CORE_ADDR
sol2_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
{
struct bound_minimal_symbol msym;
msym = lookup_minimal_symbol("elf_bndr", NULL, NULL);
if (msym.minsym && BMSYMBOL_VALUE_ADDRESS (msym) == pc)
return frame_unwind_caller_pc (get_current_frame ());
return 0;
}
CORE_ADDR
obsd_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
{
struct bound_minimal_symbol msym;
msym = lookup_minimal_symbol("_dl_bind", NULL, NULL);
if (msym.minsym && BMSYMBOL_VALUE_ADDRESS (msym) == pc)
return frame_unwind_caller_pc (get_current_frame ());
else
return find_solib_trampoline_target (get_current_frame (), pc);
}
static CORE_ADDR
tic6x_linux_syscall_next_pc (struct frame_info *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 CORE_ADDR
mips_linux_skip_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
{
struct minimal_symbol *resolver;
resolver = lookup_minimal_symbol ("__dl_runtime_resolve", NULL, NULL);
if (resolver && SYMBOL_VALUE_ADDRESS (resolver) == pc)
return frame_unwind_caller_pc (get_current_frame ());
return glibc_skip_solib_resolver (gdbarch, pc);
}
static CORE_ADDR
nios2_linux_syscall_next_pc (struct frame_info *frame)
{
CORE_ADDR pc = get_frame_pc (frame);
ULONGEST syscall_nr = get_frame_register_unsigned (frame, NIOS2_R2_REGNUM);
/* If we are about to make a sigreturn syscall, use the unwinder to
decode the signal frame. */
if (syscall_nr == 139 /* rt_sigreturn */)
return frame_unwind_caller_pc (frame);
return pc + NIOS2_OPCODE_SIZE;
}
static CORE_ADDR
mips_linux_syscall_next_pc (struct frame_info *frame)
{
CORE_ADDR pc = get_frame_pc (frame);
ULONGEST v0 = get_frame_register_unsigned (frame, MIPS_V0_REGNUM);
/* If we are about to make a sigreturn syscall, use the unwinder to
decode the signal frame. */
if (v0 == MIPS_NR_sigreturn
|| v0 == MIPS_NR_rt_sigreturn
|| v0 == MIPS_NR_N64_rt_sigreturn
|| v0 == MIPS_NR_N32_rt_sigreturn)
return frame_unwind_caller_pc (get_current_frame ());
return pc + 4;
}
/* Copy the value of next pc of sigreturn and rt_sigrturn into PC,
return 1. In addition, set IS_THUMB depending on whether we
will return to ARM or Thumb code. Return 0 if it is not a
rt_sigreturn/sigreturn syscall. */
static int
arm_linux_sigreturn_return_addr (struct frame_info *frame,
unsigned long svc_number,
CORE_ADDR *pc, int *is_thumb)
{
/* Is this a sigreturn or rt_sigreturn syscall? */
if (svc_number == 119 || svc_number == 173)
{
if (get_frame_type (frame) == SIGTRAMP_FRAME)
{
ULONGEST t_bit = arm_psr_thumb_bit (frame_unwind_arch (frame));
CORE_ADDR cpsr
= frame_unwind_register_unsigned (frame, ARM_PS_REGNUM);
*is_thumb = (cpsr & t_bit) != 0;
*pc = frame_unwind_caller_pc (frame);
return 1;
}
}
return 0;
}
static int
arm_linux_copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
struct regcache *regs, struct displaced_step_closure *dsc)
{
CORE_ADDR from = dsc->insn_addr;
struct frame_info *frame;
unsigned int svc_number = displaced_read_reg (regs, from, 7);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: copying Linux svc insn %.8lx\n",
(unsigned long) insn);
frame = get_current_frame ();
/* Is this a sigreturn or rt_sigreturn syscall? Note: these are only useful
for EABI. */
if (svc_number == 119 || svc_number == 173)
{
if (get_frame_type (frame) == SIGTRAMP_FRAME)
{
CORE_ADDR return_to;
struct symtab_and_line sal;
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: found "
"sigreturn/rt_sigreturn SVC call. PC in frame = %lx\n",
(unsigned long) get_frame_pc (frame));
return_to = frame_unwind_caller_pc (frame);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: unwind pc = %lx. "
"Setting momentary breakpoint.\n", (unsigned long) return_to);
gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
sal = find_pc_line (return_to, 0);
sal.pc = return_to;
sal.section = find_pc_overlay (return_to);
sal.explicit_pc = 1;
frame = get_prev_frame (frame);
if (frame)
{
inferior_thread ()->step_resume_breakpoint
= set_momentary_breakpoint (gdbarch, sal, get_frame_id (frame),
bp_step_resume);
/* We need to make sure we actually insert the momentary
breakpoint set above. */
insert_breakpoints ();
}
else if (debug_displaced)
fprintf_unfiltered (gdb_stderr, "displaced: couldn't find previous "
"frame to set momentary breakpoint for "
"sigreturn/rt_sigreturn\n");
}
else if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: sigreturn/rt_sigreturn "
"SVC call not in signal trampoline frame\n");
}
/* Preparation: If we detect sigreturn, set momentary breakpoint at resume
location, else nothing.
Insn: unmodified svc.
Cleanup: if pc lands in scratch space, pc <- insn_addr + 4
else leave pc alone. */
dsc->modinsn[0] = insn;
dsc->cleanup = &arm_linux_cleanup_svc;
/* Pretend we wrote to the PC, so cleanup doesn't set PC to the next
instruction. */
dsc->wrote_to_pc = 1;
return 0;
}
