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/alpha_symbol.c b/backends/alpha_symbol.c
new file mode 100644
index 0000000..657d9ee
--- /dev/null
+++ b/backends/alpha_symbol.c
@@ -0,0 +1,156 @@
+/* Alpha specific symbolic name handling.
+   Copyright (C) 2002-2011 Red Hat, Inc.
+   This file is part of elfutils.
+   Written by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   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 <elf.h>
+#include <stddef.h>
+#include <string.h>
+
+#define BACKEND		alpha_
+#include "libebl_CPU.h"
+
+
+const char *
+alpha_dynamic_tag_name (int64_t tag, char *buf __attribute__ ((unused)),
+			size_t len __attribute__ ((unused)))
+{
+  switch (tag)
+    {
+    case DT_ALPHA_PLTRO:
+      return "ALPHA_PLTRO";
+    default:
+      break;
+    }
+  return NULL;
+}
+
+bool
+alpha_dynamic_tag_check (int64_t tag)
+{
+  return tag == DT_ALPHA_PLTRO;
+}
+
+/* Check for the simple reloc types.  */
+Elf_Type
+alpha_reloc_simple_type (Ebl *ebl __attribute__ ((unused)), int type)
+{
+  switch (type)
+    {
+    case R_ALPHA_REFLONG:
+      return ELF_T_WORD;
+    case R_ALPHA_REFQUAD:
+      return ELF_T_XWORD;
+    default:
+      return ELF_T_NUM;
+    }
+}
+
+
+/* Check whether SHF_MASKPROC flags are valid.  */
+bool
+alpha_machine_section_flag_check (GElf_Xword sh_flags)
+{
+  return (sh_flags &~ (SHF_ALPHA_GPREL)) == 0;
+}
+
+bool
+alpha_check_special_section (Ebl *ebl,
+			     int ndx __attribute__ ((unused)),
+			     const GElf_Shdr *shdr,
+			     const char *sname __attribute__ ((unused)))
+{
+  if ((shdr->sh_flags
+       & (SHF_WRITE | SHF_EXECINSTR)) == (SHF_WRITE | SHF_EXECINSTR)
+      && shdr->sh_addr != 0)
+    {
+      /* This is ordinarily flagged, but is valid for an old-style PLT.
+
+	 Look for the SHT_DYNAMIC section and the DT_PLTGOT tag in it.
+	 Its d_ptr should match the .plt section's sh_addr.  */
+
+      Elf_Scn *scn = NULL;
+      while ((scn = elf_nextscn (ebl->elf, scn)) != NULL)
+	{
+	  GElf_Shdr scn_shdr;
+	  if (likely (gelf_getshdr (scn, &scn_shdr) != NULL)
+	      && scn_shdr.sh_type == SHT_DYNAMIC
+	      && scn_shdr.sh_entsize != 0)
+	    {
+	      GElf_Addr pltgot = 0;
+	      Elf_Data *data = elf_getdata (scn, NULL);
+	      if (data != NULL)
+		for (size_t i = 0; i < data->d_size / scn_shdr.sh_entsize; ++i)
+		  {
+		    GElf_Dyn dyn;
+		    if (unlikely (gelf_getdyn (data, i, &dyn) == NULL))
+		      break;
+		    if (dyn.d_tag == DT_PLTGOT)
+		      pltgot = dyn.d_un.d_ptr;
+		    else if (dyn.d_tag == DT_ALPHA_PLTRO && dyn.d_un.d_val != 0)
+		      return false; /* This PLT should not be writable.  */
+		  }
+	      return pltgot == shdr->sh_addr;
+	    }
+	}
+    }
+
+  return false;
+}
+
+/* Check whether given symbol's st_value and st_size are OK despite failing
+   normal checks.  */
+bool
+alpha_check_special_symbol (Elf *elf __attribute__ ((unused)),
+			    GElf_Ehdr *ehdr __attribute__ ((unused)),
+			    const GElf_Sym *sym __attribute__ ((unused)),
+			    const char *name,
+			    const GElf_Shdr *destshdr __attribute__ ((unused)))
+{
+  if (name == NULL)
+    return false;
+
+  if (strcmp (name, "_GLOBAL_OFFSET_TABLE_") == 0)
+    /* On Alpha any place in the section is valid.  */
+    return true;
+
+  return false;
+}
+
+/* Check whether only valid bits are set on the st_other symbol flag.
+   Standard ST_VISIBILITY have already been masked off.  */
+bool
+alpha_check_st_other_bits (unsigned char st_other)
+{
+  return ((((st_other & STO_ALPHA_STD_GPLOAD) == STO_ALPHA_NOPV)
+	   || ((st_other & STO_ALPHA_STD_GPLOAD) == STO_ALPHA_STD_GPLOAD))
+	  && (st_other &~ STO_ALPHA_STD_GPLOAD) == 0);
+}