Rollup merge of #132259 - mrkajetanp:branch-protection-pauth-lr, r=davidtwco

rustc_codegen_llvm: Add a new 'pc' option to branch-protection

Add a new 'pc' option to -Z branch-protection for aarch64 that enables the use of PC as a diversifier in PAC branch protection code.

When the pauth-lr target feature is enabled in combination with -Z branch-protection=pac-ret,pc, the new 9.5-a instructions (pacibsppc, retaasppc, etc) will be generated.

1 files changed, 41 insertions, 1 deletions

diff --git a/tests/codegen/branch-protection.rs b/tests/codegen/branch-protection.rs
index 2f5ff9e98c2..945bad05625 100644
--- a/tests/codegen/branch-protection.rs
+++ b/tests/codegen/branch-protection.rs
@@ -1,11 +1,15 @@
 // Test that the correct module flags are emitted with different branch protection flags.
 
-//@ revisions: BTI PACRET LEAF BKEY NONE
+//@ revisions: BTI PACRET LEAF BKEY PAUTHLR PAUTHLR_BKEY PAUTHLR_LEAF PAUTHLR_BTI 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
+//@ [PAUTHLR] compile-flags: -Z branch-protection=pac-ret,pc
+//@ [PAUTHLR_BKEY] compile-flags: -Z branch-protection=pac-ret,pc,b-key
+//@ [PAUTHLR_LEAF] compile-flags: -Z branch-protection=pac-ret,pc,leaf
+//@ [PAUTHLR_BTI] compile-flags: -Z branch-protection=bti,pac-ret,pc
 //@ compile-flags: --target aarch64-unknown-linux-gnu
 //@ min-llvm-version: 19
 
@@ -24,6 +28,7 @@ pub fn test() {}
 // BTI: attributes [[ATTR]] = {{.*}} "branch-target-enforcement"
 // BTI: !"branch-target-enforcement", i32 1
 // BTI: !"sign-return-address", i32 0
+// BTI: !"branch-protection-pauth-lr", i32 0
 // BTI: !"sign-return-address-all", i32 0
 // BTI: !"sign-return-address-with-bkey", i32 0
 
@@ -31,6 +36,7 @@ pub fn test() {}
 // PACRET-SAME: "sign-return-address-key"="a_key"
 // PACRET: !"branch-target-enforcement", i32 0
 // PACRET: !"sign-return-address", i32 1
+// PACRET: !"branch-protection-pauth-lr", i32 0
 // PACRET: !"sign-return-address-all", i32 0
 // PACRET: !"sign-return-address-with-bkey", i32 0
 
@@ -38,6 +44,7 @@ pub fn test() {}
 // LEAF-SAME: "sign-return-address-key"="a_key"
 // LEAF: !"branch-target-enforcement", i32 0
 // LEAF: !"sign-return-address", i32 1
+// LEAF: !"branch-protection-pauth-lr", i32 0
 // LEAF: !"sign-return-address-all", i32 1
 // LEAF: !"sign-return-address-with-bkey", i32 0
 
@@ -45,9 +52,42 @@ pub fn test() {}
 // BKEY-SAME: "sign-return-address-key"="b_key"
 // BKEY: !"branch-target-enforcement", i32 0
 // BKEY: !"sign-return-address", i32 1
+// BKEY: !"branch-protection-pauth-lr", i32 0
 // BKEY: !"sign-return-address-all", i32 0
 // BKEY: !"sign-return-address-with-bkey", i32 1
 
+// PAUTHLR: attributes [[ATTR]] = {{.*}} "sign-return-address"="non-leaf"
+// PAUTHLR-SAME: "sign-return-address-key"="a_key"
+// PAUTHLR: !"branch-target-enforcement", i32 0
+// PAUTHLR: !"sign-return-address", i32 1
+// PAUTHLR: !"branch-protection-pauth-lr", i32 1
+// PAUTHLR: !"sign-return-address-all", i32 0
+// PAUTHLR: !"sign-return-address-with-bkey", i32 0
+
+// PAUTHLR_BKEY: attributes [[ATTR]] = {{.*}} "sign-return-address"="non-leaf"
+// PAUTHLR_BKEY-SAME: "sign-return-address-key"="b_key"
+// PAUTHLR_BKEY: !"branch-target-enforcement", i32 0
+// PAUTHLR_BKEY: !"sign-return-address", i32 1
+// PAUTHLR_BKEY: !"branch-protection-pauth-lr", i32 1
+// PAUTHLR_BKEY: !"sign-return-address-all", i32 0
+// PAUTHLR_BKEY: !"sign-return-address-with-bkey", i32 1
+
+// PAUTHLR_LEAF: attributes [[ATTR]] = {{.*}} "sign-return-address"="all"
+// PAUTHLR_LEAF-SAME: "sign-return-address-key"="a_key"
+// PAUTHLR_LEAF: !"branch-target-enforcement", i32 0
+// PAUTHLR_LEAF: !"sign-return-address", i32 1
+// PAUTHLR_LEAF: !"branch-protection-pauth-lr", i32 1
+// PAUTHLR_LEAF: !"sign-return-address-all", i32 1
+// PAUTHLR_LEAF: !"sign-return-address-with-bkey", i32 0
+
+// PAUTHLR_BTI: attributes [[ATTR]] = {{.*}} "sign-return-address"="non-leaf"
+// PAUTHLR_BTI-SAME: "sign-return-address-key"="a_key"
+// PAUTHLR_BTI: !"branch-target-enforcement", i32 1
+// PAUTHLR_BTI: !"sign-return-address", i32 1
+// PAUTHLR_BTI: !"branch-protection-pauth-lr", i32 1
+// PAUTHLR_BTI: !"sign-return-address-all", i32 0
+// PAUTHLR_BTI: !"sign-return-address-with-bkey", i32 0
+
 // NONE-NOT: branch-target-enforcement
 // NONE-NOT: sign-return-address
 // NONE-NOT: sign-return-address-all