$NetBSD$

--- src/x86_64/Gos-netbsd.c.orig	2018-09-05 10:31:53.514510455 +0000
+++ src/x86_64/Gos-netbsd.c
@@ -0,0 +1,158 @@
+/* libunwind - a platform-independent unwind library
+   Copyright (C) 2002-2003 Hewlett-Packard Co
+        Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
+
+   Modified for x86_64 by Max Asbock <masbock@us.ibm.com>
+
+This file is part of libunwind.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
+
+#include "unwind_i.h"
+#include "ucontext_i.h"
+
+#include <sys/syscall.h>
+
+HIDDEN void
+tdep_fetch_frame (struct dwarf_cursor *dw, unw_word_t ip, int need_unwind_info)
+{
+  struct cursor *c = (struct cursor *) dw;
+  assert(! need_unwind_info || dw->pi_valid);
+  assert(! need_unwind_info || dw->pi.unwind_info);
+  if (dw->pi_valid
+      && dw->pi.unwind_info
+      && ((struct dwarf_cie_info *) dw->pi.unwind_info)->signal_frame)
+    c->sigcontext_format = X86_64_SCF_LINUX_RT_SIGFRAME;
+  else
+    c->sigcontext_format = X86_64_SCF_NONE;
+
+  Debug(5, "fetch frame ip=0x%lx cfa=0x%lx format=%d\n",
+        dw->ip, dw->cfa, c->sigcontext_format);
+}
+
+HIDDEN int
+tdep_cache_frame (struct dwarf_cursor *dw)
+{
+  struct cursor *c = (struct cursor *) dw;
+
+  Debug(5, "cache frame ip=0x%lx cfa=0x%lx format=%d\n",
+        dw->ip, dw->cfa, c->sigcontext_format);
+  return c->sigcontext_format;
+}
+
+HIDDEN void
+tdep_reuse_frame (struct dwarf_cursor *dw, int frame)
+{
+  struct cursor *c = (struct cursor *) dw;
+  c->sigcontext_format = frame;
+  if (c->sigcontext_format == X86_64_SCF_LINUX_RT_SIGFRAME)
+  {
+    c->frame_info.frame_type = UNW_X86_64_FRAME_SIGRETURN;
+    /* Offset from cfa to ucontext_t in signal frame.  */
+    c->frame_info.cfa_reg_offset = 0;
+    c->sigcontext_addr = dw->cfa;
+  }
+
+  Debug(5, "reuse frame ip=0x%lx cfa=0x%lx format=%d addr=0x%lx offset=%+d\n",
+        dw->ip, dw->cfa, c->sigcontext_format, c->sigcontext_addr,
+        (c->sigcontext_format == X86_64_SCF_LINUX_RT_SIGFRAME
+         ? c->frame_info.cfa_reg_offset : 0));
+}
+
+int
+unw_is_signal_frame (unw_cursor_t *cursor)
+{
+  struct cursor *c = (struct cursor *) cursor;
+  return c->sigcontext_format != X86_64_SCF_NONE;
+}
+
+HIDDEN int
+x86_64_handle_signal_frame (unw_cursor_t *cursor)
+{
+#if UNW_DEBUG /* To silence compiler warnings */
+  /* Should not get here because we now use kernel-provided dwarf
+     information for the signal trampoline and dwarf_step() works.
+     Hence unw_step() should never call this function. Maybe
+     restore old non-dwarf signal handling here, but then the
+     gating on unw_is_signal_frame() needs to be removed. */
+  struct cursor *c = (struct cursor *) cursor;
+  Debug(1, "old format signal frame? format=%d addr=0x%lx cfa=0x%lx\n",
+        c->sigcontext_format, c->sigcontext_addr, c->dwarf.cfa);
+#endif
+  return -UNW_EBADFRAME;
+}
+
+#ifndef UNW_REMOTE_ONLY
+HIDDEN void *
+x86_64_r_uc_addr (ucontext_t *uc, int reg)
+{
+  /* NOTE: common_init() in init.h inlines these for fast path access. */
+  void *addr;
+
+  switch (reg)
+    {
+    case UNW_X86_64_R8: addr = &uc->uc_mcontext.__gregs[_REG_R8]; break;
+    case UNW_X86_64_R9: addr = &uc->uc_mcontext.__gregs[_REG_R9]; break;
+    case UNW_X86_64_R10: addr = &uc->uc_mcontext.__gregs[_REG_R10]; break;
+    case UNW_X86_64_R11: addr = &uc->uc_mcontext.__gregs[_REG_R11]; break;
+    case UNW_X86_64_R12: addr = &uc->uc_mcontext.__gregs[_REG_R12]; break;
+    case UNW_X86_64_R13: addr = &uc->uc_mcontext.__gregs[_REG_R13]; break;
+    case UNW_X86_64_R14: addr = &uc->uc_mcontext.__gregs[_REG_R14]; break;
+    case UNW_X86_64_R15: addr = &uc->uc_mcontext.__gregs[_REG_R15]; break;
+    case UNW_X86_64_RDI: addr = &uc->uc_mcontext.__gregs[_REG_RDI]; break;
+    case UNW_X86_64_RSI: addr = &uc->uc_mcontext.__gregs[_REG_RSI]; break;
+    case UNW_X86_64_RBP: addr = &uc->uc_mcontext.__gregs[_REG_RBP]; break;
+    case UNW_X86_64_RBX: addr = &uc->uc_mcontext.__gregs[_REG_RBX]; break;
+    case UNW_X86_64_RDX: addr = &uc->uc_mcontext.__gregs[_REG_RDX]; break;
+    case UNW_X86_64_RAX: addr = &uc->uc_mcontext.__gregs[_REG_RAX]; break;
+    case UNW_X86_64_RCX: addr = &uc->uc_mcontext.__gregs[_REG_RCX]; break;
+    case UNW_X86_64_RSP: addr = &uc->uc_mcontext.__gregs[_REG_RSP]; break;
+    case UNW_X86_64_RIP: addr = &uc->uc_mcontext.__gregs[_REG_RIP]; break;
+
+    default:
+      addr = NULL;
+    }
+  return addr;
+}
+
+/* sigreturn() is a no-op on x86_64 glibc.  */
+HIDDEN NORETURN void
+x86_64_sigreturn (unw_cursor_t *cursor)
+{
+  struct cursor *c = (struct cursor *) cursor;
+  struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr;
+  mcontext_t *sc_mcontext = &((ucontext_t*)sc)->uc_mcontext;
+  /* Copy in saved uc - all preserved regs are at the start of sigcontext */
+  memcpy(sc_mcontext, &c->uc->uc_mcontext,
+         DWARF_NUM_PRESERVED_REGS * sizeof(unw_word_t));
+
+  Debug (8, "resuming at ip=%llx via sigreturn(%p)\n",
+             (unsigned long long) c->dwarf.ip, sc);
+#if 0
+  __asm__ __volatile__ ("mov %0, %%rsp;"
+                        "mov %1, %%rax;"
+                        "syscall"
+                        :: "r"(sc), "i"(SYS_rt_sigreturn)
+                        : "memory");
+#endif
+  abort();
+}
+
+#endif
