Detect 64-bit-ness in PowerPC Book III-E

This patch is to teach both GDB and GDBServer to detect 64-bit inferior
correctly.  We find a problem that GDBServer is unable to detect on a
e5500 core processor.  Current GDBServer assumes that MSR is a 64-bit
register, but MSR is a 32-bit register in Book III-E.  This patch is
to fix this problem by checking the right bit in MSR, in order to handle
both Book III-S and Book III-E.  In order to detect Book III-S and
Book III-E, we check the PPC_FEATURE_BOOKE from the host's HWCAP (by
getauxval on glibc >= 2.16.  If getauxval doesn't exist, we implement
the fallback by parsing /proc/self/auxv), because it should an invariant
on the same machine cross different processes.

In order to share code, I add nat/ppc-linux.c for both GDB and
GDBserver side.

gdb:

2015-01-14  Yao Qi  <yao@codesourcery.com>

	* Makefile.in (ppc-linux.o): New rule.
	* config/powerpc/ppc64-linux.mh (NATDEPFILES): Add ppc-linux.o.
	* configure.ac: AC_CHECK_FUNCS(getauxval).
	* config.in: Re-generated.
	* configure: Re-generated.
	* nat/ppc-linux.h [__powerpc64__] (ppc64_64bit_inferior_p):
	Declare.
	* nat/ppc-linux.c: New file.
	* ppc-linux-nat.c (ppc_linux_target_wordsize) [__powerpc64__]:
	Call ppc64_64bit_inferior_p.

gdb/gdbserver:

2015-01-14  Yao Qi  <yao@codesourcery.com>

	* Makefile.in (SFILES): Add nat/ppc-linux.c.
	(ppc-linux.o): New rule.
	* configure.srv (powerpc*-*-linux*): Add ppc-linux.o.
	* configure.ac: AC_CHECK_FUNCS(getauxval).
	* config.in: Re-generated.
	* configure: Re-generated.
	* linux-ppc-low.c (ppc_arch_setup) [__powerpc64__]: Call
	ppc64_64bit_inferior_p

7 files changed, 22 insertions, 7 deletions

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 2b844a0..f762daf 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,5 +1,16 @@
 2015-01-14  Yao Qi  <yao@codesourcery.com>
 
+	* Makefile.in (SFILES): Add nat/ppc-linux.c.
+	(ppc-linux.o): New rule.
+	* configure.srv (powerpc*-*-linux*): Add ppc-linux.o.
+	* configure.ac: AC_CHECK_FUNCS(getauxval).
+	* config.in: Re-generated.
+	* configure: Re-generated.
+	* linux-ppc-low.c (ppc_arch_setup) [__powerpc64__]: Call
+	ppc64_64bit_inferior_p
+
+2015-01-14  Yao Qi  <yao@codesourcery.com>
+
 	* linux-ppc-low.c: Include "nat/ppc-linux.h".
 	 (PPC_FEATURE_HAS_VSX): Move to nat/ppc-linux.h.
 	(PPC_FEATURE_HAS_ALTIVEC,  PPC_FEATURE_HAS_SPE): Likewise.
diff --git a/gdb/gdbserver/Makefile.in b/gdb/gdbserver/Makefile.in
index 1ed2ec8..0e442fc 100644
--- a/gdb/gdbserver/Makefile.in
+++ b/gdb/gdbserver/Makefile.in
@@ -155,7 +155,7 @@ SFILES=	$(srcdir)/gdbreplay.c $(srcdir)/inferiors.c $(srcdir)/dll.c \
 	$(srcdir)/linux-m32r-low.c \
 	$(srcdir)/linux-m68k-low.c $(srcdir)/linux-mips-low.c \
 	$(srcdir)/linux-nios2-low.c \
-	$(srcdir)/linux-ppc-low.c \
+	$(srcdir)/linux-ppc-low.c $(srcdir)/nat/ppc-linux.c \
 	$(srcdir)/linux-s390-low.c \
 	$(srcdir)/linux-sh-low.c $(srcdir)/linux-sparc-low.c \
 	$(srcdir)/linux-x86-low.c \
@@ -581,6 +581,9 @@ linux-waitpid.o: ../nat/linux-waitpid.c
 mips-linux-watch.o: ../nat/mips-linux-watch.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
+ppc-linux.o: ../nat/ppc-linux.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
 
 aarch64.c : $(srcdir)/../regformats/aarch64.dat $(regdat_sh)
 	$(SHELL) $(regdat_sh) $(srcdir)/../regformats/aarch64.dat aarch64.c
diff --git a/gdb/gdbserver/config.in b/gdb/gdbserver/config.in
index fd80adc..8f68ed2 100644
--- a/gdb/gdbserver/config.in
+++ b/gdb/gdbserver/config.in
@@ -60,6 +60,9 @@
 /* Define to 1 if you have the `fdwalk' function. */
 #undef HAVE_FDWALK
 
+/* Define to 1 if you have the `getauxval' function. */
+#undef HAVE_GETAUXVAL
+
 /* Define to 1 if you have the `getrlimit' function. */
 #undef HAVE_GETRLIMIT
 
diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index 45efc51..55bd2c5 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -4745,7 +4745,7 @@ fi
 
 done
 
-for ac_func in pread pwrite pread64
+for ac_func in getauxval pread pwrite pread64
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index 02082cc..39e3a06 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -90,7 +90,7 @@ AC_CHECK_HEADERS(sgtty.h termio.h termios.h sys/reg.h string.h dnl
 		 fcntl.h signal.h sys/file.h dnl
 		 sys/ioctl.h netinet/in.h sys/socket.h netdb.h dnl
 		 netinet/tcp.h arpa/inet.h)
-AC_CHECK_FUNCS(pread pwrite pread64)
+AC_CHECK_FUNCS(getauxval pread pwrite pread64)
 
 GDB_AC_COMMON
 
diff --git a/gdb/gdbserver/configure.srv b/gdb/gdbserver/configure.srv
index 679fc9f..f52aee2 100644
--- a/gdb/gdbserver/configure.srv
+++ b/gdb/gdbserver/configure.srv
@@ -217,7 +217,7 @@ case "${target}" in
 			srv_regobj="${srv_regobj} powerpc-isa205-64l.o"
 			srv_regobj="${srv_regobj} powerpc-isa205-altivec64l.o"
 			srv_regobj="${srv_regobj} powerpc-isa205-vsx64l.o"
-			srv_tgtobj="$srv_linux_obj linux-ppc-low.o"
+			srv_tgtobj="$srv_linux_obj linux-ppc-low.o ppc-linux.o"
 			srv_xmlfiles="rs6000/powerpc-32l.xml"
 			srv_xmlfiles="${srv_xmlfiles} rs6000/powerpc-altivec32l.xml"
 			srv_xmlfiles="${srv_xmlfiles} rs6000/powerpc-cell32l.xml"
diff --git a/gdb/gdbserver/linux-ppc-low.c b/gdb/gdbserver/linux-ppc-low.c
index 6e880c1..188fac0 100644
--- a/gdb/gdbserver/linux-ppc-low.c
+++ b/gdb/gdbserver/linux-ppc-low.c
@@ -398,13 +398,11 @@ ppc_arch_setup (void)
   current_process ()->tdesc = tdesc;
   ppc_hwcap = 0;
 
-  /* Only if the high bit of the MSR is set, we actually have
-     a 64-bit inferior.  */
   regcache = new_register_cache (tdesc);
   fetch_inferior_registers (regcache, find_regno (tdesc, "msr"));
   collect_register_by_name (regcache, "msr", &msr);
   free_register_cache (regcache);
-  if (msr < 0)
+  if (ppc64_64bit_inferior_p (msr))
     {
       ppc_get_hwcap (&ppc_hwcap);
       if (ppc_hwcap & PPC_FEATURE_CELL)