static CORE_ADDR
alpha_linux_sigcontext_addr (struct frame_info *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;
}
static CORE_ADDR
alpha_linux_sigcontext_addr (struct frame_info *next_frame)
{
CORE_ADDR pc;
ULONGEST sp;
long off;
pc = frame_pc_unwind (next_frame);
frame_unwind_unsigned_register (next_frame, ALPHA_SP_REGNUM, &sp);
off = alpha_linux_sigtramp_offset (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 (pc - off + 4) == 0x201f015f)
return sp + 176;
/* __NR_sigreturn has the sigcontext structure at the top of the stack. */
return sp;
}
static int
alphaobsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
CORE_ADDR start_pc = (pc & ~(alphaobsd_page_size - 1));
unsigned insn;
if (name)
return 0;
/* Check for "". */
insn = alpha_read_insn (start_pc + 5 * ALPHA_INSN_SIZE);
if (insn != 0x201f0067)
return 0;
/* Check for "". */
insn = alpha_read_insn (start_pc + 6 * ALPHA_INSN_SIZE);
if (insn != 0x00000083)
return 0;
return 1;
}
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;
}
}
