binutils-gdb/gdb/mips-nat.c

255 lines
7.3 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* Low level DECstation interface to ptrace, for GDB when running native.
Copyright 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1999, 2000, 2001
Free Software Foundation, Inc.
Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
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 "inferior.h"
#include "gdbcore.h"
#include "regcache.h"
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/user.h>
#undef JB_S0
#undef JB_S1
#undef JB_S2
#undef JB_S3
#undef JB_S4
#undef JB_S5
#undef JB_S6
#undef JB_S7
#undef JB_SP
#undef JB_S8
#undef JB_PC
#undef JB_SR
#undef NJBREGS
#include <setjmp.h> /* For JB_XXX. */
/* Size of elements in jmpbuf */
#define JB_ELEMENT_SIZE 4
/* Map gdb internal register number to ptrace ``address''.
These ``addresses'' are defined in DECstation <sys/ptrace.h> */
static int
register_ptrace_addr (int regno)
{
return (regno < 32 ? GPR_BASE + regno
: regno == mips_regnum (current_gdbarch)->pc ? PC
: regno == mips_regnum (current_gdbarch)->cause ? CAUSE
: regno == mips_regnum (current_gdbarch)->hi ? MMHI
: regno == mips_regnum (current_gdbarch)->lo ? MMLO
: regno == mips_regnum (current_gdbarch)->fp_control_status ? FPC_CSR
: regno == mips_regnum (current_gdbarch)->fp_implementation_revision ? FPC_EIR
: regno >= FP0_REGNUM ? FPR_BASE + (regno - FP0_REGNUM)
: 0);
}
static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);
/* Get all registers from the inferior */
void
fetch_inferior_registers (int regno)
{
unsigned int regaddr;
char buf[MAX_REGISTER_SIZE];
int i;
char zerobuf[MAX_REGISTER_SIZE];
memset (zerobuf, 0, MAX_REGISTER_SIZE);
deprecated_registers_fetched ();
for (regno = 1; regno < NUM_REGS; regno++)
{
regaddr = register_ptrace_addr (regno);
for (i = 0; i < DEPRECATED_REGISTER_RAW_SIZE (regno); i += sizeof (int))
{
*(int *) &buf[i] = ptrace (PT_READ_U, PIDGET (inferior_ptid),
(PTRACE_ARG3_TYPE) regaddr, 0);
regaddr += sizeof (int);
}
supply_register (regno, buf);
}
supply_register (ZERO_REGNUM, zerobuf);
/* Frame ptr reg must appear to be 0; it is faked by stack handling code. */
supply_register (DEPRECATED_FP_REGNUM, zerobuf);
}
/* Store our register values back into the inferior.
If REGNO is -1, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
void
store_inferior_registers (int regno)
{
unsigned int regaddr;
char buf[80];
if (regno > 0)
{
if (regno == ZERO_REGNUM || regno == PS_REGNUM
|| regno == mips_regnum (current_gdbarch)->badvaddr
|| regno == mips_regnum (current_gdbarch)->cause
|| regno == mips_regnum (current_gdbarch)->fp_implementation_revision
|| regno == DEPRECATED_FP_REGNUM
|| (regno >= FIRST_EMBED_REGNUM && regno <= LAST_EMBED_REGNUM))
return;
regaddr = register_ptrace_addr (regno);
errno = 0;
ptrace (PT_WRITE_U, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) regaddr,
read_register (regno));
if (errno != 0)
{
sprintf (buf, "writing register number %d", regno);
perror_with_name (buf);
}
}
else
{
for (regno = 0; regno < NUM_REGS; regno++)
store_inferior_registers (regno);
}
}
/* Figure out where the longjmp will land.
We expect the first arg to be a pointer to the jmp_buf structure from which
we extract the pc (JB_PC) that we will land at. The pc is copied into PC.
This routine returns true on success. */
int
get_longjmp_target (CORE_ADDR *pc)
{
CORE_ADDR jb_addr;
char *buf;
buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
jb_addr = read_register (A0_REGNUM);
if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
TARGET_PTR_BIT / TARGET_CHAR_BIT))
return 0;
*pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
return 1;
}
/* Extract the register values out of the core file and store
them where `read_register' will find them.
CORE_REG_SECT points to the register values themselves, read into memory.
CORE_REG_SIZE is the size of that area.
WHICH says which set of registers we are handling (0 = int, 2 = float
on machines where they are discontiguous).
REG_ADDR is the offset from u.u_ar0 to the register values relative to
core_reg_sect. This is used with old-fashioned core files to
locate the registers in a large upage-plus-stack ".reg" section.
Original upage address X is at location core_reg_sect+x+reg_addr.
*/
static void
fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
CORE_ADDR reg_addr)
{
int regno;
unsigned int addr;
int bad_reg = -1;
reg_ptr = -reg_addr; /* Original u.u_ar0 is -reg_addr. */
char zerobuf[MAX_REGISTER_SIZE];
memset (zerobuf, 0, MAX_REGISTER_SIZE);
/* If u.u_ar0 was an absolute address in the core file, relativize it now,
so we can use it as an offset into core_reg_sect. When we're done,
"register 0" will be at core_reg_sect+reg_ptr, and we can use
register_addr to offset to the other registers. If this is a modern
core file without a upage, reg_ptr will be zero and this is all a big
NOP. */
if (reg_ptr > core_reg_size)
#ifdef KERNEL_U_ADDR
reg_ptr -= KERNEL_U_ADDR;
#else
error ("Old mips core file can't be processed on this machine.");
#endif
for (regno = 0; regno < NUM_REGS; regno++)
{
addr = register_addr (regno, reg_ptr);
if (addr >= core_reg_size)
{
if (bad_reg < 0)
bad_reg = regno;
}
else
{
supply_register (regno, core_reg_sect + addr);
}
}
if (bad_reg >= 0)
{
error ("Register %s not found in core file.", REGISTER_NAME (bad_reg));
}
supply_register (ZERO_REGNUM, zerobuf);
/* Frame ptr reg must appear to be 0; it is faked by stack handling code. */
supply_register (DEPRECATED_FP_REGNUM, zerobuf);
}
/* Return the address in the core dump or inferior of register REGNO.
BLOCKEND is the address of the end of the user structure. */
CORE_ADDR
register_addr (int regno, CORE_ADDR blockend)
{
CORE_ADDR addr;
if (regno < 0 || regno >= NUM_REGS)
error ("Invalid register number %d.", regno);
REGISTER_U_ADDR (addr, blockend, regno);
return addr;
}
/* Register that we are able to handle mips core file formats.
FIXME: is this really bfd_target_unknown_flavour? */
static struct core_fns mips_core_fns =
{
bfd_target_unknown_flavour, /* core_flavour */
default_check_format, /* check_format */
default_core_sniffer, /* core_sniffer */
fetch_core_registers, /* core_read_registers */
NULL /* next */
};
void
_initialize_core_mips (void)
{
add_core_fns (&mips_core_fns);
}