[NFC][OpenMP] Add new test for parallel for code generation.

[gtbercea]

Summary

This is a simple test of the parallel for code generation. It will be used to showcase the change introduced by patch D53443.

[ABataev]

LG

test/OpenMP/nvptx_parallel_for_codegen.cpp

+// Test target codegen - host bc file has to be created first.
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple nvptx64-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-64
+// expected-no-diagnostics
+#ifndef HEADER
+#define HEADER
+
+template<typename tx>
+tx ftemplate(int n) {
+  tx b[10];
+
+  #pragma omp target
+  {
+    tx d = n;
+    #pragma omp parallel for
+    for(int i=0; i<10; i++) {
+      b[i] += d;
+    }
+    b[3] += 1;
+  }
+
+  return b[3];
+}
+
+int bar(int n){
+  int a = 0;
+
+  a += ftemplate<int>(n);
+
+  return a;
+}
+
+// CHECK-LABEL: define {{.*}}void {{@__omp_offloading_.+template.+l12}}_worker()
+// CHECK: call void @llvm.nvvm.barrier0()
+// CHECK: call i1 @__kmpc_kernel_parallel(
+// CHECK: call void @__omp_outlined___wrapper(
+
+// CHECK: define weak void @__omp_offloading_{{.*}}l12(
+// CHECK: call void @__omp_offloading_{{.*}}l12_worker()
+// CHECK: call void @__kmpc_kernel_init(
+// CHECK: call void @__kmpc_data_sharing_init_stack()
+// CHECK: call i8* @__kmpc_data_sharing_push_stack(i64 4, i16 0)
+// CHECK: call void @__kmpc_kernel_prepare_parallel(
+// CHECK: call void @__kmpc_begin_sharing_variables({{.*}}, i64 2)
+// CHECK: call void @llvm.nvvm.barrier0()
+// CHECK: call void @llvm.nvvm.barrier0()
+// CHECK: call void @__kmpc_end_sharing_variables()
+// CHECK: call void @__kmpc_data_sharing_pop_stack(
+// CHECK: call void @__kmpc_kernel_deinit(i16 1)
+
+// CHECK: define internal void @__omp_outlined__(
+// CHECK: alloca
+// CHECK: alloca
+// CHECK: alloca
+// CHECK: alloca
+// CHECK: [[OMP_IV:%.*]] = alloca i32
+// CHECK: store i32 0, {{.*}} [[OMP_LB:%.+]],
+// CHECK: store i32 9, {{.*}} [[OMP_UB:%.+]],
+// CHECK: store i32 1, {{.*}} [[OMP_ST:%.+]],
+// CHECK: call void @__kmpc_for_static_init_4({{.*}} i32 34, {{.*}} [[OMP_LB]], {{.*}} [[OMP_UB]], {{.*}} [[OMP_ST]], i32 1, i32 1)
+// CHECK: [[OMP_UB_1:%.+]] = load {{.*}} [[OMP_UB]]
+// CHECK: [[COMP_1:%.+]] = icmp sgt {{.*}} [[OMP_UB_1]]
+// CHECK: br i1 [[COMP_1]], label %[[COND_TRUE:.+]], label %[[COND_FALSE:.+]]
+
+// CHECK: [[COND_TRUE]]
+// CHECK: br label %[[COND_END:.+]]
+
+// CHECK: [[COND_FALSE]]
+// CHECK: [[OMP_UB_2:%.+]] = load {{.*}}* [[OMP_UB]]
+// CHECK: br label %[[COND_END]]
+
+// CHECK: [[COND_END]]
+// CHECK: [[COND_RES:%.+]] = phi i32 [ 9, %[[COND_TRUE]] ], [ [[OMP_UB_2]], %[[COND_FALSE]] ]
+// CHECK: store i32 [[COND_RES]], i32* [[OMP_UB]]
+// CHECK: [[OMP_LB_1:%.+]] = load i32, i32* [[OMP_LB]]
+// CHECK: store i32 [[OMP_LB_1]], i32* [[OMP_IV]]
+// CHECK: br label %[[OMP_INNER_FOR_COND:.+]]
+
+// CHECK: [[OMP_INNER_FOR_COND]]
+// CHECK: [[OMP_IV_2:%.+]] = load i32, i32* [[OMP_IV]]
+// CHECK: [[OMP_UB_4:%.+]] = load i32, i32* [[OMP_UB]]
+// CHECK: [[COMP_3:%.+]] = icmp sle i32 [[OMP_IV_2]], [[OMP_UB_4]]
+// CHECK: br i1 [[COMP_3]], label %[[OMP_INNER_FOR_BODY:.+]], label %[[OMP_INNER_FOR_END:.+]]
+
+// CHECK: [[OMP_INNER_FOR_BODY]]
+// CHECK: br label %[[OMP_BODY_CONTINUE:.+]]
+
+// CHECK: [[OMP_BODY_CONTINUE]]
+// CHECK: br label %[[OMP_INNER_FOR_INC:.+]]
+
+// CHECK: [[OMP_INNER_FOR_INC]]
+// CHECK: [[OMP_IV_3:%.+]] = load i32, i32* [[OMP_IV]]
+// CHECK: [[ADD_1:%.+]] = add nsw i32 [[OMP_IV_3]], 1
+// CHECK: store i32 [[ADD_1]], i32* [[OMP_IV]]
+// CHECK: br label %[[OMP_INNER_FOR_COND]]
+
+// CHECK: [[OMP_INNER_FOR_END]]
+// CHECK: call void @__kmpc_for_static_fini(
+// CHECK: ret void
+
+#endif