[OpenMP] Correctly code-gen default atomic mem order (#97663)

Summary:
The parsing for this was implemented, but we never hooked up the default
value to the result of this clause. This patch adds the support by
making it default to the requires directive.

1 files changed, 46 insertions, 0 deletions

diff --git a/clang/test/OpenMP/requires_default_atomic_mem_order.cpp b/clang/test/OpenMP/requires_default_atomic_mem_order.cpp
new file mode 100644
index 0000000..90d2db4
--- /dev/null
+++ b/clang/test/OpenMP/requires_default_atomic_mem_order.cpp
@@ -0,0 +1,46 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+// RUN: %clang_cc1 -emit-llvm -fopenmp -triple=x86_64-unknown-linux-gnu \
+// RUN:   -DORDERING=seq_cst -o - %s \
+// RUN: | FileCheck %s --check-prefix=SEQ_CST
+// RUN: %clang_cc1 -emit-llvm -fopenmp -triple=x86_64-unknown-linux-gnu \
+// RUN:   -DORDERING=acq_rel -o - %s \
+// RUN: | FileCheck %s --check-prefix=ACQ_REL
+// RUN: %clang_cc1 -emit-llvm -fopenmp -triple=x86_64-unknown-linux-gnu \
+// RUN:   -DORDERING=relaxed -o - %s \
+// RUN: | FileCheck %s --check-prefix=RELAXED
+
+#pragma omp requires atomic_default_mem_order(ORDERING)
+
+// SEQ_CST-LABEL: define dso_local void @_Z3fooPi(
+// SEQ_CST-SAME: ptr noundef [[X:%.*]]) #[[ATTR0:[0-9]+]] {
+// SEQ_CST-NEXT:  [[ENTRY:.*:]]
+// SEQ_CST-NEXT:    [[X_ADDR:%.*]] = alloca ptr, align 8
+// SEQ_CST-NEXT:    store ptr [[X]], ptr [[X_ADDR]], align 8
+// SEQ_CST-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[X_ADDR]], align 8
+// SEQ_CST-NEXT:    [[TMP1:%.*]] = atomicrmw add ptr [[TMP0]], i32 1 seq_cst, align 4
+// SEQ_CST-NEXT:    call void @__kmpc_flush(ptr @[[GLOB1:[0-9]+]])
+// SEQ_CST-NEXT:    ret void
+//
+// ACQ_REL-LABEL: define dso_local void @_Z3fooPi(
+// ACQ_REL-SAME: ptr noundef [[X:%.*]]) #[[ATTR0:[0-9]+]] {
+// ACQ_REL-NEXT:  [[ENTRY:.*:]]
+// ACQ_REL-NEXT:    [[X_ADDR:%.*]] = alloca ptr, align 8
+// ACQ_REL-NEXT:    store ptr [[X]], ptr [[X_ADDR]], align 8
+// ACQ_REL-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[X_ADDR]], align 8
+// ACQ_REL-NEXT:    [[TMP1:%.*]] = atomicrmw add ptr [[TMP0]], i32 1 release, align 4
+// ACQ_REL-NEXT:    call void @__kmpc_flush(ptr @[[GLOB1:[0-9]+]])
+// ACQ_REL-NEXT:    ret void
+//
+// RELAXED-LABEL: define dso_local void @_Z3fooPi(
+// RELAXED-SAME: ptr noundef [[X:%.*]]) #[[ATTR0:[0-9]+]] {
+// RELAXED-NEXT:  [[ENTRY:.*:]]
+// RELAXED-NEXT:    [[X_ADDR:%.*]] = alloca ptr, align 8
+// RELAXED-NEXT:    store ptr [[X]], ptr [[X_ADDR]], align 8
+// RELAXED-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[X_ADDR]], align 8
+// RELAXED-NEXT:    [[TMP1:%.*]] = atomicrmw add ptr [[TMP0]], i32 1 monotonic, align 4
+// RELAXED-NEXT:    ret void
+//
+void foo(int *x) {
+  #pragma omp atomic update
+    *x = *x + 1;
+}