1018       CodeGenFunction::OMPPrivateScope VarScope(CGF);
1019       VarScope.addPrivate(OrigVD,
1020                           [OrigAddr]() -> Address { return OrigAddr; });
1021       (void)VarScope.Privatize();
1022       CGF.EmitIgnoredExpr(F);
1023       ++IC;
1024     }
1025   }
1026 }
1027 
emitAlignedClause(CodeGenFunction & CGF,const OMPExecutableDirective & D)1028 static void emitAlignedClause(CodeGenFunction &CGF,
1029                               const OMPExecutableDirective &D) {
1030   if (!CGF.HaveInsertPoint())
1031     return;
1032   for (const auto *Clause : D.getClausesOfKind<OMPAlignedClause>()) {
1033     unsigned ClauseAlignment = 0;
1034     if (auto AlignmentExpr = Clause->getAlignment()) {
1035       auto AlignmentCI =
1036           cast<llvm::ConstantInt>(CGF.EmitScalarExpr(AlignmentExpr));
1037       ClauseAlignment = static_cast<unsigned>(AlignmentCI->getZExtValue());
1038     }
1039     for (auto E : Clause->varlists()) {
1040       unsigned Alignment = ClauseAlignment;
1041       if (Alignment == 0) {
1042         // OpenMP [2.8.1, Description]
1043         // If no optional parameter is specified, implementation-defined default
1044         // alignments for SIMD instructions on the target platforms are assumed.
1045         Alignment =
1046             CGF.getContext()
1047                 .toCharUnitsFromBits(CGF.getContext().getOpenMPDefaultSimdAlign(
1048                     E->getType()->getPointeeType()))
1049                 .getQuantity();
1050       }
1051       assert((Alignment == 0 || llvm::isPowerOf2_32(Alignment)) &&
1052              "alignment is not power of 2");
1053       if (Alignment != 0) {
1054         llvm::Value *PtrValue = CGF.EmitScalarExpr(E);
1055         CGF.EmitAlignmentAssumption(PtrValue, Alignment);
1056       }
1057     }
1058   }
1059 }
1060 
emitPrivateLoopCounters(CodeGenFunction & CGF,CodeGenFunction::OMPPrivateScope & LoopScope,ArrayRef<Expr * > Counters,ArrayRef<Expr * > PrivateCounters)1061 static void emitPrivateLoopCounters(CodeGenFunction &CGF,
1062                                     CodeGenFunction::OMPPrivateScope &LoopScope,
1063                                     ArrayRef<Expr *> Counters,
1064                                     ArrayRef<Expr *> PrivateCounters) {
1065   if (!CGF.HaveInsertPoint())
1066     return;
1067   auto I = PrivateCounters.begin();
1068   for (auto *E : Counters) {
1069     auto *VD = cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl());
1070     auto *PrivateVD = cast<VarDecl>(cast<DeclRefExpr>(*I)->getDecl());
1071     Address Addr = Address::invalid();
1072     (void)LoopScope.addPrivate(PrivateVD, [&]() -> Address {
1073       // Emit var without initialization.
1074       auto VarEmission = CGF.EmitAutoVarAlloca(*PrivateVD);
1075       CGF.EmitAutoVarCleanups(VarEmission);
1076       Addr = VarEmission.getAllocatedAddress();
1077       return Addr;
1078     });
1079     (void)LoopScope.addPrivate(VD, [&]() -> Address { return Addr; });
1080     ++I;
1081   }
1082 }
1083 
emitPreCond(CodeGenFunction & CGF,const OMPLoopDirective & S,const Expr * Cond,llvm::BasicBlock * TrueBlock,llvm::BasicBlock * FalseBlock,uint64_t TrueCount)1084 static void emitPreCond(CodeGenFunction &CGF, const OMPLoopDirective &S,
1085                         const Expr *Cond, llvm::BasicBlock *TrueBlock,
1086                         llvm::BasicBlock *FalseBlock, uint64_t TrueCount) {
1087   if (!CGF.HaveInsertPoint())
1088     return;
1089   {
1090     CodeGenFunction::OMPPrivateScope PreCondScope(CGF);
1091     emitPrivateLoopCounters(CGF, PreCondScope, S.counters(),
1092                             S.private_counters());
1093     (void)PreCondScope.Privatize();
1094     // Get initial values of real counters.
1095     for (auto I : S.inits()) {
1096       CGF.EmitIgnoredExpr(I);
1097     }
1098   }
1099   // Check that loop is executed at least one time.
1100   CGF.EmitBranchOnBoolExpr(Cond, TrueBlock, FalseBlock, TrueCount);
1101 }
1102 
1103 static void
emitPrivateLinearVars(CodeGenFunction & CGF,const OMPExecutableDirective & D,CodeGenFunction::OMPPrivateScope & PrivateScope)1104 emitPrivateLinearVars(CodeGenFunction &CGF, const OMPExecutableDirective &D,
1105                       CodeGenFunction::OMPPrivateScope &PrivateScope) {
1106   if (!CGF.HaveInsertPoint())
1107     return;
1108   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
1109     auto CurPrivate = C->privates().begin();
1110     for (auto *E : C->varlists()) {
1111       auto *VD = cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl());
1112       auto *PrivateVD =
1113           cast<VarDecl>(cast<DeclRefExpr>(*CurPrivate)->getDecl());
1114       bool IsRegistered = PrivateScope.addPrivate(VD, [&]() -> Address {
1115         // Emit private VarDecl with copy init.
1116         CGF.EmitVarDecl(*PrivateVD);
1117         return CGF.GetAddrOfLocalVar(PrivateVD);
1118       });
1119       assert(IsRegistered && "linear var already registered as private");
1120       // Silence the warning about unused variable.
1121       (void)IsRegistered;
1122       ++CurPrivate;
1123     }
1124   }
1125 }
1126 
emitSimdlenSafelenClause(CodeGenFunction & CGF,const OMPExecutableDirective & D)1127 static void emitSimdlenSafelenClause(CodeGenFunction &CGF,
1128                                      const OMPExecutableDirective &D) {
1129   if (!CGF.HaveInsertPoint())
1130     return;
1131   if (const auto *C = D.getSingleClause<OMPSimdlenClause>()) {
1132     RValue Len = CGF.EmitAnyExpr(C->getSimdlen(), AggValueSlot::ignored(),
1133                                  /*ignoreResult=*/true);
1134     llvm::ConstantInt *Val = cast<llvm::ConstantInt>(Len.getScalarVal());
1135     CGF.LoopStack.setVectorizeWidth(Val->getZExtValue());
1136     // In presence of finite 'safelen', it may be unsafe to mark all
1137     // the memory instructions parallel, because loop-carried
1138     // dependences of 'safelen' iterations are possible.
1139     CGF.LoopStack.setParallel(!D.getSingleClause<OMPSafelenClause>());
1140   } else if (const auto *C = D.getSingleClause<OMPSafelenClause>()) {
1141     RValue Len = CGF.EmitAnyExpr(C->getSafelen(), AggValueSlot::ignored(),
1142                                  /*ignoreResult=*/true);
1143     llvm::ConstantInt *Val = cast<llvm::ConstantInt>(Len.getScalarVal());
1144     CGF.LoopStack.setVectorizeWidth(Val->getZExtValue());
1145     // In presence of finite 'safelen', it may be unsafe to mark all
1146     // the memory instructions parallel, because loop-carried
1147     // dependences of 'safelen' iterations are possible.
1148     CGF.LoopStack.setParallel(false);
1149   }
1150 }
1151 
EmitOMPSimdInit(const OMPLoopDirective & D)1152 void CodeGenFunction::EmitOMPSimdInit(const OMPLoopDirective &D) {
1153   // Walk clauses and process safelen/lastprivate.
1154   LoopStack.setParallel();
1155   LoopStack.setVectorizeEnable(true);
1156   emitSimdlenSafelenClause(*this, D);
1157 }
1158 
EmitOMPSimdFinal(const OMPLoopDirective & D)1159 void CodeGenFunction::EmitOMPSimdFinal(const OMPLoopDirective &D) {
1160   if (!HaveInsertPoint())
1161     return;
1162   auto IC = D.counters().begin();
1163   for (auto F : D.finals()) {
1164     auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>((*IC))->getDecl());
1165     if (LocalDeclMap.count(OrigVD) || CapturedStmtInfo->lookup(OrigVD)) {
1166       DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
1167                       CapturedStmtInfo->lookup(OrigVD) != nullptr,
1168                       (*IC)->getType(), VK_LValue, (*IC)->getExprLoc());
1169       Address OrigAddr = EmitLValue(&DRE).getAddress();
1170       OMPPrivateScope VarScope(*this);
1171       VarScope.addPrivate(OrigVD,
1172                           [OrigAddr]() -> Address { return OrigAddr; });
1173       (void)VarScope.Privatize();
1174       EmitIgnoredExpr(F);
1175     }
1176     ++IC;
1177   }
1178   emitLinearClauseFinal(*this, D);
1179 }
1180 
EmitOMPSimdDirective(const OMPSimdDirective & S)1181 void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
1182   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1183     // if (PreCond) {
1184     //   for (IV in 0..LastIteration) BODY;
1185     //   <Final counter/linear vars updates>;
1186     // }
1187     //
1188 
1189     // Emit: if (PreCond) - begin.
1190     // If the condition constant folds and can be elided, avoid emitting the
1191     // whole loop.
1192     bool CondConstant;
1193     llvm::BasicBlock *ContBlock = nullptr;
1194     if (CGF.ConstantFoldsToSimpleInteger(S.getPreCond(), CondConstant)) {
1195       if (!CondConstant)
1196         return;
1197     } else {
1198       auto *ThenBlock = CGF.createBasicBlock("simd.if.then");
1199       ContBlock = CGF.createBasicBlock("simd.if.end");
1200       emitPreCond(CGF, S, S.getPreCond(), ThenBlock, ContBlock,
1201                   CGF.getProfileCount(&S));
1202       CGF.EmitBlock(ThenBlock);
1203       CGF.incrementProfileCounter(&S);
1204     }
1205 
1206     // Emit the loop iteration variable.
1207     const Expr *IVExpr = S.getIterationVariable();
1208     const VarDecl *IVDecl = cast<VarDecl>(cast<DeclRefExpr>(IVExpr)->getDecl());
1209     CGF.EmitVarDecl(*IVDecl);
1210     CGF.EmitIgnoredExpr(S.getInit());
1211 
1212     // Emit the iterations count variable.
1213     // If it is not a variable, Sema decided to calculate iterations count on
1214     // each iteration (e.g., it is foldable into a constant).
1215     if (auto LIExpr = dyn_cast<DeclRefExpr>(S.getLastIteration())) {
1216       CGF.EmitVarDecl(*cast<VarDecl>(LIExpr->getDecl()));
1217       // Emit calculation of the iterations count.
1218       CGF.EmitIgnoredExpr(S.getCalcLastIteration());
1219     }
1220 
1221     CGF.EmitOMPSimdInit(S);
1222 
1223     emitAlignedClause(CGF, S);
1224     CGF.EmitOMPLinearClauseInit(S);
1225     bool HasLastprivateClause;
1226     {
1227       OMPPrivateScope LoopScope(CGF);
1228       emitPrivateLoopCounters(CGF, LoopScope, S.counters(),
1229                               S.private_counters());
1230       emitPrivateLinearVars(CGF, S, LoopScope);
1231       CGF.EmitOMPPrivateClause(S, LoopScope);
1232       CGF.EmitOMPReductionClauseInit(S, LoopScope);
1233       HasLastprivateClause = CGF.EmitOMPLastprivateClauseInit(S, LoopScope);
1234       (void)LoopScope.Privatize();
1235       CGF.EmitOMPInnerLoop(S, LoopScope.requiresCleanups(), S.getCond(),
1236                            S.getInc(),
1237                            [&S](CodeGenFunction &CGF) {
1238                              CGF.EmitOMPLoopBody(S, JumpDest());
1239                              CGF.EmitStopPoint(&S);
1240                            },
1241                            [](CodeGenFunction &) {});
1242       // Emit final copy of the lastprivate variables at the end of loops.
1243       if (HasLastprivateClause) {
1244         CGF.EmitOMPLastprivateClauseFinal(S);
1245       }
1246       CGF.EmitOMPReductionClauseFinal(S);
1247     }
1248     CGF.EmitOMPSimdFinal(S);
1249     // Emit: if (PreCond) - end.
1250     if (ContBlock) {
1251       CGF.EmitBranch(ContBlock);
1252       CGF.EmitBlock(ContBlock, true);
1253     }
1254   };
1255   CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_simd, CodeGen);
1256 }
1257 
EmitOMPForOuterLoop(OpenMPScheduleClauseKind ScheduleKind,const OMPLoopDirective & S,OMPPrivateScope & LoopScope,bool Ordered,Address LB,Address UB,Address ST,Address IL,llvm::Value * Chunk)1258 void CodeGenFunction::EmitOMPForOuterLoop(OpenMPScheduleClauseKind ScheduleKind,
1259                                           const OMPLoopDirective &S,
1260                                           OMPPrivateScope &LoopScope,
1261                                           bool Ordered, Address LB,
1262                                           Address UB, Address ST,
1263                                           Address IL, llvm::Value *Chunk) {
1264   auto &RT = CGM.getOpenMPRuntime();
1265 
1266   // Dynamic scheduling of the outer loop (dynamic, guided, auto, runtime).
1267   const bool DynamicOrOrdered = Ordered || RT.isDynamic(ScheduleKind);
1268 
1269   assert((Ordered ||
1270           !RT.isStaticNonchunked(ScheduleKind, /*Chunked=*/Chunk != nullptr)) &&
1271          "static non-chunked schedule does not need outer loop");
1272 
1273   // Emit outer loop.
1274   //
1275   // OpenMP [2.7.1, Loop Construct, Description, table 2-1]
1276   // When schedule(dynamic,chunk_size) is specified, the iterations are
1277   // distributed to threads in the team in chunks as the threads request them.
1278   // Each thread executes a chunk of iterations, then requests another chunk,
1279   // until no chunks remain to be distributed. Each chunk contains chunk_size
1280   // iterations, except for the last chunk to be distributed, which may have
1281   // fewer iterations. When no chunk_size is specified, it defaults to 1.
1282   //
1283   // When schedule(guided,chunk_size) is specified, the iterations are assigned
1284   // to threads in the team in chunks as the executing threads request them.
1285   // Each thread executes a chunk of iterations, then requests another chunk,
1286   // until no chunks remain to be assigned. For a chunk_size of 1, the size of
1287   // each chunk is proportional to the number of unassigned iterations divided
1288   // by the number of threads in the team, decreasing to 1. For a chunk_size
1289   // with value k (greater than 1), the size of each chunk is determined in the
1290   // same way, with the restriction that the chunks do not contain fewer than k
1291   // iterations (except for the last chunk to be assigned, which may have fewer
1292   // than k iterations).
1293   //
1294   // When schedule(auto) is specified, the decision regarding scheduling is
1295   // delegated to the compiler and/or runtime system. The programmer gives the
1296   // implementation the freedom to choose any possible mapping of iterations to
1297   // threads in the team.
1298   //
1299   // When schedule(runtime) is specified, the decision regarding scheduling is
1300   // deferred until run time, and the schedule and chunk size are taken from the
1301   // run-sched-var ICV. If the ICV is set to auto, the schedule is
1302   // implementation defined
1303   //
1304   // while(__kmpc_dispatch_next(&LB, &UB)) {
1305   //   idx = LB;
1306   //   while (idx <= UB) { BODY; ++idx;
1307   //   __kmpc_dispatch_fini_(4|8)[u](); // For ordered loops only.
1308   //   } // inner loop
1309   // }
1310   //
1311   // OpenMP [2.7.1, Loop Construct, Description, table 2-1]
1312   // When schedule(static, chunk_size) is specified, iterations are divided into
1313   // chunks of size chunk_size, and the chunks are assigned to the threads in
1314   // the team in a round-robin fashion in the order of the thread number.
1315   //
1316   // while(UB = min(UB, GlobalUB), idx = LB, idx < UB) {
1317   //   while (idx <= UB) { BODY; ++idx; } // inner loop
1318   //   LB = LB + ST;
1319   //   UB = UB + ST;
1320   // }
1321   //
1322 
1323   const Expr *IVExpr = S.getIterationVariable();
1324   const unsigned IVSize = getContext().getTypeSize(IVExpr->getType());
1325   const bool IVSigned = IVExpr->getType()->hasSignedIntegerRepresentation();
1326 
1327   if (DynamicOrOrdered) {
1328     llvm::Value *UBVal = EmitScalarExpr(S.getLastIteration());
1329     RT.emitForDispatchInit(*this, S.getLocStart(), ScheduleKind,
1330                            IVSize, IVSigned, Ordered, UBVal, Chunk);
1331   } else {
1332     RT.emitForStaticInit(*this, S.getLocStart(), ScheduleKind,
1333                          IVSize, IVSigned, Ordered, IL, LB, UB, ST, Chunk);
1334   }
1335 
1336   auto LoopExit = getJumpDestInCurrentScope("omp.dispatch.end");
1337 
1338   // Start the loop with a block that tests the condition.
1339   auto CondBlock = createBasicBlock("omp.dispatch.cond");
1340   EmitBlock(CondBlock);
1341   LoopStack.push(CondBlock);
1342 
1343   llvm::Value *BoolCondVal = nullptr;
1344   if (!DynamicOrOrdered) {
1345     // UB = min(UB, GlobalUB)
1346     EmitIgnoredExpr(S.getEnsureUpperBound());
1347     // IV = LB
1348     EmitIgnoredExpr(S.getInit());
1349     // IV < UB
1350     BoolCondVal = EvaluateExprAsBool(S.getCond());
1351   } else {
1352     BoolCondVal = RT.emitForNext(*this, S.getLocStart(), IVSize, IVSigned,
1353                                     IL, LB, UB, ST);
1354   }
1355 
1356   // If there are any cleanups between here and the loop-exit scope,
1357   // create a block to stage a loop exit along.
1358   auto ExitBlock = LoopExit.getBlock();
1359   if (LoopScope.requiresCleanups())
1360     ExitBlock = createBasicBlock("omp.dispatch.cleanup");
1361 
1362   auto LoopBody = createBasicBlock("omp.dispatch.body");
1363   Builder.CreateCondBr(BoolCondVal, LoopBody, ExitBlock);
1364   if (ExitBlock != LoopExit.getBlock()) {
1365     EmitBlock(ExitBlock);
1366     EmitBranchThroughCleanup(LoopExit);
1367   }
1368   EmitBlock(LoopBody);
1369 
1370   // Emit "IV = LB" (in case of static schedule, we have already calculated new
1371   // LB for loop condition and emitted it above).
1372   if (DynamicOrOrdered)
1373     EmitIgnoredExpr(S.getInit());
1374 
1375   // Create a block for the increment.
1376   auto Continue = getJumpDestInCurrentScope("omp.dispatch.inc");
1377   BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
1378 
1379   // Generate !llvm.loop.parallel metadata for loads and stores for loops
1380   // with dynamic/guided scheduling and without ordered clause.
1381   if (!isOpenMPSimdDirective(S.getDirectiveKind())) {
1382     LoopStack.setParallel((ScheduleKind == OMPC_SCHEDULE_dynamic ||
1383                            ScheduleKind == OMPC_SCHEDULE_guided) &&
1384                           !Ordered);
1385   } else {
1386     EmitOMPSimdInit(S);
1387   }
1388 
1389   SourceLocation Loc = S.getLocStart();
1390   EmitOMPInnerLoop(S, LoopScope.requiresCleanups(), S.getCond(), S.getInc(),
1391                    [&S, LoopExit](CodeGenFunction &CGF) {
1392                      CGF.EmitOMPLoopBody(S, LoopExit);
1393                      CGF.EmitStopPoint(&S);
1394                    },
1395                    [Ordered, IVSize, IVSigned, Loc](CodeGenFunction &CGF) {
1396                      if (Ordered) {
1397                        CGF.CGM.getOpenMPRuntime().emitForOrderedIterationEnd(
1398                            CGF, Loc, IVSize, IVSigned);
1399                      }
1400                    });
1401 
1402   EmitBlock(Continue.getBlock());
1403   BreakContinueStack.pop_back();
1404   if (!DynamicOrOrdered) {
1405     // Emit "LB = LB + Stride", "UB = UB + Stride".
1406     EmitIgnoredExpr(S.getNextLowerBound());
1407     EmitIgnoredExpr(S.getNextUpperBound());
1408   }
1409 
1410   EmitBranch(CondBlock);
1411   LoopStack.pop();
1412   // Emit the fall-through block.
1413   EmitBlock(LoopExit.getBlock());
1414 
1415   // Tell the runtime we are done.
1416   if (!DynamicOrOrdered)
1417     RT.emitForStaticFinish(*this, S.getLocEnd());
1418 }
1419 
1420 /// \brief Emit a helper variable and return corresponding lvalue.
EmitOMPHelperVar(CodeGenFunction & CGF,const DeclRefExpr * Helper)1421 static LValue EmitOMPHelperVar(CodeGenFunction &CGF,
1422                                const DeclRefExpr *Helper) {
1423   auto VDecl = cast<VarDecl>(Helper->getDecl());
1424   CGF.EmitVarDecl(*VDecl);
1425   return CGF.EmitLValue(Helper);
1426 }
1427 
1428 static std::pair<llvm::Value * /*Chunk*/, OpenMPScheduleClauseKind>
emitScheduleClause(CodeGenFunction & CGF,const OMPLoopDirective & S,bool OuterRegion)1429 emitScheduleClause(CodeGenFunction &CGF, const OMPLoopDirective &S,
1430                    bool OuterRegion) {
1431   // Detect the loop schedule kind and chunk.
1432   auto ScheduleKind = OMPC_SCHEDULE_unknown;
1433   llvm::Value *Chunk = nullptr;
1434   if (const auto *C = S.getSingleClause<OMPScheduleClause>()) {
1435     ScheduleKind = C->getScheduleKind();
1436     if (const auto *Ch = C->getChunkSize()) {
1437       if (auto *ImpRef = cast_or_null<DeclRefExpr>(C->getHelperChunkSize())) {
1438         if (OuterRegion) {
1439           const VarDecl *ImpVar = cast<VarDecl>(ImpRef->getDecl());
1440           CGF.EmitVarDecl(*ImpVar);
1441           CGF.EmitStoreThroughLValue(
1442               CGF.EmitAnyExpr(Ch),
1443               CGF.MakeAddrLValue(CGF.GetAddrOfLocalVar(ImpVar),
1444                                  ImpVar->getType()));
1445         } else {
1446           Ch = ImpRef;
1447         }
1448       }
1449       if (!C->getHelperChunkSize() || !OuterRegion) {
1450         Chunk = CGF.EmitScalarExpr(Ch);
1451         Chunk = CGF.EmitScalarConversion(Chunk, Ch->getType(),
1452                                          S.getIterationVariable()->getType(),
1453                                          S.getLocStart());
1454       }
1455     }
1456   }
1457   return std::make_pair(Chunk, ScheduleKind);
1458 }
1459 
EmitOMPWorksharingLoop(const OMPLoopDirective & S)1460 bool CodeGenFunction::EmitOMPWorksharingLoop(const OMPLoopDirective &S) {
1461   // Emit the loop iteration variable.
1462   auto IVExpr = cast<DeclRefExpr>(S.getIterationVariable());
1463   auto IVDecl = cast<VarDecl>(IVExpr->getDecl());
1464   EmitVarDecl(*IVDecl);
1465 
1466   // Emit the iterations count variable.
1467   // If it is not a variable, Sema decided to calculate iterations count on each
1468   // iteration (e.g., it is foldable into a constant).
1469   if (auto LIExpr = dyn_cast<DeclRefExpr>(S.getLastIteration())) {
1470     EmitVarDecl(*cast<VarDecl>(LIExpr->getDecl()));
1471     // Emit calculation of the iterations count.
1472     EmitIgnoredExpr(S.getCalcLastIteration());
1473   }
1474 
1475   auto &RT = CGM.getOpenMPRuntime();
1476 
1477   bool HasLastprivateClause;
1478   // Check pre-condition.
1479   {
1480     // Skip the entire loop if we don't meet the precondition.
1481     // If the condition constant folds and can be elided, avoid emitting the
1482     // whole loop.
1483     bool CondConstant;
1484     llvm::BasicBlock *ContBlock = nullptr;
1485     if (ConstantFoldsToSimpleInteger(S.getPreCond(), CondConstant)) {
1486       if (!CondConstant)
1487         return false;
1488     } else {
1489       auto *ThenBlock = createBasicBlock("omp.precond.then");
1490       ContBlock = createBasicBlock("omp.precond.end");
1491       emitPreCond(*this, S, S.getPreCond(), ThenBlock, ContBlock,
1492                   getProfileCount(&S));
1493       EmitBlock(ThenBlock);
1494       incrementProfileCounter(&S);
1495     }
1496 
1497     emitAlignedClause(*this, S);
1498     EmitOMPLinearClauseInit(S);
1499     // Emit 'then' code.
1500     {
1501       // Emit helper vars inits.
1502       LValue LB =
1503           EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getLowerBoundVariable()));
1504       LValue UB =
1505           EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getUpperBoundVariable()));
1506       LValue ST =
1507           EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getStrideVariable()));
1508       LValue IL =
1509           EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getIsLastIterVariable()));
1510 
1511       OMPPrivateScope LoopScope(*this);
1512       if (EmitOMPFirstprivateClause(S, LoopScope)) {
1513         // Emit implicit barrier to synchronize threads and avoid data races on
1514         // initialization of firstprivate variables.
1515         CGM.getOpenMPRuntime().emitBarrierCall(
1516             *this, S.getLocStart(), OMPD_unknown, /*EmitChecks=*/false,
1517             /*ForceSimpleCall=*/true);
1518       }
1519       EmitOMPPrivateClause(S, LoopScope);
1520       HasLastprivateClause = EmitOMPLastprivateClauseInit(S, LoopScope);
1521       EmitOMPReductionClauseInit(S, LoopScope);
1522       emitPrivateLoopCounters(*this, LoopScope, S.counters(),
1523                               S.private_counters());
1524       emitPrivateLinearVars(*this, S, LoopScope);
1525       (void)LoopScope.Privatize();
1526 
1527       // Detect the loop schedule kind and chunk.
1528       llvm::Value *Chunk;
1529       OpenMPScheduleClauseKind ScheduleKind;
1530       auto ScheduleInfo =
1531           emitScheduleClause(*this, S, /*OuterRegion=*/false);
1532       Chunk = ScheduleInfo.first;
1533       ScheduleKind = ScheduleInfo.second;
1534       const unsigned IVSize = getContext().getTypeSize(IVExpr->getType());
1535       const bool IVSigned = IVExpr->getType()->hasSignedIntegerRepresentation();
1536       const bool Ordered = S.getSingleClause<OMPOrderedClause>() != nullptr;
1537       if (RT.isStaticNonchunked(ScheduleKind,
1538                                 /* Chunked */ Chunk != nullptr) &&
1539           !Ordered) {
1540         if (isOpenMPSimdDirective(S.getDirectiveKind())) {
1541           EmitOMPSimdInit(S);
1542         }
1543         // OpenMP [2.7.1, Loop Construct, Description, table 2-1]
1544         // When no chunk_size is specified, the iteration space is divided into
1545         // chunks that are approximately equal in size, and at most one chunk is
1546         // distributed to each thread. Note that the size of the chunks is
1547         // unspecified in this case.
1548         RT.emitForStaticInit(*this, S.getLocStart(), ScheduleKind,
1549                              IVSize, IVSigned, Ordered,
1550                              IL.getAddress(), LB.getAddress(),
1551                              UB.getAddress(), ST.getAddress());
1552         auto LoopExit = getJumpDestInCurrentScope(createBasicBlock("omp.loop.exit"));
1553         // UB = min(UB, GlobalUB);
1554         EmitIgnoredExpr(S.getEnsureUpperBound());
1555         // IV = LB;
1556         EmitIgnoredExpr(S.getInit());
1557         // while (idx <= UB) { BODY; ++idx; }
1558         EmitOMPInnerLoop(S, LoopScope.requiresCleanups(), S.getCond(),
1559                          S.getInc(),
1560                          [&S, LoopExit](CodeGenFunction &CGF) {
1561                            CGF.EmitOMPLoopBody(S, LoopExit);
1562                            CGF.EmitStopPoint(&S);
1563                          },
1564                          [](CodeGenFunction &) {});
1565         EmitBlock(LoopExit.getBlock());
1566         // Tell the runtime we are done.
1567         RT.emitForStaticFinish(*this, S.getLocStart());
1568       } else {
1569         // Emit the outer loop, which requests its work chunk [LB..UB] from
1570         // runtime and runs the inner loop to process it.
1571         EmitOMPForOuterLoop(ScheduleKind, S, LoopScope, Ordered,
1572                             LB.getAddress(), UB.getAddress(), ST.getAddress(),
1573                             IL.getAddress(), Chunk);
1574       }
1575       EmitOMPReductionClauseFinal(S);
1576       // Emit final copy of the lastprivate variables if IsLastIter != 0.
1577       if (HasLastprivateClause)
1578         EmitOMPLastprivateClauseFinal(
1579             S, Builder.CreateIsNotNull(EmitLoadOfScalar(IL, S.getLocStart())));
1580     }
1581     if (isOpenMPSimdDirective(S.getDirectiveKind())) {
1582       EmitOMPSimdFinal(S);
1583     }
1584     // We're now done with the loop, so jump to the continuation block.
1585     if (ContBlock) {
1586       EmitBranch(ContBlock);
1587       EmitBlock(ContBlock, true);
1588     }
1589   }
1590   return HasLastprivateClause;
1591 }
1592 
EmitOMPForDirective(const OMPForDirective & S)1593 void CodeGenFunction::EmitOMPForDirective(const OMPForDirective &S) {
1594   LexicalScope Scope(*this, S.getSourceRange());
1595   bool HasLastprivates = false;
1596   auto &&CodeGen = [&S, &HasLastprivates](CodeGenFunction &CGF) {
1597     HasLastprivates = CGF.EmitOMPWorksharingLoop(S);
1598   };
1599   CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_for, CodeGen,
1600                                               S.hasCancel());
1601 
1602   // Emit an implicit barrier at the end.
1603   if (!S.getSingleClause<OMPNowaitClause>() || HasLastprivates) {
1604     CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(), OMPD_for);
1605   }
1606 }
1607 
EmitOMPForSimdDirective(const OMPForSimdDirective & S)1608 void CodeGenFunction::EmitOMPForSimdDirective(const OMPForSimdDirective &S) {
1609   LexicalScope Scope(*this, S.getSourceRange());
1610   bool HasLastprivates = false;
1611   auto &&CodeGen = [&S, &HasLastprivates](CodeGenFunction &CGF) {
1612     HasLastprivates = CGF.EmitOMPWorksharingLoop(S);
1613   };
1614   CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_simd, CodeGen);
1615 
1616   // Emit an implicit barrier at the end.
1617   if (!S.getSingleClause<OMPNowaitClause>() || HasLastprivates) {
1618     CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(), OMPD_for);
1619   }
1620 }
1621 
createSectionLVal(CodeGenFunction & CGF,QualType Ty,const Twine & Name,llvm::Value * Init=nullptr)1622 static LValue createSectionLVal(CodeGenFunction &CGF, QualType Ty,
1623                                 const Twine &Name,
1624                                 llvm::Value *Init = nullptr) {
1625   auto LVal = CGF.MakeAddrLValue(CGF.CreateMemTemp(Ty, Name), Ty);
1626   if (Init)
1627     CGF.EmitScalarInit(Init, LVal);
1628   return LVal;
1629 }
1630 
1631 OpenMPDirectiveKind
EmitSections(const OMPExecutableDirective & S)1632 CodeGenFunction::EmitSections(const OMPExecutableDirective &S) {
1633   auto *Stmt = cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt();
1634   auto *CS = dyn_cast<CompoundStmt>(Stmt);
1635   if (CS && CS->size() > 1) {
1636     bool HasLastprivates = false;
1637     auto &&CodeGen = [&S, CS, &HasLastprivates](CodeGenFunction &CGF) {
1638       auto &C = CGF.CGM.getContext();
1639       auto KmpInt32Ty = C.getIntTypeForBitwidth(/*DestWidth=*/32, /*Signed=*/1);
1640       // Emit helper vars inits.
1641       LValue LB = createSectionLVal(CGF, KmpInt32Ty, ".omp.sections.lb.",
1642                                     CGF.Builder.getInt32(0));
1643       auto *GlobalUBVal = CGF.Builder.getInt32(CS->size() - 1);
1644       LValue UB =
1645           createSectionLVal(CGF, KmpInt32Ty, ".omp.sections.ub.", GlobalUBVal);
1646       LValue ST = createSectionLVal(CGF, KmpInt32Ty, ".omp.sections.st.",
1647                                     CGF.Builder.getInt32(1));
1648       LValue IL = createSectionLVal(CGF, KmpInt32Ty, ".omp.sections.il.",
1649                                     CGF.Builder.getInt32(0));
1650       // Loop counter.
1651       LValue IV = createSectionLVal(CGF, KmpInt32Ty, ".omp.sections.iv.");
1652       OpaqueValueExpr IVRefExpr(S.getLocStart(), KmpInt32Ty, VK_LValue);
1653       CodeGenFunction::OpaqueValueMapping OpaqueIV(CGF, &IVRefExpr, IV);
1654       OpaqueValueExpr UBRefExpr(S.getLocStart(), KmpInt32Ty, VK_LValue);
1655       CodeGenFunction::OpaqueValueMapping OpaqueUB(CGF, &UBRefExpr, UB);
1656       // Generate condition for loop.
1657       BinaryOperator Cond(&IVRefExpr, &UBRefExpr, BO_LE, C.BoolTy, VK_RValue,
1658                           OK_Ordinary, S.getLocStart(),
1659                           /*fpContractable=*/false);
1660       // Increment for loop counter.
1661       UnaryOperator Inc(&IVRefExpr, UO_PreInc, KmpInt32Ty, VK_RValue,
1662                         OK_Ordinary, S.getLocStart());
1663       auto BodyGen = [CS, &S, &IV](CodeGenFunction &CGF) {
1664         // Iterate through all sections and emit a switch construct:
1665         // switch (IV) {
1666         //   case 0:
1667         //     <SectionStmt[0]>;
1668         //     break;
1669         // ...
1670         //   case <NumSection> - 1:
1671         //     <SectionStmt[<NumSection> - 1]>;
1672         //     break;
1673         // }
1674         // .omp.sections.exit:
1675         auto *ExitBB = CGF.createBasicBlock(".omp.sections.exit");
1676         auto *SwitchStmt = CGF.Builder.CreateSwitch(
1677             CGF.EmitLoadOfLValue(IV, S.getLocStart()).getScalarVal(), ExitBB,
1678             CS->size());
1679         unsigned CaseNumber = 0;
1680         for (auto *SubStmt : CS->children()) {
1681           auto CaseBB = CGF.createBasicBlock(".omp.sections.case");
1682           CGF.EmitBlock(CaseBB);
1683           SwitchStmt->addCase(CGF.Builder.getInt32(CaseNumber), CaseBB);
1684           CGF.EmitStmt(SubStmt);
1685           CGF.EmitBranch(ExitBB);
1686           ++CaseNumber;
1687         }
1688         CGF.EmitBlock(ExitBB, /*IsFinished=*/true);
1689       };
1690 
1691       CodeGenFunction::OMPPrivateScope LoopScope(CGF);
1692       if (CGF.EmitOMPFirstprivateClause(S, LoopScope)) {
1693         // Emit implicit barrier to synchronize threads and avoid data races on
1694         // initialization of firstprivate variables.
1695         CGF.CGM.getOpenMPRuntime().emitBarrierCall(
1696             CGF, S.getLocStart(), OMPD_unknown, /*EmitChecks=*/false,
1697             /*ForceSimpleCall=*/true);
1698       }
1699       CGF.EmitOMPPrivateClause(S, LoopScope);
1700       HasLastprivates = CGF.EmitOMPLastprivateClauseInit(S, LoopScope);
1701       CGF.EmitOMPReductionClauseInit(S, LoopScope);
1702       (void)LoopScope.Privatize();
1703 
1704       // Emit static non-chunked loop.
1705       CGF.CGM.getOpenMPRuntime().emitForStaticInit(
1706           CGF, S.getLocStart(), OMPC_SCHEDULE_static, /*IVSize=*/32,
1707           /*IVSigned=*/true, /*Ordered=*/false, IL.getAddress(),
1708           LB.getAddress(), UB.getAddress(), ST.getAddress());
1709       // UB = min(UB, GlobalUB);
1710       auto *UBVal = CGF.EmitLoadOfScalar(UB, S.getLocStart());
1711       auto *MinUBGlobalUB = CGF.Builder.CreateSelect(
1712           CGF.Builder.CreateICmpSLT(UBVal, GlobalUBVal), UBVal, GlobalUBVal);
1713       CGF.EmitStoreOfScalar(MinUBGlobalUB, UB);
1714       // IV = LB;
1715       CGF.EmitStoreOfScalar(CGF.EmitLoadOfScalar(LB, S.getLocStart()), IV);
1716       // while (idx <= UB) { BODY; ++idx; }
1717       CGF.EmitOMPInnerLoop(S, /*RequiresCleanup=*/false, &Cond, &Inc, BodyGen,
1718                            [](CodeGenFunction &) {});
1719       // Tell the runtime we are done.
1720       CGF.CGM.getOpenMPRuntime().emitForStaticFinish(CGF, S.getLocStart());
1721       CGF.EmitOMPReductionClauseFinal(S);
1722 
1723       // Emit final copy of the lastprivate variables if IsLastIter != 0.
1724       if (HasLastprivates)
1725         CGF.EmitOMPLastprivateClauseFinal(
1726             S, CGF.Builder.CreateIsNotNull(
1727                    CGF.EmitLoadOfScalar(IL, S.getLocStart())));
1728     };
1729 
1730     bool HasCancel = false;
1731     if (auto *OSD = dyn_cast<OMPSectionsDirective>(&S))
1732       HasCancel = OSD->hasCancel();
1733     else if (auto *OPSD = dyn_cast<OMPParallelSectionsDirective>(&S))
1734       HasCancel = OPSD->hasCancel();
1735     CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_sections, CodeGen,
1736                                                 HasCancel);
1737     // Emit barrier for lastprivates only if 'sections' directive has 'nowait'
1738     // clause. Otherwise the barrier will be generated by the codegen for the
1739     // directive.
1740     if (HasLastprivates && S.getSingleClause<OMPNowaitClause>()) {
1741       // Emit implicit barrier to synchronize threads and avoid data races on
1742       // initialization of firstprivate variables.
1743       CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(),
1744                                              OMPD_unknown);
1745     }
1746     return OMPD_sections;
1747   }
1748   // If only one section is found - no need to generate loop, emit as a single
1749   // region.
1750   bool HasFirstprivates;
1751   // No need to generate reductions for sections with single section region, we
1752   // can use original shared variables for all operations.
1753   bool HasReductions = S.hasClausesOfKind<OMPReductionClause>();
1754   // No need to generate lastprivates for sections with single section region,
1755   // we can use original shared variable for all calculations with barrier at
1756   // the end of the sections.
1757   bool HasLastprivates = S.hasClausesOfKind<OMPLastprivateClause>();
1758   auto &&CodeGen = [Stmt, &S, &HasFirstprivates](CodeGenFunction &CGF) {
1759     CodeGenFunction::OMPPrivateScope SingleScope(CGF);
1760     HasFirstprivates = CGF.EmitOMPFirstprivateClause(S, SingleScope);
1761     CGF.EmitOMPPrivateClause(S, SingleScope);
1762     (void)SingleScope.Privatize();
1763 
1764     CGF.EmitStmt(Stmt);
1765   };
1766   CGM.getOpenMPRuntime().emitSingleRegion(*this, CodeGen, S.getLocStart(),
1767                                           llvm::None, llvm::None, llvm::None,
1768                                           llvm::None);
1769   // Emit barrier for firstprivates, lastprivates or reductions only if
1770   // 'sections' directive has 'nowait' clause. Otherwise the barrier will be
1771   // generated by the codegen for the directive.
1772   if ((HasFirstprivates || HasLastprivates || HasReductions) &&
1773       S.getSingleClause<OMPNowaitClause>()) {
1774     // Emit implicit barrier to synchronize threads and avoid data races on
1775     // initialization of firstprivate variables.
1776     CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(), OMPD_unknown,
1777                                            /*EmitChecks=*/false,
1778                                            /*ForceSimpleCall=*/true);
1779   }
1780   return OMPD_single;
1781 }
1782 
EmitOMPSectionsDirective(const OMPSectionsDirective & S)1783 void CodeGenFunction::EmitOMPSectionsDirective(const OMPSectionsDirective &S) {
1784   LexicalScope Scope(*this, S.getSourceRange());
1785   OpenMPDirectiveKind EmittedAs = EmitSections(S);
1786   // Emit an implicit barrier at the end.
1787   if (!S.getSingleClause<OMPNowaitClause>()) {
1788     CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(), EmittedAs);
1789   }
1790 }
1791 
EmitOMPSectionDirective(const OMPSectionDirective & S)1792 void CodeGenFunction::EmitOMPSectionDirective(const OMPSectionDirective &S) {
1793   LexicalScope Scope(*this, S.getSourceRange());
1794   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1795     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
1796   };
1797   CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_section, CodeGen,
1798                                               S.hasCancel());
1799 }
1800 
EmitOMPSingleDirective(const OMPSingleDirective & S)1801 void CodeGenFunction::EmitOMPSingleDirective(const OMPSingleDirective &S) {
1802   llvm::SmallVector<const Expr *, 8> CopyprivateVars;
1803   llvm::SmallVector<const Expr *, 8> DestExprs;
1804   llvm::SmallVector<const Expr *, 8> SrcExprs;
1805   llvm::SmallVector<const Expr *, 8> AssignmentOps;
1806   // Check if there are any 'copyprivate' clauses associated with this
1807   // 'single'
1808   // construct.
1809   // Build a list of copyprivate variables along with helper expressions
1810   // (<source>, <destination>, <destination>=<source> expressions)
1811   for (const auto *C : S.getClausesOfKind<OMPCopyprivateClause>()) {
1812     CopyprivateVars.append(C->varlists().begin(), C->varlists().end());
1813     DestExprs.append(C->destination_exprs().begin(),
1814                      C->destination_exprs().end());
1815     SrcExprs.append(C->source_exprs().begin(), C->source_exprs().end());
1816     AssignmentOps.append(C->assignment_ops().begin(),
1817                          C->assignment_ops().end());
1818   }
1819   LexicalScope Scope(*this, S.getSourceRange());
1820   // Emit code for 'single' region along with 'copyprivate' clauses
1821   bool HasFirstprivates;
1822   auto &&CodeGen = [&S, &HasFirstprivates](CodeGenFunction &CGF) {
1823     CodeGenFunction::OMPPrivateScope SingleScope(CGF);
1824     HasFirstprivates = CGF.EmitOMPFirstprivateClause(S, SingleScope);
1825     CGF.EmitOMPPrivateClause(S, SingleScope);
1826     (void)SingleScope.Privatize();
1827 
1828     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
1829   };
1830   CGM.getOpenMPRuntime().emitSingleRegion(*this, CodeGen, S.getLocStart(),
1831                                           CopyprivateVars, DestExprs, SrcExprs,
1832                                           AssignmentOps);
1833   // Emit an implicit barrier at the end (to avoid data race on firstprivate
1834   // init or if no 'nowait' clause was specified and no 'copyprivate' clause).
1835   if ((!S.getSingleClause<OMPNowaitClause>() || HasFirstprivates) &&
1836       CopyprivateVars.empty()) {
1837     CGM.getOpenMPRuntime().emitBarrierCall(
1838         *this, S.getLocStart(),
1839         S.getSingleClause<OMPNowaitClause>() ? OMPD_unknown : OMPD_single);
1840   }
1841 }
1842 
EmitOMPMasterDirective(const OMPMasterDirective & S)1843 void CodeGenFunction::EmitOMPMasterDirective(const OMPMasterDirective &S) {
1844   LexicalScope Scope(*this, S.getSourceRange());
1845   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1846     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
1847   };
1848   CGM.getOpenMPRuntime().emitMasterRegion(*this, CodeGen, S.getLocStart());
1849 }
1850 
EmitOMPCriticalDirective(const OMPCriticalDirective & S)1851 void CodeGenFunction::EmitOMPCriticalDirective(const OMPCriticalDirective &S) {
1852   LexicalScope Scope(*this, S.getSourceRange());
1853   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1854     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
1855   };
1856   Expr *Hint = nullptr;
1857   if (auto *HintClause = S.getSingleClause<OMPHintClause>())
1858     Hint = HintClause->getHint();
1859   CGM.getOpenMPRuntime().emitCriticalRegion(*this,
1860                                             S.getDirectiveName().getAsString(),
1861                                             CodeGen, S.getLocStart(), Hint);
1862 }
1863 
EmitOMPParallelForDirective(const OMPParallelForDirective & S)1864 void CodeGenFunction::EmitOMPParallelForDirective(
1865     const OMPParallelForDirective &S) {
1866   // Emit directive as a combined directive that consists of two implicit
1867   // directives: 'parallel' with 'for' directive.
1868   LexicalScope Scope(*this, S.getSourceRange());
1869   (void)emitScheduleClause(*this, S, /*OuterRegion=*/true);
1870   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1871     CGF.EmitOMPWorksharingLoop(S);
1872   };
1873   emitCommonOMPParallelDirective(*this, S, OMPD_for, CodeGen);
1874 }
1875 
EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective & S)1876 void CodeGenFunction::EmitOMPParallelForSimdDirective(
1877     const OMPParallelForSimdDirective &S) {
1878   // Emit directive as a combined directive that consists of two implicit
1879   // directives: 'parallel' with 'for' directive.
1880   LexicalScope Scope(*this, S.getSourceRange());
1881   (void)emitScheduleClause(*this, S, /*OuterRegion=*/true);
1882   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1883     CGF.EmitOMPWorksharingLoop(S);
1884   };
1885   emitCommonOMPParallelDirective(*this, S, OMPD_simd, CodeGen);
1886 }
1887 
EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective & S)1888 void CodeGenFunction::EmitOMPParallelSectionsDirective(
1889     const OMPParallelSectionsDirective &S) {
1890   // Emit directive as a combined directive that consists of two implicit
1891   // directives: 'parallel' with 'sections' directive.
1892   LexicalScope Scope(*this, S.getSourceRange());
1893   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
1894     (void)CGF.EmitSections(S);
1895   };
1896   emitCommonOMPParallelDirective(*this, S, OMPD_sections, CodeGen);
1897 }
1898 
EmitOMPTaskDirective(const OMPTaskDirective & S)1899 void CodeGenFunction::EmitOMPTaskDirective(const OMPTaskDirective &S) {
1900   // Emit outlined function for task construct.
1901   LexicalScope Scope(*this, S.getSourceRange());
1902   auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
1903   auto CapturedStruct = GenerateCapturedStmtArgument(*CS);
1904   auto *I = CS->getCapturedDecl()->param_begin();
1905   auto *PartId = std::next(I);
1906   // The first function argument for tasks is a thread id, the second one is a
1907   // part id (0 for tied tasks, >=0 for untied task).
1908   llvm::DenseSet<const VarDecl *> EmittedAsPrivate;
1909   // Get list of private variables.
1910   llvm::SmallVector<const Expr *, 8> PrivateVars;
1911   llvm::SmallVector<const Expr *, 8> PrivateCopies;
1912   for (const auto *C : S.getClausesOfKind<OMPPrivateClause>()) {
1913     auto IRef = C->varlist_begin();
1914     for (auto *IInit : C->private_copies()) {
1915       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
1916       if (EmittedAsPrivate.insert(OrigVD->getCanonicalDecl()).second) {
1917         PrivateVars.push_back(*IRef);
1918         PrivateCopies.push_back(IInit);
1919       }
1920       ++IRef;
1921     }
1922   }
1923   EmittedAsPrivate.clear();
1924   // Get list of firstprivate variables.
1925   llvm::SmallVector<const Expr *, 8> FirstprivateVars;
1926   llvm::SmallVector<const Expr *, 8> FirstprivateCopies;
1927   llvm::SmallVector<const Expr *, 8> FirstprivateInits;
1928   for (const auto *C : S.getClausesOfKind<OMPFirstprivateClause>()) {
1929     auto IRef = C->varlist_begin();
1930     auto IElemInitRef = C->inits().begin();
1931     for (auto *IInit : C->private_copies()) {
1932       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IRef)->getDecl());
1933       if (EmittedAsPrivate.insert(OrigVD->getCanonicalDecl()).second) {
1934         FirstprivateVars.push_back(*IRef);
1935         FirstprivateCopies.push_back(IInit);
1936         FirstprivateInits.push_back(*IElemInitRef);
1937       }
1938       ++IRef, ++IElemInitRef;
1939     }
1940   }
1941   // Build list of dependences.
1942   llvm::SmallVector<std::pair<OpenMPDependClauseKind, const Expr *>, 8>
1943       Dependences;
1944   for (const auto *C : S.getClausesOfKind<OMPDependClause>()) {
1945     for (auto *IRef : C->varlists()) {
1946       Dependences.push_back(std::make_pair(C->getDependencyKind(), IRef));
1947     }
1948   }
1949   auto &&CodeGen = [PartId, &S, &PrivateVars, &FirstprivateVars](
1950       CodeGenFunction &CGF) {
1951     // Set proper addresses for generated private copies.
1952     auto *CS = cast<CapturedStmt>(S.getAssociatedStmt());
1953     OMPPrivateScope Scope(CGF);
1954     if (!PrivateVars.empty() || !FirstprivateVars.empty()) {
1955       auto *CopyFn = CGF.Builder.CreateLoad(
1956           CGF.GetAddrOfLocalVar(CS->getCapturedDecl()->getParam(3)));
1957       auto *PrivatesPtr = CGF.Builder.CreateLoad(
1958           CGF.GetAddrOfLocalVar(CS->getCapturedDecl()->getParam(2)));
1959       // Map privates.
1960       llvm::SmallVector<std::pair<const VarDecl *, Address>, 16>
1961           PrivatePtrs;
1962       llvm::SmallVector<llvm::Value *, 16> CallArgs;
1963       CallArgs.push_back(PrivatesPtr);
1964       for (auto *E : PrivateVars) {
1965         auto *VD = cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl());
1966         Address PrivatePtr =
1967             CGF.CreateMemTemp(CGF.getContext().getPointerType(E->getType()));
1968         PrivatePtrs.push_back(std::make_pair(VD, PrivatePtr));
1969         CallArgs.push_back(PrivatePtr.getPointer());
1970       }
1971       for (auto *E : FirstprivateVars) {
1972         auto *VD = cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl());
1973         Address PrivatePtr =
1974             CGF.CreateMemTemp(CGF.getContext().getPointerType(E->getType()));
1975         PrivatePtrs.push_back(std::make_pair(VD, PrivatePtr));
1976         CallArgs.push_back(PrivatePtr.getPointer());
1977       }
1978       CGF.EmitRuntimeCall(CopyFn, CallArgs);
1979       for (auto &&Pair : PrivatePtrs) {
1980         Address Replacement(CGF.Builder.CreateLoad(Pair.second),
1981                             CGF.getContext().getDeclAlign(Pair.first));
1982         Scope.addPrivate(Pair.first, [Replacement]() { return Replacement; });
1983       }
1984     }
1985     (void)Scope.Privatize();
1986     if (*PartId) {
1987       // TODO: emit code for untied tasks.
1988     }
1989     CGF.EmitStmt(CS->getCapturedStmt());
1990   };
1991   auto OutlinedFn = CGM.getOpenMPRuntime().emitTaskOutlinedFunction(
1992       S, *I, OMPD_task, CodeGen);
1993   // Check if we should emit tied or untied task.
1994   bool Tied = !S.getSingleClause<OMPUntiedClause>();
1995   // Check if the task is final
1996   llvm::PointerIntPair<llvm::Value *, 1, bool> Final;
1997   if (const auto *Clause = S.getSingleClause<OMPFinalClause>()) {
1998     // If the condition constant folds and can be elided, try to avoid emitting
1999     // the condition and the dead arm of the if/else.
2000     auto *Cond = Clause->getCondition();
2001     bool CondConstant;
2002     if (ConstantFoldsToSimpleInteger(Cond, CondConstant))
2003       Final.setInt(CondConstant);
2004     else
2005       Final.setPointer(EvaluateExprAsBool(Cond));
2006   } else {
2007     // By default the task is not final.
2008     Final.setInt(/*IntVal=*/false);
2009   }
2010   auto SharedsTy = getContext().getRecordType(CS->getCapturedRecordDecl());
2011   const Expr *IfCond = nullptr;
2012   for (const auto *C : S.getClausesOfKind<OMPIfClause>()) {
2013     if (C->getNameModifier() == OMPD_unknown ||
2014         C->getNameModifier() == OMPD_task) {
2015       IfCond = C->getCondition();
2016       break;
2017     }
2018   }
2019   CGM.getOpenMPRuntime().emitTaskCall(
2020       *this, S.getLocStart(), S, Tied, Final, OutlinedFn, SharedsTy,
2021       CapturedStruct, IfCond, PrivateVars, PrivateCopies, FirstprivateVars,
2022       FirstprivateCopies, FirstprivateInits, Dependences);
2023 }
2024 
EmitOMPTaskyieldDirective(const OMPTaskyieldDirective & S)2025 void CodeGenFunction::EmitOMPTaskyieldDirective(
2026     const OMPTaskyieldDirective &S) {
2027   CGM.getOpenMPRuntime().emitTaskyieldCall(*this, S.getLocStart());
2028 }
2029 
EmitOMPBarrierDirective(const OMPBarrierDirective & S)2030 void CodeGenFunction::EmitOMPBarrierDirective(const OMPBarrierDirective &S) {
2031   CGM.getOpenMPRuntime().emitBarrierCall(*this, S.getLocStart(), OMPD_barrier);
2032 }
2033 
EmitOMPTaskwaitDirective(const OMPTaskwaitDirective & S)2034 void CodeGenFunction::EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S) {
2035   CGM.getOpenMPRuntime().emitTaskwaitCall(*this, S.getLocStart());
2036 }
2037 
EmitOMPTaskgroupDirective(const OMPTaskgroupDirective & S)2038 void CodeGenFunction::EmitOMPTaskgroupDirective(
2039     const OMPTaskgroupDirective &S) {
2040   LexicalScope Scope(*this, S.getSourceRange());
2041   auto &&CodeGen = [&S](CodeGenFunction &CGF) {
2042     CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
2043   };
2044   CGM.getOpenMPRuntime().emitTaskgroupRegion(*this, CodeGen, S.getLocStart());
2045 }
2046 
EmitOMPFlushDirective(const OMPFlushDirective & S)2047 void CodeGenFunction::EmitOMPFlushDirective(const OMPFlushDirective &S) {
2048   CGM.getOpenMPRuntime().emitFlush(*this, [&]() -> ArrayRef<const Expr *> {
2049     if (const auto *FlushClause = S.getSingleClause<OMPFlushClause>()) {
2050       return llvm::makeArrayRef(FlushClause->varlist_begin(),
2051                                 FlushClause->varlist_end());
2052     }
2053     return llvm::None;
2054   }(), S.getLocStart());
2055 }
2056 
EmitOMPDistributeDirective(const OMPDistributeDirective & S)2057 void CodeGenFunction::EmitOMPDistributeDirective(
2058     const OMPDistributeDirective &S) {
2059   llvm_unreachable("CodeGen for 'omp distribute' is not supported yet.");
2060 }
2061 
emitOutlinedOrderedFunction(CodeGenModule & CGM,const CapturedStmt * S)2062 static llvm::Function *emitOutlinedOrderedFunction(CodeGenModule &CGM,
2063                                                    const CapturedStmt *S) {
2064   CodeGenFunction CGF(CGM, /*suppressNewContext=*/true);
2065   CodeGenFunction::CGCapturedStmtInfo CapStmtInfo;
2066   CGF.CapturedStmtInfo = &CapStmtInfo;
2067   auto *Fn = CGF.GenerateOpenMPCapturedStmtFunction(*S);
2068   Fn->addFnAttr(llvm::Attribute::NoInline);
2069   return Fn;
2070 }
2071 
EmitOMPOrderedDirective(const OMPOrderedDirective & S)2072 void CodeGenFunction::EmitOMPOrderedDirective(const OMPOrderedDirective &S) {
2073   if (!S.getAssociatedStmt())
2074     return;
2075   LexicalScope Scope(*this, S.getSourceRange());
2076   auto *C = S.getSingleClause<OMPSIMDClause>();
2077   auto &&CodeGen = [&S, C, this](CodeGenFunction &CGF) {
2078     if (C) {
2079       auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
2080       llvm::SmallVector<llvm::Value *, 16> CapturedVars;
2081       CGF.GenerateOpenMPCapturedVars(*CS, CapturedVars);
2082       auto *OutlinedFn = emitOutlinedOrderedFunction(CGM, CS);
2083       CGF.EmitNounwindRuntimeCall(OutlinedFn, CapturedVars);
2084     } else {
2085       CGF.EmitStmt(
2086           cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
2087     }
2088   };
2089   CGM.getOpenMPRuntime().emitOrderedRegion(*this, CodeGen, S.getLocStart(), !C);
2090 }
2091 
convertToScalarValue(CodeGenFunction & CGF,RValue Val,QualType SrcType,QualType DestType,SourceLocation Loc)2092 static llvm::Value *convertToScalarValue(CodeGenFunction &CGF, RValue Val,
2093                                          QualType SrcType, QualType DestType,
2094                                          SourceLocation Loc) {
2095   assert(CGF.hasScalarEvaluationKind(DestType) &&
2096          "DestType must have scalar evaluation kind.");
2097   assert(!Val.isAggregate() && "Must be a scalar or complex.");
2098   return Val.isScalar()
2099              ? CGF.EmitScalarConversion(Val.getScalarVal(), SrcType, DestType,
2100                                         Loc)
2101              : CGF.EmitComplexToScalarConversion(Val.getComplexVal(), SrcType,
2102                                                  DestType, Loc);
2103 }
2104 
2105 static CodeGenFunction::ComplexPairTy
convertToComplexValue(CodeGenFunction & CGF,RValue Val,QualType SrcType,QualType DestType,SourceLocation Loc)2106 convertToComplexValue(CodeGenFunction &CGF, RValue Val, QualType SrcType,
2107                       QualType DestType, SourceLocation Loc) {
2108   assert(CGF.getEvaluationKind(DestType) == TEK_Complex &&
2109          "DestType must have complex evaluation kind.");
2110   CodeGenFunction::ComplexPairTy ComplexVal;
2111   if (Val.isScalar()) {
2112     // Convert the input element to the element type of the complex.
2113     auto DestElementType = DestType->castAs<ComplexType>()->getElementType();
2114     auto ScalarVal = CGF.EmitScalarConversion(Val.getScalarVal(), SrcType,
2115                                               DestElementType, Loc);
2116     ComplexVal = CodeGenFunction::ComplexPairTy(
2117         ScalarVal, llvm::Constant::getNullValue(ScalarVal->getType()));
2118   } else {
2119     assert(Val.isComplex() && "Must be a scalar or complex.");
2120     auto SrcElementType = SrcType->castAs<ComplexType>()->getElementType();
2121     auto DestElementType = DestType->castAs<ComplexType>()->getElementType();
2122     ComplexVal.first = CGF.EmitScalarConversion(
2123         Val.getComplexVal().first, SrcElementType, DestElementType, Loc);
2124     ComplexVal.second = CGF.EmitScalarConversion(
2125         Val.getComplexVal().second, SrcElementType, DestElementType, Loc);
2126   }
2127   return ComplexVal;
2128 }
2129 
emitSimpleAtomicStore(CodeGenFunction & CGF,bool IsSeqCst,LValue LVal,RValue RVal)2130 static void emitSimpleAtomicStore(CodeGenFunction &CGF, bool IsSeqCst,
2131                                   LValue LVal, RValue RVal) {
2132   if (LVal.isGlobalReg()) {
2133     CGF.EmitStoreThroughGlobalRegLValue(RVal, LVal);
2134   } else {
2135     CGF.EmitAtomicStore(RVal, LVal, IsSeqCst ? llvm::SequentiallyConsistent
2136                                              : llvm::Monotonic,
2137                         LVal.isVolatile(), /*IsInit=*/false);
2138   }
2139 }
2140 
emitSimpleStore(CodeGenFunction & CGF,LValue LVal,RValue RVal,QualType RValTy,SourceLocation Loc)2141 static void emitSimpleStore(CodeGenFunction &CGF, LValue LVal, RValue RVal,
2142                             QualType RValTy, SourceLocation Loc) {
2143   switch (CGF.getEvaluationKind(LVal.getType())) {
2144   case TEK_Scalar:
2145     CGF.EmitStoreThroughLValue(RValue::get(convertToScalarValue(
2146                                    CGF, RVal, RValTy, LVal.getType(), Loc)),
2147                                LVal);
2148     break;
2149   case TEK_Complex:
2150     CGF.EmitStoreOfComplex(
2151         convertToComplexValue(CGF, RVal, RValTy, LVal.getType(), Loc), LVal,
2152         /*isInit=*/false);
2153     break;
2154   case TEK_Aggregate:
2155     llvm_unreachable("Must be a scalar or complex.");
2156   }
2157 }
2158 
EmitOMPAtomicReadExpr(CodeGenFunction & CGF,bool IsSeqCst,const Expr * X,const Expr * V,SourceLocation Loc)2159 static void EmitOMPAtomicReadExpr(CodeGenFunction &CGF, bool IsSeqCst,
2160                                   const Expr *X, const Expr *V,
2161                                   SourceLocation Loc) {
2162   // v = x;
2163   assert(V->isLValue() && "V of 'omp atomic read' is not lvalue");
2164   assert(X->isLValue() && "X of 'omp atomic read' is not lvalue");
2165   LValue XLValue = CGF.EmitLValue(X);
2166   LValue VLValue = CGF.EmitLValue(V);
2167   RValue Res = XLValue.isGlobalReg()
2168                    ? CGF.EmitLoadOfLValue(XLValue, Loc)
2169                    : CGF.EmitAtomicLoad(XLValue, Loc,
2170                                         IsSeqCst ? llvm::SequentiallyConsistent
2171                                                  : llvm::Monotonic,
2172                                         XLValue.isVolatile());
2173   // OpenMP, 2.12.6, atomic Construct
2174   // Any atomic construct with a seq_cst clause forces the atomically
2175   // performed operation to include an implicit flush operation without a
2176   // list.
2177   if (IsSeqCst)
2178     CGF.CGM.getOpenMPRuntime().emitFlush(CGF, llvm::None, Loc);
2179   emitSimpleStore(CGF, VLValue, Res, X->getType().getNonReferenceType(), Loc);
2180 }
2181 
EmitOMPAtomicWriteExpr(CodeGenFunction & CGF,bool IsSeqCst,const Expr * X,const Expr * E,SourceLocation Loc)2182 static void EmitOMPAtomicWriteExpr(CodeGenFunction &CGF, bool IsSeqCst,
2183                                    const Expr *X, const Expr *E,
2184                                    SourceLocation Loc) {
2185   // x = expr;
2186   assert(X->isLValue() && "X of 'omp atomic write' is not lvalue");
2187   emitSimpleAtomicStore(CGF, IsSeqCst, CGF.EmitLValue(X), CGF.EmitAnyExpr(E));
2188   // OpenMP, 2.12.6, atomic Construct
2189   // Any atomic construct with a seq_cst clause forces the atomically
2190   // performed operation to include an implicit flush operation without a
2191   // list.
2192   if (IsSeqCst)
2193     CGF.CGM.getOpenMPRuntime().emitFlush(CGF, llvm::None, Loc);
2194 }
2195 
emitOMPAtomicRMW(CodeGenFunction & CGF,LValue X,RValue Update,BinaryOperatorKind BO,llvm::AtomicOrdering AO,bool IsXLHSInRHSPart)2196 static std::pair<bool, RValue> emitOMPAtomicRMW(CodeGenFunction &CGF, LValue X,
2197                                                 RValue Update,
2198                                                 BinaryOperatorKind BO,
2199                                                 llvm::AtomicOrdering AO,
2200                                                 bool IsXLHSInRHSPart) {
2201   auto &Context = CGF.CGM.getContext();
2202   // Allow atomicrmw only if 'x' and 'update' are integer values, lvalue for 'x'
2203   // expression is simple and atomic is allowed for the given type for the
2204   // target platform.
2205   if (BO == BO_Comma || !Update.isScalar() ||
2206       !Update.getScalarVal()->getType()->isIntegerTy() ||
2207       !X.isSimple() || (!isa<llvm::ConstantInt>(Update.getScalarVal()) &&
2208                         (Update.getScalarVal()->getType() !=
2209                          X.getAddress().getElementType())) ||
2210       !X.getAddress().getElementType()->isIntegerTy() ||
2211       !Context.getTargetInfo().hasBuiltinAtomic(
2212           Context.getTypeSize(X.getType()), Context.toBits(X.getAlignment())))
2213     return std::make_pair(false, RValue::get(nullptr));
2214 
2215   llvm::AtomicRMWInst::BinOp RMWOp;
2216   switch (BO) {
2217   case BO_Add:
2218     RMWOp = llvm::AtomicRMWInst::Add;
2219     break;
2220   case BO_Sub:
2221     if (!IsXLHSInRHSPart)
2222       return std::make_pair(false, RValue::get(nullptr));
2223     RMWOp = llvm::AtomicRMWInst::Sub;
2224     break;
2225   case BO_And:
2226     RMWOp = llvm::AtomicRMWInst::And;
2227     break;
2228   case BO_Or:
2229     RMWOp = llvm::AtomicRMWInst::Or;
2230     break;
2231   case BO_Xor:
2232     RMWOp = llvm::AtomicRMWInst::Xor;
2233     break;
2234   case BO_LT:
2235     RMWOp = X.getType()->hasSignedIntegerRepresentation()
2236                 ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Min
2237                                    : llvm::AtomicRMWInst::Max)
2238                 : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMin
2239                                    : llvm::AtomicRMWInst::UMax);
2240     break;
2241   case BO_GT:
2242     RMWOp = X.getType()->hasSignedIntegerRepresentation()
2243                 ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Max
2244                                    : llvm::AtomicRMWInst::Min)
2245                 : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMax
2246                                    : llvm::AtomicRMWInst::UMin);
2247     break;
2248   case BO_Assign:
2249     RMWOp = llvm::AtomicRMWInst::Xchg;
2250     break;
2251   case BO_Mul:
2252   case BO_Div:
2253   case BO_Rem:
2254   case BO_Shl:
2255   case BO_Shr:
2256   case BO_LAnd:
2257   case BO_LOr:
2258     return std::make_pair(false, RValue::get(nullptr));
2259   case BO_PtrMemD:
2260   case BO_PtrMemI:
2261   case BO_LE:
2262   case BO_GE:
2263   case BO_EQ:
2264   case BO_NE:
2265   case BO_AddAssign:
2266   case BO_SubAssign:
2267   case BO_AndAssign:
2268   case BO_OrAssign:
2269   case BO_XorAssign:
2270   case BO_MulAssign:
2271   case BO_DivAssign:
2272   case BO_RemAssign:
2273   case BO_ShlAssign:
2274   case BO_ShrAssign:
2275   case BO_Comma:
2276     llvm_unreachable("Unsupported atomic update operation");
2277   }
2278   auto *UpdateVal = Update.getScalarVal();
2279   if (auto *IC = dyn_cast<llvm::ConstantInt>(UpdateVal)) {
2280     UpdateVal = CGF.Builder.CreateIntCast(
2281         IC, X.getAddress().getElementType(),
2282         X.getType()->hasSignedIntegerRepresentation());
2283   }
2284   auto *Res = CGF.Builder.CreateAtomicRMW(RMWOp, X.getPointer(), UpdateVal, AO);
2285   return std::make_pair(true, RValue::get(Res));
2286 }
2287 
EmitOMPAtomicSimpleUpdateExpr(LValue X,RValue E,BinaryOperatorKind BO,bool IsXLHSInRHSPart,llvm::AtomicOrdering AO,SourceLocation Loc,const llvm::function_ref<RValue (RValue)> & CommonGen)2288 std::pair<bool, RValue> CodeGenFunction::EmitOMPAtomicSimpleUpdateExpr(
2289     LValue X, RValue E, BinaryOperatorKind BO, bool IsXLHSInRHSPart,
2290     llvm::AtomicOrdering AO, SourceLocation Loc,
2291     const llvm::function_ref<RValue(RValue)> &CommonGen) {
2292   // Update expressions are allowed to have the following forms:
2293   // x binop= expr; -> xrval + expr;
2294   // x++, ++x -> xrval + 1;
2295   // x--, --x -> xrval - 1;
2296   // x = x binop expr; -> xrval binop expr
2297   // x = expr Op x; - > expr binop xrval;
2298   auto Res = emitOMPAtomicRMW(*this, X, E, BO, AO, IsXLHSInRHSPart);
2299   if (!Res.first) {
2300     if (X.isGlobalReg()) {
2301       // Emit an update expression: 'xrval' binop 'expr' or 'expr' binop
2302       // 'xrval'.
2303       EmitStoreThroughLValue(CommonGen(EmitLoadOfLValue(X, Loc)), X);
2304     } else {
2305       // Perform compare-and-swap procedure.
2306       EmitAtomicUpdate(X, AO, CommonGen, X.getType().isVolatileQualified());
2307     }
2308   }
2309   return Res;
2310 }
2311 
EmitOMPAtomicUpdateExpr(CodeGenFunction & CGF,bool IsSeqCst,const Expr * X,const Expr * E,const Expr * UE,bool IsXLHSInRHSPart,SourceLocation Loc)2312 static void EmitOMPAtomicUpdateExpr(CodeGenFunction &CGF, bool IsSeqCst,
2313                                     const Expr *X, const Expr *E,
2314                                     const Expr *UE, bool IsXLHSInRHSPart,
2315                                     SourceLocation Loc) {
2316   assert(isa<BinaryOperator>(UE->IgnoreImpCasts()) &&
2317          "Update expr in 'atomic update' must be a binary operator.");
2318   auto *BOUE = cast<BinaryOperator>(UE->IgnoreImpCasts());
2319   // Update expressions are allowed to have the following forms:
2320   // x binop= expr; -> xrval + expr;
2321   // x++, ++x -> xrval + 1;
2322   // x--, --x -> xrval - 1;
2323   // x = x binop expr; -> xrval binop expr
2324   // x = expr Op x; - > expr binop xrval;
2325   assert(X->isLValue() && "X of 'omp atomic update' is not lvalue");
2326   LValue XLValue = CGF.EmitLValue(X);
2327   RValue ExprRValue = CGF.EmitAnyExpr(E);
2328   auto AO = IsSeqCst ? llvm::SequentiallyConsistent : llvm::Monotonic;
2329   auto *LHS = cast<OpaqueValueExpr>(BOUE->getLHS()->IgnoreImpCasts());
2330   auto *RHS = cast<OpaqueValueExpr>(BOUE->getRHS()->IgnoreImpCasts());
2331   auto *XRValExpr = IsXLHSInRHSPart ? LHS : RHS;
2332   auto *ERValExpr = IsXLHSInRHSPart ? RHS : LHS;
2333   auto Gen =
2334       [&CGF, UE, ExprRValue, XRValExpr, ERValExpr](RValue XRValue) -> RValue {
2335         CodeGenFunction::OpaqueValueMapping MapExpr(CGF, ERValExpr, ExprRValue);
2336         CodeGenFunction::OpaqueValueMapping MapX(CGF, XRValExpr, XRValue);
2337         return CGF.EmitAnyExpr(UE);
2338       };
2339   (void)CGF.EmitOMPAtomicSimpleUpdateExpr(
2340       XLValue, ExprRValue, BOUE->getOpcode(), IsXLHSInRHSPart, AO, Loc, Gen);
2341   // OpenMP, 2.12.6, atomic Construct
2342   // Any atomic construct with a seq_cst clause forces the atomically
2343   // performed operation to include an implicit flush operation without a
2344   // list.
2345   if (IsSeqCst)
2346     CGF.CGM.getOpenMPRuntime().emitFlush(CGF, llvm::None, Loc);
2347 }
2348 
convertToType(CodeGenFunction & CGF,RValue Value,QualType SourceType,QualType ResType,SourceLocation Loc)2349 static RValue convertToType(CodeGenFunction &CGF, RValue Value,
2350                             QualType SourceType, QualType ResType,
2351                             SourceLocation Loc) {
2352   switch (CGF.getEvaluationKind(ResType)) {
2353   case TEK_Scalar:
2354     return RValue::get(
2355         convertToScalarValue(CGF, Value, SourceType, ResType, Loc));
2356   case TEK_Complex: {
2357     auto Res = convertToComplexValue(CGF, Value, SourceType, ResType, Loc);
2358     return RValue::getComplex(Res.first, Res.second);
2359   }
2360   case TEK_Aggregate:
2361     break;
2362   }
2363   llvm_unreachable("Must be a scalar or complex.");
2364 }
2365 
EmitOMPAtomicCaptureExpr(CodeGenFunction & CGF,bool IsSeqCst,bool IsPostfixUpdate,const Expr * V,const Expr * X,const Expr * E,const Expr * UE,bool IsXLHSInRHSPart,SourceLocation Loc)2366 static void EmitOMPAtomicCaptureExpr(CodeGenFunction &CGF, bool IsSeqCst,
2367                                      bool IsPostfixUpdate, const Expr *V,
2368                                      const Expr *X, const Expr *E,
2369                                      const Expr *UE, bool IsXLHSInRHSPart,
2370                                      SourceLocation Loc) {
2371   assert(X->isLValue() && "X of 'omp atomic capture' is not lvalue");
2372   assert(V->isLValue() && "V of 'omp atomic capture' is not lvalue");
2373   RValue NewVVal;
2374   LValue VLValue = CGF.EmitLValue(V);
2375   LValue XLValue = CGF.EmitLValue(X);
2376   RValue ExprRValue = CGF.EmitAnyExpr(E);
2377   auto AO = IsSeqCst ? llvm::SequentiallyConsistent : llvm::Monotonic;
2378   QualType NewVValType;
2379   if (UE) {
2380     // 'x' is updated with some additional value.
2381     assert(isa<BinaryOperator>(UE->IgnoreImpCasts()) &&
2382            "Update expr in 'atomic capture' must be a binary operator.");
2383     auto *BOUE = cast<BinaryOperator>(UE->IgnoreImpCasts());
2384     // Update expressions are allowed to have the following forms:
2385     // x binop= expr; -> xrval + expr;
2386     // x++, ++x -> xrval + 1;
2387     // x--, --x -> xrval - 1;
2388     // x = x binop expr; -> xrval binop expr
2389     // x = expr Op x; - > expr binop xrval;
2390     auto *LHS = cast<OpaqueValueExpr>(BOUE->getLHS()->IgnoreImpCasts());
2391     auto *RHS = cast<OpaqueValueExpr>(BOUE->getRHS()->IgnoreImpCasts());
2392     auto *XRValExpr = IsXLHSInRHSPart ? LHS : RHS;
2393     NewVValType = XRValExpr->getType();
2394     auto *ERValExpr = IsXLHSInRHSPart ? RHS : LHS;
2395     auto &&Gen = [&CGF, &NewVVal, UE, ExprRValue, XRValExpr, ERValExpr,
2396                   IsSeqCst, IsPostfixUpdate](RValue XRValue) -> RValue {
2397       CodeGenFunction::OpaqueValueMapping MapExpr(CGF, ERValExpr, ExprRValue);
2398       CodeGenFunction::OpaqueValueMapping MapX(CGF, XRValExpr, XRValue);
2399       RValue Res = CGF.EmitAnyExpr(UE);
2400       NewVVal = IsPostfixUpdate ? XRValue : Res;
2401       return Res;
2402     };
2403     auto Res = CGF.EmitOMPAtomicSimpleUpdateExpr(
2404         XLValue, ExprRValue, BOUE->getOpcode(), IsXLHSInRHSPart, AO, Loc, Gen);
2405     if (Res.first) {
2406       // 'atomicrmw' instruction was generated.
2407       if (IsPostfixUpdate) {
2408         // Use old value from 'atomicrmw'.
2409         NewVVal = Res.second;
2410       } else {
2411         // 'atomicrmw' does not provide new value, so evaluate it using old
2412         // value of 'x'.
2413         CodeGenFunction::OpaqueValueMapping MapExpr(CGF, ERValExpr, ExprRValue);
2414         CodeGenFunction::OpaqueValueMapping MapX(CGF, XRValExpr, Res.second);
2415         NewVVal = CGF.EmitAnyExpr(UE);
2416       }
2417     }
2418   } else {
2419     // 'x' is simply rewritten with some 'expr'.
2420     NewVValType = X->getType().getNonReferenceType();
2421     ExprRValue = convertToType(CGF, ExprRValue, E->getType(),
2422                                X->getType().getNonReferenceType(), Loc);
2423     auto &&Gen = [&CGF, &NewVVal, ExprRValue](RValue XRValue) -> RValue {
2424       NewVVal = XRValue;
2425       return ExprRValue;
2426     };
2427     // Try to perform atomicrmw xchg, otherwise simple exchange.
2428     auto Res = CGF.EmitOMPAtomicSimpleUpdateExpr(
2429         XLValue, ExprRValue, /*BO=*/BO_Assign, /*IsXLHSInRHSPart=*/false, AO,
2430         Loc, Gen);
2431     if (Res.first) {
2432       // 'atomicrmw' instruction was generated.
2433       NewVVal = IsPostfixUpdate ? Res.second : ExprRValue;
2434     }
2435   }
2436   // Emit post-update store to 'v' of old/new 'x' value.
2437   emitSimpleStore(CGF, VLValue, NewVVal, NewVValType, Loc);
2438   // OpenMP, 2.12.6, atomic Construct
2439   // Any atomic construct with a seq_cst clause forces the atomically
2440   // performed operation to include an implicit flush operation without a
2441   // list.
2442   if (IsSeqCst)
2443     CGF.CGM.getOpenMPRuntime().emitFlush(CGF, llvm::None, Loc);
2444 }
2445 
EmitOMPAtomicExpr(CodeGenFunction & CGF,OpenMPClauseKind Kind,bool IsSeqCst,bool IsPostfixUpdate,const Expr * X,const Expr * V,const Expr * E,const Expr * UE,bool IsXLHSInRHSPart,SourceLocation Loc)2446 static void EmitOMPAtomicExpr(CodeGenFunction &CGF, OpenMPClauseKind Kind,
2447                               bool IsSeqCst, bool IsPostfixUpdate,
2448                               const Expr *X, const Expr *V, const Expr *E,
2449                               const Expr *UE, bool IsXLHSInRHSPart,
2450                               SourceLocation Loc) {
2451   switch (Kind) {
2452   case OMPC_read:
2453     EmitOMPAtomicReadExpr(CGF, IsSeqCst, X, V, Loc);
2454     break;
2455   case OMPC_write:
2456     EmitOMPAtomicWriteExpr(CGF, IsSeqCst, X, E, Loc);
2457     break;
2458   case OMPC_unknown:
2459   case OMPC_update:
2460     EmitOMPAtomicUpdateExpr(CGF, IsSeqCst, X, E, UE, IsXLHSInRHSPart, Loc);
2461     break;
2462   case OMPC_capture:
2463     EmitOMPAtomicCaptureExpr(CGF, IsSeqCst, IsPostfixUpdate, V, X, E, UE,
2464                              IsXLHSInRHSPart, Loc);
2465     break;
2466   case OMPC_if:
2467   case OMPC_final:
2468   case OMPC_num_threads:
2469   case OMPC_private:
2470   case OMPC_firstprivate:
2471   case OMPC_lastprivate:
2472   case OMPC_reduction:
2473   case OMPC_safelen:
2474   case OMPC_simdlen:
2475   case OMPC_collapse:
2476   case OMPC_default:
2477   case OMPC_seq_cst:
2478   case OMPC_shared:
2479   case OMPC_linear:
2480   case OMPC_aligned:
2481   case OMPC_copyin:
2482   case OMPC_copyprivate:
2483   case OMPC_flush:
2484   case OMPC_proc_bind:
2485   case OMPC_schedule:
2486   case OMPC_ordered:
2487   case OMPC_nowait:
2488   case OMPC_untied:
2489   case OMPC_threadprivate:
2490   case OMPC_depend:
2491   case OMPC_mergeable:
2492   case OMPC_device:
2493   case OMPC_threads:
2494   case OMPC_simd:
2495   case OMPC_map:
2496   case OMPC_num_teams:
2497   case OMPC_thread_limit:
2498   case OMPC_priority:
2499   case OMPC_grainsize:
2500   case OMPC_nogroup:
2501   case OMPC_num_tasks:
2502   case OMPC_hint:
2503     llvm_unreachable("Clause is not allowed in 'omp atomic'.");
2504   }
2505 }
2506 
EmitOMPAtomicDirective(const OMPAtomicDirective & S)2507 void CodeGenFunction::EmitOMPAtomicDirective(const OMPAtomicDirective &S) {
2508   bool IsSeqCst = S.getSingleClause<OMPSeqCstClause>();
2509   OpenMPClauseKind Kind = OMPC_unknown;
2510   for (auto *C : S.clauses()) {
2511     // Find first clause (skip seq_cst clause, if it is first).
2512     if (C->getClauseKind() != OMPC_seq_cst) {
2513       Kind = C->getClauseKind();
2514       break;
2515     }
2516   }
2517 
2518   const auto *CS =
2519       S.getAssociatedStmt()->IgnoreContainers(/*IgnoreCaptured=*/true);
2520   if (const auto *EWC = dyn_cast<ExprWithCleanups>(CS)) {
2521     enterFullExpression(EWC);
2522   }
2523   // Processing for statements under 'atomic capture'.
2524   if (const auto *Compound = dyn_cast<CompoundStmt>(CS)) {
2525     for (const auto *C : Compound->body()) {
2526       if (const auto *EWC = dyn_cast<ExprWithCleanups>(C)) {
2527         enterFullExpression(EWC);
2528       }
2529     }
2530   }
2531 
2532   LexicalScope Scope(*this, S.getSourceRange());
2533   auto &&CodeGen = [&S, Kind, IsSeqCst, CS](CodeGenFunction &CGF) {
2534     CGF.EmitStopPoint(CS);
2535     EmitOMPAtomicExpr(CGF, Kind, IsSeqCst, S.isPostfixUpdate(), S.getX(),
2536                       S.getV(), S.getExpr(), S.getUpdateExpr(),
2537                       S.isXLHSInRHSPart(), S.getLocStart());
2538   };
2539   CGM.getOpenMPRuntime().emitInlinedDirective(*this, OMPD_atomic, CodeGen);
2540 }
2541 
EmitOMPTargetDirective(const OMPTargetDirective & S)2542 void CodeGenFunction::EmitOMPTargetDirective(const OMPTargetDirective &S) {
2543   LexicalScope Scope(*this, S.getSourceRange());
2544   const CapturedStmt &CS = *cast<CapturedStmt>(S.getAssociatedStmt());
2545 
2546   llvm::SmallVector<llvm::Value *, 16> CapturedVars;
2547   GenerateOpenMPCapturedVars(CS, CapturedVars);
2548 
2549   // Emit target region as a standalone region.
2550   auto &&CodeGen = [&CS](CodeGenFunction &CGF) {
2551     CGF.EmitStmt(CS.getCapturedStmt());
2552   };
2553 
2554   // Obtain the target region outlined function.
2555   llvm::Value *Fn =
2556       CGM.getOpenMPRuntime().emitTargetOutlinedFunction(S, CodeGen);
2557 
2558   // Check if we have any if clause associated with the directive.
2559   const Expr *IfCond = nullptr;
2560 
2561   if (auto *C = S.getSingleClause<OMPIfClause>()) {
2562     IfCond = C->getCondition();
2563   }
2564 
2565   // Check if we have any device clause associated with the directive.
2566   const Expr *Device = nullptr;
2567   if (auto *C = S.getSingleClause<OMPDeviceClause>()) {
2568     Device = C->getDevice();
2569   }
2570 
2571   CGM.getOpenMPRuntime().emitTargetCall(*this, S, Fn, IfCond, Device,
2572                                         CapturedVars);
2573 }
2574 
EmitOMPTeamsDirective(const OMPTeamsDirective &)2575 void CodeGenFunction::EmitOMPTeamsDirective(const OMPTeamsDirective &) {
2576   llvm_unreachable("CodeGen for 'omp teams' is not supported yet.");
2577 }
2578 
EmitOMPCancellationPointDirective(const OMPCancellationPointDirective & S)2579 void CodeGenFunction::EmitOMPCancellationPointDirective(
2580     const OMPCancellationPointDirective &S) {
2581   CGM.getOpenMPRuntime().emitCancellationPointCall(*this, S.getLocStart(),
2582                                                    S.getCancelRegion());
2583 }
2584 
EmitOMPCancelDirective(const OMPCancelDirective & S)2585 void CodeGenFunction::EmitOMPCancelDirective(const OMPCancelDirective &S) {
2586   const Expr *IfCond = nullptr;
2587   for (const auto *C : S.getClausesOfKind<OMPIfClause>()) {
2588     if (C->getNameModifier() == OMPD_unknown ||
2589         C->getNameModifier() == OMPD_cancel) {
2590       IfCond = C->getCondition();
2591       break;
2592     }
2593   }
2594   CGM.getOpenMPRuntime().emitCancelCall(*this, S.getLocStart(), IfCond,
2595                                         S.getCancelRegion());
2596 }
2597 
2598 CodeGenFunction::JumpDest
getOMPCancelDestination(OpenMPDirectiveKind Kind)2599 CodeGenFunction::getOMPCancelDestination(OpenMPDirectiveKind Kind) {
2600   if (Kind == OMPD_parallel || Kind == OMPD_task)
2601     return ReturnBlock;
2602   assert(Kind == OMPD_for || Kind == OMPD_section || Kind == OMPD_sections ||
2603          Kind == OMPD_parallel_sections || Kind == OMPD_parallel_for);
2604   return BreakContinueStack.back().BreakBlock;
2605 }
2606 
2607 // Generate the instructions for '#pragma omp target data' directive.
EmitOMPTargetDataDirective(const OMPTargetDataDirective & S)2608 void CodeGenFunction::EmitOMPTargetDataDirective(
2609     const OMPTargetDataDirective &S) {
2610   // emit the code inside the construct for now
2611   auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
2612   CGM.getOpenMPRuntime().emitInlinedDirective(
2613       *this, OMPD_target_data,
2614       [&CS](CodeGenFunction &CGF) { CGF.EmitStmt(CS->getCapturedStmt()); });
2615 }
2616 
EmitOMPTaskLoopDirective(const OMPTaskLoopDirective & S)2617 void CodeGenFunction::EmitOMPTaskLoopDirective(const OMPTaskLoopDirective &S) {
2618   // emit the code inside the construct for now
2619   auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
2620   CGM.getOpenMPRuntime().emitInlinedDirective(
2621       *this, OMPD_taskloop,
2622       [&CS](CodeGenFunction &CGF) { CGF.EmitStmt(CS->getCapturedStmt()); });
2623 }
2624 
EmitOMPTaskLoopSimdDirective(const OMPTaskLoopSimdDirective & S)2625 void CodeGenFunction::EmitOMPTaskLoopSimdDirective(
2626     const OMPTaskLoopSimdDirective &S) {
2627   // emit the code inside the construct for now
2628   auto CS = cast<CapturedStmt>(S.getAssociatedStmt());
2629   CGM.getOpenMPRuntime().emitInlinedDirective(
2630       *this, OMPD_taskloop_simd,
2631       [&CS](CodeGenFunction &CGF) { CGF.EmitStmt(CS->getCapturedStmt()); });
2632 }
2633 
2634