x86-64-linux-tdep.c [plain text]
#include "defs.h"
#include "inferior.h"
#include "gdbcore.h"
#include "gdb_string.h"
#include "regcache.h"
#include "x86-64-tdep.h"
#include "dwarf2cfi.h"
#include "osabi.h"
#define LINUX_SIGTRAMP_INSN0 (0x48)
#define LINUX_SIGTRAMP_OFFSET0 (0)
#define LINUX_SIGTRAMP_INSN1 (0x0f)
#define LINUX_SIGTRAMP_OFFSET1 (7)
static const unsigned char linux_sigtramp_code[] = {
LINUX_SIGTRAMP_INSN0, 0xc7, 0xc0, 0x0f, 0x00, 0x00, 0x00,
LINUX_SIGTRAMP_INSN1, 0x05
};
#define LINUX_SIGTRAMP_LEN (sizeof linux_sigtramp_code)
static CORE_ADDR
x86_64_linux_sigtramp_start (CORE_ADDR pc)
{
unsigned char buf[LINUX_SIGTRAMP_LEN];
if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
return 0;
if (buf[0] != LINUX_SIGTRAMP_INSN0)
{
if (buf[0] != LINUX_SIGTRAMP_INSN1)
return 0;
pc -= LINUX_SIGTRAMP_OFFSET1;
if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
return 0;
}
if (memcmp (buf, linux_sigtramp_code, LINUX_SIGTRAMP_LEN) != 0)
return 0;
return pc;
}
#define LINUX_SIGINFO_SIZE 0
#define LINUX_UCONTEXT_SIGCONTEXT_OFFSET 40
#define LINUX_SIGCONTEXT_PC_OFFSET 128
#define LINUX_SIGCONTEXT_FP_OFFSET 120
static CORE_ADDR
x86_64_linux_sigcontext_addr (struct frame_info *frame)
{
CORE_ADDR pc;
ULONGEST rsp;
pc = x86_64_linux_sigtramp_start (get_frame_pc (frame));
if (pc)
{
if (get_next_frame (frame))
return get_frame_base (get_next_frame (frame)) + LINUX_SIGINFO_SIZE +
LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
rsp = read_register (SP_REGNUM);
return rsp + LINUX_SIGINFO_SIZE + LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
}
error ("Couldn't recognize signal trampoline.");
return 0;
}
static CORE_ADDR
x86_64_linux_sigtramp_saved_pc (struct frame_info *frame)
{
CORE_ADDR addr;
addr = x86_64_linux_sigcontext_addr (frame);
return read_memory_integer (addr + LINUX_SIGCONTEXT_PC_OFFSET, 8);
}
CORE_ADDR
x86_64_linux_saved_pc_after_call (struct frame_info *frame)
{
if ((get_frame_type (frame) == SIGTRAMP_FRAME))
return x86_64_linux_sigtramp_saved_pc (frame);
return read_memory_integer (read_register (SP_REGNUM), 8);
}
CORE_ADDR
x86_64_linux_frame_saved_pc (struct frame_info *frame)
{
if ((get_frame_type (frame) == SIGTRAMP_FRAME))
return x86_64_linux_sigtramp_saved_pc (frame);
return cfi_get_ra (frame);
}
int
x86_64_linux_in_sigtramp (CORE_ADDR pc, char *name)
{
if (name)
return strcmp ("__restore_rt", name) == 0;
return (x86_64_linux_sigtramp_start (pc) != 0);
}
CORE_ADDR
x86_64_linux_frame_chain (struct frame_info *fi)
{
ULONGEST addr;
CORE_ADDR fp, pc;
if (!(get_frame_type (fi) == SIGTRAMP_FRAME))
{
fp = cfi_frame_chain (fi);
if (fp)
return fp;
else
addr = get_frame_base (fi);
}
else
addr = get_frame_base (get_next_frame (fi));
addr += LINUX_SIGINFO_SIZE + LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
fp = read_memory_integer (addr + LINUX_SIGCONTEXT_FP_OFFSET, 8) + 8;
return fp;
}
CORE_ADDR
x86_64_init_frame_pc (int fromleaf, struct frame_info *fi)
{
CORE_ADDR addr;
if (get_next_frame (fi)
&& (get_frame_type (get_next_frame (fi)) == SIGTRAMP_FRAME))
{
addr = get_frame_base (get_next_frame (get_next_frame (fi)))
+ LINUX_SIGINFO_SIZE + LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
return read_memory_integer (addr + LINUX_SIGCONTEXT_PC_OFFSET, 8);
}
else
return cfi_init_frame_pc (fromleaf, fi);
}
static void
x86_64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
x86_64_init_abi (info, gdbarch);
}
extern void _initialize_x86_64_linux_tdep (void);
void
_initialize_x86_64_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, GDB_OSABI_LINUX,
x86_64_linux_init_abi);
}