diff options
Diffstat (limited to 'clang/lib/Sema/SemaOpenMP.cpp')
| -rw-r--r-- | clang/lib/Sema/SemaOpenMP.cpp | 105 |
1 files changed, 104 insertions, 1 deletions
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp index 3972ff1079e..a458969c7e2 100644 --- a/clang/lib/Sema/SemaOpenMP.cpp +++ b/clang/lib/Sema/SemaOpenMP.cpp @@ -222,6 +222,8 @@ public: return Stack[Stack.size() - 2].Directive; return OMPD_unknown; } + /// \brief Return the directive associated with the provided scope. + OpenMPDirectiveKind getDirectiveForScope(const Scope *S) const; /// \brief Set default data sharing attribute to none. void setDefaultDSANone(SourceLocation Loc) { @@ -729,12 +731,107 @@ bool DSAStackTy::hasDirective(NamedDirectivesPredicate DPred, bool FromParent) { return false; } +OpenMPDirectiveKind DSAStackTy::getDirectiveForScope(const Scope *S) const { + for (auto I = Stack.rbegin(), EE = Stack.rend(); I != EE; ++I) + if (I->CurScope == S) + return I->Directive; + return OMPD_unknown; +} + void Sema::InitDataSharingAttributesStack() { VarDataSharingAttributesStack = new DSAStackTy(*this); } #define DSAStack static_cast<DSAStackTy *>(VarDataSharingAttributesStack) +bool Sema::IsOpenMPCapturedByRef(VarDecl *VD, + const CapturedRegionScopeInfo *RSI) { + assert(LangOpts.OpenMP && "OpenMP is not allowed"); + + auto &Ctx = getASTContext(); + bool IsByRef = true; + + // Find the directive that is associated with the provided scope. + auto DKind = DSAStack->getDirectiveForScope(RSI->TheScope); + auto Ty = VD->getType(); + + if (isOpenMPTargetDirective(DKind)) { + // This table summarizes how a given variable should be passed to the device + // given its type and the clauses where it appears. This table is based on + // the description in OpenMP 4.5 [2.10.4, target Construct] and + // OpenMP 4.5 [2.15.5, Data-mapping Attribute Rules and Clauses]. + // + // ========================================================================= + // | type | defaultmap | pvt | first | is_device_ptr | map | res. | + // | |(tofrom:scalar)| | pvt | | | | + // ========================================================================= + // | scl | | | | - | | bycopy| + // | scl | | - | x | - | - | bycopy| + // | scl | | x | - | - | - | null | + // | scl | x | | | - | | byref | + // | scl | x | - | x | - | - | bycopy| + // | scl | x | x | - | - | - | null | + // | scl | | - | - | - | x | byref | + // | scl | x | - | - | - | x | byref | + // + // | agg | n.a. | | | - | | byref | + // | agg | n.a. | - | x | - | - | byref | + // | agg | n.a. | x | - | - | - | null | + // | agg | n.a. | - | - | - | x | byref | + // | agg | n.a. | - | - | - | x[] | byref | + // + // | ptr | n.a. | | | - | | bycopy| + // | ptr | n.a. | - | x | - | - | bycopy| + // | ptr | n.a. | x | - | - | - | null | + // | ptr | n.a. | - | - | - | x | byref | + // | ptr | n.a. | - | - | - | x[] | bycopy| + // | ptr | n.a. | - | - | x | | bycopy| + // | ptr | n.a. | - | - | x | x | bycopy| + // | ptr | n.a. | - | - | x | x[] | bycopy| + // ========================================================================= + // Legend: + // scl - scalar + // ptr - pointer + // agg - aggregate + // x - applies + // - - invalid in this combination + // [] - mapped with an array section + // byref - should be mapped by reference + // byval - should be mapped by value + // null - initialize a local variable to null on the device + // + // Observations: + // - All scalar declarations that show up in a map clause have to be passed + // by reference, because they may have been mapped in the enclosing data + // environment. + // - If the scalar value does not fit the size of uintptr, it has to be + // passed by reference, regardless the result in the table above. + // - For pointers mapped by value that have either an implicit map or an + // array section, the runtime library may pass the NULL value to the + // device instead of the value passed to it by the compiler. + + // FIXME: Right now, only implicit maps are implemented. Properly mapping + // values requires having the map, private, and firstprivate clauses SEMA + // and parsing in place, which we don't yet. + + if (Ty->isReferenceType()) + Ty = Ty->castAs<ReferenceType>()->getPointeeType(); + IsByRef = !Ty->isScalarType(); + } + + // When passing data by value, we need to make sure it fits the uintptr size + // and alignment, because the runtime library only deals with uintptr types. + // If it does not fit the uintptr size, we need to pass the data by reference + // instead. + if (!IsByRef && + (Ctx.getTypeSizeInChars(Ty) > + Ctx.getTypeSizeInChars(Ctx.getUIntPtrType()) || + Ctx.getDeclAlign(VD) > Ctx.getTypeAlignInChars(Ctx.getUIntPtrType()))) + IsByRef = true; + + return IsByRef; +} + bool Sema::IsOpenMPCapturedVar(VarDecl *VD) { assert(LangOpts.OpenMP && "OpenMP is not allowed"); VD = VD->getCanonicalDecl(); @@ -5015,7 +5112,13 @@ StmtResult Sema::ActOnOpenMPTargetDirective(ArrayRef<OMPClause *> Clauses, if (!AStmt) return StmtError(); - assert(isa<CapturedStmt>(AStmt) && "Captured statement expected"); + CapturedStmt *CS = cast<CapturedStmt>(AStmt); + // 1.2.2 OpenMP Language Terminology + // Structured block - An executable statement with a single entry at the + // top and a single exit at the bottom. + // The point of exit cannot be a branch out of the structured block. + // longjmp() and throw() must not violate the entry/exit criteria. + CS->getCapturedDecl()->setNothrow(); // OpenMP [2.16, Nesting of Regions] // If specified, a teams construct must be contained within a target |
