diff options
Diffstat (limited to 'gdb/arm-linux-tdep.c')
| -rw-r--r-- | gdb/arm-linux-tdep.c | 158 |
1 files changed, 96 insertions, 62 deletions
diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c index dd8f14b..93db35b 100644 --- a/gdb/arm-linux-tdep.c +++ b/gdb/arm-linux-tdep.c @@ -1,7 +1,7 @@ /* GNU/Linux on ARM target support. - Copyright (C) 1999, 2000, 2001, 2002, 2003, 2005 Free Software - Foundation, Inc. + Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005 + Free Software Foundation, Inc. This file is part of GDB. @@ -31,10 +31,14 @@ #include "doublest.h" #include "solib-svr4.h" #include "osabi.h" +#include "trad-frame.h" +#include "tramp-frame.h" #include "arm-tdep.h" #include "glibc-tdep.h" +#include "gdb_string.h" + /* Under ARM GNU/Linux the traditional way of performing a breakpoint is to execute a particular software interrupt, rather than use a particular undefined instruction to provoke a trap. Upon exection @@ -262,77 +266,98 @@ arm_linux_svr4_fetch_link_map_offsets (void) #define ARM_LINUX_SIGRETURN_INSTR 0xef900077 #define ARM_LINUX_RT_SIGRETURN_INSTR 0xef9000ad -/* arm_linux_in_sigtramp determines if PC points at one of the - instructions which cause control to return to the Linux kernel upon - return from a signal handler. FUNC_NAME is unused. */ +/* For ARM EABI, recognize the pattern that glibc uses... alternatively, + we could arrange to do this by function name, but they are not always + exported. */ +#define ARM_SET_R7_SIGRETURN 0xe3a07077 +#define ARM_SET_R7_RT_SIGRETURN 0xe3a070ad +#define ARM_EABI_SYSCALL 0xef000000 -int -arm_linux_in_sigtramp (CORE_ADDR pc, char *func_name) +static void +arm_linux_sigtramp_cache (struct frame_info *next_frame, + struct trad_frame_cache *this_cache, + CORE_ADDR func, int regs_offset) { - unsigned long inst; + CORE_ADDR sp = frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM); + CORE_ADDR base = sp + regs_offset; + int i; - inst = read_memory_integer (pc, 4); + for (i = 0; i < 16; i++) + trad_frame_set_reg_addr (this_cache, i, base + i * 4); - return (inst == ARM_LINUX_SIGRETURN_INSTR - || inst == ARM_LINUX_RT_SIGRETURN_INSTR); + trad_frame_set_reg_addr (this_cache, ARM_PS_REGNUM, base + 16 * 4); -} + /* The VFP or iWMMXt registers may be saved on the stack, but there's + no reliable way to restore them (yet). */ -/* arm_linux_sigcontext_register_address returns the address in the - sigcontext of register REGNO given a stack pointer value SP and - program counter value PC. The value 0 is returned if PC is not - pointing at one of the signal return instructions or if REGNO is - not saved in the sigcontext struct. */ + /* Save a frame ID. */ + trad_frame_set_id (this_cache, frame_id_build (sp, func)); +} -CORE_ADDR -arm_linux_sigcontext_register_address (CORE_ADDR sp, CORE_ADDR pc, int regno) +static void +arm_linux_sigreturn_init (const struct tramp_frame *self, + struct frame_info *next_frame, + struct trad_frame_cache *this_cache, + CORE_ADDR func) { - unsigned long inst; - CORE_ADDR reg_addr = 0; - - inst = read_memory_integer (pc, 4); - - if (inst == ARM_LINUX_SIGRETURN_INSTR - || inst == ARM_LINUX_RT_SIGRETURN_INSTR) - { - CORE_ADDR sigcontext_addr; - - /* The sigcontext structure is at different places for the two - signal return instructions. For ARM_LINUX_SIGRETURN_INSTR, - it starts at the SP value. For ARM_LINUX_RT_SIGRETURN_INSTR, - it is at SP+8. For the latter instruction, it may also be - the case that the address of this structure may be determined - by reading the 4 bytes at SP, but I'm not convinced this is - reliable. - - In any event, these magic constants (0 and 8) may be - determined by examining struct sigframe and struct - rt_sigframe in arch/arm/kernel/signal.c in the Linux kernel - sources. */ - - if (inst == ARM_LINUX_RT_SIGRETURN_INSTR) - sigcontext_addr = sp + 8; - else /* inst == ARM_LINUX_SIGRETURN_INSTR */ - sigcontext_addr = sp + 0; - - /* The layout of the sigcontext structure for ARM GNU/Linux is - in include/asm-arm/sigcontext.h in the Linux kernel sources. - - There are three 4-byte fields which precede the saved r0 - field. (This accounts for the 12 in the code below.) The - sixteen registers (4 bytes per field) follow in order. The - PSR value follows the sixteen registers which accounts for - the constant 19 below. */ - - if (0 <= regno && regno <= ARM_PC_REGNUM) - reg_addr = sigcontext_addr + 12 + (4 * regno); - else if (regno == ARM_PS_REGNUM) - reg_addr = sigcontext_addr + 19 * 4; - } + arm_linux_sigtramp_cache (next_frame, this_cache, func, + 0x0c /* Offset to registers. */); +} - return reg_addr; +static void +arm_linux_rt_sigreturn_init (const struct tramp_frame *self, + struct frame_info *next_frame, + struct trad_frame_cache *this_cache, + CORE_ADDR func) +{ + arm_linux_sigtramp_cache (next_frame, this_cache, func, + 0x88 /* Offset to ucontext_t. */ + + 0x14 /* Offset to sigcontext. */ + + 0x0c /* Offset to registers. */); } +static struct tramp_frame arm_linux_sigreturn_tramp_frame = { + SIGTRAMP_FRAME, + 4, + { + { ARM_LINUX_SIGRETURN_INSTR, -1 }, + { TRAMP_SENTINEL_INSN } + }, + arm_linux_sigreturn_init +}; + +static struct tramp_frame arm_linux_rt_sigreturn_tramp_frame = { + SIGTRAMP_FRAME, + 4, + { + { ARM_LINUX_RT_SIGRETURN_INSTR, -1 }, + { TRAMP_SENTINEL_INSN } + }, + arm_linux_rt_sigreturn_init +}; + +static struct tramp_frame arm_eabi_linux_sigreturn_tramp_frame = { + SIGTRAMP_FRAME, + 4, + { + { ARM_SET_R7_SIGRETURN, -1 }, + { ARM_EABI_SYSCALL, -1 }, + { TRAMP_SENTINEL_INSN } + }, + arm_linux_sigreturn_init +}; + +static struct tramp_frame arm_eabi_linux_rt_sigreturn_tramp_frame = { + SIGTRAMP_FRAME, + 4, + { + { ARM_SET_R7_RT_SIGRETURN, -1 }, + { ARM_EABI_SYSCALL, -1 }, + { TRAMP_SENTINEL_INSN } + }, + arm_linux_rt_sigreturn_init +}; + static void arm_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) @@ -378,6 +403,15 @@ arm_linux_init_abi (struct gdbarch_info info, /* Enable TLS support. */ set_gdbarch_fetch_tls_load_module_address (gdbarch, svr4_fetch_objfile_link_map); + + tramp_frame_prepend_unwinder (gdbarch, + &arm_linux_sigreturn_tramp_frame); + tramp_frame_prepend_unwinder (gdbarch, + &arm_linux_rt_sigreturn_tramp_frame); + tramp_frame_prepend_unwinder (gdbarch, + &arm_eabi_linux_sigreturn_tramp_frame); + tramp_frame_prepend_unwinder (gdbarch, + &arm_eabi_linux_rt_sigreturn_tramp_frame); } void |