Create dwarf2/leb.[ch]

This moves some scalar-unpacking code into a couple of new files,
dwarf2/leb.h and dwarf2/leb.c.

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

	* dwarf2read.h (read_unsigned_leb128): Don't declare.
	* dwarf2read.c (read_1_byte, read_1_signed_byte, read_2_bytes)
	(read_2_signed_bytes, read_3_bytes, read_4_bytes)
	(read_4_signed_bytes, read_8_bytes): Move to dwarf2/leb.h.
	(read_unsigned_leb128, read_signed_leb128): Move to dwarf2/leb.c.
	* dwarf2/leb.h: New file, from dwarf2read.c.
	* dwarf2/leb.c: New file, from dwarf2read.c.
	* dwarf2-frame.c (read_1_byte, read_4_bytes, read_8_bytes):
	Remove.
	* Makefile.in (CONFIG_SRC_SUBDIR): Add dwarf2.
	(COMMON_SFILES): Add dwarf2/leb.c.

Change-Id: Idd19647686c8f959d226a95fdfca4db47c6e96d0

8 files changed, 196 insertions, 149 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 07353b7..d0c5d4a 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,17 @@
+2020-02-08  Tom Tromey  <tom@tromey.com>
+
+	* dwarf2read.h (read_unsigned_leb128): Don't declare.
+	* dwarf2read.c (read_1_byte, read_1_signed_byte, read_2_bytes)
+	(read_2_signed_bytes, read_3_bytes, read_4_bytes)
+	(read_4_signed_bytes, read_8_bytes): Move to dwarf2/leb.h.
+	(read_unsigned_leb128, read_signed_leb128): Move to dwarf2/leb.c.
+	* dwarf2/leb.h: New file, from dwarf2read.c.
+	* dwarf2/leb.c: New file, from dwarf2read.c.
+	* dwarf2-frame.c (read_1_byte, read_4_bytes, read_8_bytes):
+	Remove.
+	* Makefile.in (CONFIG_SRC_SUBDIR): Add dwarf2.
+	(COMMON_SFILES): Add dwarf2/leb.c.
+
 2020-02-08  Joel Brobecker  <brobecker@adacore.com>
 
 	GDB 9.1 released.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 49fff37..b30ab54 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -551,7 +551,7 @@ CONFIG_INSTALL = @CONFIG_INSTALL@
 CONFIG_UNINSTALL = @CONFIG_UNINSTALL@
 HAVE_NATIVE_GCORE_TARGET = @HAVE_NATIVE_GCORE_TARGET@
 
-CONFIG_SRC_SUBDIR = arch cli mi compile tui unittests guile python \
+CONFIG_SRC_SUBDIR = arch cli dwarf2 mi compile tui unittests guile python \
 	target nat
 CONFIG_DEP_SUBDIR = $(addsuffix /$(DEPDIR),$(CONFIG_SRC_SUBDIR))
 
@@ -1002,6 +1002,7 @@ COMMON_SFILES = \
 	dwarf2expr.c \
 	dwarf2loc.c \
 	dwarf2read.c \
+	dwarf2/leb.c \
 	eval.c \
 	event-loop.c \
 	event-top.c \
diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c
index 40eb7f5..2bf8271 100644
--- a/gdb/dwarf2-frame.c
+++ b/gdb/dwarf2-frame.c
@@ -22,6 +22,7 @@
 #include "defs.h"
 #include "dwarf2expr.h"
 #include "dwarf2.h"
+#include "dwarf2/leb.h"
 #include "frame.h"
 #include "frame-base.h"
 #include "frame-unwind.h"
@@ -1474,23 +1475,6 @@ const struct objfile_key<dwarf2_fde_table,
 			 gdb::noop_deleter<dwarf2_fde_table>>
   dwarf2_frame_objfile_data;
 
-static unsigned int
-read_1_byte (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_8 (abfd, buf);
-}
-
-static unsigned int
-read_4_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_32 (abfd, buf);
-}
-
-static ULONGEST
-read_8_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_64 (abfd, buf);
-}
 
 static ULONGEST
 read_initial_length (bfd *abfd, const gdb_byte *buf,
diff --git a/gdb/dwarf2/leb.c b/gdb/dwarf2/leb.c
new file mode 100644
index 0000000..d26b48b
--- /dev/null
+++ b/gdb/dwarf2/leb.c
@@ -0,0 +1,85 @@
+/* Low-level DWARF 2 reading code
+
+   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/>.  */
+
+#include "defs.h"
+#include "dwarf2/leb.h"
+
+ULONGEST
+read_unsigned_leb128 (bfd *abfd, const gdb_byte *buf,
+			  unsigned int *bytes_read_ptr)
+{
+  ULONGEST result;
+  unsigned int num_read;
+  int shift;
+  unsigned char byte;
+
+  result = 0;
+  shift = 0;
+  num_read = 0;
+  while (1)
+    {
+      byte = bfd_get_8 (abfd, buf);
+      buf++;
+      num_read++;
+      result |= ((ULONGEST) (byte & 127) << shift);
+      if ((byte & 128) == 0)
+	{
+	  break;
+	}
+      shift += 7;
+    }
+  *bytes_read_ptr = num_read;
+  return result;
+}
+
+LONGEST
+read_signed_leb128 (bfd *abfd, const gdb_byte *buf,
+		    unsigned int *bytes_read_ptr)
+{
+  ULONGEST result;
+  int shift, num_read;
+  unsigned char byte;
+
+  result = 0;
+  shift = 0;
+  num_read = 0;
+  while (1)
+    {
+      byte = bfd_get_8 (abfd, buf);
+      buf++;
+      num_read++;
+      result |= ((ULONGEST) (byte & 127) << shift);
+      shift += 7;
+      if ((byte & 128) == 0)
+	{
+	  break;
+	}
+    }
+  if ((shift < 8 * sizeof (result)) && (byte & 0x40))
+    result |= -(((ULONGEST) 1) << shift);
+  *bytes_read_ptr = num_read;
+  return result;
+}
diff --git a/gdb/dwarf2/leb.h b/gdb/dwarf2/leb.h
new file mode 100644
index 0000000..b17ab88
--- /dev/null
+++ b/gdb/dwarf2/leb.h
@@ -0,0 +1,92 @@
+/* Low-level DWARF 2 reading code
+
+   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_LEB_H
+#define GDB_DWARF2_LEB_H
+
+/* Read dwarf information from a buffer.  */
+
+static inline unsigned int
+read_1_byte (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_8 (abfd, buf);
+}
+
+static inline int
+read_1_signed_byte (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_signed_8 (abfd, buf);
+}
+
+static inline unsigned int
+read_2_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_16 (abfd, buf);
+}
+
+static inline int
+read_2_signed_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_signed_16 (abfd, buf);
+}
+
+/* Read the next three bytes (little-endian order) as an unsigned integer.  */
+static inline unsigned int
+read_3_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  unsigned int result = 0;
+  for (int i = 0; i < 3; ++i)
+    {
+      unsigned char byte = bfd_get_8 (abfd, buf);
+      buf++;
+      result |= ((unsigned int) byte << (i * 8));
+    }
+  return result;
+}
+
+static inline unsigned int
+read_4_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_32 (abfd, buf);
+}
+
+static inline int
+read_4_signed_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_signed_32 (abfd, buf);
+}
+
+static inline ULONGEST
+read_8_bytes (bfd *abfd, const gdb_byte *buf)
+{
+  return bfd_get_64 (abfd, buf);
+}
+
+extern LONGEST read_signed_leb128 (bfd *, const gdb_byte *, unsigned int *);
+
+extern ULONGEST read_unsigned_leb128 (bfd *, const gdb_byte *, unsigned int *);
+
+#endif /* GDB_DWARF2_LEB_H */
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 405b239..9cfc852 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -38,6 +38,7 @@
 #include "dwarf2loc.h"
 #include "dwarf2read.h"
 #include "dwarf2-frame.h"
+#include "dwarf2/leb.h"
 #include "compile/compile.h"
 #include "gdbsupport/selftest.h"
 #include <algorithm>
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index dafe01d..fe26fc3 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -32,6 +32,7 @@
 #include "dwarf2read.h"
 #include "dwarf-index-cache.h"
 #include "dwarf-index-common.h"
+#include "dwarf2/leb.h"
 #include "bfd.h"
 #include "elf-bfd.h"
 #include "symtab.h"
@@ -1551,19 +1552,6 @@ static void read_attribute_reprocess (const struct die_reader_specs *reader,
 
 static CORE_ADDR read_addr_index (struct dwarf2_cu *cu, unsigned int addr_index);
 
-static unsigned int read_1_byte (bfd *, const gdb_byte *);
-
-static int read_1_signed_byte (bfd *, const gdb_byte *);
-
-static unsigned int read_2_bytes (bfd *, const gdb_byte *);
-
-/* Read the next three bytes (little-endian order) as an unsigned integer.  */
-static unsigned int read_3_bytes (bfd *, const gdb_byte *);
-
-static unsigned int read_4_bytes (bfd *, const gdb_byte *);
-
-static ULONGEST read_8_bytes (bfd *, const gdb_byte *);
-
 static CORE_ADDR read_address (bfd *, const gdb_byte *ptr, struct dwarf2_cu *,
 			       unsigned int *);
 
@@ -1602,8 +1590,6 @@ static const char *read_indirect_string_at_offset
 static const char *read_indirect_string_from_dwz
   (struct objfile *objfile, struct dwz_file *, LONGEST);
 
-static LONGEST read_signed_leb128 (bfd *, const gdb_byte *, unsigned int *);
-
 static CORE_ADDR read_addr_index_from_leb128 (struct dwarf2_cu *,
 					      const gdb_byte *,
 					      unsigned int *);
@@ -19685,63 +19671,6 @@ read_attribute (const struct die_reader_specs *reader,
 			       need_reprocess);
 }
 
-/* Read dwarf information from a buffer.  */
-
-static unsigned int
-read_1_byte (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_8 (abfd, buf);
-}
-
-static int
-read_1_signed_byte (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_signed_8 (abfd, buf);
-}
-
-static unsigned int
-read_2_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_16 (abfd, buf);
-}
-
-static int
-read_2_signed_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_signed_16 (abfd, buf);
-}
-
-static unsigned int
-read_3_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  unsigned int result = 0;
-  for (int i = 0; i < 3; ++i)
-    {
-      unsigned char byte = bfd_get_8 (abfd, buf);
-      buf++;
-      result |= ((unsigned int) byte << (i * 8));
-    }
-  return result;
-}
-
-static unsigned int
-read_4_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_32 (abfd, buf);
-}
-
-static int
-read_4_signed_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_signed_32 (abfd, buf);
-}
-
-static ULONGEST
-read_8_bytes (bfd *abfd, const gdb_byte *buf)
-{
-  return bfd_get_64 (abfd, buf);
-}
-
 static CORE_ADDR
 read_address (bfd *abfd, const gdb_byte *buf, struct dwarf2_cu *cu,
 	      unsigned int *bytes_read)
@@ -20051,63 +19980,6 @@ read_indirect_line_string (struct dwarf2_per_objfile *dwarf2_per_objfile,
 					      str_offset);
 }
 
-ULONGEST
-read_unsigned_leb128 (bfd *abfd, const gdb_byte *buf,
-			  unsigned int *bytes_read_ptr)
-{
-  ULONGEST result;
-  unsigned int num_read;
-  int shift;
-  unsigned char byte;
-
-  result = 0;
-  shift = 0;
-  num_read = 0;
-  while (1)
-    {
-      byte = bfd_get_8 (abfd, buf);
-      buf++;
-      num_read++;
-      result |= ((ULONGEST) (byte & 127) << shift);
-      if ((byte & 128) == 0)
-	{
-	  break;
-	}
-      shift += 7;
-    }
-  *bytes_read_ptr = num_read;
-  return result;
-}
-
-static LONGEST
-read_signed_leb128 (bfd *abfd, const gdb_byte *buf,
-		    unsigned int *bytes_read_ptr)
-{
-  ULONGEST result;
-  int shift, num_read;
-  unsigned char byte;
-
-  result = 0;
-  shift = 0;
-  num_read = 0;
-  while (1)
-    {
-      byte = bfd_get_8 (abfd, buf);
-      buf++;
-      num_read++;
-      result |= ((ULONGEST) (byte & 127) << shift);
-      shift += 7;
-      if ((byte & 128) == 0)
-	{
-	  break;
-	}
-    }
-  if ((shift < 8 * sizeof (result)) && (byte & 0x40))
-    result |= -(((ULONGEST) 1) << shift);
-  *bytes_read_ptr = num_read;
-  return result;
-}
-
 /* Given index ADDR_INDEX in .debug_addr, fetch the value.
    ADDR_BASE is the DW_AT_addr_base (DW_AT_GNU_addr_base) attribute or zero.
    ADDR_SIZE is the size of addresses from the CU header.  */
diff --git a/gdb/dwarf2read.h b/gdb/dwarf2read.h
index 3f9731f..5aa9421 100644
--- a/gdb/dwarf2read.h
+++ b/gdb/dwarf2read.h
@@ -463,8 +463,6 @@ struct signatured_type
   struct dwo_unit *dwo_unit;
 };
 
-ULONGEST read_unsigned_leb128 (bfd *, const gdb_byte *, unsigned int *);
-
 /* This represents a '.dwz' file.  */
 
 struct dwz_file