Index: libunwind/include/__libunwind_config.h
===================================================================
--- libunwind/include/__libunwind_config.h
+++ libunwind/include/__libunwind_config.h
@@ -36,6 +36,9 @@
 # if defined(__linux__)
 #  define _LIBUNWIND_TARGET_LINUX 1
 # endif
+# if defined(__FreeBSD__)
+#  define _LIBUNWIND_TARGET_FREEBSD 1
+# endif
 # if defined(__i386__)
 #  define _LIBUNWIND_TARGET_I386
 #  define _LIBUNWIND_CONTEXT_SIZE 8
@@ -70,6 +73,8 @@
 #  define _LIBUNWIND_CONTEXT_SIZE 66
 #  if defined(__SEH__)
 #    define _LIBUNWIND_CURSOR_SIZE 164
+#  elif defined(_LIBUNWIND_TARGET_FREEBSD)
+#    define _LIBUNWIND_CURSOR_SIZE 80
 #  else
 #    define _LIBUNWIND_CURSOR_SIZE 78
 #  endif
Index: libunwind/src/UnwindCursor.hpp
===================================================================
--- libunwind/src/UnwindCursor.hpp
+++ libunwind/src/UnwindCursor.hpp
@@ -37,6 +37,18 @@
 #include <sys/uio.h>
 #include <unistd.h>
 #define _LIBUNWIND_CHECK_LINUX_SIGRETURN 1
+#define _LIBUNWIND_CHECK_SIGRETURN 1
+#endif
+
+#if defined(_LIBUNWIND_TARGET_FREEBSD) &&                                      \
+    defined(_LIBUNWIND_TARGET_AARCH64)
+#include <sys/sysctl.h>
+#include <sys/ucontext.h>
+#include <sys/user.h>
+#include <machine/frame.h>
+#include <unistd.h>
+#define _LIBUNWIND_CHECK_FREEBSD_SIGRETURN 1
+#define _LIBUNWIND_CHECK_SIGRETURN 1
 #endif
 
 #include "AddressSpace.hpp"
@@ -981,7 +993,7 @@
   }
 #endif
 
-#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
+#if defined(_LIBUNWIND_CHECK_SIGRETURN)
   bool setInfoForSigReturn() {
     R dummy;
     return setInfoForSigReturn(dummy);
@@ -1008,7 +1020,7 @@
   template <typename Registers> int stepThroughSigReturn(Registers &) {
     return UNW_STEP_END;
   }
-#endif
+#endif  // defined(_LIBUNWIND_CHECK_SIGRETURN)
 
 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
   bool getInfoFromFdeCie(const typename CFI_Parser<A>::FDE_Info &fdeInfo,
@@ -1311,9 +1323,14 @@
   unw_proc_info_t  _info;
   bool             _unwindInfoMissing;
   bool             _isSignalFrame;
-#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
+#if defined(_LIBUNWIND_CHECK_SIGRETURN)
   bool             _isSigReturn = false;
+#if defined(_LIBUNWIND_CHECK_FREEBSD_SIGRETURN)
+  bool             _isSigTrampDetermined = false;
+  pint_t           _sigTrampStart;
+  pint_t           _sigTrampEnd;
 #endif
+#endif // defined(_LIBUNWIND_CHECK_SIGRETURN)
 };
 
 
@@ -2523,7 +2540,7 @@
 
 template <typename A, typename R>
 void UnwindCursor<A, R>::setInfoBasedOnIPRegister(bool isReturnAddress) {
-#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
+#if defined(_LIBUNWIND_CHECK_SIGRETURN)
   _isSigReturn = false;
 #endif
 
@@ -2638,7 +2655,7 @@
   }
 #endif // #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
 
-#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
+#if defined(_LIBUNWIND_CHECK_SIGRETURN)
   if (setInfoForSigReturn())
     return;
 #endif
@@ -2885,6 +2902,63 @@
 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) &&
        // defined(_LIBUNWIND_TARGET_S390X)
 
+#if defined(_LIBUNWIND_CHECK_FREEBSD_SIGRETURN) &&                             \
+    defined(_LIBUNWIND_TARGET_AARCH64)
+template <typename A, typename R>
+bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) {
+  // Look for the sigreturn trampoline.
+  //
+  // https://cgit.freebsd.org/src/tree/sys/arm64/arm64/sigtramp.S
+  const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP));
+
+  if (_isSigTrampDetermined == false) {
+      struct kinfo_sigtramp kst = {0};
+      size_t len = sizeof (kst);
+      int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_SIGTRAMP, getpid() };
+      if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0) {
+	_isSigTrampDetermined = true;
+	_sigTrampStart = reinterpret_cast<pint_t>(kst.ksigtramp_start);
+	_sigTrampEnd = reinterpret_cast<pint_t>(kst.ksigtramp_end);
+      }
+  }
+
+  if (_isSigTrampDetermined == false ||
+    (pc < _sigTrampStart || pc >= _sigTrampEnd))
+	return false;
+
+  _info = {};
+  _info.start_ip = _sigTrampStart;
+  _info.end_ip = _sigTrampEnd;
+  _isSigReturn = true;
+  return true;
+}
+
+template <typename A, typename R>
+int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) {
+  // In the signal trampoline frame, sp points to a sigframe
+  const pint_t kOffsetSpToSigcontext = offsetof(struct sigframe, sf_uc) +
+    offsetof(ucontext_t, uc_mcontext);
+
+  // Offsets from mcontext_t to each register.
+  const pint_t kOffsetGprs = offsetof(struct gpregs, gp_x[0]);
+  const pint_t kOffsetSp = offsetof(struct gpregs, gp_sp);
+  const pint_t kOffsetPc = offsetof(struct gpregs, gp_lr);
+
+  pint_t sigctx = _registers.getSP() + kOffsetSpToSigcontext;
+
+  for (int i = 0; i <= 29; ++i) {
+    uint64_t value = _addressSpace.get64(sigctx + kOffsetGprs +
+                                         static_cast<pint_t>(i * 8));
+    _registers.setRegister(UNW_AARCH64_X0 + i, value);
+  }
+  _registers.setSP(_addressSpace.get64(sigctx + kOffsetSp));
+  _registers.setIP(_addressSpace.get64(sigctx + kOffsetPc));
+  _isSignalFrame = true;
+  return UNW_STEP_SUCCESS;
+}
+#endif // defined(_LIBUNWIND_CHECK_FREEBSD_SIGRETURN) &&
+       // defined(_LIBUNWIND_TARGET_AARCH64)
+
 template <typename A, typename R> int UnwindCursor<A, R>::step(bool stage2) {
   (void)stage2;
   // Bottom of stack is defined is when unwind info cannot be found.
@@ -2893,7 +2967,7 @@
 
   // Use unwinding info to modify register set as if function returned.
   int result;
-#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
+#if defined(_LIBUNWIND_CHECK_SIGRETURN)
   if (_isSigReturn) {
     result = this->stepThroughSigReturn();
   } else