[OPENMP] Emit __kmpc_cancel_barrier() and code for 'cancellation point' only if 'cancel' is found.

Patch improves codegen for OpenMP constructs. If the OpenMP region does not have internal 'cancel' construct, a call to 'void __kmpc_barrier()' runtime function is generated for all implicit/explicit barriers. If the region has inner 'cancel' directive, then
```
if (__kmpc_cancel_barrier())
  exit from outer construct;
```
code is generated.
Also, the code for 'canellation point' directive is not generated if parent directive does not have 'cancel' directive.

llvm-svn: 247681

1 files changed, 75 insertions, 0 deletions

diff --git a/clang/test/OpenMP/cancellation_point_codegen.cpp b/clang/test/OpenMP/cancellation_point_codegen.cpp
index 453393082ce..ee557fd065d 100644
--- a/clang/test/OpenMP/cancellation_point_codegen.cpp
+++ b/clang/test/OpenMP/cancellation_point_codegen.cpp
@@ -11,12 +11,16 @@ int main (int argc, char **argv) {
 #pragma omp parallel
 {
 #pragma omp cancellation point parallel
+#pragma omp cancel parallel
   argv[0][0] = argc;
 }
 // CHECK: call void (%ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(
 #pragma omp sections
 {
+  {
 #pragma omp cancellation point sections
+#pragma omp cancel sections
+  }
 }
 // CHECK: call i32 @__kmpc_single(
 // CHECK-NOT: @__kmpc_cancellationpoint
@@ -28,6 +32,7 @@ int main (int argc, char **argv) {
 #pragma omp section
   {
 #pragma omp cancellation point sections
+#pragma omp cancel sections
   }
 }
 // CHECK: call void @__kmpc_for_static_init_4(
@@ -51,6 +56,7 @@ int main (int argc, char **argv) {
 #pragma omp for
 for (int i = 0; i < argc; ++i) {
 #pragma omp cancellation point for
+#pragma omp cancel for
 }
 // CHECK: call void @__kmpc_for_static_init_4(
 // CHECK: [[RES:%.+]] = call i32 @__kmpc_cancellationpoint(%ident_t* {{[^,]+}}, i32 [[GTID]], i32 2)
@@ -66,9 +72,36 @@ for (int i = 0; i < argc; ++i) {
 #pragma omp task
 {
 #pragma omp cancellation point taskgroup
+#pragma omp cancel taskgroup
 }
 // CHECK: call i8* @__kmpc_omp_task_alloc(
 // CHECK: call i32 @__kmpc_omp_task(
+#pragma omp parallel sections
+{
+  {
+#pragma omp cancellation point sections
+#pragma omp cancel sections
+  }
+}
+// CHECK: call void (%ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(
+#pragma omp parallel sections
+{
+  {
+#pragma omp cancellation point sections
+#pragma omp cancel sections
+  }
+#pragma omp section
+  {
+#pragma omp cancellation point sections
+  }
+}
+// CHECK: call void (%ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(
+#pragma omp parallel for
+for (int i = 0; i < argc; ++i) {
+#pragma omp cancellation point for
+#pragma omp cancel for
+}
+// CHECK: call void (%ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(
   return argc;
 }
 
@@ -92,4 +125,46 @@ for (int i = 0; i < argc; ++i) {
 // CHECK: [[RETURN]]
 // CHECK: ret i32 0
 
+// CHECK: define internal void @{{[^(]+}}(i32* {{[^,]+}}, i32* {{[^,]+}})
+// CHECK: call i32 @__kmpc_single(
+// CHECK-NOT: @__kmpc_cancellationpoint
+// CHECK: call void @__kmpc_end_single(
+// CHECK: call void @__kmpc_barrier(%ident_t*
+// CHECK: ret void
+
+// CHECK: define internal void @{{[^(]+}}(i32* {{[^,]+}}, i32* {{[^,]+}})
+// CHECK: call void @__kmpc_for_static_init_4(
+// CHECK: [[RES:%.+]] = call i32 @__kmpc_cancellationpoint(%ident_t* {{[^,]+}}, i32 [[GTID:%.+]], i32 3)
+// CHECK: [[CMP:%.+]] = icmp ne i32 [[RES]], 0
+// CHECK: br i1 [[CMP]], label %[[EXIT:[^,].+]], label %[[CONTINUE:.+]]
+// CHECK: [[EXIT]]
+// CHECK: call i32 @__kmpc_cancel_barrier(%ident_t*
+// CHECK: br label
+// CHECK: [[CONTINUE]]
+// CHECK: br label
+// CHECK: [[RES:%.+]] = call i32 @__kmpc_cancellationpoint(%ident_t* {{[^,]+}}, i32 [[GTID]], i32 3)
+// CHECK: [[CMP:%.+]] = icmp ne i32 [[RES]], 0
+// CHECK: br i1 [[CMP]], label %[[EXIT:[^,].+]], label %[[CONTINUE:.+]]
+// CHECK: [[EXIT]]
+// CHECK: call i32 @__kmpc_cancel_barrier(%ident_t*
+// CHECK: br label
+// CHECK: [[CONTINUE]]
+// CHECK: br label
+// CHECK: call void @__kmpc_for_static_fini(
+// CHECK: ret void
+
+// CHECK: define internal void @{{[^(]+}}(i32* {{[^,]+}}, i32* {{[^,]+}},
+// CHECK: call void @__kmpc_for_static_init_4(
+// CHECK: [[RES:%.+]] = call i32 @__kmpc_cancellationpoint(%ident_t* {{[^,]+}}, i32 [[GTID:%.+]], i32 2)
+// CHECK: [[CMP:%.+]] = icmp ne i32 [[RES]], 0
+// CHECK: br i1 [[CMP]], label %[[EXIT:[^,].+]], label %[[CONTINUE:.+]]
+// CHECK: [[EXIT]]
+// CHECK: call i32 @__kmpc_cancel_barrier(%ident_t*
+// CHECK: br label
+// CHECK: [[CONTINUE]]
+// CHECK: br label
+// CHECK: call void @__kmpc_for_static_fini(
+// CHECK: call void @__kmpc_barrier(%ident_t*
+// CHECK: ret void
+
 #endif