+# elif defined __FreeBSD__
+ case UNW_X86_64_RAX: return &mcontext->mc_rax;
+ case UNW_X86_64_RDX: return &mcontext->mc_rdx;
+ case UNW_X86_64_RCX: return &mcontext->mc_rcx;
+ case UNW_X86_64_RBX: return &mcontext->mc_rbx;
+ case UNW_X86_64_RSI: return &mcontext->mc_rsi;
+ case UNW_X86_64_RDI: return &mcontext->mc_rdi;
+ case UNW_X86_64_RBP: return &mcontext->mc_rbp;
+ case UNW_X86_64_RSP: return &mcontext->mc_rsp;
+ case UNW_X86_64_R8: return &mcontext->mc_r8;
+ case UNW_X86_64_R9: return &mcontext->mc_r9;
+ case UNW_X86_64_R10: return &mcontext->mc_r10;
+ case UNW_X86_64_R11: return &mcontext->mc_r11;
+ case UNW_X86_64_R12: return &mcontext->mc_r12;
+ case UNW_X86_64_R13: return &mcontext->mc_r13;
+ case UNW_X86_64_R14: return &mcontext->mc_r14;
+ case UNW_X86_64_R15: return &mcontext->mc_r15;
+ case UNW_X86_64_RIP: return &mcontext->mc_rip;
+# else
+# error "Unable to get register from ucontext, please add your case"
+# endif