[PATCH v2 0/2] Add native GNU/Linux support for ARC in GDB

[Shahab Vahedi via Gdb-patches <gdb-patches@sourceware.org>]

From: Shahab Vahedi <shahab@synopsys.com>

This patch series is mainly about adding a native GNU/Linux support for
ARC in GDB ("[PATCH 2/2] gdb: Add native support for ARC in GNU/Linux").

During the process of mulling over that change, I noticed that the ARC
target support could become more efficient in some of the target hooks
in "arc-linux-tdep.c"; namely the "arc_linux_supply_*()" and the
"arc_linux_collect_v2_regset()".  In those hooks, REGNUM is completely
ignored and every register is fetched/overwritten.  These hooks are
used by the "arc-linux-nat.c" (the second patch) and it relies on them:
Therefore, the first patch of this series: "[PATCH 1/2]: arc: Take into
account the REGNUM in supply/collect gdb hooks".

To summarize:
[PATCH 1/2] -> Respect REGNUM in hooks.
[PATCH 2/2] -> Add native ARC GNU/Linux support while using those hooks.

One last remark: The native GDB works correctly along with this
fix [1].  Therefore, if you want to give it a try, please also apply
that patch.

[1] [PATCH] arc: Write correct "eret" value during register collection
https://sourceware.org/pipermail/gdb-patches/2020-November/173202.html

How to build:
Get the "Linux/{glibc,uClibc} ARC HS" toolchain from:
https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases
and extract it somewhere.

Update the PATHs so you can find "arc-linux-gcc":
$ export PATH=/extracted/dir/bin:$PATH
$ export LD_LIBRARY_PATH=/extracted/dir/lib:$LD_LIBRARY_PATH

$ cd /to/gdb/src
$ host=arc-snps-linux-gnu            # or arc-snps-linux-uclibc
$ configure --prefix=/usr            \
            --host=$host             \
            --disable-build-with-cxx \
            --disable-gas            \
            --disable-ld             \
            --disable-binutils
$ make -j $(nproc)
$ arc-linux-strip ./gdb/gdb

v2:
Because there was only some remarks about the second patch in this
series, that is the one that has been reworked. Look at its commit
message to see what has exactly changed.

Anton Kolesov (1):
  gdb: Add native support for ARC in GNU/Linux

Shahab Vahedi (1):
  arc: Take into account the REGNUM in supply/collect gdb hooks

 gdb/Makefile.in      |   1 +
 gdb/arc-linux-nat.c  | 320 +++++++++++++++++++++++++++++++++++++++++++
 gdb/arc-linux-tdep.c |  41 ++++--
 gdb/configure.host   |   3 +
 gdb/configure.nat    |   4 +
 5 files changed, 360 insertions(+), 9 deletions(-)
 create mode 100644 gdb/arc-linux-nat.c

-- 
2.29.2