[OPENMP] Codegen for 'if' clause in 'parallel' directive.

Adds codegen for 'if' clause. Currently only for 'if' clause used with the 'parallel' directive.
If condition evaluates to true, the code executes parallel version of the code by calling __kmpc_fork_call(loc, 1, microtask, captured_struct/*context*/), where loc - debug location, 1 - number of additional parameters after "microtask" argument, microtask - is outlined finction for the code associated with the 'parallel' directive, captured_struct - list of variables captured in this outlined function.
If condition evaluates to false, the code executes serial version of the code by executing the following code:

global_thread_id.addr = alloca i32
store i32 global_thread_id, global_thread_id.addr
zero.addr = alloca i32
store i32 0, zero.addr
kmpc_serialized_parallel(loc, global_thread_id);
microtask(global_thread_id.addr, zero.addr, captured_struct/*context*/);
kmpc_end_serialized_parallel(loc, global_thread_id);

Where loc - debug location, global_thread_id - global thread id, returned by __kmpc_global_thread_num() call or passed as a first parameter in microtask() call, global_thread_id.addr - address of the variable, where stored global_thread_id value, zero.addr - implicit bound thread id (should be set to 0 for serial call), microtask() and captured_struct are the same as in parallel call.

Also this patch checks if the condition is constant and if it is constant it evaluates its value and then generates either parallel version of the code (if the condition evaluates to true), or the serial version of the code (if the condition evaluates to false).
Differential Revision: http://reviews.llvm.org/D4716


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219597 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 124 insertions, 0 deletions

diff --git a/test/OpenMP/parallel_if_codegen.cpp b/test/OpenMP/parallel_if_codegen.cpp
new file mode 100644
index 0000000000..54eedbefe5
--- /dev/null
+++ b/test/OpenMP/parallel_if_codegen.cpp
@@ -0,0 +1,124 @@
+// RUN: %clang_cc1 -verify -fopenmp=libiomp5 -x c++ -triple %itanium_abi_triple -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -fopenmp=libiomp5 -x c++ -std=c++11 -triple %itanium_abi_triple -emit-pch -o %t %s
+// RUN: %clang_cc1 -fopenmp=libiomp5 -x c++ -triple %itanium_abi_triple -std=c++11 -include-pch %t -verify %s -emit-llvm -o - | FileCheck --check-prefix=CHECK %s
+// expected-no-diagnostics
+#ifndef HEADER
+#define HEADER
+
+void fn1();
+void fn2();
+void fn3();
+void fn4();
+void fn5();
+void fn6();
+
+int Arg;
+
+// CHECK-LABEL: define void @{{.+}}gtid_test
+void gtid_test() {
+// CHECK:  call void {{.+}}* @__kmpc_fork_call(%{{.+}}* @{{.+}}, i{{.+}} 1, {{.+}}* [[GTID_TEST_REGION1:@.+]] to void
+#pragma omp parallel
+#pragma omp parallel if (false)
+  gtid_test();
+// CHECK: ret void
+}
+
+// CHECK: define internal void [[GTID_TEST_REGION1]](i{{.+}}* [[GTID_PARAM:%.+]], i
+// CHECK: store i{{[0-9]+}}* [[GTID_PARAM]], i{{[0-9]+}}** [[GTID_ADDR_REF:%.+]],
+// CHECK: [[GTID_ADDR:%.+]] = load i{{[0-9]+}}** [[GTID_ADDR_REF]]
+// CHECK: [[GTID:%.+]] = load i{{[0-9]+}}* [[GTID_ADDR]]
+// CHECK: call void @__kmpc_serialized_parallel(%{{.+}}* @{{.+}}, i{{.+}} [[GTID]])
+// CHECK: [[GTID_ADDR:%.+]] = load i{{[0-9]+}}** [[GTID_ADDR_REF]]
+// CHECK: call void [[GTID_TEST_REGION2:@.+]](i{{[0-9]+}}* [[GTID_ADDR]]
+// CHECK: call void @__kmpc_end_serialized_parallel(%{{.+}}* @{{.+}}, i{{.+}} [[GTID]])
+// CHECK: ret void
+
+// CHECK: define internal void [[GTID_TEST_REGION2]](
+// CHECK: call void @{{.+}}gtid_test
+// CHECK: ret void
+
+template <typename T>
+int tmain(T Arg) {
+#pragma omp parallel if (true)
+  fn1();
+#pragma omp parallel if (false)
+  fn2();
+#pragma omp parallel if (Arg)
+  fn3();
+  return 0;
+}
+
+// CHECK-LABEL: define {{.*}}i{{[0-9]+}} @main()
+int main() {
+// CHECK: [[GTID:%.+]] = call i32 @__kmpc_global_thread_num(
+// CHECK: call void {{.+}} @__kmpc_fork_call(%{{.+}}* @{{.+}}, i{{.+}} 1, void {{.+}}* [[CAP_FN4:@.+]] to void
+#pragma omp parallel if (true)
+  fn4();
+// CHECK: call void @__kmpc_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+// CHECK: store i32 [[GTID]], i32* [[GTID_ADDR:%.+]],
+// CHECK: call void [[CAP_FN5:@.+]](i32* [[GTID_ADDR]],
+// CHECK: call void @__kmpc_end_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+#pragma omp parallel if (false)
+  fn5();
+
+// CHECK: br i1 %{{.+}}, label %[[OMP_THEN:.+]], label %[[OMP_ELSE:.+]]
+// CHECK: [[OMP_THEN]]
+// CHECK: call void {{.+}} @__kmpc_fork_call(%{{.+}}* @{{.+}}, i{{.+}} 1, void {{.+}}* [[CAP_FN6:@.+]] to void
+// CHECK: br label %[[OMP_END:.+]]
+// CHECK: [[OMP_ELSE]]
+// CHECK: call void @__kmpc_serialized_parallel(%{{.+}}* @{{.+}}, i32 %0)
+// CHECK: store i32 [[GTID]], i32* [[GTID_ADDR:%.+]],
+// CHECK: call void [[CAP_FN6]](i32* [[GTID_ADDR]],
+// CHECK: call void @__kmpc_end_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+// CHECK: br label %[[OMP_END]]
+// CHECK: [[OMP_END]]
+#pragma omp parallel if (Arg)
+  fn6();
+  // CHECK: = call i{{.+}} @{{.+}}tmain
+  return tmain(Arg);
+}
+
+// CHECK: define internal void [[CAP_FN4]]
+// CHECK: call void @{{.+}}fn4
+// CHECK: ret void
+
+// CHECK: define internal void [[CAP_FN5]]
+// CHECK: call void @{{.+}}fn5
+// CHECK: ret void
+
+// CHECK: define internal void [[CAP_FN6]]
+// CHECK: call void @{{.+}}fn6
+// CHECK: ret void
+
+// CHECK-LABEL: define {{.+}} @{{.+}}tmain
+// CHECK: [[GTID:%.+]] = call i32 @__kmpc_global_thread_num(
+// CHECK: call void {{.+}} @__kmpc_fork_call(%{{.+}}* @{{.+}}, i{{.+}} 1, void {{.+}}* [[CAP_FN1:@.+]] to void
+// CHECK: call void @__kmpc_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+// CHECK: store i32 [[GTID]], i32* [[GTID_ADDR:%.+]],
+// CHECK: call void [[CAP_FN2:@.+]](i32* [[GTID_ADDR]],
+// CHECK: call void @__kmpc_end_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+// CHECK: br i1 %{{.+}}, label %[[OMP_THEN:.+]], label %[[OMP_ELSE:.+]]
+// CHECK: [[OMP_THEN]]
+// CHECK: call void {{.+}} @__kmpc_fork_call(%{{.+}}* @{{.+}}, i{{.+}} 1, void {{.+}}* [[CAP_FN3:@.+]] to void
+// CHECK: br label %[[OMP_END:.+]]
+// CHECK: [[OMP_ELSE]]
+// CHECK: call void @__kmpc_serialized_parallel(%{{.+}}* @{{.+}}, i32 %0)
+// CHECK: store i32 [[GTID]], i32* [[GTID_ADDR:%.+]],
+// CHECK: call void [[CAP_FN3]](i32* [[GTID_ADDR]],
+// CHECK: call void @__kmpc_end_serialized_parallel(%{{.+}}* @{{.+}}, i32 [[GTID]])
+// CHECK: br label %[[OMP_END]]
+// CHECK: [[OMP_END]]
+
+// CHECK: define internal void [[CAP_FN1]]
+// CHECK: call void @{{.+}}fn1
+// CHECK: ret void
+
+// CHECK: define internal void [[CAP_FN2]]
+// CHECK: call void @{{.+}}fn2
+// CHECK: ret void
+
+// CHECK: define internal void [[CAP_FN3]]
+// CHECK: call void @{{.+}}fn3
+// CHECK: ret void
+
+#endif