Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/backends/aarch64_initreg.c b/backends/aarch64_initreg.c
new file mode 100644
index 0000000..daf6f37
--- /dev/null
+++ b/backends/aarch64_initreg.c
@@ -0,0 +1,92 @@
+/* Fetch live process registers from TID.
+   Copyright (C) 2013, 2014 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "system.h"
+#include <assert.h>
+#if defined(__aarch64__) && defined(__linux__)
+# include <linux/uio.h>
+# include <sys/user.h>
+# include <sys/ptrace.h>
+/* Deal with old glibc defining user_pt_regs instead of user_regs_struct.  */
+# ifndef HAVE_SYS_USER_REGS
+#  define user_regs_struct user_pt_regs
+#  define user_fpsimd_struct user_fpsimd_state
+# endif
+#endif
+
+#define BACKEND aarch64_
+#include "libebl_CPU.h"
+
+bool
+aarch64_set_initial_registers_tid (pid_t tid __attribute__ ((unused)),
+			  ebl_tid_registers_t *setfunc __attribute__ ((unused)),
+				void *arg __attribute__ ((unused)))
+{
+#if !defined(__aarch64__) || !defined(__linux__)
+  return false;
+#else /* __aarch64__ */
+
+  /* General registers.  */
+  struct user_regs_struct gregs;
+  struct iovec iovec;
+  iovec.iov_base = &gregs;
+  iovec.iov_len = sizeof (gregs);
+  if (ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iovec) != 0)
+    return false;
+
+  /* X0..X30 plus SP.  */
+  if (! setfunc (0, 32, (Dwarf_Word *) &gregs.regs[0], arg))
+    return false;
+
+  /* PC.  */
+  if (! setfunc (-1, 1, (Dwarf_Word *) &gregs.pc, arg))
+    return false;
+
+  /* ELR cannot be found.  */
+
+  /* FP registers (only 64bits are used).  */
+  struct user_fpsimd_struct fregs;
+  iovec.iov_base = &fregs;
+  iovec.iov_len = sizeof (fregs);
+  if (ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET, &iovec) != 0)
+    return false;
+
+  Dwarf_Word dwarf_fregs[32];
+  for (int r = 0; r < 32; r++)
+    dwarf_fregs[r] = fregs.vregs[r] & 0xFFFFFFFF;
+
+  if (! setfunc (64, 32, dwarf_fregs, arg))
+    return false;
+
+  return true;
+#endif /* __aarch64__ */
+}