[clang] 4341c66 - [OPENMP]Do not allow threadprivates as base for array-like reduction.

[Alexey Bataev via cfe-commits]

Author: Alexey Bataev
Date: 2020-09-16T09:30:32-04:00
New Revision: 4341c6618decb4014a167bc83aeeed49ab49b34f

URL: https://github.com/llvm/llvm-project/commit/4341c6618decb4014a167bc83aeeed49ab49b34f
DIFF: https://github.com/llvm/llvm-project/commit/4341c6618decb4014a167bc83aeeed49ab49b34f.diff

LOG: [OPENMP]Do not allow threadprivates as base for array-like reduction.

The base must be shared between the threads, threadprivates are not
allowed to be bases for array-like reductions.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D85762

Added: 
    

Modified: 
    clang/lib/Sema/SemaOpenMP.cpp
    clang/test/OpenMP/parallel_reduction_messages.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 336f26422914..1a0470a9606d 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -15120,6 +15120,17 @@ static bool actOnOMPReductionKindClause(
           continue;
         }
       }
+    } else {
+      // Threadprivates cannot be shared between threads, so dignose if the base
+      // is a threadprivate variable.
+      DSAStackTy::DSAVarData DVar = Stack->getTopDSA(D, /*FromParent=*/false);
+      if (DVar.CKind == OMPC_threadprivate) {
+        S.Diag(ELoc, diag::err_omp_wrong_dsa)
+            << getOpenMPClauseName(DVar.CKind)
+            << getOpenMPClauseName(OMPC_reduction);
+        reportOriginalDsa(S, Stack, D, DVar);
+        continue;
+      }
     }
 
     // Try to find 'declare reduction' corresponding construct before using

diff  --git a/clang/test/OpenMP/parallel_reduction_messages.cpp b/clang/test/OpenMP/parallel_reduction_messages.cpp
index b464bf5b9643..12b34a4de07b 100644
--- a/clang/test/OpenMP/parallel_reduction_messages.cpp
+++ b/clang/test/OpenMP/parallel_reduction_messages.cpp
@@ -92,6 +92,8 @@ class S6 { // expected-note 3 {{candidate function (the implicit copy assignment
 
 S3 h, k;
 #pragma omp threadprivate(h) // expected-note 2 {{defined as threadprivate or thread local}}
+int *gptr;
+#pragma omp threadprivate(gptr) // expected-note {{defined as threadprivate or thread local}}
 
 template <class T>       // expected-note {{declared here}}
 T tmain(T argc) {
@@ -277,6 +279,8 @@ int main(int argc, char **argv) {
   m++;
 #pragma omp parallel reduction(task, + : m) // omp45-error 2 {{expected expression}} omp45-warning {{missing ':' after reduction identifier - ignoring}}
   m++;
+#pragma omp parallel reduction(+:gptr[:argc]) // expected-error {{threadprivate or thread local variable cannot be reduction}}
+  ;
 
   return tmain(argc) + tmain(fl); // expected-note {{in instantiation of function template specialization 'tmain<int>' requested here}} expected-note {{in instantiation of function template specialization 'tmain<float>' requested here}}
 }