Rollup merge of #128141 - nikic:aarch64-bti, r=DianQK,cuviper

Set branch protection function attributes

Since LLVM 19, it is necessary to set not only module flags, but also function attributes for branch protection on aarch64. See https://github.com/llvm/llvm-project/commit/e15d67cfc2e5775cc79281aa860f3ad3be628f39 for the relevant LLVM change.

Fixes https://github.com/rust-lang/rust/issues/127829.

2 files changed, 55 insertions, 0 deletions

diff --git a/tests/codegen/branch-protection-old-llvm.rs b/tests/codegen/branch-protection-old-llvm.rs
new file mode 100644
index 00000000000..bb3c7a4b70c
--- /dev/null
+++ b/tests/codegen/branch-protection-old-llvm.rs
@@ -0,0 +1,45 @@
+// Test that the correct module flags are emitted with different branch protection flags.
+
+//@ revisions: BTI PACRET LEAF BKEY NONE
+//@ needs-llvm-components: aarch64
+//@ [BTI] compile-flags: -Z branch-protection=bti
+//@ [PACRET] compile-flags: -Z branch-protection=pac-ret
+//@ [LEAF] compile-flags: -Z branch-protection=pac-ret,leaf
+//@ [BKEY] compile-flags: -Z branch-protection=pac-ret,b-key
+//@ compile-flags: --target aarch64-unknown-linux-gnu
+//@ ignore-llvm-version: 19 - 99
+
+#![crate_type = "lib"]
+#![feature(no_core, lang_items)]
+#![no_core]
+
+#[lang = "sized"]
+trait Sized {}
+
+// A basic test function.
+pub fn test() {}
+
+// BTI: !"branch-target-enforcement", i32 1
+// BTI: !"sign-return-address", i32 0
+// BTI: !"sign-return-address-all", i32 0
+// BTI: !"sign-return-address-with-bkey", i32 0
+
+// PACRET: !"branch-target-enforcement", i32 0
+// PACRET: !"sign-return-address", i32 1
+// PACRET: !"sign-return-address-all", i32 0
+// PACRET: !"sign-return-address-with-bkey", i32 0
+
+// LEAF: !"branch-target-enforcement", i32 0
+// LEAF: !"sign-return-address", i32 1
+// LEAF: !"sign-return-address-all", i32 1
+// LEAF: !"sign-return-address-with-bkey", i32 0
+
+// BKEY: !"branch-target-enforcement", i32 0
+// BKEY: !"sign-return-address", i32 1
+// BKEY: !"sign-return-address-all", i32 0
+// BKEY: !"sign-return-address-with-bkey", i32 1
+
+// NONE-NOT: branch-target-enforcement
+// NONE-NOT: sign-return-address
+// NONE-NOT: sign-return-address-all
+// NONE-NOT: sign-return-address-with-bkey
diff --git a/tests/codegen/branch-protection.rs b/tests/codegen/branch-protection.rs
index a29ec67d578..2f5ff9e98c2 100644
--- a/tests/codegen/branch-protection.rs
+++ b/tests/codegen/branch-protection.rs
@@ -7,6 +7,7 @@
 //@ [LEAF] compile-flags: -Z branch-protection=pac-ret,leaf
 //@ [BKEY] compile-flags: -Z branch-protection=pac-ret,b-key
 //@ compile-flags: --target aarch64-unknown-linux-gnu
+//@ min-llvm-version: 19
 
 #![crate_type = "lib"]
 #![feature(no_core, lang_items)]
@@ -16,23 +17,32 @@
 trait Sized {}
 
 // A basic test function.
+// CHECK: @test(){{.*}} [[ATTR:#[0-9]+]] {
+#[no_mangle]
 pub fn test() {}
 
+// BTI: attributes [[ATTR]] = {{.*}} "branch-target-enforcement"
 // BTI: !"branch-target-enforcement", i32 1
 // BTI: !"sign-return-address", i32 0
 // BTI: !"sign-return-address-all", i32 0
 // BTI: !"sign-return-address-with-bkey", i32 0
 
+// PACRET: attributes [[ATTR]] = {{.*}} "sign-return-address"="non-leaf"
+// PACRET-SAME: "sign-return-address-key"="a_key"
 // PACRET: !"branch-target-enforcement", i32 0
 // PACRET: !"sign-return-address", i32 1
 // PACRET: !"sign-return-address-all", i32 0
 // PACRET: !"sign-return-address-with-bkey", i32 0
 
+// LEAF: attributes [[ATTR]] = {{.*}} "sign-return-address"="all"
+// LEAF-SAME: "sign-return-address-key"="a_key"
 // LEAF: !"branch-target-enforcement", i32 0
 // LEAF: !"sign-return-address", i32 1
 // LEAF: !"sign-return-address-all", i32 1
 // LEAF: !"sign-return-address-with-bkey", i32 0
 
+// BKEY: attributes [[ATTR]] = {{.*}} "sign-return-address"="non-leaf"
+// BKEY-SAME: "sign-return-address-key"="b_key"
 // BKEY: !"branch-target-enforcement", i32 0
 // BKEY: !"sign-return-address", i32 1
 // BKEY: !"sign-return-address-all", i32 0