[OPENMP] Codegen for "omp flush" directive.
For each "omp flush" directive a call to "void kmpc_flush(ident_t *, ...)" function is generated.
Directive "omp flush" may have an associated list of variables to flush, but currently runtime function ignores them. So the patch generates just "call kmpc_flush(ident_t *<loc>, i32 0)".
Differential Revision: http://reviews.llvm.org/D6292

llvm-svn: 222409
diff --git a/clang/test/OpenMP/flush_codegen.cpp b/clang/test/OpenMP/flush_codegen.cpp
new file mode 100644
index 0000000..eb9c721
--- /dev/null
+++ b/clang/test/OpenMP/flush_codegen.cpp
@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -verify -fopenmp=libiomp5 -x c++ -emit-llvm %s -fexceptions -fcxx-exceptions -o - | FileCheck %s
+// RUN: %clang_cc1 -fopenmp=libiomp5 -x c++ -std=c++11 -triple x86_64-unknown-unknown -fexceptions -fcxx-exceptions -emit-pch -o %t %s
+// RUN: %clang_cc1 -fopenmp=libiomp5 -x c++ -triple x86_64-unknown-unknown -fexceptions -fcxx-exceptions -g -std=c++11 -include-pch %t -verify %s -emit-llvm -o - | FileCheck %s
+// expected-no-diagnostics
+
+#ifndef HEADER
+#define HEADER
+
+template <class T>
+T tmain(T argc) {
+  static T a;
+#pragma omp flush
+#pragma omp flush(a)
+  return a + argc;
+}
+
+// CHECK-LABEL: @main
+int main() {
+  static int a;
+#pragma omp flush
+#pragma omp flush(a)
+  // CHECK: call void (%{{.+}}*, ...)* @__kmpc_flush(%{{.+}}* {{(@|%).+}}, i32 0)
+  // CHECK: call void (%{{.+}}*, ...)* @__kmpc_flush(%{{.+}}* {{(@|%).+}}, i32 0)
+  return tmain(a);
+  // CHECK: call {{.*}} [[TMAIN:@.+]](
+  // CHECK: ret
+}
+
+// CHECK: [[TMAIN]]
+// CHECK: call void (%{{.+}}*, ...)* @__kmpc_flush(%{{.+}}* {{(@|%).+}}, i32 0)
+// CHECK: call void (%{{.+}}*, ...)* @__kmpc_flush(%{{.+}}* {{(@|%).+}}, i32 0)
+// CHECK: ret
+
+#endif