| /* Target-dependent code for GNU/Linux AArch64. |
| |
| Copyright (C) 2009-2013 Free Software Foundation, Inc. |
| Contributed by ARM Ltd. |
| |
| 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 "gdbarch.h" |
| #include "glibc-tdep.h" |
| #include "linux-tdep.h" |
| #include "aarch64-tdep.h" |
| #include "aarch64-linux-tdep.h" |
| #include "osabi.h" |
| #include "solib-svr4.h" |
| #include "symtab.h" |
| #include "tramp-frame.h" |
| #include "trad-frame.h" |
| |
| #include "inferior.h" |
| #include "regcache.h" |
| #include "regset.h" |
| |
| /* The general-purpose regset consists of 31 X registers, plus SP, PC, |
| and PSTATE registers, as defined in the AArch64 port of the Linux |
| kernel. */ |
| #define AARCH64_LINUX_SIZEOF_GREGSET (34 * X_REGISTER_SIZE) |
| |
| /* The fp regset consists of 32 V registers, plus FPCR and FPSR which |
| are 4 bytes wide each, and the whole structure is padded to 128 bit |
| alignment. */ |
| #define AARCH64_LINUX_SIZEOF_FPREGSET (33 * V_REGISTER_SIZE) |
| |
| /* Signal frame handling. |
| |
| +----------+ ^ |
| | saved lr | | |
| +->| saved fp |--+ |
| | | | |
| | | | |
| | +----------+ |
| | | saved lr | |
| +--| saved fp | |
| ^ | | |
| | | | |
| | +----------+ |
| ^ | | |
| | | signal | |
| | | | |
| | | saved lr |-->interrupted_function_pc |
| +--| saved fp | |
| | +----------+ |
| | | saved lr |--> default_restorer (movz x8, NR_sys_rt_sigreturn; svc 0) |
| +--| saved fp |<- FP |
| | | |
| | |<- SP |
| +----------+ |
| |
| On signal delivery, the kernel will create a signal handler stack |
| frame and setup the return address in LR to point at restorer stub. |
| The signal stack frame is defined by: |
| |
| struct rt_sigframe |
| { |
| siginfo_t info; |
| struct ucontext uc; |
| }; |
| |
| typedef struct |
| { |
| ... 128 bytes |
| } siginfo_t; |
| |
| The ucontext has the following form: |
| struct ucontext |
| { |
| unsigned long uc_flags; |
| struct ucontext *uc_link; |
| stack_t uc_stack; |
| sigset_t uc_sigmask; |
| struct sigcontext uc_mcontext; |
| }; |
| |
| typedef struct sigaltstack |
| { |
| void *ss_sp; |
| int ss_flags; |
| size_t ss_size; |
| } stack_t; |
| |
| struct sigcontext |
| { |
| unsigned long fault_address; |
| unsigned long regs[31]; |
| unsigned long sp; / * 31 * / |
| unsigned long pc; / * 32 * / |
| unsigned long pstate; / * 33 * / |
| __u8 __reserved[4096] |
| }; |
| |
| The restorer stub will always have the form: |
| |
| d28015a8 movz x8, #0xad |
| d4000001 svc #0x0 |
| |
| We detect signal frames by snooping the return code for the restorer |
| instruction sequence. |
| |
| The handler then needs to recover the saved register set from |
| ucontext.uc_mcontext. */ |
| |
| /* These magic numbers need to reflect the layout of the kernel |
| defined struct rt_sigframe and ucontext. */ |
| #define AARCH64_SIGCONTEXT_REG_SIZE 8 |
| #define AARCH64_RT_SIGFRAME_UCONTEXT_OFFSET 128 |
| #define AARCH64_UCONTEXT_SIGCONTEXT_OFFSET 176 |
| #define AARCH64_SIGCONTEXT_XO_OFFSET 8 |
| |
| /* Implement the "init" method of struct tramp_frame. */ |
| |
| static void |
| aarch64_linux_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); |
| CORE_ADDR sp = get_frame_register_unsigned (this_frame, AARCH64_SP_REGNUM); |
| CORE_ADDR fp = get_frame_register_unsigned (this_frame, AARCH64_FP_REGNUM); |
| CORE_ADDR sigcontext_addr = |
| sp |
| + AARCH64_RT_SIGFRAME_UCONTEXT_OFFSET |
| + AARCH64_UCONTEXT_SIGCONTEXT_OFFSET; |
| int i; |
| |
| for (i = 0; i < 31; i++) |
| { |
| trad_frame_set_reg_addr (this_cache, |
| AARCH64_X0_REGNUM + i, |
| sigcontext_addr + AARCH64_SIGCONTEXT_XO_OFFSET |
| + i * AARCH64_SIGCONTEXT_REG_SIZE); |
| } |
| |
| trad_frame_set_reg_addr (this_cache, AARCH64_FP_REGNUM, fp); |
| trad_frame_set_reg_addr (this_cache, AARCH64_LR_REGNUM, fp + 8); |
| trad_frame_set_reg_addr (this_cache, AARCH64_PC_REGNUM, fp + 8); |
| |
| trad_frame_set_id (this_cache, frame_id_build (fp, func)); |
| } |
| |
| static const struct tramp_frame aarch64_linux_rt_sigframe = |
| { |
| SIGTRAMP_FRAME, |
| 4, |
| { |
| /* movz x8, 0x8b (S=1,o=10,h=0,i=0x8b,r=8) |
| Soo1 0010 1hhi iiii iiii iiii iiir rrrr */ |
| {0xd2801168, -1}, |
| |
| /* svc 0x0 (o=0, l=1) |
| 1101 0100 oooi iiii iiii iiii iii0 00ll */ |
| {0xd4000001, -1}, |
| {TRAMP_SENTINEL_INSN, -1} |
| }, |
| aarch64_linux_sigframe_init |
| }; |
| |
| /* Fill GDB's register array with the general-purpose register values |
| in the buffer pointed by GREGS_BUF. */ |
| |
| void |
| aarch64_linux_supply_gregset (struct regcache *regcache, |
| const gdb_byte *gregs_buf) |
| { |
| int regno; |
| |
| for (regno = AARCH64_X0_REGNUM; regno <= AARCH64_CPSR_REGNUM; regno++) |
| regcache_raw_supply (regcache, regno, |
| gregs_buf + X_REGISTER_SIZE |
| * (regno - AARCH64_X0_REGNUM)); |
| } |
| |
| /* The "supply_regset" function for the general-purpose register set. */ |
| |
| static void |
| supply_gregset_from_core (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *regbuf, size_t len) |
| { |
| aarch64_linux_supply_gregset (regcache, (const gdb_byte *) regbuf); |
| } |
| |
| /* Fill GDB's register array with the floating-point register values |
| in the buffer pointed by FPREGS_BUF. */ |
| |
| void |
| aarch64_linux_supply_fpregset (struct regcache *regcache, |
| const gdb_byte *fpregs_buf) |
| { |
| int regno; |
| |
| for (regno = AARCH64_V0_REGNUM; regno <= AARCH64_V31_REGNUM; regno++) |
| regcache_raw_supply (regcache, regno, |
| fpregs_buf + V_REGISTER_SIZE |
| * (regno - AARCH64_V0_REGNUM)); |
| |
| regcache_raw_supply (regcache, AARCH64_FPSR_REGNUM, |
| fpregs_buf + V_REGISTER_SIZE * 32); |
| regcache_raw_supply (regcache, AARCH64_FPCR_REGNUM, |
| fpregs_buf + V_REGISTER_SIZE * 32 + 4); |
| } |
| |
| /* The "supply_regset" function for the floating-point register set. */ |
| |
| static void |
| supply_fpregset_from_core (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *regbuf, size_t len) |
| { |
| aarch64_linux_supply_fpregset (regcache, (const gdb_byte *) regbuf); |
| } |
| |
| /* Implement the "regset_from_core_section" gdbarch method. */ |
| |
| static const struct regset * |
| aarch64_linux_regset_from_core_section (struct gdbarch *gdbarch, |
| const char *sect_name, |
| size_t sect_size) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| if (strcmp (sect_name, ".reg") == 0 |
| && sect_size == AARCH64_LINUX_SIZEOF_GREGSET) |
| { |
| if (tdep->gregset == NULL) |
| tdep->gregset = regset_alloc (gdbarch, supply_gregset_from_core, |
| NULL); |
| return tdep->gregset; |
| } |
| |
| if (strcmp (sect_name, ".reg2") == 0 |
| && sect_size == AARCH64_LINUX_SIZEOF_FPREGSET) |
| { |
| if (tdep->fpregset == NULL) |
| tdep->fpregset = regset_alloc (gdbarch, supply_fpregset_from_core, |
| NULL); |
| return tdep->fpregset; |
| } |
| return NULL; |
| } |
| |
| static void |
| aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| tdep->lowest_pc = 0x8000; |
| |
| set_solib_svr4_fetch_link_map_offsets (gdbarch, |
| svr4_lp64_fetch_link_map_offsets); |
| |
| /* Enable TLS support. */ |
| set_gdbarch_fetch_tls_load_module_address (gdbarch, |
| svr4_fetch_objfile_link_map); |
| |
| /* Shared library handling. */ |
| set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
| |
| set_gdbarch_get_siginfo_type (gdbarch, linux_get_siginfo_type); |
| tramp_frame_prepend_unwinder (gdbarch, &aarch64_linux_rt_sigframe); |
| |
| /* Enable longjmp. */ |
| tdep->jb_pc = 11; |
| |
| set_gdbarch_regset_from_core_section (gdbarch, |
| aarch64_linux_regset_from_core_section); |
| } |
| |
| /* Provide a prototype to silence -Wmissing-prototypes. */ |
| extern initialize_file_ftype _initialize_aarch64_linux_tdep; |
| |
| void |
| _initialize_aarch64_linux_tdep (void) |
| { |
| gdbarch_register_osabi (bfd_arch_aarch64, 0, GDB_OSABI_LINUX, |
| aarch64_linux_init_abi); |
| } |