Markus Metzger b61ce85cc5 btrace: allow leading trace gaps
GDB ignores trace gaps from decode errors or overflows at the beginning of the
trace.  There isn't really a gap in the trace; the trace just starts a bit
later than expected.

In cases where there is no trace at all or where the trace is smaller than
expected, this may hide the reason for the missing trace.

Allow leading trace gaps.  They will be shown as decode warnings and by the
record function-call-history command.

    (gdb) info record
    Active record target: record-btrace
    Recording format: Intel Processor Trace.
    Buffer size: 16kB.
    warning: Decode error (-6) at instruction 0 (offset = 0x58, pc = 0x0): unexpected packet context.
    warning: Decode error (-6) at instruction 0 (offset = 0xb0, pc = 0x0): unexpected packet context.
    warning: Decode error (-6) at instruction 0 (offset = 0x168, pc = 0x0): unexpected packet context.
    warning: Decode error (-6) at instruction 54205 (offset = 0xe08, pc = 0x0): unexpected packet context.
    warning: Decode error (-6) at instruction 54205 (offset = 0xe60, pc = 0x0): unexpected packet context.
    warning: Decode error (-6) at instruction 54205 (offset = 0xed8, pc = 0x0): unexpected packet context.
    Recorded 91582 instructions in 1111 functions (6 gaps) for thread 1 (process 15710).
    (gdb) record function-call-history /c 1
    1       [decode error (-6): unexpected packet context]
    2       [decode error (-6): unexpected packet context]
    3       [decode error (-6): unexpected packet context]
    4           _dl_addr
    5             ??
    6           _dl_addr
    7         ??
    8           ??
    9         ??
    10      ??

Leading trace gaps will not be shown by the record instruction-history command
without further changes.

gdb/
	* btrace.c (btrace_compute_ftrace_bts, ftrace_add_pt): Allow leading gaps.
	* record-btrace.c (record_btrace_single_step_forward)
	(record_btrace_single_step_backward): Jump back to last instruction if
	step ends at a gap.
	(record_btrace_goto_begin): Skip gaps.
2016-10-28 10:53:45 +02:00
2016-10-28 00:00:18 +00:00
2016-10-28 10:53:45 +02:00
2016-10-21 11:10:46 -07:00
2016-10-15 12:53:57 +10:30
2016-10-21 12:16:32 -07:00

		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
If with a binutils release, see binutils/README;  if with a libg++ release,
see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

It is now possible to automatically configure and build a variety of
tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

To install them (by default in /usr/local/bin, /usr/local/lib, etc),
then do:
	make install

(If the configure script can't determine your type of computer, give it
the name as an argument, for instance ``./configure sun4''.  You can
use the script ``config.sub'' to test whether a name is recognized; if
it is, config.sub translates it to a triplet specifying CPU, vendor,
and OS.)

If you have more than one compiler on your system, it is often best to
explicitly set CC in the environment before running configure, and to
also set CC when running make.  For example (assuming sh/bash/ksh):

	CC=gcc ./configure
	make

A similar example using csh:

	setenv CC gcc
	./configure
	make

Much of the code and documentation enclosed is copyright by
the Free Software Foundation, Inc.  See the file COPYING or
COPYING.LIB in the various directories, for a description of the
GNU General Public License terms under which you can copy the files.

REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info
on where and how to report problems.
Description
GDB that can debug Mach-Os on Linux
Readme 280 MiB
Languages
C 58.3%
Makefile 18.5%
Assembly 13.3%
C++ 3.6%
Scheme 1.2%
Other 4.7%