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Carl Love fe6356def6 PowerPC and aarch64: Fix reverse stepping failure
When running GDB's testsuite on aarch64-linux/Ubuntu 20.04 (also spotted on
the ppc backend), there are failures in gdb.reverse/solib-precsave.exp and
gdb.reverse/solib-reverse.exp.

The failure happens around the following code:

38  b[1] = shr2(17);          /* middle part two */
40  b[0] = 6;   b[1] = 9;     /* generic statement, end part two */
42  shr1 ("message 1\n");     /* shr1 one */

Normal execution:

- step from line 38 will land on line 40.
- step from line 40 will land on line 42.

Reverse execution:
- step from line 42 will land on line 40.
- step from line 40 will land on line 40.
- step from line 40 will land on line 38.

The problem here is that line 40 contains two contiguous but distinct
PC ranges in the line table, like so:

Line 40 - [0x7ec ~ 0x7f4]
Line 40 - [0x7f4 ~ 0x7fc]

The two distinct ranges are generated because GCC started outputting source
column information, which GDB doesn't take into account at the moment.

When stepping forward from line 40, we skip both of these ranges and land on
line 42. When stepping backward from line 42, we stop at the start PC of the
second (or first, going backwards) range of line 40.

Since we've reached ecs->event_thread->control.step_range_start, we stop
stepping backwards.

The above issues were fixed by introducing a new function that looks for
adjacent PC ranges for the same line, until we notice a line change. Then
we take that as the start PC of the range.  The new start PC for the range
is used for the control.step_range_start when setting up a step range.

The test case gdb.reverse/map-to-same-line.exp is added to test the fix
for the above reverse step issues.

Patch has been tested on PowerPC, X86 and AArch64 with no regressions.
2024-01-02 17:46:02 -05:00
bfd Automatic date update in version.in 2024-01-02 00:00:57 +00:00
binutils MAINTAINERS: Update my email address 2023-12-30 00:32:00 +00:00
config libiberty: Disable hwcaps for sha1.o 2023-11-30 10:14:30 +01:00
contrib
cpu sim: frv: fix cmpb uninitialized variable usage 2024-01-01 10:56:08 -05:00
elfcpp Gold: Handle R_X86_64_CODE_4_GOTPC32_TLSDESC/R_X86_64_CODE_4_GOTTPOFF 2023-12-28 08:47:17 -08:00
etc
gas x86: Append "#pass" to APX tests 2023-12-29 15:46:59 -08:00
gdb PowerPC and aarch64: Fix reverse stepping failure 2024-01-02 17:46:02 -05:00
gdbserver gdb: change regcache interface to use array_view 2023-12-14 16:04:49 +00:00
gdbsupport Fix build with clang 16 2023-12-22 09:35:11 -07:00
gnulib gnulib: mark configure +x 2023-11-28 12:55:29 -05:00
gold Gold: Handle R_X86_64_CODE_4_GOTPC32_TLSDESC/R_X86_64_CODE_4_GOTTPOFF 2023-12-28 08:47:17 -08:00
gprof Finalized intl-update patches 2023-11-15 12:53:04 +00:00
gprofng gprofng: fix build problems on linux-musl 2023-12-22 21:10:36 -08:00
include LoongArch: include: Add support for tls le relax. 2023-12-29 15:11:00 +08:00
ld LoongArch: ld: Add support for tls le relax. 2023-12-29 15:11:01 +08:00
libbacktrace regen config 2023-08-12 10:27:57 +09:30
libctf libctf: adding CU mappings should be idempotent 2023-11-20 12:31:41 +00:00
libdecnumber regen config 2023-08-12 10:27:57 +09:30
libiberty libiberty: Fix build with GCC < 7 2023-12-05 23:34:01 +01:00
libsframe regen config 2023-08-12 10:27:57 +09:30
opcodes LoongArch: Commas inside double quotes 2023-12-30 12:59:23 +10:30
readline
sim sim: ppc: hoist pk.h creation to top-level 2024-01-02 02:22:07 -05:00
texinfo
zlib regen config 2023-08-12 10:27:57 +09:30
.cvsignore
.editorconfig
.gitattributes
.gitignore Finalized intl-update patches 2023-11-15 12:53:04 +00:00
ar-lib
ChangeLog Finalized intl-update patches 2023-11-15 12:53:04 +00:00
compile
config-ml.in MSP430: Add -fno-exceptions multilib 2023-08-12 10:24:26 +09:30
config.guess kvx: New port. 2023-08-16 14:22:54 +01:00
config.rpath
config.sub kvx: New port. 2023-08-16 14:22:54 +01:00
configure Finalized intl-update patches 2023-11-15 12:53:04 +00:00
configure.ac Finalized intl-update patches 2023-11-15 12:53:04 +00:00
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS
COPYING.NEWLIB
depcomp
djunpack.bat
install-sh
libtool.m4 FDPIC: Handle arm*-*-uclinuxfdpiceabi in configure scripts 2023-08-12 10:25:06 +09:30
lt~obsolete.m4
ltgcc.m4
ltmain.sh Do not use HAVE_DOS_BASED_FILE_SYSTEM for Cygwin. 2023-08-12 10:25:06 +09:30
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS
Makefile.def gettext: disable install, docs targets, libasprintf, threads 2023-12-18 09:39:17 -07:00
Makefile.in gettext: disable install, docs targets, libasprintf, threads 2023-12-18 09:39:17 -07:00
Makefile.tpl toplevel: Substitute GDCFLAGS instead of using CFLAGS 2023-08-12 10:27:44 +09:30
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change
multilib.am
README
README-maintainer-mode
SECURITY.txt
setup.com
src-release.sh Finalized intl-update patches 2023-11-15 12:53:04 +00:00
symlink-tree
test-driver
ylwrap

		   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

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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.