Test codegen of atomic compare-exchange with additional memory orderings

* Add a test for atomic operations introduced in #97423 & #98383.
* Add a test for fallback code generation strategy used on LLVM 12
  introduced in #98385. Use a separate test case instead of a revision
  system since test will be gone once LLVM 12 is no longer supported.

2 files changed, 109 insertions, 1 deletions

diff --git a/src/test/codegen/atomic-operations-llvm-12.rs b/src/test/codegen/atomic-operations-llvm-12.rs
new file mode 100644
index 00000000000..bd4c63dcff1
--- /dev/null
+++ b/src/test/codegen/atomic-operations-llvm-12.rs
@@ -0,0 +1,84 @@
+// Code generation of atomic operations for LLVM 12
+// ignore-llvm-version: 13 - 99
+// compile-flags: -O
+#![crate_type = "lib"]
+
+use std::sync::atomic::{AtomicI32, Ordering::*};
+
+// CHECK-LABEL: @compare_exchange
+#[no_mangle]
+pub fn compare_exchange(a: &AtomicI32) {
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 10 monotonic monotonic
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 11 acquire acquire
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 12 seq_cst seq_cst
+    let _ = a.compare_exchange(0, 10, Relaxed, Relaxed);
+    let _ = a.compare_exchange(0, 11, Relaxed, Acquire);
+    let _ = a.compare_exchange(0, 12, Relaxed, SeqCst);
+
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 20 release monotonic
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 21 acq_rel acquire
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 22 seq_cst seq_cst
+    let _ = a.compare_exchange(0, 20, Release, Relaxed);
+    let _ = a.compare_exchange(0, 21, Release, Acquire);
+    let _ = a.compare_exchange(0, 22, Release, SeqCst);
+
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 30 acquire monotonic
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 31 acquire acquire
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 32 seq_cst seq_cst
+    let _ = a.compare_exchange(0, 30, Acquire, Relaxed);
+    let _ = a.compare_exchange(0, 31, Acquire, Acquire);
+    let _ = a.compare_exchange(0, 32, Acquire, SeqCst);
+
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 40 acq_rel monotonic
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 41 acq_rel acquire
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 42 seq_cst seq_cst
+    let _ = a.compare_exchange(0, 40, AcqRel, Relaxed);
+    let _ = a.compare_exchange(0, 41, AcqRel, Acquire);
+    let _ = a.compare_exchange(0, 42, AcqRel, SeqCst);
+
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 50 seq_cst monotonic
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 51 seq_cst acquire
+    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 52 seq_cst seq_cst
+    let _ = a.compare_exchange(0, 50, SeqCst, Relaxed);
+    let _ = a.compare_exchange(0, 51, SeqCst, Acquire);
+    let _ = a.compare_exchange(0, 52, SeqCst, SeqCst);
+}
+
+// CHECK-LABEL: @compare_exchange_weak
+#[no_mangle]
+pub fn compare_exchange_weak(w: &AtomicI32) {
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 10 monotonic monotonic
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 11 acquire acquire
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 12 seq_cst seq_cst
+    let _ = w.compare_exchange_weak(1, 10, Relaxed, Relaxed);
+    let _ = w.compare_exchange_weak(1, 11, Relaxed, Acquire);
+    let _ = w.compare_exchange_weak(1, 12, Relaxed, SeqCst);
+
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 20 release monotonic
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 21 acq_rel acquire
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 22 seq_cst seq_cst
+    let _ = w.compare_exchange_weak(1, 20, Release, Relaxed);
+    let _ = w.compare_exchange_weak(1, 21, Release, Acquire);
+    let _ = w.compare_exchange_weak(1, 22, Release, SeqCst);
+
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 30 acquire monotonic
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 31 acquire acquire
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 32 seq_cst seq_cst
+    let _ = w.compare_exchange_weak(1, 30, Acquire, Relaxed);
+    let _ = w.compare_exchange_weak(1, 31, Acquire, Acquire);
+    let _ = w.compare_exchange_weak(1, 32, Acquire, SeqCst);
+
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 40 acq_rel monotonic
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 41 acq_rel acquire
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 42 seq_cst seq_cst
+    let _ = w.compare_exchange_weak(1, 40, AcqRel, Relaxed);
+    let _ = w.compare_exchange_weak(1, 41, AcqRel, Acquire);
+    let _ = w.compare_exchange_weak(1, 42, AcqRel, SeqCst);
+
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 50 seq_cst monotonic
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 51 seq_cst acquire
+    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 52 seq_cst seq_cst
+    let _ = w.compare_exchange_weak(1, 50, SeqCst, Relaxed);
+    let _ = w.compare_exchange_weak(1, 51, SeqCst, Acquire);
+    let _ = w.compare_exchange_weak(1, 52, SeqCst, SeqCst);
+}
diff --git a/src/test/codegen/atomic-operations.rs b/src/test/codegen/atomic-operations.rs
index a14f63726bb..771cf58725a 100644
--- a/src/test/codegen/atomic-operations.rs
+++ b/src/test/codegen/atomic-operations.rs
@@ -1,5 +1,5 @@
 // Code generation of atomic operations.
-//
+// min-llvm-version: 13.0
 // compile-flags: -O
 #![crate_type = "lib"]
 
@@ -9,20 +9,32 @@ use std::sync::atomic::{AtomicI32, Ordering::*};
 #[no_mangle]
 pub fn compare_exchange(a: &AtomicI32) {
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 10 monotonic monotonic
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 11 monotonic acquire
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 12 monotonic seq_cst
     let _ = a.compare_exchange(0, 10, Relaxed, Relaxed);
+    let _ = a.compare_exchange(0, 11, Relaxed, Acquire);
+    let _ = a.compare_exchange(0, 12, Relaxed, SeqCst);
 
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 20 release monotonic
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 21 release acquire
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 22 release seq_cst
     let _ = a.compare_exchange(0, 20, Release, Relaxed);
+    let _ = a.compare_exchange(0, 21, Release, Acquire);
+    let _ = a.compare_exchange(0, 22, Release, SeqCst);
 
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 30 acquire monotonic
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 31 acquire acquire
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 32 acquire seq_cst
     let _ = a.compare_exchange(0, 30, Acquire, Relaxed);
     let _ = a.compare_exchange(0, 31, Acquire, Acquire);
+    let _ = a.compare_exchange(0, 32, Acquire, SeqCst);
 
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 40 acq_rel monotonic
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 41 acq_rel acquire
+    // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 42 acq_rel seq_cst
     let _ = a.compare_exchange(0, 40, AcqRel, Relaxed);
     let _ = a.compare_exchange(0, 41, AcqRel, Acquire);
+    let _ = a.compare_exchange(0, 42, AcqRel, SeqCst);
 
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 50 seq_cst monotonic
     // CHECK: cmpxchg {{i32\*|ptr}} %{{.*}}, i32 0, i32 51 seq_cst acquire
@@ -36,20 +48,32 @@ pub fn compare_exchange(a: &AtomicI32) {
 #[no_mangle]
 pub fn compare_exchange_weak(w: &AtomicI32) {
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 10 monotonic monotonic
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 11 monotonic acquire
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 12 monotonic seq_cst
     let _ = w.compare_exchange_weak(1, 10, Relaxed, Relaxed);
+    let _ = w.compare_exchange_weak(1, 11, Relaxed, Acquire);
+    let _ = w.compare_exchange_weak(1, 12, Relaxed, SeqCst);
 
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 20 release monotonic
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 21 release acquire
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 22 release seq_cst
     let _ = w.compare_exchange_weak(1, 20, Release, Relaxed);
+    let _ = w.compare_exchange_weak(1, 21, Release, Acquire);
+    let _ = w.compare_exchange_weak(1, 22, Release, SeqCst);
 
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 30 acquire monotonic
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 31 acquire acquire
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 32 acquire seq_cst
     let _ = w.compare_exchange_weak(1, 30, Acquire, Relaxed);
     let _ = w.compare_exchange_weak(1, 31, Acquire, Acquire);
+    let _ = w.compare_exchange_weak(1, 32, Acquire, SeqCst);
 
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 40 acq_rel monotonic
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 41 acq_rel acquire
+    // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 42 acq_rel seq_cst
     let _ = w.compare_exchange_weak(1, 40, AcqRel, Relaxed);
     let _ = w.compare_exchange_weak(1, 41, AcqRel, Acquire);
+    let _ = w.compare_exchange_weak(1, 42, AcqRel, SeqCst);
 
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 50 seq_cst monotonic
     // CHECK: cmpxchg weak {{i32\*|ptr}} %{{.*}}, i32 1, i32 51 seq_cst acquire