| /* GNU/Linux on TI C6x target support. |
| Copyright (C) 2011-2024 Free Software Foundation, Inc. |
| Contributed by Yao Qi <yao@codesourcery.com> |
| |
| 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 "solib.h" |
| #include "osabi.h" |
| #include "linux-tdep.h" |
| #include "tic6x-tdep.h" |
| #include "trad-frame.h" |
| #include "tramp-frame.h" |
| #include "elf-bfd.h" |
| #include "elf/tic6x.h" |
| #include "gdbarch.h" |
| #include "solib-dsbt.h" |
| |
| /* The offset from rt_sigframe pointer to SP register. */ |
| #define TIC6X_SP_RT_SIGFRAME 8 |
| /* Size of struct siginfo info. */ |
| #define TIC6X_SIGINFO_SIZE 128 |
| /* Size of type stack_t, which contains three fields of type void*, int, and |
| size_t respectively. */ |
| #define TIC6X_STACK_T_SIZE (3 * 4) |
| |
| static const gdb_byte tic6x_bkpt_bnop_be[] = { 0x00, 0x00, 0xa1, 0x22 }; |
| static const gdb_byte tic6x_bkpt_bnop_le[] = { 0x22, 0xa1, 0x00, 0x00 }; |
| |
| /* Return the offset of register REGNUM in struct sigcontext. Return 0 if no |
| such register in sigcontext. */ |
| |
| static unsigned int |
| tic6x_register_sigcontext_offset (unsigned int regnum, struct gdbarch *gdbarch) |
| { |
| tic6x_gdbarch_tdep *tdep = gdbarch_tdep<tic6x_gdbarch_tdep> (gdbarch); |
| |
| if (regnum == TIC6X_A4_REGNUM || regnum == TIC6X_A4_REGNUM + 2 |
| || regnum == TIC6X_A4_REGNUM + 4) |
| return 4 * (regnum - TIC6X_A4_REGNUM + 2); /* A4, A6, A8 */ |
| else if (regnum == TIC6X_A5_REGNUM || regnum == TIC6X_A5_REGNUM + 2 |
| || regnum == TIC6X_A5_REGNUM + 4) |
| return 4 * (regnum - TIC6X_A5_REGNUM + 12); /* A5, A7, A9 */ |
| else if (regnum == TIC6X_B4_REGNUM || regnum == TIC6X_B4_REGNUM + 2 |
| || regnum == TIC6X_B4_REGNUM + 4) |
| return 4 * (regnum - TIC6X_B4_REGNUM + 3); /* B4, B6, B8 */ |
| else if (regnum == TIC6X_B5_REGNUM || regnum == TIC6X_B5_REGNUM + 2 |
| || regnum == TIC6X_B5_REGNUM + 4) |
| return 4 * (regnum - TIC6X_B5_REGNUM + 19); /* B5, B7, B9 */ |
| else if (regnum < TIC6X_A4_REGNUM) |
| return 4 * (regnum - 0 + 8); /* A0 - A3 */ |
| else if (regnum >= TIC6X_B0_REGNUM && regnum < TIC6X_B4_REGNUM) |
| return 4 * (regnum - TIC6X_B0_REGNUM + 15); /* B0 - B3 */ |
| else if (regnum >= 34 && regnum < 34 + 32) |
| return 4 * (regnum - 34 + 23); /* A16 - A31, B16 - B31 */ |
| else if (regnum == TIC6X_PC_REGNUM) |
| return 4 * (tdep->has_gp ? 55 : 23); |
| else if (regnum == TIC6X_SP_REGNUM) |
| return 4; |
| |
| return 0; |
| } |
| |
| /* Support unwinding frame in signal trampoline. We don't check sigreturn, |
| since it is not used in kernel. */ |
| |
| static void |
| tic6x_linux_rt_sigreturn_init (const struct tramp_frame *self, |
| const frame_info_ptr &this_frame, |
| struct trad_frame_cache *this_cache, |
| CORE_ADDR func) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| CORE_ADDR sp = get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM); |
| /* The base of struct sigcontext is computed by examining the definition of |
| struct rt_sigframe in linux kernel source arch/c6x/kernel/signal.c. */ |
| CORE_ADDR base = (sp + TIC6X_SP_RT_SIGFRAME |
| /* Pointer type *pinfo and *puc in struct rt_sigframe. */ |
| + 4 + 4 |
| + TIC6X_SIGINFO_SIZE |
| + 4 + 4 /* uc_flags and *uc_link in struct ucontext. */ |
| + TIC6X_STACK_T_SIZE); |
| tic6x_gdbarch_tdep *tdep = gdbarch_tdep<tic6x_gdbarch_tdep> (gdbarch); |
| unsigned int reg_offset; |
| unsigned int i; |
| |
| for (i = 0; i < 10; i++) /* A0 - A9 */ |
| { |
| reg_offset = tic6x_register_sigcontext_offset (i, gdbarch); |
| gdb_assert (reg_offset != 0); |
| |
| trad_frame_set_reg_addr (this_cache, i, base + reg_offset); |
| } |
| |
| for (i = TIC6X_B0_REGNUM; i < TIC6X_B0_REGNUM + 10; i++) /* B0 - B9 */ |
| { |
| reg_offset = tic6x_register_sigcontext_offset (i, gdbarch); |
| gdb_assert (reg_offset != 0); |
| |
| trad_frame_set_reg_addr (this_cache, i, base + reg_offset); |
| } |
| |
| if (tdep->has_gp) |
| for (i = 34; i < 34 + 32; i++) /* A16 - A31, B16 - B31 */ |
| { |
| reg_offset = tic6x_register_sigcontext_offset (i, gdbarch); |
| gdb_assert (reg_offset != 0); |
| |
| trad_frame_set_reg_addr (this_cache, i, base + reg_offset); |
| } |
| |
| trad_frame_set_reg_addr (this_cache, TIC6X_PC_REGNUM, |
| base + tic6x_register_sigcontext_offset (TIC6X_PC_REGNUM, |
| gdbarch)); |
| trad_frame_set_reg_addr (this_cache, TIC6X_SP_REGNUM, |
| base + tic6x_register_sigcontext_offset (TIC6X_SP_REGNUM, |
| gdbarch)); |
| |
| /* Save a frame ID. */ |
| trad_frame_set_id (this_cache, frame_id_build (sp, func)); |
| } |
| |
| static struct tramp_frame tic6x_linux_rt_sigreturn_tramp_frame = |
| { |
| SIGTRAMP_FRAME, |
| 4, |
| { |
| {0x000045aa, 0x0fffffff}, /* mvk .S2 139,b0 */ |
| {0x10000000, ULONGEST_MAX}, /* swe */ |
| {TRAMP_SENTINEL_INSN} |
| }, |
| tic6x_linux_rt_sigreturn_init |
| }; |
| |
| /* When FRAME is at a syscall instruction, return the PC of the next |
| instruction to be executed. */ |
| |
| static CORE_ADDR |
| tic6x_linux_syscall_next_pc (const frame_info_ptr &frame) |
| { |
| ULONGEST syscall_number = get_frame_register_unsigned (frame, |
| TIC6X_B0_REGNUM); |
| CORE_ADDR pc = get_frame_pc (frame); |
| |
| if (syscall_number == 139 /* rt_sigreturn */) |
| return frame_unwind_caller_pc (frame); |
| |
| return pc + 4; |
| } |
| |
| |
| static void |
| tic6x_uclinux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| tic6x_gdbarch_tdep *tdep = gdbarch_tdep<tic6x_gdbarch_tdep> (gdbarch); |
| |
| linux_init_abi (info, gdbarch, 0); |
| |
| /* Shared library handling. */ |
| set_gdbarch_so_ops (gdbarch, &dsbt_so_ops); |
| |
| tdep->syscall_next_pc = tic6x_linux_syscall_next_pc; |
| |
| #ifdef HAVE_ELF |
| /* In tic6x Linux kernel, breakpoint instructions varies on different archs. |
| On C64x+ and C67x+, breakpoint instruction is 0x56454314, which is an |
| illegal opcode. On other arch, breakpoint instruction is 0x0000a122 |
| (BNOP .S2 0,5). */ |
| if (info.abfd) |
| switch (bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, Tag_ISA)) |
| { |
| case C6XABI_Tag_ISA_C64XP: |
| case C6XABI_Tag_ISA_C67XP: |
| if (info.byte_order == BFD_ENDIAN_BIG) |
| tdep->breakpoint = tic6x_bkpt_illegal_opcode_be; |
| else |
| tdep->breakpoint = tic6x_bkpt_illegal_opcode_le; |
| break; |
| default: |
| { |
| if (info.byte_order == BFD_ENDIAN_BIG) |
| tdep->breakpoint = tic6x_bkpt_bnop_be; |
| else |
| tdep->breakpoint = tic6x_bkpt_bnop_le; |
| } |
| } |
| #endif |
| |
| /* Signal trampoline support. */ |
| tramp_frame_prepend_unwinder (gdbarch, |
| &tic6x_linux_rt_sigreturn_tramp_frame); |
| } |
| |
| void _initialize_tic6x_linux_tdep (); |
| void |
| _initialize_tic6x_linux_tdep () |
| { |
| gdbarch_register_osabi (bfd_arch_tic6x, 0, GDB_OSABI_LINUX, |
| tic6x_uclinux_init_abi); |
| } |