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/bpf_regs.c b/backends/bpf_regs.c
new file mode 100644
index 0000000..1863a16
--- /dev/null
+++ b/backends/bpf_regs.c
@@ -0,0 +1,60 @@
+/* Register names and numbers for BPF DWARF.
+   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 <stdio.h>
+#include <string.h>
+
+#include "bpf.h"
+
+#define BACKEND bpf_
+#include "libebl_CPU.h"
+
+ssize_t
+bpf_register_info (Ebl *ebl __attribute__ ((unused)),
+		   int regno, char *name, size_t namelen,
+		   const char **prefix, const char **setname,
+		   int *bits, int *type)
+{
+  ssize_t len;
+
+  if (name == NULL)
+    return MAX_BPF_REG;
+  if (regno < 0 || regno >= MAX_BPF_REG)
+    return -1;
+
+  *prefix = "";
+  *setname = "integer";
+  *bits = 64;
+  *type = DW_ATE_signed;
+
+  len = snprintf(name, namelen, "r%d", regno);
+  return ((size_t)len < namelen ? len : -1);
+}