diff options
Diffstat (limited to 'gdb/arm-netbsd-tdep.c')
| -rw-r--r-- | gdb/arm-netbsd-tdep.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/gdb/arm-netbsd-tdep.c b/gdb/arm-netbsd-tdep.c new file mode 100644 index 0000000..fa2e449 --- /dev/null +++ b/gdb/arm-netbsd-tdep.c @@ -0,0 +1,171 @@ +/* Target-dependent code for NetBSD/arm. + + Copyright (C) 2002-2020 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 <http://www.gnu.org/licenses/>. */ + +#include "defs.h" +#include "osabi.h" + +#include "arch/arm.h" +#include "arm-netbsd-tdep.h" +#include "netbsd-tdep.h" +#include "arm-tdep.h" +#include "regset.h" +#include "solib-svr4.h" + +/* Description of the longjmp buffer. */ +#define ARM_NBSD_JB_PC 24 +#define ARM_NBSD_JB_ELEMENT_SIZE ARM_INT_REGISTER_SIZE + +/* For compatibility with previous implementations of GDB on arm/NetBSD, + override the default little-endian breakpoint. */ +static const gdb_byte arm_nbsd_arm_le_breakpoint[] = {0x11, 0x00, 0x00, 0xe6}; +static const gdb_byte arm_nbsd_arm_be_breakpoint[] = {0xe6, 0x00, 0x00, 0x11}; +static const gdb_byte arm_nbsd_thumb_le_breakpoint[] = {0xfe, 0xde}; +static const gdb_byte arm_nbsd_thumb_be_breakpoint[] = {0xde, 0xfe}; + +/* This matches struct reg from NetBSD's sys/arch/arm/include/reg.h: + https://github.com/NetBSD/src/blob/7c13e6e6773bb171f4ed3ed53013e9d24b3c1eac/sys/arch/arm/include/reg.h#L39 + */ +struct arm_nbsd_reg +{ + uint32_t reg[13]; + uint32_t sp; + uint32_t lr; + uint32_t pc; + uint32_t cpsr; +}; + +void +arm_nbsd_supply_gregset (const struct regset *regset, struct regcache *regcache, + int regnum, const void *gregs, size_t len) +{ + const arm_nbsd_reg *gregset = static_cast<const arm_nbsd_reg *>(gregs); + gdb_assert (len >= sizeof (arm_nbsd_reg)); + + /* Integer registers. */ + for (int i = ARM_A1_REGNUM; i < ARM_SP_REGNUM; i++) + if (regnum == -1 || regnum == i) + regcache->raw_supply (i, (char *) &gregset->reg[i]); + + if (regnum == -1 || regnum == ARM_SP_REGNUM) + regcache->raw_supply (ARM_SP_REGNUM, (char *) &gregset->sp); + + if (regnum == -1 || regnum == ARM_LR_REGNUM) + regcache->raw_supply (ARM_LR_REGNUM, (char *) &gregset->lr); + + if (regnum == -1 || regnum == ARM_PC_REGNUM) + { + CORE_ADDR r_pc = gdbarch_addr_bits_remove (regcache->arch (), gregset->pc); + regcache->raw_supply (ARM_PC_REGNUM, (char *) &r_pc); + } + + if (regnum == -1 || regnum == ARM_PS_REGNUM) + { + if (arm_apcs_32) + regcache->raw_supply (ARM_PS_REGNUM, (char *) &gregset->cpsr); + else + regcache->raw_supply (ARM_PS_REGNUM, (char *) &gregset->pc); + } +} + +static const struct regset arm_nbsd_regset = { + nullptr, + arm_nbsd_supply_gregset, + /* We don't need a collect function because we only use this reading registers + (via iterate_over_regset_sections and fetch_regs/fetch_register). */ + nullptr, + 0 +}; + +static void +arm_nbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, + iterate_over_regset_sections_cb *cb, + void *cb_data, + const struct regcache *regcache) +{ + cb (".reg", sizeof (arm_nbsd_reg), sizeof (arm_nbsd_reg), &arm_nbsd_regset, + NULL, cb_data); + /* cbiesinger/2020-02-12 -- as far as I can tell, ARM/NetBSD does + not write any floating point registers into the core file (tested + with NetBSD 9.1_RC1). When it does, this function will need to read them, + and the arm-netbsd gdbarch will need a core_read_description function + to return the right description for them. */ +} + +static void +arm_netbsd_init_abi_common (struct gdbarch_info info, + struct gdbarch *gdbarch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + + tdep->lowest_pc = 0x8000; + switch (info.byte_order) + { + case BFD_ENDIAN_LITTLE: + tdep->arm_breakpoint = arm_nbsd_arm_le_breakpoint; + tdep->thumb_breakpoint = arm_nbsd_thumb_le_breakpoint; + tdep->arm_breakpoint_size = sizeof (arm_nbsd_arm_le_breakpoint); + tdep->thumb_breakpoint_size = sizeof (arm_nbsd_thumb_le_breakpoint); + break; + + case BFD_ENDIAN_BIG: + tdep->arm_breakpoint = arm_nbsd_arm_be_breakpoint; + tdep->thumb_breakpoint = arm_nbsd_thumb_be_breakpoint; + tdep->arm_breakpoint_size = sizeof (arm_nbsd_arm_be_breakpoint); + tdep->thumb_breakpoint_size = sizeof (arm_nbsd_thumb_be_breakpoint); + break; + + default: + internal_error (__FILE__, __LINE__, + _("arm_gdbarch_init: bad byte order for float format")); + } + + tdep->jb_pc = ARM_NBSD_JB_PC; + tdep->jb_elt_size = ARM_NBSD_JB_ELEMENT_SIZE; + + set_gdbarch_iterate_over_regset_sections + (gdbarch, arm_nbsd_iterate_over_regset_sections); + /* Single stepping. */ + set_gdbarch_software_single_step (gdbarch, arm_software_single_step); +} + +static void +arm_netbsd_elf_init_abi (struct gdbarch_info info, + struct gdbarch *gdbarch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + + arm_netbsd_init_abi_common (info, gdbarch); + + nbsd_init_abi (info, gdbarch); + + if (tdep->fp_model == ARM_FLOAT_AUTO) + tdep->fp_model = ARM_FLOAT_SOFT_VFP; + + /* NetBSD ELF uses SVR4-style shared libraries. */ + set_solib_svr4_fetch_link_map_offsets + (gdbarch, svr4_ilp32_fetch_link_map_offsets); +} + +void _initialize_arm_netbsd_tdep (); +void +_initialize_arm_netbsd_tdep () +{ + gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_NETBSD, + arm_netbsd_elf_init_abi); +} |