[OpenMP] Prevent nesting of target constructs within target code execution regions.

Summary:
This patch enhances Sema to check for the following restriction:

OpenMP 4.5 [2.17 Nesting of Regions]
If a target, target update, target data, target enter data, or
target exit data construct is encountered during execution of a
target region, the behavior is unspecified.

Reviewers: ABataev

Differential Revision: http://reviews.llvm.org/D16758

llvm-svn: 259464

1 files changed, 21 insertions, 0 deletions

diff --git a/clang/test/OpenMP/target_parallel_num_threads_messages.cpp b/clang/test/OpenMP/target_parallel_num_threads_messages.cpp
index 4de151fa4ce..95797caf296 100644
--- a/clang/test/OpenMP/target_parallel_num_threads_messages.cpp
+++ b/clang/test/OpenMP/target_parallel_num_threads_messages.cpp
@@ -14,16 +14,27 @@ struct S1; // expected-note {{declared here}}
 template <class T, typename S, int N> // expected-note {{declared here}}
 T tmain(T argc, S **argv) {
   #pragma omp target parallel num_threads // expected-error {{expected '(' after 'num_threads'}}
+  foo();
   #pragma omp target parallel num_threads ( // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
   #pragma omp target parallel num_threads () // expected-error {{expected expression}}
+  foo();
   #pragma omp target parallel num_threads (argc // expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
   #pragma omp target parallel num_threads (argc)) // expected-warning {{extra tokens at the end of '#pragma omp target parallel' are ignored}}
+  foo();
   #pragma omp target parallel num_threads ((argc > 0) ? argv[1] : argv[2]) // expected-error 2 {{expression must have integral or unscoped enumeration type, not 'char *'}}
+  foo();
   #pragma omp target parallel num_threads (foobool(argc)), num_threads (true), num_threads (-5) // expected-error 2 {{directive '#pragma omp target parallel' cannot contain more than one 'num_threads' clause}} expected-error {{argument to 'num_threads' clause must be a strictly positive integer value}}
+  foo();
   #pragma omp target parallel num_threads (S) // expected-error {{'S' does not refer to a value}}
+  foo();
   #pragma omp target parallel num_threads (argv[1]=2) // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error 2 {{expression must have integral or unscoped enumeration type, not 'char *'}}
+  foo();
   #pragma omp target parallel num_threads (argc)
+  foo();
   #pragma omp target parallel num_threads (N) // expected-error {{argument to 'num_threads' clause must be a strictly positive integer value}}
+  foo();
   #pragma omp target parallel redef_num_threads (argc, argc)
   foo();
 
@@ -32,15 +43,25 @@ T tmain(T argc, S **argv) {
 
 int main(int argc, char **argv) {
   #pragma omp target parallel num_threads // expected-error {{expected '(' after 'num_threads'}}
+  foo();
   #pragma omp target parallel num_threads ( // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
   #pragma omp target parallel num_threads () // expected-error {{expected expression}}
+  foo();
   #pragma omp target parallel num_threads (argc // expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
   #pragma omp target parallel num_threads (argc)) // expected-warning {{extra tokens at the end of '#pragma omp target parallel' are ignored}}
+  foo();
   #pragma omp target parallel num_threads (argc > 0 ? argv[1] : argv[2]) // expected-error {{integral }}
+  foo();
   #pragma omp target parallel num_threads (foobool(argc)), num_threads (true), num_threads (-5) // expected-error 2 {{directive '#pragma omp target parallel' cannot contain more than one 'num_threads' clause}} expected-error {{argument to 'num_threads' clause must be a strictly positive integer value}}
+  foo();
   #pragma omp target parallel num_threads (S1) // expected-error {{'S1' does not refer to a value}}
+  foo();
   #pragma omp target parallel num_threads (argv[1]=2) // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expression must have integral or unscoped enumeration type, not 'char *'}}
+  foo();
   #pragma omp target parallel num_threads (num_threads(tmain<int, char, -1>(argc, argv) // expected-error 2 {{expected ')'}} expected-note 2 {{to match this '('}} expected-note {{in instantiation of function template specialization 'tmain<int, char, -1>' requested here}}
+  foo();
   #pragma omp target parallel redef_num_threads (argc, argc)
   foo();