From 7cf6f67aee277a37a7c648ca41a46a2c04aec2ed Mon Sep 17 00:00:00 2001 From: Shahab Vahedi 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 + + * 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 * 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. */