binutils-gdb/gdb/nat/ppc-linux.c
Pedro Franco de Carvalho 2e077f5e67 [PowerPC] Consolidate wordsize getter between native and gdbserver
This patch moves the native target wordsize getter for ppc linux to
nat/ so that it can be used to simplify ppc_arch_setup in
gdbserver. The ptrace call used to get MSR for this is ultimately the
same as before, but it is no longer necessary to create a temporary
regcache to call fetch_inferior_registers.

gdb/ChangeLog:
2018-05-22  Pedro Franco de Carvalho  <pedromfc@linux.vnet.ibm.com>

	* configure.nat <linux powerpc>: Add ppc-linux.o to NATDEPFILES.
	* ppc-linux-nat.c (ppc_linux_target_wordsize): Move to
	nat/ppc-linux.c.
	(ppc_linux_nat_target::auxv_parse): Get thread id tid. Call
	ppc_linux_target_wordsize with tid.
	(ppc_linux_nat_target::read_description): Call ppc_linux_target
	wordsize with tid.
	* nat/ppc-linux.c: Include nat/gdb_ptrace.h.
	(ppc64_64bit_inferior_p): Add static and inline specifiers.
	(ppc_linux_target_wordsize): Move here from ppc-linux-nat.c. Add
	tid parameter. Remove static specifier.
	* nat/ppc-linux.h (ppc64_64bit_inferior_p): Remove declaration.
	(ppc_linux_target_wordsize): New declaration.

gdb/gdbserver/ChangeLog:
2018-05-22  Pedro Franco de Carvalho  <pedromfc@linux.vnet.ibm.com>

	* linux-ppc-low.c (ppc_arch_setup): Remove code for getting the
	wordsize of the inferior. Call ppc_linux_target_wordsize.
2018-05-22 11:52:02 -03:00

96 lines
2.4 KiB
C

/*Copyright (C) 2015-2018 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 3 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, see <http://www.gnu.org/licenses/>. */
#include "common-defs.h"
#include "ppc-linux.h"
#include "nat/gdb_ptrace.h"
#include <elf.h>
#ifdef HAVE_GETAUXVAL
#include <sys/auxv.h>
#endif
#ifdef __powerpc64__
/* Get the HWCAP from the process of GDB or GDBserver. If success,
save it in *VALP. */
static void
ppc64_host_hwcap (unsigned long *valp)
{
#ifdef HAVE_GETAUXVAL
*valp = getauxval (AT_HWCAP);
#else
unsigned long data[2];
FILE *f = fopen ("/proc/self/auxv", "r");
if (f == NULL)
return;
while (fread (data, sizeof (data), 1, f) > 0)
{
if (data[0] == AT_HWCAP)
{
*valp = data[1];
break;
}
}
fclose (f);
#endif /* HAVE_GETAUXVAL */
}
static inline int
ppc64_64bit_inferior_p (long msr)
{
unsigned long ppc_host_hwcap = 0;
/* Get host's HWCAP to check whether the machine is Book E. */
ppc64_host_hwcap (&ppc_host_hwcap);
/* We actually have a 64-bit inferior only if the certain bit of the
MSR is set. The PowerISA Book III-S MSR is different from the
PowerISA Book III-E MSR. The Book III-S MSR is 64 bits wide, and
its MSR[SF] is the bit 0 of a 64-bit value. Book III-E MSR is 32
bits wide, and its MSR[CM] is the bit 0 of a 32-bit value. */
if (ppc_host_hwcap & PPC_FEATURE_BOOKE)
return msr & 0x80000000;
else
return msr < 0;
}
#endif
int
ppc_linux_target_wordsize (int tid)
{
int wordsize = 4;
/* Check for 64-bit inferior process. This is the case when the host is
64-bit, and in addition the top bit of the MSR register is set. */
#ifdef __powerpc64__
long msr;
errno = 0;
msr = (long) ptrace (PTRACE_PEEKUSER, tid, PT_MSR * 8, 0);
if (errno == 0 && ppc64_64bit_inferior_p (msr))
wordsize = 8;
#endif
return wordsize;
}