Create dwarf2/abbrev.[ch]

This moves the abbrev table code out of dwarf2read.c and into new
files dwarf2/abbrev.[ch].

gdb/ChangeLog
2020-02-08  Tom Tromey  <tom@tromey.com>

	* dwarf2read.c (abbrev_table_up, struct abbrev_info)
	(struct attr_abbrev, ABBREV_HASH_SIZE, struct abbrev_table):
	Move.
	(read_cutu_die_from_dwo, build_type_psymtabs_1): Update.
	(abbrev_table::alloc_abbrev, abbrev_table::add_abbrev)
	(abbrev_table::lookup_abbrev, abbrev_table_read_table): Move to
	abbrev.c.
	* dwarf2/abbrev.h: New file.
	* dwarf2/abbrev.c: New file, from dwarf2read.c.
	* Makefile.in (COMMON_SFILES): Add dwarf2/abbrev.c.

Change-Id: I87911bc5297de4407587ca849fef8e8d19136c30

1 files changed, 103 insertions, 0 deletions

diff --git a/gdb/dwarf2/abbrev.h b/gdb/dwarf2/abbrev.h
new file mode 100644
index 0000000..df83c09
--- /dev/null
+++ b/gdb/dwarf2/abbrev.h
@@ -0,0 +1,103 @@
+/* DWARF abbrev table
+
+   Copyright (C) 1994-2020 Free Software Foundation, Inc.
+
+   Adapted by Gary Funck (gary@intrepid.com), Intrepid Technology,
+   Inc.  with support from Florida State University (under contract
+   with the Ada Joint Program Office), and Silicon Graphics, Inc.
+   Initial contribution by Brent Benson, Harris Computer Systems, Inc.,
+   based on Fred Fish's (Cygnus Support) implementation of DWARF 1
+   support.
+
+   This file is part of GDB.
+
+   This program 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; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef GDB_DWARF2_ABBREV_H
+#define GDB_DWARF2_ABBREV_H
+
+/* This data structure holds the information of an abbrev.  */
+struct abbrev_info
+  {
+    unsigned int number;	/* number identifying abbrev */
+    enum dwarf_tag tag;		/* dwarf tag */
+    unsigned short has_children;		/* boolean */
+    unsigned short num_attrs;	/* number of attributes */
+    struct attr_abbrev *attrs;	/* an array of attribute descriptions */
+    struct abbrev_info *next;	/* next in chain */
+  };
+
+struct attr_abbrev
+  {
+    ENUM_BITFIELD(dwarf_attribute) name : 16;
+    ENUM_BITFIELD(dwarf_form) form : 16;
+
+    /* It is valid only if FORM is DW_FORM_implicit_const.  */
+    LONGEST implicit_const;
+  };
+
+/* Size of abbrev_table.abbrev_hash_table.  */
+#define ABBREV_HASH_SIZE 121
+
+/* Top level data structure to contain an abbreviation table.  */
+
+struct abbrev_table
+{
+  explicit abbrev_table (sect_offset off)
+    : sect_off (off)
+  {
+    m_abbrevs =
+      XOBNEWVEC (&abbrev_obstack, struct abbrev_info *, ABBREV_HASH_SIZE);
+    memset (m_abbrevs, 0, ABBREV_HASH_SIZE * sizeof (struct abbrev_info *));
+  }
+
+  DISABLE_COPY_AND_ASSIGN (abbrev_table);
+
+  /* Allocate space for a struct abbrev_info object in
+     ABBREV_TABLE.  */
+  struct abbrev_info *alloc_abbrev ();
+
+  /* Add an abbreviation to the table.  */
+  void add_abbrev (unsigned int abbrev_number, struct abbrev_info *abbrev);
+
+  /* Look up an abbrev in the table.
+     Returns NULL if the abbrev is not found.  */
+
+  struct abbrev_info *lookup_abbrev (unsigned int abbrev_number);
+
+
+  /* Where the abbrev table came from.
+     This is used as a sanity check when the table is used.  */
+  const sect_offset sect_off;
+
+  /* Storage for the abbrev table.  */
+  auto_obstack abbrev_obstack;
+
+private:
+
+  /* Hash table of abbrevs.
+     This is an array of size ABBREV_HASH_SIZE allocated in abbrev_obstack.
+     It could be statically allocated, but the previous code didn't so we
+     don't either.  */
+  struct abbrev_info **m_abbrevs;
+};
+
+typedef std::unique_ptr<struct abbrev_table> abbrev_table_up;
+
+extern abbrev_table_up abbrev_table_read_table
+  (struct objfile *objfile,
+   struct dwarf2_section_info *section,
+   sect_offset sect_off);
+
+#endif /* GDB_DWARF2_ABBREV_H */