diff --git a/libdw/cie.c b/libdw/cie.c
new file mode 100644
index 0000000..1b0aae7
--- /dev/null
+++ b/libdw/cie.c
@@ -0,0 +1,196 @@
+/* CIE reading.
+   Copyright (C) 2009-2010 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 "cfi.h"
+#include "encoded-value.h"
+#include <assert.h>
+#include <search.h>
+#include <stdlib.h>
+
+
+static int
+compare_cie (const void *a, const void *b)
+{
+  const struct dwarf_cie *cie1 = a;
+  const struct dwarf_cie *cie2 = b;
+  if (cie1->offset < cie2->offset)
+    return -1;
+  if (cie1->offset > cie2->offset)
+    return 1;
+  return 0;
+}
+
+/* There is no CIE at OFFSET in the tree.  Add it.  */
+static struct dwarf_cie *
+intern_new_cie (Dwarf_CFI *cache, Dwarf_Off offset, const Dwarf_CIE *info)
+{
+  struct dwarf_cie *cie = malloc (sizeof (struct dwarf_cie));
+  if (cie == NULL)
+    {
+      __libdw_seterrno (DWARF_E_NOMEM);
+      return NULL;
+    }
+
+  cie->offset = offset;
+  cie->code_alignment_factor = info->code_alignment_factor;
+  cie->data_alignment_factor = info->data_alignment_factor;
+  cie->return_address_register = info->return_address_register;
+
+  cie->fde_augmentation_data_size = 0;
+  cie->sized_augmentation_data = false;
+  cie->signal_frame = false;
+
+  cie->fde_encoding = DW_EH_PE_absptr;
+  cie->lsda_encoding = DW_EH_PE_omit;
+
+  /* Grok the augmentation string and its data.  */
+  const uint8_t *data = info->augmentation_data;
+  for (const char *ap = info->augmentation; *ap != '\0'; ++ap)
+    {
+      uint8_t encoding;
+      switch (*ap)
+	{
+	case 'z':
+	  cie->sized_augmentation_data = true;
+	  continue;
+
+	case 'S':
+	  cie->signal_frame = true;
+	  continue;
+
+	case 'L':		/* LSDA pointer encoding byte.  */
+	  cie->lsda_encoding = *data++;
+	  if (!cie->sized_augmentation_data)
+	    cie->fde_augmentation_data_size
+	      += encoded_value_size (&cache->data->d, cache->e_ident,
+				     cie->lsda_encoding, NULL);
+	  continue;
+
+	case 'R':		/* FDE address encoding byte.  */
+	  cie->fde_encoding = *data++;
+	  continue;
+
+	case 'P':		/* Skip personality routine.  */
+	  encoding = *data++;
+	  data += encoded_value_size (&cache->data->d, cache->e_ident,
+				      encoding, data);
+	  continue;
+
+	default:
+	  /* Unknown augmentation string.  If we have 'z' we can ignore it,
+	     otherwise we must bail out.  */
+	  if (cie->sized_augmentation_data)
+	    continue;
+	}
+      /* We only get here when we need to bail out.  */
+      break;
+    }
+
+  if ((cie->fde_encoding & 0x0f) == DW_EH_PE_absptr)
+    {
+      /* Canonicalize encoding to a specific size.  */
+      assert (DW_EH_PE_absptr == 0);
+
+      /* XXX should get from dwarf_next_cfi with v4 header.  */
+      uint_fast8_t address_size
+	= cache->e_ident[EI_CLASS] == ELFCLASS32 ? 4 : 8;
+      switch (address_size)
+	{
+	case 8:
+	  cie->fde_encoding |= DW_EH_PE_udata8;
+	  break;
+	case 4:
+	  cie->fde_encoding |= DW_EH_PE_udata4;
+	  break;
+	default:
+	  free (cie);
+	  __libdw_seterrno (DWARF_E_INVALID_DWARF);
+	  return NULL;
+	}
+    }
+
+  /* Save the initial instructions to be played out into initial state.  */
+  cie->initial_instructions = info->initial_instructions;
+  cie->initial_instructions_end = info->initial_instructions_end;
+  cie->initial_state = NULL;
+
+  /* Add the new entry to the search tree.  */
+  if (tsearch (cie, &cache->cie_tree, &compare_cie) == NULL)
+    {
+      free (cie);
+      __libdw_seterrno (DWARF_E_NOMEM);
+      return NULL;
+    }
+
+  return cie;
+}
+
+/* Look up a CIE_pointer for random access.  */
+struct dwarf_cie *
+internal_function
+__libdw_find_cie (Dwarf_CFI *cache, Dwarf_Off offset)
+{
+  const struct dwarf_cie cie_key = { .offset = offset };
+  struct dwarf_cie **found = tfind (&cie_key, &cache->cie_tree, &compare_cie);
+  if (found != NULL)
+    return *found;
+
+  /* We have not read this CIE yet.  Go find it.  */
+  Dwarf_Off next_offset = offset;
+  Dwarf_CFI_Entry entry;
+  int result = INTUSE(dwarf_next_cfi) (cache->e_ident,
+				       &cache->data->d, CFI_IS_EH (cache),
+				       offset, &next_offset, &entry);
+  if (result != 0 || entry.cie.CIE_id != DW_CIE_ID_64)
+    {
+      __libdw_seterrno (DWARF_E_INVALID_DWARF);
+      return NULL;
+    }
+
+  /* If this happened to be what we would have read next, notice it.  */
+  if (cache->next_offset == offset)
+    cache->next_offset = next_offset;
+
+  return intern_new_cie (cache, offset, &entry.cie);
+}
+
+/* Enter a CIE encountered while reading through for FDEs.  */
+void
+internal_function
+__libdw_intern_cie (Dwarf_CFI *cache, Dwarf_Off offset, const Dwarf_CIE *info)
+{
+  const struct dwarf_cie cie_key = { .offset = offset };
+  struct dwarf_cie **found = tfind (&cie_key, &cache->cie_tree, &compare_cie);
+  if (found == NULL)
+    /* We have not read this CIE yet.  Enter it.  */
+    (void) intern_new_cie (cache, offset, info);
+}