gdb10: Fixes for ARC

Here we add a couple of fixes and improvements for ARC processors.
All except 1 patch are already in the upstream "master" branch
and will be an essential part of GCC 11.x whenever it gets released.

The most important are first 4 patches (0005-0008) which introduce
support of full native GDB support in Linux on ARC.

And the rests are tiny, yet useful improvements.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

1 files changed, 110 insertions, 0 deletions

diff --git a/packages/gdb/10.2/0007-arc-Take-into-account-the-REGNUM-in-supply-collect-g.patch b/packages/gdb/10.2/0007-arc-Take-into-account-the-REGNUM-in-supply-collect-g.patch
new file mode 100644
index 0000000..98a889f
--- /dev/null
+++ b/packages/gdb/10.2/0007-arc-Take-into-account-the-REGNUM-in-supply-collect-g.patch
@@ -0,0 +1,110 @@
+From 7cf6f67aee277a37a7c648ca41a46a2c04aec2ed Mon Sep 17 00:00:00 2001
+From: Shahab Vahedi <shahab@synopsys.com>
+Date: Tue, 10 Nov 2020 19:34:57 +0100
+Subject: [PATCH 08/20] arc: Take into account the REGNUM in supply/collect gdb
+ hooks
+
+All the arc_linux_supply_*() target operations and the
+arc_linux_collect_v2_regset() in arc-linux-tdep.c were
+supplying/collecting all the registers in regcache as if the
+REGNUM was set to -1.
+
+The more efficient behavior is to examine the REGNUM and act
+accordingly.  That is what this patch does.
+
+gdb/ChangeLog:
+
+	* arc-linux-tdep.c (supply_register): New.
+	(arc_linux_supply_gregset, arc_linux_supply_v2_regset,
+	arc_linux_collect_v2_regset): Consider REGNUM.
+
+Will be a part of GDB 11:
+https://sourceware.org/git?p=binutils-gdb.git;a=commit;h=46023bbe81355230b4e7b76d3084337823d02362
+---
+ gdb/ChangeLog        |    6 ++++++
+ gdb/arc-linux-tdep.c |   41 ++++++++++++++++++++++++++++++++---------
+ 2 files changed, 38 insertions(+), 9 deletions(-)
+
+--- a/gdb/ChangeLog
++++ b/gdb/ChangeLog
+@@ -1,3 +1,9 @@
++2020-12-22  Shahab Vahedi  <shahab@synopsys.com>
++
++	* arc-linux-tdep.c (supply_register): New.
++	(arc_linux_supply_gregset, arc_linux_supply_v2_regset,
++	arc_linux_collect_v2_regset): Consider REGNUM.
++
+ 2020-12-22  Anton Kolesov  <anton.kolesov@synopsys.com>
+ 
+ 	* arc-linux-tdep.c (arc_linux_sc_reg_offsets): New static variable.
+--- a/gdb/arc-linux-tdep.c
++++ b/gdb/arc-linux-tdep.c
+@@ -535,6 +535,18 @@
+     }
+ }
+ 
++/* Populate REGCACHE with register REGNUM from BUF.  */
++
++static void
++supply_register (struct regcache *regcache, int regnum, const gdb_byte *buf)
++{
++  /* Skip non-existing registers.  */
++  if ((arc_linux_core_reg_offsets[regnum] == ARC_OFFSET_NO_REGISTER))
++    return;
++
++  regcache->raw_supply (regnum, buf + arc_linux_core_reg_offsets[regnum]);
++}
++
+ void
+ arc_linux_supply_gregset (const struct regset *regset,
+ 			  struct regcache *regcache,
+@@ -545,9 +557,14 @@
+ 
+   const bfd_byte *buf = (const bfd_byte *) gregs;
+ 
+-  for (int reg = 0; reg <= ARC_LAST_REGNUM; reg++)
+-      if (arc_linux_core_reg_offsets[reg] != ARC_OFFSET_NO_REGISTER)
+-	regcache->raw_supply (reg, buf + arc_linux_core_reg_offsets[reg]);
++  /* regnum == -1 means writing all the registers.  */
++  if (regnum == -1)
++    for (int reg = 0; reg <= ARC_LAST_REGNUM; reg++)
++      supply_register (regcache, reg, buf);
++  else if (regnum <= ARC_LAST_REGNUM)
++    supply_register (regcache, regnum, buf);
++  else
++    gdb_assert_not_reached ("Invalid regnum in arc_linux_supply_gregset.");
+ }
+ 
+ void
+@@ -558,9 +575,12 @@
+   const bfd_byte *buf = (const bfd_byte *) v2_regs;
+ 
+   /* user_regs_arcv2 is defined in linux arch/arc/include/uapi/asm/ptrace.h.  */
+-  regcache->raw_supply (ARC_R30_REGNUM, buf);
+-  regcache->raw_supply (ARC_R58_REGNUM, buf + REGOFF (1));
+-  regcache->raw_supply (ARC_R59_REGNUM, buf + REGOFF (2));
++  if (regnum == -1 || regnum == ARC_R30_REGNUM)
++    regcache->raw_supply (ARC_R30_REGNUM, buf);
++  if (regnum == -1 || regnum == ARC_R58_REGNUM)
++    regcache->raw_supply (ARC_R58_REGNUM, buf + REGOFF (1));
++  if (regnum == -1 || regnum == ARC_R59_REGNUM)
++    regcache->raw_supply (ARC_R59_REGNUM, buf + REGOFF (2));
+ }
+ 
+ /* Populate BUF with register REGNUM from the REGCACHE.  */
+@@ -618,9 +638,12 @@
+ {
+   bfd_byte *buf = (bfd_byte *) v2_regs;
+ 
+-  regcache->raw_collect (ARC_R30_REGNUM, buf);
+-  regcache->raw_collect (ARC_R58_REGNUM, buf + REGOFF (1));
+-  regcache->raw_collect (ARC_R59_REGNUM, buf + REGOFF (2));
++  if (regnum == -1 || regnum == ARC_R30_REGNUM)
++    regcache->raw_collect (ARC_R30_REGNUM, buf);
++  if (regnum == -1 || regnum == ARC_R58_REGNUM)
++    regcache->raw_collect (ARC_R58_REGNUM, buf + REGOFF (1));
++  if (regnum == -1 || regnum == ARC_R59_REGNUM)
++    regcache->raw_collect (ARC_R59_REGNUM, buf + REGOFF (2));
+ }
+ 
+ /* Linux regset definitions.  */