old-cross-binutils/gdb/frv-linux-tdep.c
Kevin Buettner 5ecb7103b5 * Makefile.in (frv-linux-tdep.o): Add dependencies.
* frv-linux-tdep.c: New file.
	* frv-tdep.c (struct gdbarch_tdep): Add new field
	``sigcontext_reg_addr''.
	(frv_set_sigcontext_reg_addr, frv_sigtramp,frame_cache)
	(frv_sigtramp_frame_this_id, frv_sigtramp_frame_prev_register)
	(frv_sigramp_frame_sniffer): New functions.
	(frv_sigtramp_frame_unwind): New static global.
	(frv_gdbarch_init): Hook in ABI-specific overrides.  Hook up frame
	sniffers.
	* frv-tdep.h (frv_set_sigcontext_reg_addr): New function.
	* config/frv/frv.mt (TDEPFILES): Add frv-linux-tdep.o.
2004-03-15 19:42:25 +00:00

273 lines
7.5 KiB
C

/* Target-dependent code for GNU/Linux running on the Fujitsu FR-V,
for GDB.
Copyright 2004 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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "target.h"
#include "frame.h"
#include "osabi.h"
#include "elf-bfd.h"
#include "elf/frv.h"
#include "frv-tdep.h"
/* Define the size (in bytes) of an FR-V instruction. */
static const int frv_instr_size = 4;
enum {
NORMAL_SIGTRAMP = 1,
RT_SIGTRAMP = 2
};
static int
frv_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
char buf[frv_instr_size];
LONGEST instr;
int retval = 0;
if (target_read_memory (pc, buf, sizeof buf) != 0)
return 0;
instr = extract_unsigned_integer (buf, sizeof buf);
if (instr == 0x8efc0077) /* setlos #__NR_sigreturn, gr7 */
retval = NORMAL_SIGTRAMP;
else if (instr -= 0x8efc00ad) /* setlos #__NR_rt_sigreturn, gr7 */
retval = RT_SIGTRAMP;
else
return 0;
if (target_read_memory (pc + frv_instr_size, buf, sizeof buf) != 0)
return 0;
instr = extract_unsigned_integer (buf, sizeof buf);
if (instr != 0xc0700000) /* tira gr0, 0 */
return 0;
/* If we get this far, we'll return a non-zero value, either
NORMAL_SIGTRAMP (1) or RT_SIGTRAMP (2). */
return retval;
}
/* Given NEXT_FRAME, "callee" frame of the sigtramp frame that we
wish to decode, and REGNO, one of the frv register numbers defined
in frv-tdep.h, return the address of the saved register (corresponding
to REGNO) in the sigtramp frame. Return -1 if the register is not
found in the sigtramp frame. The magic numbers in the code below
were computed by examining the following kernel structs:
From arch/frvnommu/signal.c:
struct sigframe
{
void (*pretcode)(void);
int sig;
struct sigcontext sc;
unsigned long extramask[_NSIG_WORDS-1];
uint32_t retcode[2];
};
struct rt_sigframe
{
void (*pretcode)(void);
int sig;
struct siginfo *pinfo;
void *puc;
struct siginfo info;
struct ucontext uc;
uint32_t retcode[2];
};
From include/asm-frvnommu/ucontext.h:
struct ucontext {
unsigned long uc_flags;
struct ucontext *uc_link;
stack_t uc_stack;
struct sigcontext uc_mcontext;
sigset_t uc_sigmask;
};
From include/asm-frvnommu/sigcontext.h:
struct sigcontext {
struct user_context sc_context;
unsigned long sc_oldmask;
} __attribute__((aligned(8)));
From include/asm-frvnommu/registers.h:
struct user_int_regs
{
unsigned long psr;
unsigned long isr;
unsigned long ccr;
unsigned long cccr;
unsigned long lr;
unsigned long lcr;
unsigned long pc;
unsigned long __status;
unsigned long syscallno;
unsigned long orig_gr8;
unsigned long gner[2];
unsigned long long iacc[1];
union {
unsigned long tbr;
unsigned long gr[64];
};
};
struct user_fpmedia_regs
{
unsigned long fr[64];
unsigned long fner[2];
unsigned long msr[2];
unsigned long acc[8];
unsigned char accg[8];
unsigned long fsr[1];
};
struct user_context
{
struct user_int_regs i;
struct user_fpmedia_regs f;
void *extension;
} __attribute__((aligned(8))); */
static CORE_ADDR
frv_linux_sigcontext_reg_addr (struct frame_info *next_frame, int regno,
CORE_ADDR *sc_addr_cache_ptr)
{
CORE_ADDR sc_addr;
if (sc_addr_cache_ptr && *sc_addr_cache_ptr)
{
sc_addr = *sc_addr_cache_ptr;
}
else
{
CORE_ADDR pc, sp;
char buf[4];
int tramp_type;
pc = frame_pc_unwind (next_frame);
tramp_type = frv_linux_pc_in_sigtramp (pc, 0);
frame_unwind_register (next_frame, sp_regnum, buf);
sp = extract_unsigned_integer (buf, sizeof buf);
if (tramp_type == NORMAL_SIGTRAMP)
{
/* For a normal sigtramp frame, the sigcontext struct starts
at SP + 8. */
sc_addr = sp + 8;
}
else if (tramp_type == RT_SIGTRAMP)
{
/* For a realtime sigtramp frame, SP + 12 contains a pointer
to the a ucontext struct. The ucontext struct contains
a sigcontext struct starting 12 bytes in. */
if (target_read_memory (sp + 12, buf, sizeof buf) != 0)
{
warning ("Can't read realtime sigtramp frame.");
return 0;
}
sc_addr = extract_unsigned_integer (buf, sizeof buf);
sc_addr += 12;
}
else
internal_error (__FILE__, __LINE__, "not a signal trampoline");
if (sc_addr_cache_ptr)
*sc_addr_cache_ptr = sc_addr;
}
switch (regno)
{
case psr_regnum :
return sc_addr + 0;
/* sc_addr + 4 has "isr", the Integer Status Register. */
case ccr_regnum :
return sc_addr + 8;
case cccr_regnum :
return sc_addr + 12;
case lr_regnum :
return sc_addr + 16;
case lcr_regnum :
return sc_addr + 20;
case pc_regnum :
return sc_addr + 24;
/* sc_addr + 28 is __status, the exception status.
sc_addr + 32 is syscallno, the syscall number or -1.
sc_addr + 36 is orig_gr8, the original syscall arg #1.
sc_addr + 40 is gner[0].
sc_addr + 44 is gner[1]. */
case iacc0h_regnum :
return sc_addr + 48;
case iacc0l_regnum :
return sc_addr + 52;
default :
if (first_gpr_regnum <= regno && regno <= last_gpr_regnum)
return sc_addr + 56 + 4 * (regno - first_gpr_regnum);
else if (first_fpr_regnum <= regno && regno <= last_fpr_regnum)
return sc_addr + 312 + 4 * (regno - first_fpr_regnum);
else
return -1; /* not saved. */
}
}
static void
frv_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
/* When the FR-V Linux kernel calls a signal handler, the return
address points to a bit of code on the stack. This function is
used to identify this bit of code as a signal trampoline in order
to support backtracing through calls to signal handlers. */
set_gdbarch_pc_in_sigtramp (gdbarch, frv_linux_pc_in_sigtramp);
frv_set_sigcontext_reg_addr (gdbarch, frv_linux_sigcontext_reg_addr);
}
static enum gdb_osabi
frv_linux_elf_osabi_sniffer (bfd *abfd)
{
int elf_flags;
elf_flags = elf_elfheader (abfd)->e_flags;
/* Assume GNU/Linux if using the FDPIC ABI. If/when another OS shows
up that uses this ABI, we'll need to start using .note sections
or some such. */
if (elf_flags & EF_FRV_FDPIC)
return GDB_OSABI_LINUX;
else
return GDB_OSABI_UNKNOWN;
}
/* Provide a prototype to silence -Wmissing-prototypes. */
void _initialize_frv_linux_tdep (void);
void
_initialize_frv_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_frv, 0, GDB_OSABI_LINUX, frv_linux_init_abi);
gdbarch_register_osabi_sniffer (bfd_arch_frv,
bfd_target_elf_flavour,
frv_linux_elf_osabi_sniffer);
}