[libunwind] Ensure zaDisable() is called in jumpto/returnto (NFC)

[MacDue]

This is an NFC for now, as the SME checks for macOS platforms are not implemented, so zaDisable() is a no-op, but both paths for resuming from an exception should disable ZA.

This is a fixup for a recent change in #165066.

[llvmbot]

@llvm/pr-subscribers-libunwind

Author: Benjamin Maxwell (MacDue)

Changes

This is an NFC for now, as the SME checks for macOS platforms are not implemented, so zaDisable() is a no-op, but both paths for resuming from an exception should disable ZA.

This is a fixup for a recent change in #165066.

---

Full diff: https://github.com/llvm/llvm-project/pull/167674.diff

1 Files Affected:

• (modified) libunwind/src/Registers.hpp (+5-8)

diff --git a/libunwind/src/Registers.hpp b/libunwind/src/Registers.hpp
index 28649fafb23d5..45a2b0921ea3b 100644
--- a/libunwind/src/Registers.hpp
+++ b/libunwind/src/Registers.hpp
@@ -1862,16 +1862,13 @@ class _LIBUNWIND_HIDDEN Registers_arm64 {
   v128        getVectorRegister(int num) const;
   void        setVectorRegister(int num, v128 value);
   static const char *getRegisterName(int num);
+  void        jumpto(unsigned walkedFrames = 0) {
+    zaDisable();
+    __libunwind_Registers_arm64_jumpto(this, walkedFrames);
+  }
 #ifdef _LIBUNWIND_TRACE_RET_INJECT
   _LIBUNWIND_TRACE_NO_INLINE
-    void      returnto(unsigned walkedFrames) {
-      __libunwind_Registers_arm64_jumpto(this, walkedFrames);
-    }
-#else
-  void        jumpto() {
-      zaDisable();
-      __libunwind_Registers_arm64_jumpto(this, 0);
-  }
+  void        returnto(unsigned walkedFrames) { jumpto(walkedFrames); }
 #endif
   static constexpr int lastDwarfRegNum() {
     return _LIBUNWIND_HIGHEST_DWARF_REGISTER_ARM64;

[medismailben]

the SME checks for macOS platforms are not implemented

Yeah, that's why I didn't call in in returnto but since it's a no-op it should be fine.