[RFC-v2] ARI fixes: Remove NAT_FILE for solaris

["Pierre Muller" <pierre dot muller at ics-cnrs dot unistra dot fr>]

  Thanks to Peter's answer to gdb  mailing list,
http://sourceware.org/ml/gdb/2010-04/msg00082.html
I was able to write a new patch.

  The main idea is to add a to_cannot_step_hw_watchpoints
filed to target_ops, create a macro called
target_cannot_step_hw_watchpoints and you that
inside infrun.c instead of the CANNOT_STEP_HW_WATCHPOINTS macro.

  The macro still gets defined for solaris 2.6 and 2.7 versions
and triggers solaris_cannot_step_hw_watchpoints
to return 1 instead of zero.

  The reason for using a function rather than an integer
field was to be able later (once Solaris has a gdbserver)
to also set this for remote targets.

Comments?

Pierre


2010-04-23  Pierre Muller  <muller@ics.u-strasbg.fr>

	* configure.ac (Solaris): Set CANNOT_STEP_HW_WATCHPOINTS macro
	for i386 cpu family and OS version <= 2.7.
	* config.in: Regenerate.
	* configure: Idem.
	* i386-sol2-nat.c (solaris_cannot_step_hw_watchpoints): New
function.
	(_initialize_amd64_sol2_nat): Set target
to_cannot_step_hw_watchpoints
	to solaris_cannot_step_hw_watchpoints.
	* infrun.c (show_debug_infrun): Remove redefinition of
	CANNOT_STEP_HW_WATCHPOINTS macro.
	(resume): Replace CANNOT_STEP_HW_WATCHPOINTS macro with
	target_cannot_step_hw_watchpoints macro.
	* target.h (target_ops): Add to_cannot_step_hw_watchpoints
	field.
	(target_cannot_step_hw_watchpoints): New macro.
	* target.c (update_current_target): Inherited
	to_cannot_step_hw_watchpoints. 
	Set default to return_zero function.
	* config/i386/nm-i386sol2.h: Delete.
	* config/i386/i386sol2.mh: Remove NAT_FILE.
	* config/i386/sol2-64.mh: Idem.

Index: src/gdb/config.in
===================================================================
RCS file: /cvs/src/src/gdb/config.in,v
retrieving revision 1.116
diff -u -p -r1.116 config.in
--- src/gdb/config.in	10 Mar 2010 18:37:22 -0000	1.116
+++ src/gdb/config.in	22 Apr 2010 23:08:24 -0000
@@ -18,6 +18,9 @@
 /* Define to the number of bits in type 'wint_t'. */
 #undef BITSIZEOF_WINT_T
 
+/* Define for Solaris Kernel bug. */
+#undef CANNOT_STEP_HW_WATCHPOINTS
+
 /* Define to 1 if the compiler supports long long. */
 #undef CC_HAS_LONG_LONG
 
Index: src/gdb/configure
===================================================================
RCS file: /cvs/src/src/gdb/configure,v
retrieving revision 1.301
diff -u -p -r1.301 configure
--- src/gdb/configure	15 Mar 2010 17:03:01 -0000	1.301
+++ src/gdb/configure	22 Apr 2010 23:08:29 -0000
@@ -11882,6 +11882,15 @@ $as_echo "#define NEW_PROC_API 1" >>conf
 
 $as_echo "#define NEW_PROC_API 1" >>confdefs.h
 
+# This bug might have been solved, but for which version of solaris system?
+      if test "${gdb_host_cpu}" = "i386"; then
+	case "${host}" in
+	*-*-solaris2.[67] )
+
+$as_echo "#define CANNOT_STEP_HW_WATCHPOINTS 1" >>confdefs.h
+
+	esac
+      fi
       ;;
   mips-sgi-irix5*)
       # Work around <sys/proc.h> needing _KMEMUSER problem on IRIX 5.
Index: src/gdb/configure.ac
===================================================================
RCS file: /cvs/src/src/gdb/configure.ac,v
retrieving revision 1.116
diff -u -p -r1.116 configure.ac
--- src/gdb/configure.ac	15 Mar 2010 17:03:00 -0000	1.116
+++ src/gdb/configure.ac	22 Apr 2010 23:08:30 -0000
@@ -1035,6 +1035,14 @@ if test "${target}" = "${host}"; then
       AC_DEFINE(NEW_PROC_API, 1,
       [Define if you want to use new multi-fd /proc interface
        (replaces HAVE_MULTIPLE_PROC_FDS as well as other macros).])
+# This bug might have been solved, but for which version of solaris system?
+      if test "${gdb_host_cpu}" = "i386"; then
+	case "${host}" in
+	*-*-solaris2.[[67]] )
+	  AC_DEFINE(CANNOT_STEP_HW_WATCHPOINTS, 1,
+	  [Define for Solaris Kernel bug.])
+	esac
+      fi
       ;;
   mips-sgi-irix5*)
       # Work around <sys/proc.h> needing _KMEMUSER problem on IRIX 5.
Index: src/gdb/i386-sol2-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/i386-sol2-nat.c,v
retrieving revision 1.11
diff -u -p -r1.11 i386-sol2-nat.c
--- src/gdb/i386-sol2-nat.c	1 Jan 2010 07:31:34 -0000	1.11
+++ src/gdb/i386-sol2-nat.c	22 Apr 2010 23:08:30 -0000
@@ -130,6 +130,16 @@ fill_fpregset (const struct regcache *re
 
 #endif
 
+static int
+solaris_cannot_step_hw_watchpoints (void)
+{
+#ifdef CANNOT_STEP_HW_WATCHPOINTS
+  return 1;
+#else
+  return 0;
+#endif
+}
+
 /* Provide a prototype to silence -Wmissing-prototypes.  */
 extern void _initialize_amd64_sol2_nat (void);
 
@@ -145,6 +155,8 @@ _initialize_amd64_sol2_nat (void)
   procfs_use_watchpoints (t);
 #endif
 
+  t->to_cannot_step_hw_watchpoints = solaris_cannot_step_hw_watchpoints;
+
 #if defined (PR_MODEL_NATIVE) && (PR_MODEL_NATIVE == PR_MODEL_LP64)
   amd64_native_gregset32_reg_offset = amd64_sol2_gregset32_reg_offset;
   amd64_native_gregset32_num_regs =
Index: src/gdb/infrun.c
===================================================================
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.435
diff -u -p -r1.435 infrun.c
--- src/gdb/infrun.c	25 Mar 2010 20:48:53 -0000	1.435
+++ src/gdb/infrun.c	22 Apr 2010 23:08:32 -0000
@@ -179,16 +179,6 @@ show_debug_infrun (struct ui_file *file,
 #endif
 
 
-/* Convert the #defines into values.  This is temporary until wfi control
-   flow is completely sorted out.  */
-
-#ifndef CANNOT_STEP_HW_WATCHPOINTS
-#define CANNOT_STEP_HW_WATCHPOINTS 0
-#else
-#undef  CANNOT_STEP_HW_WATCHPOINTS
-#define CANNOT_STEP_HW_WATCHPOINTS 1
-#endif
-
 /* Tables of how to react to signals; the user sets them.  */
 
 static unsigned char *signal_stop;
@@ -1492,7 +1482,7 @@ resume (int step, enum target_signal sig
      Work around the problem by removing hardware watchpoints if a step is
      requested, GDB will check for a hardware watchpoint trigger after the
      step anyway.  */
-  if (CANNOT_STEP_HW_WATCHPOINTS && step)
+  if (target_cannot_step_hw_watchpoints () && step)
     remove_hw_watchpoints ();
 
 
Index: src/gdb/target.c
===================================================================
RCS file: /cvs/src/src/gdb/target.c,v
retrieving revision 1.247
diff -u -p -r1.247 target.c
--- src/gdb/target.c	19 Apr 2010 22:06:17 -0000	1.247
+++ src/gdb/target.c	22 Apr 2010 23:08:33 -0000
@@ -661,6 +661,7 @@ update_current_target (void)
       INHERIT (to_set_disconnected_tracing, t);
       INHERIT (to_set_circular_trace_buffer, t);
       INHERIT (to_get_tib_address, t);
+      INHERIT (to_cannot_step_hw_watchpoints, t);
       INHERIT (to_magic, t);
       /* Do not inherit to_memory_map.  */
       /* Do not inherit to_flash_erase.  */
@@ -857,6 +858,9 @@ update_current_target (void)
   de_fault (to_get_tib_address,
 	    (int (*) (ptid_t, CORE_ADDR *))
 	    tcomplain);
+  de_fault (to_cannot_step_hw_watchpoints,
+	    (int (*) (void))
+	    return_zero);
 #undef de_fault
 
   /* Finally, position the target-stack beneath the squashed
Index: src/gdb/target.h
===================================================================
RCS file: /cvs/src/src/gdb/target.h,v
retrieving revision 1.178
diff -u -p -r1.178 target.h
--- src/gdb/target.h	16 Apr 2010 07:49:35 -0000	1.178
+++ src/gdb/target.h	22 Apr 2010 23:08:35 -0000
@@ -686,6 +686,9 @@ struct target_ops
        a Windows OS specific feature.  */
     int (*to_get_tib_address) (ptid_t ptid, CORE_ADDR *addr);
 
+    /* Returns 1 if target needs to disable watchpoints before stepping.
*/
+    int (*to_cannot_step_hw_watchpoints) (void);
+
     int to_magic;
     /* Need sub-structure for target machine related rather than comm
related?
      */
@@ -1378,6 +1381,9 @@ extern int target_search_memory (CORE_AD
 #define target_get_tib_address(ptid, addr) \
   (*current_target.to_get_tib_address) ((ptid), (addr))
 
+#define target_cannot_step_hw_watchpoints() \
+  (*current_target.to_cannot_step_hw_watchpoints) ()
+
 /* Command logging facility.  */
 
 #define target_log_command(p)						\
Index: src/gdb/config/i386/i386sol2.mh
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/i386sol2.mh,v
retrieving revision 1.12
diff -u -p -r1.12 i386sol2.mh
--- src/gdb/config/i386/i386sol2.mh	26 Oct 2009 18:28:13 -0000	1.12
+++ src/gdb/config/i386/i386sol2.mh	22 Apr 2010 23:08:36 -0000
@@ -1,4 +1,3 @@
 # Host: Solaris x86
 NATDEPFILES= fork-child.o i386v4-nat.o i386-sol2-nat.o \
 	procfs.o proc-api.o proc-events.o proc-flags.o proc-why.o
-NAT_FILE= nm-i386sol2.h
Index: src/gdb/config/i386/nm-i386sol2.h
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/nm-i386sol2.h,v
retrieving revision 1.19
diff -u -p -r1.19 nm-i386sol2.h
--- src/gdb/config/i386/nm-i386sol2.h	1 Jan 2010 07:31:48 -0000	1.19
+++ src/gdb/config/i386/nm-i386sol2.h	22 Apr 2010 23:08:36 -0000
@@ -1,32 +0,0 @@
-/* Native support for i386 running Solaris 2.
-   Copyright 1998, 1999, 2000, 2007, 2008, 2009, 2010
-   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/>.
*/
-
-#ifdef NEW_PROC_API	/* Solaris 6 and above can do HW watchpoints */
-
-/* Solaris x86 2.6 and 2.7 targets have a kernel bug when stepping
-   over an instruction that causes a page fault without triggering
-   a hardware watchpoint. The kernel properly notices that it shouldn't
-   stop, because the hardware watchpoint is not triggered, but it forgets
-   the step request and continues the program normally.
-   Work around the problem by removing hardware watchpoints if a step is
-   requested, GDB will check for a hardware watchpoint trigger after the
-   step anyway.  */
-#define CANNOT_STEP_HW_WATCHPOINTS
-
-#endif /* NEW_PROC_API */
Index: src/gdb/config/i386/sol2-64.mh
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/sol2-64.mh,v
retrieving revision 1.2
diff -u -p -r1.2 sol2-64.mh
--- src/gdb/config/i386/sol2-64.mh	26 Oct 2009 18:28:13 -0000	1.2
+++ src/gdb/config/i386/sol2-64.mh	22 Apr 2010 23:08:36 -0000
@@ -1,4 +1,3 @@
 # Host: Solaris x86_64
 NATDEPFILES= fork-child.o amd64-nat.o i386v4-nat.o i386-sol2-nat.o \
 	procfs.o proc-api.o proc-events.o proc-flags.o proc-why.o
-NAT_FILE= nm-i386sol2.h