Binutils with MCST patches
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Pierre Langlois bb903df05b Add support for fast tracepoints
This patch adds support for fast tracepoints for aarch64-linux.  With this
implementation, a tracepoint can only be placed in a +/- 128MB range of
the jump pad.  This is due to the unconditional branch instruction
being limited to a (26 bit << 2) offset from the current PC.

Three target operations are implemented:

- target_install_fast_tracepoint_jump_pad

Building the jump pad the biggest change of this patch.  We need to add
functions to emit all instructions needed to save and restore the
current state when the tracepoint is hit.  As well as implementing a
lock and creating a collecting_t object identifying the current thread.

Steps performed by the jump pad:

  * Save the current state on the stack.
  * Push a collecting_t object on the stack.  We read the special
  tpidr_el0 system register to get the thread ID.
  * Spin-lock on the shared memory location of all tracing threads.  We
  write the address of our collecting_t object there once we have the
  lock.
  * Call gdb_collect.
  * Release the lock.
  * Restore the state.

  * Execute the replaced instruction which will have been relocated.
  * Jump back to the program.

- target_get_thread_area

As implemented in ps_get_thread_area, target_get_thread_area uses ptrace
to fetch the NT_ARM_TLS register.  At the architecture level, NT_ARM_TLS
represents the tpidr_el0 system register.

So this ptrace call (if lwpid is the current thread):
~~~
ptrace (PTRACE_GETREGSET, lwpid, NT_ARM_TLS, &iovec);
~~~

Is equivalent to the following instruction:
~~~
msr x0, tpidr_el0
~~~

This instruction is used when creating the collecting_t object that
GDBserver can read to know if a given thread is currently tracing.

So target_get_thread_area must get the same thread IDs as what the jump
pad writes into its collecting_t object.

- target_get_min_fast_tracepoint_insn_len

This just returns 4.

gdb/gdbserver/ChangeLog:

	* Makefile.in (linux-aarch64-ipa.o, aarch64-ipa.o): New rules.
	* configure.srv (aarch64*-*-linux*): Add linux-aarch64-ipa.o and
	aarch64-ipa.o.
	* linux-aarch64-ipa.c: New file.
	* linux-aarch64-low.c: Include arch/aarch64-insn.h, inttypes.h
	and endian.h.
	(aarch64_get_thread_area): New target method.
	(extract_signed_bitfield): New helper function.
	(aarch64_decode_ldr_literal): New function.
	(enum aarch64_opcodes): New enum.
	(struct aarch64_register): New struct.
	(struct aarch64_operand): New struct.
	(x0): New static global.
	(x1): Likewise.
	(x2): Likewise.
	(x3): Likewise.
	(x4): Likewise.
	(w2): Likewise.
	(ip0): Likewise.
	(sp): Likewise.
	(xzr): Likewise.
	(aarch64_register): New helper function.
	(register_operand): Likewise.
	(immediate_operand): Likewise.
	(struct aarch64_memory_operand): New struct.
	(offset_memory_operand): New helper function.
	(preindex_memory_operand): Likewise.
	(enum aarch64_system_control_registers): New enum.
	(ENCODE): New macro.
	(emit_insn): New helper function.
	(emit_b): New function.
	(emit_bcond): Likewise.
	(emit_cb): Likewise.
	(emit_tb): Likewise.
	(emit_blr): Likewise.
	(emit_stp): Likewise.
	(emit_ldp_q_offset): Likewise.
	(emit_stp_q_offset): Likewise.
	(emit_load_store): Likewise.
	(emit_ldr): Likewise.
	(emit_ldrsw): Likewise.
	(emit_str): Likewise.
	(emit_ldaxr): Likewise.
	(emit_stxr): Likewise.
	(emit_stlr): Likewise.
	(emit_data_processing_reg): Likewise.
	(emit_data_processing): Likewise.
	(emit_add): Likewise.
	(emit_sub): Likewise.
	(emit_mov): Likewise.
	(emit_movk): Likewise.
	(emit_mov_addr): Likewise.
	(emit_mrs): Likewise.
	(emit_msr): Likewise.
	(emit_sevl): Likewise.
	(emit_wfe): Likewise.
	(append_insns): Likewise.
	(can_encode_int32_in): New helper function.
	(aarch64_relocate_instruction): New function.
	(aarch64_install_fast_tracepoint_jump_pad): Likewise.
	(aarch64_get_min_fast_tracepoint_insn_len): Likewise.
	(struct linux_target_ops): Install aarch64_get_thread_area,
	aarch64_install_fast_tracepoint_jump_pad and
	aarch64_get_min_fast_tracepoint_insn_len.
2015-09-21 15:01:04 +01:00
bfd Automatic date update in version.in 2015-09-21 00:00:08 +00:00
binutils Adds an option to the strings program to specify a separator between the emitted pieces of text. 2015-09-10 09:29:13 +01:00
config Missing parts of fixes for in-tree libiconv 2015-08-24 10:57:03 +01:00
cpu Remove leading/trailing white spaces in ChangeLog 2015-07-24 04:16:47 -07:00
elfcpp Add chdr_size, Chdr, Chdr_write and Chdr_data 2015-04-08 10:29:40 -07:00
etc PR external/{16327,16328}: Remove etc/configure.texi and etc/standards.texi. 2014-06-27 11:33:25 +02:00
gas S/390: Fix instruction format of crj*, clrj*, and clgrj*. 2015-09-10 15:26:35 +02:00
gdb Add support for fast tracepoints 2015-09-21 15:01:04 +01:00
gold Fix internal error caused by IFUNC patch. 2015-09-07 09:44:11 -07:00
gprof Remove trailing spaces in gprof 2015-08-12 04:43:32 -07:00
include Add --no-dynamic-linker option to ld, for static PIE use 2015-09-20 15:52:27 +09:30
intl Regen intl/configure 2015-08-31 12:53:36 +09:30
ld Add --no-dynamic-linker option to ld, for static PIE use 2015-09-20 15:52:27 +09:30
libdecnumber Remove leading/trailing white spaces in ChangeLog 2015-07-24 04:16:47 -07:00
libiberty PR gdb/18669 libiberty demangle.test failure: strtod() on sparc-sun-solaris2.9 2015-08-11 09:14:12 +02:00
opcodes S/390: Fix instruction format of crj*, clrj*, and clgrj*. 2015-09-10 15:26:35 +02:00
readline Revert "Sync readline/ to version 7.0 alpha" 2015-07-25 15:57:00 -04:00
sim Fix building GDB for the M32C by providing a stub sim_info function. 2015-08-05 14:58:21 +01:00
texinfo
zlib Remove leading/trailing white spaces in ChangeLog 2015-07-24 04:16:47 -07:00
.cvsignore
.gitattributes Add a .gitattributes file for use with git-merge-changelog 2014-07-25 18:07:23 -04:00
.gitignore Sync the root .gitignore file with GCC's. 2013-01-11 15:17:35 +00:00
COPYING
COPYING.LIB
COPYING.LIBGLOSS 2013-01-07 Jeff Johnston <jjohnstn@redhat.com> 2013-01-07 21:39:26 +00:00
COPYING.NEWLIB 2013-10-01 Jeff Johnston <jjohnstn@redhat.com> 2013-10-01 18:14:04 +00:00
COPYING3
COPYING3.LIB
ChangeLog Sync config.sub and config.guess with GCC 2015-08-07 07:51:39 -07:00
MAINTAINERS Update description of ownership of files in include/ 2014-11-04 16:14:14 -08:00
Makefile.def Yaakov Selkowitz: fixes for in-tree libiconv 2015-08-06 23:55:06 -04:00
Makefile.in Yaakov Selkowitz: fixes for in-tree libiconv 2015-08-06 23:55:06 -04:00
Makefile.tpl Sync Makefile.tpl with GCC 2015-07-14 09:52:36 -07:00
README
README-maintainer-mode
compile Update from upstream Automake 2014-11-16 13:43:48 +01:00
config-ml.in Sync toplevel files with GCC 2015-07-27 07:49:05 -07:00
config.guess Sync config.sub and config.guess with GCC 2015-08-07 07:51:39 -07:00
config.rpath
config.sub Sync config.sub and config.guess with GCC 2015-08-07 07:51:39 -07:00
configure Sync toplevel files with GCC 2015-07-27 07:49:05 -07:00
configure.ac Sync toplevel files with GCC 2015-07-27 07:49:05 -07:00
depcomp Update from upstream Automake 2014-11-16 13:43:48 +01:00
djunpack.bat
install-sh Update from upstream Automake 2014-11-16 13:43:48 +01:00
libtool.m4 Update libtool.m4 from GCC trunk 2014-11-24 09:14:09 -08:00
ltgcc.m4
ltmain.sh PR target/59788 2014-02-06 11:01:57 +01:00
ltoptions.m4
ltsugar.m4
ltversion.m4
lt~obsolete.m4
makefile.vms
missing Update from upstream Automake 2014-11-16 13:43:48 +01:00
mkdep
mkinstalldirs Update from upstream Automake 2014-11-16 13:43:48 +01:00
move-if-change Update `move-if-change' from gnulib 2014-11-16 17:04:02 +01:00
setup.com
src-release.sh Adjust src-release.sh for sim using the gdb create-version.sh. 2015-04-15 04:08:51 +02:00
symlink-tree
ylwrap Update from upstream Automake 2014-11-16 13:43:48 +01:00

README

		   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.