From cc463201c4bbe5d0708ef4b45b17fb7c3fed6aee Mon Sep 17 00:00:00 2001 From: Anton Kolesov Date: Mon, 30 Jan 2017 18:32:10 +0300 Subject: [PATCH] arc: Add support for Linux coredump files With the implemenations in this patch, ARC gdb can handle coredump related matters. The binutils counter part of this patch has already been pushed [1]. v2 [2]: - arc_linux_collect_gregset: Use "reg <= ARC_LAST_REGNUM" instead of "reg < ARC_LAST_REGNUM" for the condition check of the for-loop. - arc-linux-tdep.c: Use "ARC_LAST_REGNUM < ARRAY_SIZE (...)" instead of "ARC_LAST_REGNUM <= ARRAY_SIZE (...)" for the "asserts". - Use "buf + arc_linux_core_reg_offsets[ARC_ERET_REGNUM]" instead of "buf + REG_OFF (6)". - Fix a few typos/indentation. v3 [3]: - Use gdb_assert_not_reached(text) instead of gdb_assert (!text). - Remove unnecessary braces in the for loop. [1] arc: Add support for ARC HS extra registers in core files https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=2745674244d6aecddcf636475034bdb9c0a6b4a0 [2] First remarks https://sourceware.org/pipermail/gdb-patches/2020-September/171912.html [3] Second remarks https://sourceware.org/pipermail/gdb-patches/2020-October/172302.html gdb/ChangeLog: * arc-linux-tdep.h: New file. * arc-linux-tdep.c (arc_linux_core_reg_offsets, arc_linux_supply_gregset, arc_linux_supply_v2_regset, arc_linux_collect_gregset, arc_linux_collect_v2_regset, arc_linux_gregset, arc_linux_v2_regset, arc_linux_iterate_over_regset_sections, arc_linux_core_read_description): Implement. (arc_linux_init_osabi): Set iterate_over_regset_sections. * arc-tdep.h (ARC_OFFSET_NO_REGISTER): Declare. (arc_gdbarch_features_create): Add. * arc-tdep.c (arc_gdbarch_features_create): Not static anymore. --- gdb/ChangeLog | 14 ++++ gdb/arc-linux-tdep.c | 191 +++++++++++++++++++++++++++++++++++++++++++ gdb/arc-linux-tdep.h | 52 ++++++++++++ gdb/arc-tdep.c | 5 +- gdb/arc-tdep.h | 12 ++- 5 files changed, 270 insertions(+), 4 deletions(-) create mode 100644 gdb/arc-linux-tdep.h diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 3caea814a67..3e72d920ae4 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,17 @@ +2020-10-07 Anton Kolesov + + * arc-linux-tdep.h: New file. + * arc-linux-tdep.c (arc_linux_core_reg_offsets, + arc_linux_supply_gregset, arc_linux_supply_v2_regset, + arc_linux_collect_gregset, arc_linux_collect_v2_regset, + arc_linux_gregset, arc_linux_v2_regset, + arc_linux_iterate_over_regset_sections, + arc_linux_core_read_description): Implement. + (arc_linux_init_osabi): Set iterate_over_regset_sections. + * arc-tdep.h (ARC_OFFSET_NO_REGISTER): Declare. + (arc_gdbarch_features_create): Add. + * arc-tdep.c (arc_gdbarch_features_create): Not static anymore. + 2020-10-07 Shahab Vahedi * arch/arc.h: Rename "arc_gdbarch_features" to diff --git a/gdb/arc-linux-tdep.c b/gdb/arc-linux-tdep.c index 36f32459bbe..9ff5f1214a1 100644 --- a/gdb/arc-linux-tdep.c +++ b/gdb/arc-linux-tdep.c @@ -27,7 +27,65 @@ /* ARC header files. */ #include "opcodes/arc-dis.h" +#include "arc-linux-tdep.h" #include "arc-tdep.h" +#include "arch/arc.h" + +#define REGOFF(offset) (offset * ARC_REGISTER_SIZE) + +/* arc_linux_core_reg_offsets[i] is the offset in the .reg section of GDB + regnum i. Array index is an internal GDB register number, as defined in + arc-tdep.h:arc_regnum. + + From include/uapi/asm/ptrace.h in the ARC Linux sources. */ + +/* The layout of this struct is tightly bound to "arc_regnum" enum + in arc-tdep.h. Any change of order in there, must be reflected + here as well. */ +static const int arc_linux_core_reg_offsets[] = { + /* R0 - R12. */ + REGOFF (22), REGOFF (21), REGOFF (20), REGOFF (19), + REGOFF (18), REGOFF (17), REGOFF (16), REGOFF (15), + REGOFF (14), REGOFF (13), REGOFF (12), REGOFF (11), + REGOFF (10), + + /* R13 - R25. */ + REGOFF (37), REGOFF (36), REGOFF (35), REGOFF (34), + REGOFF (33), REGOFF (32), REGOFF (31), REGOFF (30), + REGOFF (29), REGOFF (28), REGOFF (27), REGOFF (26), + REGOFF (25), + + REGOFF (9), /* R26 (GP) */ + REGOFF (8), /* FP */ + REGOFF (23), /* SP */ + ARC_OFFSET_NO_REGISTER, /* ILINK */ + ARC_OFFSET_NO_REGISTER, /* R30 */ + REGOFF (7), /* BLINK */ + + /* R32 - R59. */ + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, ARC_OFFSET_NO_REGISTER, + ARC_OFFSET_NO_REGISTER, + + REGOFF (4), /* LP_COUNT */ + ARC_OFFSET_NO_REGISTER, /* RESERVED */ + ARC_OFFSET_NO_REGISTER, /* LIMM */ + ARC_OFFSET_NO_REGISTER, /* PCL */ + + REGOFF (39), /* PC */ + REGOFF (5), /* STATUS32 */ + REGOFF (2), /* LP_START */ + REGOFF (3), /* LP_END */ + REGOFF (1), /* BTA */ + REGOFF (6) /* ERET */ +}; /* Implement the "cannot_fetch_register" gdbarch method. */ @@ -227,6 +285,136 @@ arc_linux_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc) } } +void +arc_linux_supply_gregset (const struct regset *regset, + struct regcache *regcache, + int regnum, const void *gregs, size_t size) +{ + gdb_static_assert (ARC_LAST_REGNUM + < ARRAY_SIZE (arc_linux_core_reg_offsets)); + + 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]); +} + +void +arc_linux_supply_v2_regset (const struct regset *regset, + struct regcache *regcache, int regnum, + const void *v2_regs, size_t size) +{ + 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)); +} + +/* Populate BUF with register REGNUM from the REGCACHE. */ + +static void +collect_register (const struct regcache *regcache, struct gdbarch *gdbarch, + int regnum, gdb_byte *buf) +{ + /* Skip non-existing registers. */ + if ((arc_linux_core_reg_offsets[regnum] == ARC_OFFSET_NO_REGISTER)) + return; + + /* The address where the execution has stopped is in pseudo-register + STOP_PC. However, when kernel code is returning from the exception, + it uses the value from ERET register. Since, TRAP_S (the breakpoint + instruction) commits, the ERET points to the next instruction. In + other words: ERET != STOP_PC. To jump back from the kernel code to + the correct address, ERET must be overwritten by GDB's STOP_PC. Else, + the program will continue at the address after the current instruction. + */ + if (regnum == gdbarch_pc_regnum (gdbarch)) + regnum = ARC_ERET_REGNUM; + regcache->raw_collect (regnum, buf + arc_linux_core_reg_offsets[regnum]); +} + +void +arc_linux_collect_gregset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *gregs, size_t size) +{ + gdb_static_assert (ARC_LAST_REGNUM + < ARRAY_SIZE (arc_linux_core_reg_offsets)); + + gdb_byte *buf = (gdb_byte *) gregs; + struct gdbarch *gdbarch = regcache->arch (); + + /* regnum == -1 means writing all the registers. */ + if (regnum == -1) + for (int reg = 0; reg <= ARC_LAST_REGNUM; reg++) + collect_register (regcache, gdbarch, reg, buf); + else if (regnum <= ARC_LAST_REGNUM) + collect_register (regcache, gdbarch, regnum, buf); + else + gdb_assert_not_reached ("Invalid regnum in arc_linux_collect_gregset."); +} + +void +arc_linux_collect_v2_regset (const struct regset *regset, + const struct regcache *regcache, int regnum, + void *v2_regs, size_t size) +{ + 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)); +} + +/* Linux regset definitions. */ + +static const struct regset arc_linux_gregset = { + arc_linux_core_reg_offsets, + arc_linux_supply_gregset, + arc_linux_collect_gregset, +}; + +static const struct regset arc_linux_v2_regset = { + NULL, + arc_linux_supply_v2_regset, + arc_linux_collect_v2_regset, +}; + +/* Implement the `iterate_over_regset_sections` gdbarch method. */ + +static void +arc_linux_iterate_over_regset_sections (struct gdbarch *gdbarch, + iterate_over_regset_sections_cb *cb, + void *cb_data, + const struct regcache *regcache) +{ + /* There are 40 registers in Linux user_regs_struct, although some of + them are now just a mere paddings, kept to maintain binary + compatibility with older tools. */ + const int sizeof_gregset = 40 * ARC_REGISTER_SIZE; + + cb (".reg", sizeof_gregset, sizeof_gregset, &arc_linux_gregset, NULL, + cb_data); + cb (".reg-arc-v2", ARC_LINUX_SIZEOF_V2_REGSET, ARC_LINUX_SIZEOF_V2_REGSET, + &arc_linux_v2_regset, NULL, cb_data); +} + +/* Implement the `core_read_description` gdbarch method. */ + +static const struct target_desc * +arc_linux_core_read_description (struct gdbarch *gdbarch, + struct target_ops *target, + bfd *abfd) +{ + arc_arch_features features + = arc_arch_features_create (abfd, + gdbarch_bfd_arch_info (gdbarch)->mach); + return arc_lookup_target_description (features); +} + /* Initialization specific to Linux environment. */ static void @@ -260,6 +448,9 @@ arc_linux_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_software_single_step (gdbarch, arc_linux_software_single_step); set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); set_gdbarch_skip_solib_resolver (gdbarch, arc_linux_skip_solib_resolver); + set_gdbarch_iterate_over_regset_sections + (gdbarch, arc_linux_iterate_over_regset_sections); + set_gdbarch_core_read_description (gdbarch, arc_linux_core_read_description); /* GNU/Linux uses SVR4-style shared libraries, with 32-bit ints, longs and pointers (ILP32). */ diff --git a/gdb/arc-linux-tdep.h b/gdb/arc-linux-tdep.h new file mode 100644 index 00000000000..c26cacd7029 --- /dev/null +++ b/gdb/arc-linux-tdep.h @@ -0,0 +1,52 @@ +/* Target dependent code for GNU/Linux ARC. + + Copyright 2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#ifndef ARC_LINUX_TDEP_H +#define ARC_LINUX_TDEP_H + +#include "gdbarch.h" +#include "regset.h" + +#define ARC_LINUX_SIZEOF_V2_REGSET (3 * ARC_REGISTER_SIZE) + +/* Reads registers from the NT_PRSTATUS data array into the regcache. */ + +void arc_linux_supply_gregset (const struct regset *regset, + struct regcache *regcache, int regnum, + const void *gregs, size_t size); + +/* Reads regsiters from the NT_ARC_V2 data array into the regcache. */ + +void arc_linux_supply_v2_regset (const struct regset *regset, + struct regcache *regcache, int regnum, + const void *v2_regs, size_t size); + +/* Writes registers from the regcache into the NT_PRSTATUS data array. */ + +void arc_linux_collect_gregset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *gregs, size_t size); + +/* Writes registers from the regcache into the NT_ARC_V2 data array. */ + +void arc_linux_collect_v2_regset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *v2_regs, size_t size); + +#endif /* ARC_LINUX_TDEP_H */ diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c index ec624bcbb9b..3b7a419dfc1 100644 --- a/gdb/arc-tdep.c +++ b/gdb/arc-tdep.c @@ -1883,10 +1883,9 @@ mach_type_to_arc_isa (const unsigned long mach) } } -/* Common construction code for ARC_ARCH_FEATURES struct. If there - is no ABFD, then a FEATURE with default values is returned. */ +/* See arc-tdep.h. */ -static arc_arch_features +arc_arch_features arc_arch_features_create (const bfd *abfd, const unsigned long mach) { /* Use 4 as a fallback value. */ diff --git a/gdb/arc-tdep.h b/gdb/arc-tdep.h index 6331d29f402..09fcbeab9c7 100644 --- a/gdb/arc-tdep.h +++ b/gdb/arc-tdep.h @@ -85,7 +85,9 @@ enum arc_regnum ARC_LP_END_REGNUM, /* Branch target address. */ ARC_BTA_REGNUM, - ARC_LAST_AUX_REGNUM = ARC_BTA_REGNUM, + /* Exception return address. */ + ARC_ERET_REGNUM, + ARC_LAST_AUX_REGNUM = ARC_ERET_REGNUM, ARC_LAST_REGNUM = ARC_LAST_AUX_REGNUM, /* Additional ABI constants. */ @@ -105,6 +107,9 @@ enum arc_regnum /* STATUS32 register: current instruction is a delay slot. */ #define ARC_STATUS32_DE_MASK (1 << 6) +/* Special value for register offset arrays. */ +#define ARC_OFFSET_NO_REGISTER (-1) + #define arc_print(fmt, args...) fprintf_unfiltered (gdb_stdlog, fmt, ##args) extern int arc_debug; @@ -182,4 +187,9 @@ CORE_ADDR arc_insn_get_branch_target (const struct arc_instruction &insn); CORE_ADDR arc_insn_get_linear_next_pc (const struct arc_instruction &insn); +/* Create an arc_arch_features instance from the provided data. */ + +arc_arch_features arc_arch_features_create (const bfd *abfd, + const unsigned long mach); + #endif /* ARC_TDEP_H */ -- 2.30.2