[BOLT][AArch64] Add rseq test

[paschalis-mpeis]

No description provided.

[llvmbot]

@llvm/pr-subscribers-bolt

Author: Paschalis Mpeis (paschalis-mpeis)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/174413.diff

1 Files Affected:

• (added) bolt/test/AArch64/rseq.s (+36)

diff --git a/bolt/test/AArch64/rseq.s b/bolt/test/AArch64/rseq.s
new file mode 100644
index 0000000000000..31c3990a48a13
--- /dev/null
+++ b/bolt/test/AArch64/rseq.s
@@ -0,0 +1,36 @@
+## Check that llvm-bolt avoids optimization of functions referenced from
+## __rseq_cs section, i.e. containing critical sections and abort handlers used
+## by restartable sequences in tcmalloc.
+
+# RUN: %clang %cflags %s -o %t -nostdlib -no-pie -Wl,-q
+# RUN: llvm-bolt %t -o %t.bolt --print-cfg 2>&1 | FileCheck %s
+# RUN: %clang %cflags %s -o %t.pie -nostdlib -pie -Wl,-q
+# RUN: llvm-bolt %t.pie -o %t.pie.bolt 2>&1 | FileCheck %s
+
+# CHECK: restartable sequence reference detected in _start
+# CHECK: restartable sequence reference detected in __rseq_abort
+
+  .text
+.reloc 0, R_AARCH64_NONE
+
+  .global _start
+  .type _start, %function
+_start:
+  stp     x29, x30, [sp, #-16]!
+  mov     x29, sp
+.L1:
+  ldp     x29, x30, [sp], #16
+.L2:
+  ret
+  .size _start, .-_start
+
+  .section __rseq_abort, "ax"
+## Signature for rseq abort IP. Unmarked in the symbol table.
+ .long 0xd428bc00 // RSEQ_SIG_CODE, BRK #0x45E0
+.L3:
+  b .L2
+
+.section __rseq_cs, "aw"
+.balign 32
+  .quad .L1
+  .quad .L3

[paschalis-mpeis]

@maksfb tentative PR that adds a restartable sequences test for AArch64.
Do you think the rseq logic checks out?

[maksfb]

@paschalis-mpeis Yes, makes sense to me. Thanks!

[paschalis-mpeis]

Great, thanks. Can you please approve?