| /* Target-dependent code for GNU/Linux on Alpha. |
| Copyright (C) 2002-2024 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 "frame.h" |
| #include "osabi.h" |
| #include "solib-svr4.h" |
| #include "symtab.h" |
| #include "regset.h" |
| #include "regcache.h" |
| #include "linux-tdep.h" |
| #include "alpha-tdep.h" |
| #include "gdbarch.h" |
| |
| /* This enum represents the signals' numbers on the Alpha |
| architecture. It just contains the signal definitions which are |
| different from the generic implementation. |
| |
| It is derived from the file <arch/alpha/include/uapi/asm/signal.h>, |
| from the Linux kernel tree. */ |
| |
| enum |
| { |
| /* SIGABRT is the same as in the generic implementation, but is |
| defined here because SIGIOT depends on it. */ |
| ALPHA_LINUX_SIGABRT = 6, |
| ALPHA_LINUX_SIGEMT = 7, |
| ALPHA_LINUX_SIGBUS = 10, |
| ALPHA_LINUX_SIGSYS = 12, |
| ALPHA_LINUX_SIGURG = 16, |
| ALPHA_LINUX_SIGSTOP = 17, |
| ALPHA_LINUX_SIGTSTP = 18, |
| ALPHA_LINUX_SIGCONT = 19, |
| ALPHA_LINUX_SIGCHLD = 20, |
| ALPHA_LINUX_SIGIO = 23, |
| ALPHA_LINUX_SIGINFO = 29, |
| ALPHA_LINUX_SIGUSR1 = 30, |
| ALPHA_LINUX_SIGUSR2 = 31, |
| ALPHA_LINUX_SIGPOLL = ALPHA_LINUX_SIGIO, |
| ALPHA_LINUX_SIGPWR = ALPHA_LINUX_SIGINFO, |
| ALPHA_LINUX_SIGIOT = ALPHA_LINUX_SIGABRT, |
| }; |
| |
| /* Under GNU/Linux, signal handler invocations can be identified by |
| the designated code sequence that is used to return from a signal |
| handler. In particular, the return address of a signal handler |
| points to a sequence that copies $sp to $16, loads $0 with the |
| appropriate syscall number, and finally enters the kernel. |
| |
| This is somewhat complicated in that: |
| (1) the expansion of the "mov" assembler macro has changed over |
| time, from "bis src,src,dst" to "bis zero,src,dst", |
| (2) the kernel has changed from using "addq" to "lda" to load the |
| syscall number, |
| (3) there is a "normal" sigreturn and an "rt" sigreturn which |
| has a different stack layout. */ |
| |
| static long |
| alpha_linux_sigtramp_offset_1 (struct gdbarch *gdbarch, CORE_ADDR pc) |
| { |
| switch (alpha_read_insn (gdbarch, pc)) |
| { |
| case 0x47de0410: /* bis $30,$30,$16 */ |
| case 0x47fe0410: /* bis $31,$30,$16 */ |
| return 0; |
| |
| case 0x43ecf400: /* addq $31,103,$0 */ |
| case 0x201f0067: /* lda $0,103($31) */ |
| case 0x201f015f: /* lda $0,351($31) */ |
| return 4; |
| |
| case 0x00000083: /* call_pal callsys */ |
| return 8; |
| |
| default: |
| return -1; |
| } |
| } |
| |
| static LONGEST |
| alpha_linux_sigtramp_offset (struct gdbarch *gdbarch, CORE_ADDR pc) |
| { |
| long i, off; |
| |
| if (pc & 3) |
| return -1; |
| |
| /* Guess where we might be in the sequence. */ |
| off = alpha_linux_sigtramp_offset_1 (gdbarch, pc); |
| if (off < 0) |
| return -1; |
| |
| /* Verify that the other two insns of the sequence are as we expect. */ |
| pc -= off; |
| for (i = 0; i < 12; i += 4) |
| { |
| if (i == off) |
| continue; |
| if (alpha_linux_sigtramp_offset_1 (gdbarch, pc + i) != i) |
| return -1; |
| } |
| |
| return off; |
| } |
| |
| static int |
| alpha_linux_pc_in_sigtramp (struct gdbarch *gdbarch, |
| CORE_ADDR pc, const char *func_name) |
| { |
| return alpha_linux_sigtramp_offset (gdbarch, pc) >= 0; |
| } |
| |
| static CORE_ADDR |
| alpha_linux_sigcontext_addr (const frame_info_ptr &this_frame) |
| { |
| struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| CORE_ADDR pc; |
| ULONGEST sp; |
| long off; |
| |
| pc = get_frame_pc (this_frame); |
| sp = get_frame_register_unsigned (this_frame, ALPHA_SP_REGNUM); |
| |
| off = alpha_linux_sigtramp_offset (gdbarch, pc); |
| gdb_assert (off >= 0); |
| |
| /* __NR_rt_sigreturn has a couple of structures on the stack. This is: |
| |
| struct rt_sigframe { |
| struct siginfo info; |
| struct ucontext uc; |
| }; |
| |
| offsetof (struct rt_sigframe, uc.uc_mcontext); */ |
| |
| if (alpha_read_insn (gdbarch, pc - off + 4) == 0x201f015f) |
| return sp + 176; |
| |
| /* __NR_sigreturn has the sigcontext structure at the top of the stack. */ |
| return sp; |
| } |
| |
| /* Supply register REGNUM from the buffer specified by GREGS and LEN |
| in the general-purpose register set REGSET to register cache |
| REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ |
| |
| static void |
| alpha_linux_supply_gregset (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *gregs, size_t len) |
| { |
| const gdb_byte *regs = (const gdb_byte *) gregs; |
| |
| gdb_assert (len >= 32 * 8); |
| alpha_supply_int_regs (regcache, regnum, regs, regs + 31 * 8, |
| len >= 33 * 8 ? regs + 32 * 8 : NULL); |
| } |
| |
| /* Collect register REGNUM from the register cache REGCACHE and store |
| it in the buffer specified by GREGS and LEN as described by the |
| general-purpose register set REGSET. If REGNUM is -1, do this for |
| all registers in REGSET. */ |
| |
| static void |
| alpha_linux_collect_gregset (const struct regset *regset, |
| const struct regcache *regcache, |
| int regnum, void *gregs, size_t len) |
| { |
| gdb_byte *regs = (gdb_byte *) gregs; |
| |
| gdb_assert (len >= 32 * 8); |
| alpha_fill_int_regs (regcache, regnum, regs, regs + 31 * 8, |
| len >= 33 * 8 ? regs + 32 * 8 : NULL); |
| } |
| |
| /* Supply register REGNUM from the buffer specified by FPREGS and LEN |
| in the floating-point register set REGSET to register cache |
| REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ |
| |
| static void |
| alpha_linux_supply_fpregset (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *fpregs, size_t len) |
| { |
| const gdb_byte *regs = (const gdb_byte *) fpregs; |
| |
| gdb_assert (len >= 32 * 8); |
| alpha_supply_fp_regs (regcache, regnum, regs, regs + 31 * 8); |
| } |
| |
| /* Collect register REGNUM from the register cache REGCACHE and store |
| it in the buffer specified by FPREGS and LEN as described by the |
| general-purpose register set REGSET. If REGNUM is -1, do this for |
| all registers in REGSET. */ |
| |
| static void |
| alpha_linux_collect_fpregset (const struct regset *regset, |
| const struct regcache *regcache, |
| int regnum, void *fpregs, size_t len) |
| { |
| gdb_byte *regs = (gdb_byte *) fpregs; |
| |
| gdb_assert (len >= 32 * 8); |
| alpha_fill_fp_regs (regcache, regnum, regs, regs + 31 * 8); |
| } |
| |
| static const struct regset alpha_linux_gregset = |
| { |
| NULL, |
| alpha_linux_supply_gregset, alpha_linux_collect_gregset |
| }; |
| |
| static const struct regset alpha_linux_fpregset = |
| { |
| NULL, |
| alpha_linux_supply_fpregset, alpha_linux_collect_fpregset |
| }; |
| |
| /* Iterate over core file register note sections. */ |
| |
| static void |
| alpha_linux_iterate_over_regset_sections (struct gdbarch *gdbarch, |
| iterate_over_regset_sections_cb *cb, |
| void *cb_data, |
| const struct regcache *regcache) |
| { |
| cb (".reg", 32 * 8, 32 * 8, &alpha_linux_gregset, NULL, cb_data); |
| cb (".reg2", 32 * 8, 32 * 8, &alpha_linux_fpregset, NULL, cb_data); |
| } |
| |
| /* Implementation of `gdbarch_gdb_signal_from_target', as defined in |
| gdbarch.h. */ |
| |
| static enum gdb_signal |
| alpha_linux_gdb_signal_from_target (struct gdbarch *gdbarch, |
| int signal) |
| { |
| switch (signal) |
| { |
| case ALPHA_LINUX_SIGEMT: |
| return GDB_SIGNAL_EMT; |
| |
| case ALPHA_LINUX_SIGBUS: |
| return GDB_SIGNAL_BUS; |
| |
| case ALPHA_LINUX_SIGSYS: |
| return GDB_SIGNAL_SYS; |
| |
| case ALPHA_LINUX_SIGURG: |
| return GDB_SIGNAL_URG; |
| |
| case ALPHA_LINUX_SIGSTOP: |
| return GDB_SIGNAL_STOP; |
| |
| case ALPHA_LINUX_SIGTSTP: |
| return GDB_SIGNAL_TSTP; |
| |
| case ALPHA_LINUX_SIGCONT: |
| return GDB_SIGNAL_CONT; |
| |
| case ALPHA_LINUX_SIGCHLD: |
| return GDB_SIGNAL_CHLD; |
| |
| /* No way to differentiate between SIGIO and SIGPOLL. |
| Therefore, we just handle the first one. */ |
| case ALPHA_LINUX_SIGIO: |
| return GDB_SIGNAL_IO; |
| |
| /* No way to differentiate between SIGINFO and SIGPWR. |
| Therefore, we just handle the first one. */ |
| case ALPHA_LINUX_SIGINFO: |
| return GDB_SIGNAL_INFO; |
| |
| case ALPHA_LINUX_SIGUSR1: |
| return GDB_SIGNAL_USR1; |
| |
| case ALPHA_LINUX_SIGUSR2: |
| return GDB_SIGNAL_USR2; |
| } |
| |
| return linux_gdb_signal_from_target (gdbarch, signal); |
| } |
| |
| /* Implementation of `gdbarch_gdb_signal_to_target', as defined in |
| gdbarch.h. */ |
| |
| static int |
| alpha_linux_gdb_signal_to_target (struct gdbarch *gdbarch, |
| enum gdb_signal signal) |
| { |
| switch (signal) |
| { |
| case GDB_SIGNAL_EMT: |
| return ALPHA_LINUX_SIGEMT; |
| |
| case GDB_SIGNAL_BUS: |
| return ALPHA_LINUX_SIGBUS; |
| |
| case GDB_SIGNAL_SYS: |
| return ALPHA_LINUX_SIGSYS; |
| |
| case GDB_SIGNAL_URG: |
| return ALPHA_LINUX_SIGURG; |
| |
| case GDB_SIGNAL_STOP: |
| return ALPHA_LINUX_SIGSTOP; |
| |
| case GDB_SIGNAL_TSTP: |
| return ALPHA_LINUX_SIGTSTP; |
| |
| case GDB_SIGNAL_CONT: |
| return ALPHA_LINUX_SIGCONT; |
| |
| case GDB_SIGNAL_CHLD: |
| return ALPHA_LINUX_SIGCHLD; |
| |
| case GDB_SIGNAL_IO: |
| return ALPHA_LINUX_SIGIO; |
| |
| case GDB_SIGNAL_INFO: |
| return ALPHA_LINUX_SIGINFO; |
| |
| case GDB_SIGNAL_USR1: |
| return ALPHA_LINUX_SIGUSR1; |
| |
| case GDB_SIGNAL_USR2: |
| return ALPHA_LINUX_SIGUSR2; |
| |
| case GDB_SIGNAL_POLL: |
| return ALPHA_LINUX_SIGPOLL; |
| |
| case GDB_SIGNAL_PWR: |
| return ALPHA_LINUX_SIGPWR; |
| } |
| |
| return linux_gdb_signal_to_target (gdbarch, signal); |
| } |
| |
| static void |
| alpha_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| linux_init_abi (info, gdbarch, 0); |
| |
| /* Hook into the DWARF CFI frame unwinder. */ |
| alpha_dwarf2_init_abi (info, gdbarch); |
| |
| /* Hook into the MDEBUG frame unwinder. */ |
| alpha_mdebug_init_abi (info, gdbarch); |
| |
| alpha_gdbarch_tdep *tdep = gdbarch_tdep<alpha_gdbarch_tdep> (gdbarch); |
| tdep->dynamic_sigtramp_offset = alpha_linux_sigtramp_offset; |
| tdep->sigcontext_addr = alpha_linux_sigcontext_addr; |
| tdep->pc_in_sigtramp = alpha_linux_pc_in_sigtramp; |
| tdep->jb_pc = 2; |
| tdep->jb_elt_size = 8; |
| |
| set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
| |
| set_solib_svr4_fetch_link_map_offsets |
| (gdbarch, linux_lp64_fetch_link_map_offsets); |
| |
| /* Enable TLS support. */ |
| set_gdbarch_fetch_tls_load_module_address (gdbarch, |
| svr4_fetch_objfile_link_map); |
| |
| set_gdbarch_iterate_over_regset_sections |
| (gdbarch, alpha_linux_iterate_over_regset_sections); |
| |
| set_gdbarch_gdb_signal_from_target (gdbarch, |
| alpha_linux_gdb_signal_from_target); |
| set_gdbarch_gdb_signal_to_target (gdbarch, |
| alpha_linux_gdb_signal_to_target); |
| } |
| |
| void _initialize_alpha_linux_tdep (); |
| void |
| _initialize_alpha_linux_tdep () |
| { |
| gdbarch_register_osabi (bfd_arch_alpha, 0, GDB_OSABI_LINUX, |
| alpha_linux_init_abi); |
| } |