| /* Target-dependent code for FreeBSD/arm. |
| |
| Copyright (C) 2017-2021 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 "elf/common.h" |
| #include "target-descriptions.h" |
| #include "aarch32-tdep.h" |
| #include "arm-tdep.h" |
| #include "arm-fbsd-tdep.h" |
| #include "auxv.h" |
| #include "fbsd-tdep.h" |
| #include "gdbcore.h" |
| #include "osabi.h" |
| #include "solib-svr4.h" |
| #include "trad-frame.h" |
| #include "tramp-frame.h" |
| |
| /* Register maps. */ |
| |
| static const struct regcache_map_entry arm_fbsd_gregmap[] = |
| { |
| { 13, ARM_A1_REGNUM, 4 }, /* r0 ... r12 */ |
| { 1, ARM_SP_REGNUM, 4 }, |
| { 1, ARM_LR_REGNUM, 4 }, |
| { 1, ARM_PC_REGNUM, 4 }, |
| { 1, ARM_PS_REGNUM, 4 }, |
| { 0 } |
| }; |
| |
| static const struct regcache_map_entry arm_fbsd_vfpregmap[] = |
| { |
| { 32, ARM_D0_REGNUM, 8 }, /* d0 ... d31 */ |
| { 1, ARM_FPSCR_REGNUM, 4 }, |
| { 0 } |
| }; |
| |
| /* In a signal frame, sp points to a 'struct sigframe' which is |
| defined as: |
| |
| struct sigframe { |
| siginfo_t sf_si; |
| ucontext_t sf_uc; |
| mcontext_vfp_t sf_vfp; |
| }; |
| |
| ucontext_t is defined as: |
| |
| struct __ucontext { |
| sigset_t uc_sigmask; |
| mcontext_t uc_mcontext; |
| ... |
| }; |
| |
| mcontext_t is defined as: |
| |
| struct { |
| unsigned int __gregs[17]; |
| size_t mc_vfp_size; |
| void *mc_vfp_ptr; |
| ... |
| }; |
| |
| mcontext_vfp_t is defined as: |
| |
| struct { |
| uint64_t mcv_reg[32]; |
| uint32_t mcv_fpscr; |
| }; |
| |
| If the VFP state is valid, then mc_vfp_ptr will point to sf_vfp in |
| the sigframe, otherwise it is NULL. There is no non-VFP floating |
| point register state saved in the signal frame. */ |
| |
| #define ARM_SIGFRAME_UCONTEXT_OFFSET 64 |
| #define ARM_UCONTEXT_MCONTEXT_OFFSET 16 |
| #define ARM_MCONTEXT_VFP_PTR_OFFSET 72 |
| |
| /* Implement the "init" method of struct tramp_frame. */ |
| |
| static void |
| arm_fbsd_sigframe_init (const struct tramp_frame *self, |
| struct frame_info *this_frame, |
| struct trad_frame_cache *this_cache, |
| CORE_ADDR func) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| CORE_ADDR sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM); |
| CORE_ADDR mcontext_addr = (sp |
| + ARM_SIGFRAME_UCONTEXT_OFFSET |
| + ARM_UCONTEXT_MCONTEXT_OFFSET); |
| ULONGEST mcontext_vfp_addr; |
| |
| trad_frame_set_reg_regmap (this_cache, arm_fbsd_gregmap, mcontext_addr, |
| regcache_map_entry_size (arm_fbsd_gregmap)); |
| |
| if (safe_read_memory_unsigned_integer (mcontext_addr |
| + ARM_MCONTEXT_VFP_PTR_OFFSET, 4, |
| byte_order, |
| &mcontext_vfp_addr) |
| && mcontext_vfp_addr != 0) |
| trad_frame_set_reg_regmap (this_cache, arm_fbsd_vfpregmap, mcontext_vfp_addr, |
| regcache_map_entry_size (arm_fbsd_vfpregmap)); |
| |
| trad_frame_set_id (this_cache, frame_id_build (sp, func)); |
| } |
| |
| static const struct tramp_frame arm_fbsd_sigframe = |
| { |
| SIGTRAMP_FRAME, |
| 4, |
| { |
| {0xe1a0000d, ULONGEST_MAX}, /* mov r0, sp */ |
| {0xe2800040, ULONGEST_MAX}, /* add r0, r0, #SIGF_UC */ |
| {0xe59f700c, ULONGEST_MAX}, /* ldr r7, [pc, #12] */ |
| {0xef0001a1, ULONGEST_MAX}, /* swi SYS_sigreturn */ |
| {TRAMP_SENTINEL_INSN, ULONGEST_MAX} |
| }, |
| arm_fbsd_sigframe_init |
| }; |
| |
| /* Register set definitions. */ |
| |
| const struct regset arm_fbsd_gregset = |
| { |
| arm_fbsd_gregmap, |
| regcache_supply_regset, regcache_collect_regset |
| }; |
| |
| const struct regset arm_fbsd_vfpregset = |
| { |
| arm_fbsd_vfpregmap, |
| regcache_supply_regset, regcache_collect_regset |
| }; |
| |
| /* Implement the "iterate_over_regset_sections" gdbarch method. */ |
| |
| static void |
| arm_fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, |
| iterate_over_regset_sections_cb *cb, |
| void *cb_data, |
| const struct regcache *regcache) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| cb (".reg", ARM_FBSD_SIZEOF_GREGSET, ARM_FBSD_SIZEOF_GREGSET, |
| &arm_fbsd_gregset, NULL, cb_data); |
| |
| /* While FreeBSD/arm cores do contain a NT_FPREGSET / ".reg2" |
| register set, it is not populated with register values by the |
| kernel but just contains all zeroes. */ |
| if (tdep->vfp_register_count > 0) |
| cb (".reg-arm-vfp", ARM_FBSD_SIZEOF_VFPREGSET, ARM_FBSD_SIZEOF_VFPREGSET, |
| &arm_fbsd_vfpregset, "VFP floating-point", cb_data); |
| } |
| |
| /* Lookup a target description from a target's AT_HWCAP auxiliary |
| vector. */ |
| |
| const struct target_desc * |
| arm_fbsd_read_description_auxv (struct target_ops *target) |
| { |
| CORE_ADDR arm_hwcap = 0; |
| |
| if (target_auxv_search (target, AT_FREEBSD_HWCAP, &arm_hwcap) != 1) |
| return nullptr; |
| |
| if (arm_hwcap & HWCAP_VFP) |
| { |
| if (arm_hwcap & HWCAP_NEON) |
| return aarch32_read_description (); |
| else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPD32)) |
| == (HWCAP_VFPv3 | HWCAP_VFPD32)) |
| return arm_read_description (ARM_FP_TYPE_VFPV3); |
| else |
| return arm_read_description (ARM_FP_TYPE_VFPV2); |
| } |
| |
| return nullptr; |
| } |
| |
| /* Implement the "core_read_description" gdbarch method. */ |
| |
| static const struct target_desc * |
| arm_fbsd_core_read_description (struct gdbarch *gdbarch, |
| struct target_ops *target, |
| bfd *abfd) |
| { |
| return arm_fbsd_read_description_auxv (target); |
| } |
| |
| /* Implement the 'init_osabi' method of struct gdb_osabi_handler. */ |
| |
| static void |
| arm_fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| /* Generic FreeBSD support. */ |
| fbsd_init_abi (info, gdbarch); |
| |
| if (tdep->fp_model == ARM_FLOAT_AUTO) |
| tdep->fp_model = ARM_FLOAT_SOFT_VFP; |
| |
| tramp_frame_prepend_unwinder (gdbarch, &arm_fbsd_sigframe); |
| |
| set_solib_svr4_fetch_link_map_offsets |
| (gdbarch, svr4_ilp32_fetch_link_map_offsets); |
| |
| tdep->jb_pc = 24; |
| tdep->jb_elt_size = 4; |
| |
| set_gdbarch_iterate_over_regset_sections |
| (gdbarch, arm_fbsd_iterate_over_regset_sections); |
| set_gdbarch_core_read_description (gdbarch, arm_fbsd_core_read_description); |
| |
| /* Single stepping. */ |
| set_gdbarch_software_single_step (gdbarch, arm_software_single_step); |
| } |
| |
| void _initialize_arm_fbsd_tdep (); |
| void |
| _initialize_arm_fbsd_tdep () |
| { |
| gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_FREEBSD, |
| arm_fbsd_init_abi); |
| } |