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diff --git a/libdw/encoded-value.h b/libdw/encoded-value.h
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+/* DW_EH_PE_* support for libdw unwinder.
+ Copyright (C) 2009-2010 Red Hat, Inc.
+ This file is part of Red Hat elfutils.
+
+ Red Hat elfutils is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by the
+ Free Software Foundation; version 2 of the License.
+
+ Red Hat 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 a copy of the GNU General Public License along
+ with Red Hat elfutils; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
+
+ In addition, as a special exception, Red Hat, Inc. gives You the
+ additional right to link the code of Red Hat elfutils with code licensed
+ under any Open Source Initiative certified open source license
+ (http://www.opensource.org/licenses/index.php) which requires the
+ distribution of source code with any binary distribution and to
+ distribute linked combinations of the two. Non-GPL Code permitted under
+ this exception must only link to the code of Red Hat elfutils through
+ those well defined interfaces identified in the file named EXCEPTION
+ found in the source code files (the "Approved Interfaces"). The files
+ of Non-GPL Code may instantiate templates or use macros or inline
+ functions from the Approved Interfaces without causing the resulting
+ work to be covered by the GNU General Public License. Only Red Hat,
+ Inc. may make changes or additions to the list of Approved Interfaces.
+ Red Hat's grant of this exception is conditioned upon your not adding
+ any new exceptions. If you wish to add a new Approved Interface or
+ exception, please contact Red Hat. You must obey the GNU General Public
+ License in all respects for all of the Red Hat elfutils code and other
+ code used in conjunction with Red Hat elfutils except the Non-GPL Code
+ covered by this exception. If you modify this file, you may extend this
+ exception to your version of the file, but you are not obligated to do
+ so. If you do not wish to provide this exception without modification,
+ you must delete this exception statement from your version and license
+ this file solely under the GPL without exception.
+
+ Red Hat elfutils is an included package of the Open Invention Network.
+ An included package of the Open Invention Network is a package for which
+ Open Invention Network licensees cross-license their patents. No patent
+ license is granted, either expressly or impliedly, by designation as an
+ included package. Should you wish to participate in the Open Invention
+ Network licensing program, please visit www.openinventionnetwork.com
+ <http://www.openinventionnetwork.com>. */
+
+#ifndef _ENCODED_VALUE_H
+#define _ENCODED_VALUE_H 1
+
+#include <dwarf.h>
+#include <stdlib.h>
+#include "libdwP.h"
+
+
+static size_t __attribute__ ((unused))
+encoded_value_size (const Elf_Data *data, const unsigned char e_ident[],
+ uint8_t encoding, const uint8_t *p)
+{
+ if (encoding == DW_EH_PE_omit)
+ return 0;
+
+ switch (encoding & 0x07)
+ {
+ case DW_EH_PE_udata2:
+ return 2;
+ case DW_EH_PE_udata4:
+ return 4;
+ case DW_EH_PE_udata8:
+ return 8;
+
+ case DW_EH_PE_absptr:
+ return e_ident[EI_CLASS] == ELFCLASS32 ? 4 : 8;
+
+ case DW_EH_PE_uleb128:
+ if (p != NULL)
+ {
+ const uint8_t *end = p;
+ while (end < (uint8_t *) data->d_buf + data->d_size)
+ if (*end++ & 0x80u)
+ return end - p;
+ }
+
+ default:
+ abort ();
+ return 0;
+ }
+}
+
+static inline int __attribute__ ((unused))
+__libdw_cfi_read_address_inc (const Dwarf_CFI *cache,
+ const unsigned char **addrp,
+ int width, Dwarf_Addr *ret)
+{
+ width = width ?: cache->e_ident[EI_CLASS] == ELFCLASS32 ? 4 : 8;
+
+ if (cache->dbg != NULL)
+ return __libdw_read_address_inc (cache->dbg, IDX_debug_frame,
+ addrp, width, ret);
+
+ /* Only .debug_frame might have relocation to consider.
+ Read plain values from .eh_frame data. */
+
+ if (width == 4)
+ *ret = read_4ubyte_unaligned_inc (cache, *addrp);
+ else
+ *ret = read_8ubyte_unaligned_inc (cache, *addrp);
+ return 0;
+}
+
+static bool __attribute__ ((unused))
+read_encoded_value (const Dwarf_CFI *cache, uint8_t encoding, const uint8_t **p,
+ Dwarf_Addr *result)
+{
+ *result = 0;
+ switch (encoding & 0x70)
+ {
+ case DW_EH_PE_absptr:
+ break;
+ case DW_EH_PE_pcrel:
+ *result = (cache->frame_vaddr
+ + (*p - (const uint8_t *) cache->data->d.d_buf));
+ break;
+ case DW_EH_PE_textrel:
+ // ia64: segrel
+ *result = cache->textrel;
+ break;
+ case DW_EH_PE_datarel:
+ // i386: GOTOFF
+ // ia64: gprel
+ *result = cache->datarel;
+ break;
+ case DW_EH_PE_funcrel: /* XXX */
+ break;
+ case DW_EH_PE_aligned:
+ {
+ const size_t size = encoded_value_size (&cache->data->d, cache->e_ident,
+ encoding, *p);
+ size_t align = ((cache->frame_vaddr
+ + (*p - (const uint8_t *) cache->data->d.d_buf))
+ & (size - 1));
+ if (align != 0)
+ *p += size - align;
+ break;
+ }
+
+ default:
+ abort ();
+ }
+
+ Dwarf_Addr value;
+ switch (encoding & 0x0f)
+ {
+ case DW_EH_PE_udata2:
+ value = read_2ubyte_unaligned_inc (cache, *p);
+ break;
+
+ case DW_EH_PE_sdata2:
+ value = read_2sbyte_unaligned_inc (cache, *p);
+ break;
+
+ case DW_EH_PE_udata4:
+ if (__libdw_cfi_read_address_inc (cache, p, 4, &value))
+ return true;
+ break;
+
+ case DW_EH_PE_sdata4:
+ if (__libdw_cfi_read_address_inc (cache, p, 4, &value))
+ return true;
+ value = (Dwarf_Sword) (Elf32_Sword) value; /* Sign-extend. */
+ break;
+
+ case DW_EH_PE_udata8:
+ case DW_EH_PE_sdata8:
+ if (__libdw_cfi_read_address_inc (cache, p, 8, &value))
+ return true;
+ break;
+
+ case DW_EH_PE_absptr:
+ if (__libdw_cfi_read_address_inc (cache, p, 0, &value))
+ return true;
+ break;
+
+ case DW_EH_PE_uleb128:
+ get_uleb128 (value, *p);
+ break;
+
+ case DW_EH_PE_sleb128:
+ get_sleb128 (value, *p);
+ break;
+
+ default:
+ abort ();
+ }
+
+ *result += value;
+
+ if (encoding & DW_EH_PE_indirect)
+ {
+ if (unlikely (*result < cache->frame_vaddr))
+ return true;
+ *result -= cache->frame_vaddr;
+ if (unlikely (*result > (cache->data->d.d_size
+ - encoded_value_size (NULL, cache->e_ident,
+ DW_EH_PE_absptr, NULL))))
+ return true;
+ const uint8_t *ptr = cache->data->d.d_buf + *result;
+ return __libdw_cfi_read_address_inc (cache, &ptr, 0, result);
+ }
+
+ return false;
+}
+
+#endif /* encoded-value.h */
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