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authorGuillaume Gomez <guillaume1.gomez@gmail.com>2025-07-21 14:34:12 +0200
committerGuillaume Gomez <guillaume1.gomez@gmail.com>2025-07-22 14:28:48 +0200
commita27f3e3fd1e4d16160f8885b6b06665b5319f56c (patch)
treeb033935392cbadf6f85d2dbddf433a88e323aeeb /tests/codegen-llvm/atomicptr.rs
parented93c1783b404d728d4809973a0550eb33cd293f (diff)
downloadrust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.tar.gz
rust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.zip
Rename `tests/codegen` into `tests/codegen-llvm`
Diffstat (limited to 'tests/codegen-llvm/atomicptr.rs')
-rw-r--r--tests/codegen-llvm/atomicptr.rs36
1 files changed, 36 insertions, 0 deletions
diff --git a/tests/codegen-llvm/atomicptr.rs b/tests/codegen-llvm/atomicptr.rs
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+// LLVM does not support some atomic RMW operations on pointers, so inside codegen we lower those
+// to integer atomics, surrounded by casts to and from integer type.
+// This test ensures that we do the round-trip correctly for AtomicPtr::fetch_byte_add, and also
+// ensures that we do not have such a round-trip for AtomicPtr::swap, because LLVM supports pointer
+// arguments to `atomicrmw xchg`.
+
+//@ compile-flags: -Copt-level=3 -Cno-prepopulate-passes
+#![crate_type = "lib"]
+#![feature(strict_provenance_atomic_ptr)]
+
+use std::ptr::without_provenance_mut;
+use std::sync::atomic::AtomicPtr;
+use std::sync::atomic::Ordering::Relaxed;
+
+// Portability hack so that we can say [[USIZE]] instead of i64/i32/i16 for usize.
+// CHECK: @helper([[USIZE:i[0-9]+]] noundef %_1)
+#[no_mangle]
+pub fn helper(_: usize) {}
+
+// CHECK-LABEL: @atomicptr_fetch_byte_add
+#[no_mangle]
+pub fn atomicptr_fetch_byte_add(a: &AtomicPtr<u8>, v: usize) -> *mut u8 {
+    // CHECK: %[[INTPTR:.*]] = ptrtoint ptr %{{.*}} to [[USIZE]]
+    // CHECK-NEXT: %[[RET:.*]] = atomicrmw add ptr %{{.*}}, [[USIZE]] %[[INTPTR]]
+    // CHECK-NEXT: inttoptr [[USIZE]] %[[RET]] to ptr
+    a.fetch_byte_add(v, Relaxed)
+}
+
+// CHECK-LABEL: @atomicptr_swap
+#[no_mangle]
+pub fn atomicptr_swap(a: &AtomicPtr<u8>, ptr: *mut u8) -> *mut u8 {
+    // CHECK-NOT: ptrtoint
+    // CHECK: atomicrmw xchg ptr %{{.*}}, ptr %{{.*}} monotonic
+    // CHECK-NOT: inttoptr
+    a.swap(ptr, Relaxed)
+}