4.4BSD/usr/src/contrib/gdb-4.7.lbl/gdb/mips-nat.c
/* Low level DECstation interface to ptrace, for GDB when running native.
Copyright 1988, 1989, 1991, 1992 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
#include "inferior.h"
#include "gdbcore.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> */
#define REGISTER_PTRACE_ADDR(regno) \
(regno < 32 ? GPR_BASE + regno \
: regno == PC_REGNUM ? PC \
: regno == CAUSE_REGNUM ? CAUSE \
: regno == HI_REGNUM ? MMHI \
: regno == LO_REGNUM ? MMLO \
: regno == FCRCS_REGNUM ? FPC_CSR \
: regno == FCRIR_REGNUM ? FPC_EIR \
: regno >= FP0_REGNUM ? FPR_BASE + (regno - FP0_REGNUM) \
: 0)
static char zerobuf[MAX_REGISTER_RAW_SIZE] = {0};
/* Get all registers from the inferior */
void
fetch_inferior_registers (regno)
int regno;
{
register unsigned int regaddr;
char buf[MAX_REGISTER_RAW_SIZE];
register int i;
registers_fetched ();
for (regno = 1; regno < NUM_REGS; regno++)
{
regaddr = REGISTER_PTRACE_ADDR (regno);
for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
{
*(int *) &buf[i] = ptrace (PT_READ_U, inferior_pid,
(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 (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 (regno)
int regno;
{
register unsigned int regaddr;
char buf[80];
if (regno == 0)
return;
if (regno > 0)
{
regaddr = REGISTER_PTRACE_ADDR (regno);
errno = 0;
ptrace (PT_WRITE_U, inferior_pid, (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++)
{
if (regno == ZERO_REGNUM || regno == PS_REGNUM
|| regno == BADVADDR_REGNUM || regno == CAUSE_REGNUM
|| regno == FCRIR_REGNUM || regno == FP_REGNUM
|| (regno >= FIRST_EMBED_REGNUM && regno <= LAST_EMBED_REGNUM))
continue;
regaddr = register_addr (regno, 1);
errno = 0;
ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
read_register (regno));
if (errno != 0)
{
sprintf (buf, "writing all regs, number %d", regno);
perror_with_name (buf);
}
}
}
}
/* 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(pc)
CORE_ADDR *pc;
{
CORE_ADDR jb_addr;
jb_addr = read_register(A0_REGNUM);
if (target_read_memory(jb_addr + JB_PC * JB_ELEMENT_SIZE, pc,
sizeof(CORE_ADDR)))
return 0;
SWAP_TARGET_AND_HOST(pc, sizeof(CORE_ADDR));
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.
*/
void
fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
char *core_reg_sect;
unsigned core_reg_size;
int which;
unsigned reg_addr;
{
register int regno;
register unsigned int addr;
int bad_reg = -1;
register reg_ptr = -reg_addr; /* Original u.u_ar0 is -reg_addr. */
/* 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)
reg_ptr -= KERNEL_U_ADDR;
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.", reg_names[bad_reg]);
}
supply_register (ZERO_REGNUM, zerobuf);
/* Frame ptr reg must appear to be 0; it is faked by stack handling code. */
supply_register (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. */
unsigned int
register_addr (regno, blockend)
int regno;
int blockend;
{
int addr;
if (regno < 0 || regno >= NUM_REGS)
error ("Invalid register number %d.", regno);
REGISTER_U_ADDR (addr, blockend, regno);
return addr;
}