Reset cancellation status for 'parallel', 'sections' and 'for' constr…

…acts.

Without this fix cancellation status for parallel, sections and for persists 
across construct boundaries.

Differential Revision: https://reviews.llvm.org/D31419

llvm-svn: 299434

openmp/runtime/src/kmp_barrier.cpp

@@ -1212,6 +1212,13 @@ __kmp_barrier(enum barrier_type bt, int gtid, int is_split, size_t reduce_size,
             team->t.t_bar[bt].b_team_arrived += 1;
 #endif
 
+#if OMP_40_ENABLED
+      // Reset cancellation flag for worksharing constructs
+      if(team->t.t_cancel_request == cancel_loop ||
+         team->t.t_cancel_request == cancel_sections ) {
+        team->t.t_cancel_request = cancel_noreq;
+      }
+#endif
 #if USE_ITT_BUILD
             /* TODO: In case of split reduction barrier, master thread may send acquired event early,
                before the final summation into the shared variable is done (final summation can be a

openmp/runtime/src/kmp_runtime.cpp

@@ -1372,6 +1372,9 @@ __kmp_serialized_parallel(ident_t *loc, kmp_int32 global_tid)
 
         KMP_MB();
     }
+#if OMP_40_ENABLED
+    KMP_CHECK_UPDATE(serial_team->t.t_cancel_request, cancel_noreq);
+#endif
 
     if ( __kmp_env_consistency_check )
         __kmp_push_parallel( global_tid, NULL );

openmp/runtime/test/misc_bugs/cancellation_for_sections.c

@@ -0,0 +1,61 @@
+// RUN: %libomp-compile && env OMP_CANCELLATION=true %libomp-run
+// Regression test for a bug in cancellation to cover effect of `#pragma omp cancel`
+// in a loop construct, on sections construct.
+// Pass condition: Cancellation status from `for` does not persist
+// to `sections`.
+
+#include <stdio.h>
+#include <omp.h>
+
+int result[2] = {0, 0};
+
+void cq416850_for_sections() {
+
+    unsigned i;
+     // 1) loop
+    #pragma omp for
+    for (i = 0; i < 1; i++) {
+        result[0] = 1;
+        #pragma omp cancel for
+        result[0] = 2;
+    }
+
+//        printf("thread %d: result[0] = %d, result[1] = %d \n",  omp_get_thread_num(), result[0], result[1]);
+
+
+    // 2) sections
+    #pragma omp sections
+    {
+        #pragma omp section
+        {
+            result[1] = 1;
+            #pragma omp cancellation point sections
+            result[1] = 2;
+        }
+    }
+}
+
+int main(void) {
+    if(!omp_get_cancellation()) {
+        printf("Cancellation not enabled!\n");
+        return 2;
+    }
+
+    #pragma omp parallel num_threads(4)
+    {
+        cq416850_for_sections();
+    }
+
+    if (result[0] != 1 || result[1] != 2) {
+        printf("Incorrect values. "
+               "result[0] = %d (expected 1), "
+               "result[1] = %d (expected 2).\n",
+               result[0], result[1]);
+        printf("FAILED\n");
+        return 1;
+    }
+
+    printf("PASSED\n");
+    return 0;
+}
+