[OPENMP] Do not capture private loop counters.
If the loop counter is not declared in the context of the loop and it is
private, such loop counters should not be captured in the outlined
regions.
llvm-svn: 345505
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 92d1514..a6d1a11 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -138,9 +138,11 @@
/// 'ordered' clause, the second one is true if the regions has 'ordered'
/// clause, false otherwise.
llvm::Optional<std::pair<const Expr *, OMPOrderedClause *>> OrderedRegion;
+ unsigned AssociatedLoops = 1;
+ const Decl *PossiblyLoopCounter = nullptr;
bool NowaitRegion = false;
bool CancelRegion = false;
- unsigned AssociatedLoops = 1;
+ bool LoopStart = false;
SourceLocation InnerTeamsRegionLoc;
/// Reference to the taskgroup task_reduction reference expression.
Expr *TaskgroupReductionRef = nullptr;
@@ -208,6 +210,33 @@
Stack.back().first.pop_back();
}
+ /// Marks that we're started loop parsing.
+ void loopInit() {
+ assert(isOpenMPLoopDirective(getCurrentDirective()) &&
+ "Expected loop-based directive.");
+ Stack.back().first.back().LoopStart = true;
+ }
+ /// Start capturing of the variables in the loop context.
+ void loopStart() {
+ assert(isOpenMPLoopDirective(getCurrentDirective()) &&
+ "Expected loop-based directive.");
+ Stack.back().first.back().LoopStart = false;
+ }
+ /// true, if variables are captured, false otherwise.
+ bool isLoopStarted() const {
+ assert(isOpenMPLoopDirective(getCurrentDirective()) &&
+ "Expected loop-based directive.");
+ return !Stack.back().first.back().LoopStart;
+ }
+ /// Marks (or clears) declaration as possibly loop counter.
+ void resetPossibleLoopCounter(const Decl *D = nullptr) {
+ Stack.back().first.back().PossiblyLoopCounter =
+ D ? D->getCanonicalDecl() : D;
+ }
+ /// Gets the possible loop counter decl.
+ const Decl *getPossiblyLoopCunter() const {
+ return Stack.back().first.back().PossiblyLoopCounter;
+ }
/// Start new OpenMP region stack in new non-capturing function.
void pushFunction() {
const FunctionScopeInfo *CurFnScope = SemaRef.getCurFunction();
@@ -354,7 +383,7 @@
return OMPD_unknown;
return std::next(Stack.back().first.rbegin())->Directive;
}
-
+
/// Add requires decl to internal vector
void addRequiresDecl(OMPRequiresDecl *RD) {
RequiresDecls.push_back(RD);
@@ -1510,8 +1539,28 @@
FunctionScopesIndex -= Regions.size();
}
+void Sema::startOpenMPLoop() {
+ assert(LangOpts.OpenMP && "OpenMP must be enabled.");
+ if (isOpenMPLoopDirective(DSAStack->getCurrentDirective()))
+ DSAStack->loopInit();
+}
+
bool Sema::isOpenMPPrivateDecl(const ValueDecl *D, unsigned Level) const {
assert(LangOpts.OpenMP && "OpenMP is not allowed");
+ if (isOpenMPLoopDirective(DSAStack->getCurrentDirective())) {
+ if (DSAStack->getAssociatedLoops() > 0 &&
+ !DSAStack->isLoopStarted()) {
+ DSAStack->resetPossibleLoopCounter(D);
+ DSAStack->loopStart();
+ return true;
+ }
+ if ((DSAStack->getPossiblyLoopCunter() == D->getCanonicalDecl() ||
+ DSAStack->isLoopControlVariable(D).first) &&
+ !DSAStack->hasExplicitDSA(
+ D, [](OpenMPClauseKind K) { return K != OMPC_private; }, Level) &&
+ !isOpenMPSimdDirective(DSAStack->getCurrentDirective()))
+ return true;
+ }
return DSAStack->hasExplicitDSA(
D, [](OpenMPClauseKind K) { return K == OMPC_private; }, Level) ||
(DSAStack->isClauseParsingMode() &&
@@ -2021,6 +2070,30 @@
Sema::VarsWithInheritedDSAType VarsWithInheritedDSA;
llvm::SmallDenseSet<const ValueDecl *, 4> ImplicitDeclarations;
+ void VisitSubCaptures(OMPExecutableDirective *S) {
+ // Check implicitly captured variables.
+ if (!S->hasAssociatedStmt() || !S->getAssociatedStmt())
+ return;
+ for (const CapturedStmt::Capture &Cap :
+ S->getInnermostCapturedStmt()->captures()) {
+ if (!Cap.capturesVariable())
+ continue;
+ VarDecl *VD = Cap.getCapturedVar();
+ // Do not try to map the variable if it or its sub-component was mapped
+ // already.
+ if (isOpenMPTargetExecutionDirective(Stack->getCurrentDirective()) &&
+ Stack->checkMappableExprComponentListsForDecl(
+ VD, /*CurrentRegionOnly=*/true,
+ [](OMPClauseMappableExprCommon::MappableExprComponentListRef,
+ OpenMPClauseKind) { return true; }))
+ continue;
+ DeclRefExpr *DRE = buildDeclRefExpr(
+ SemaRef, VD, VD->getType().getNonLValueExprType(SemaRef.Context),
+ Cap.getLocation(), /*RefersToCapture=*/true);
+ Visit(DRE);
+ }
+ }
+
public:
void VisitDeclRefExpr(DeclRefExpr *E) {
if (E->isTypeDependent() || E->isValueDependent() ||
@@ -2253,25 +2326,9 @@
for (Stmt *C : S->children()) {
if (C) {
if (auto *OED = dyn_cast<OMPExecutableDirective>(C)) {
- // Check implicitly captured vriables in the task-based directives to
+ // Check implicitly captured variables in the task-based directives to
// check if they must be firstprivatized.
- if (!OED->hasAssociatedStmt())
- continue;
- const Stmt *AS = OED->getAssociatedStmt();
- if (!AS)
- continue;
- for (const CapturedStmt::Capture &Cap :
- cast<CapturedStmt>(AS)->captures()) {
- if (Cap.capturesVariable()) {
- DeclRefExpr *DRE = buildDeclRefExpr(
- SemaRef, Cap.getCapturedVar(),
- Cap.getCapturedVar()->getType().getNonLValueExprType(
- SemaRef.Context),
- Cap.getLocation(),
- /*RefersToCapture=*/true);
- Visit(DRE);
- }
- }
+ VisitSubCaptures(OED);
} else {
Visit(C);
}
@@ -4522,6 +4579,15 @@
}
}
DSAStack->addLoopControlVariable(D, VD);
+ const Decl *LD = DSAStack->getPossiblyLoopCunter();
+ if (LD != D->getCanonicalDecl()) {
+ DSAStack->resetPossibleLoopCounter();
+ if (auto *Var = dyn_cast_or_null<VarDecl>(LD))
+ MarkDeclarationsReferencedInExpr(
+ buildDeclRefExpr(*this, const_cast<VarDecl *>(Var),
+ Var->getType().getNonLValueExprType(Context),
+ ForLoc, /*RefersToCapture=*/true));
+ }
}
}
DSAStack->setAssociatedLoops(AssociatedLoops - 1);