gdbserver/ChangeLog:

	* linux-arm-low.c (arm_linux_hw_point_initialize): Distinguish
	between unsupported TYPE and unimplementable ADDR/LEN combination.
	(arm_insert_point): Act on new return value.

testsuite/ChangeLog:

	* gdb.base/watchpoint.exp (test_wide_location_1): Expect software
	watchpoints on ARM.  When expecting software watchpoints, tolerate
	(remote) targets that report unsupported hardware watchpoint only
	at continue time.
	(test_wide_location_2): Likewise.

4 files changed, 58 insertions, 15 deletions

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 4e40aa9..6a1259b 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,9 @@
+2012-08-01  Ulrich Weigand  <ulrich.weigand@linaro.org>
+
+	* linux-arm-low.c (arm_linux_hw_point_initialize): Distinguish
+	between unsupported TYPE and unimplementable ADDR/LEN combination.
+	(arm_insert_point): Act on new return value.
+
 2012-07-31  Pedro Alves  <palves@redhat.com>
 
 	* server.c (process_point_options): Only skip tokens if we find
diff --git a/gdb/gdbserver/linux-arm-low.c b/gdb/gdbserver/linux-arm-low.c
index 1037083..2718cec 100644
--- a/gdb/gdbserver/linux-arm-low.c
+++ b/gdb/gdbserver/linux-arm-low.c
@@ -432,8 +432,9 @@ arm_linux_hw_breakpoint_equal (const struct arm_linux_hw_breakpoint *p1,
 
 /* Initialize the hardware breakpoint structure P for a breakpoint or
    watchpoint at ADDR to LEN.  The type of watchpoint is given in TYPE.
-   Returns -1 if TYPE is unsupported, 0 if TYPE represents a breakpoint,
-   and 1 if type represents a watchpoint.  */
+   Returns -1 if TYPE is unsupported, or -2 if the particular combination
+   of ADDR and LEN cannot be implemented.  Otherwise, returns 0 if TYPE
+   represents a breakpoint and 1 if type represents a watchpoint.  */
 static int
 arm_linux_hw_point_initialize (char type, CORE_ADDR addr, int len,
 			       struct arm_linux_hw_breakpoint *p)
@@ -483,7 +484,7 @@ arm_linux_hw_point_initialize (char type, CORE_ADDR addr, int len,
 	  break;
 	default:
 	  /* Unsupported. */
-	  return -1;
+	  return -2;
 	}
     }
   else
@@ -493,17 +494,17 @@ arm_linux_hw_point_initialize (char type, CORE_ADDR addr, int len,
 
       /* Can not set watchpoints for zero or negative lengths.  */
       if (len <= 0)
-	return -1;
+	return -2;
       /* The current ptrace interface can only handle watchpoints that are a
 	 power of 2.  */
       if ((len & (len - 1)) != 0)
-	return -1;
+	return -2;
 
       /* Test that the range [ADDR, ADDR + LEN) fits into the largest address
 	 range covered by a watchpoint.  */
       aligned_addr = addr & ~(max_wp_length - 1);
       if (aligned_addr + max_wp_length < addr + len)
-	return -1;
+	return -2;
 
       mask = (1 << len) - 1;
     }
@@ -560,7 +561,7 @@ arm_insert_point (char type, CORE_ADDR addr, int len)
   if (watch < 0)
     {
       /* Unsupported.  */
-      return 1;
+      return watch == -1 ? 1 : -1;
     }
 
   if (watch)
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 1a4262c..b638681 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2012-08-01  Ulrich Weigand  <ulrich.weigand@linaro.org>
+
+	* gdb.base/watchpoint.exp (test_wide_location_1): Expect software
+	watchpoints on ARM.  When expecting software watchpoints, tolerate
+	(remote) targets that report unsupported hardware watchpoint only
+	at continue time.
+	(test_wide_location_2): Likewise.
+
 2012-08-01  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
 	* gdb.base/valgrind-infcall.exp: Relax the UNSUPPORTED check for more
diff --git a/gdb/testsuite/gdb.base/watchpoint.exp b/gdb/testsuite/gdb.base/watchpoint.exp
index 2941fbf..a461cb2 100644
--- a/gdb/testsuite/gdb.base/watchpoint.exp
+++ b/gdb/testsuite/gdb.base/watchpoint.exp
@@ -603,13 +603,15 @@ proc test_watch_location {} {
 
 proc test_wide_location_1 {} {
     global no_hw
+    global gdb_prompt
 
     # This test watches two words on most 32-bit ABIs, and one word on
     # most 64-bit ABIs.
 
     # Platforms where the target can't watch such a large region
     # should clear hw_expected below.
-    if { $no_hw || [target_info exists gdb,no_hardware_watchpoints] } {
+    if { $no_hw || [target_info exists gdb,no_hardware_watchpoints]
+         || [istarget arm*-*-*] } {
 	set hw_expected 0
     } else {
 	set hw_expected 1
@@ -625,9 +627,21 @@ proc test_wide_location_1 {} {
 	    "continue with watch foo2"
     } else {
 	gdb_test "watch foo2" "atchpoint .*: .*" "watch foo2"
-	gdb_test "continue" \
-	    "Continuing.*\[Ww\]atchpoint .*: .*New value = \\\{val = \\\{0, 11\\\}\\\}.*" \
-	    "continue with watch foo2"
+	set test "continue with watch foo2"
+	gdb_test_multiple "cont" $test {
+	    -re "Continuing.*\[Ww\]atchpoint .*: .*New value = \\\{val = \\\{0, 11\\\}\\\}.*$gdb_prompt $" {
+		pass $test
+	    }
+	    -re "Could not insert hardware breakpoints:.*You may have requested too many hardware breakpoints/watchpoints.*$gdb_prompt $" {
+		# This may happen with remote targets that support
+		# hardware watchpoints.  We only find out the
+		# watchpoint was too large, for example, at insert
+		# time.  If GDB is ever adjusted to downgrade the
+		# watchpoint automatically in this case, this match
+		# should be removed.
+		pass $test
+	    }
+	}
     }
 
     gdb_test_no_output "delete \$bpnum" "delete watch foo2"
@@ -635,13 +649,15 @@ proc test_wide_location_1 {} {
 
 proc test_wide_location_2 {} {
     global no_hw
+    global gdb_prompt
 
     # This test watches four words on most 32-bit ABIs, and two words
     # on 64-bit ABIs.
 
     # Platforms where the target can't watch such a large region
     # should clear hw_expected below.
-    if { $no_hw || [target_info exists gdb,no_hardware_watchpoints] } {
+    if { $no_hw || [target_info exists gdb,no_hardware_watchpoints]
+         || [istarget arm*-*-*] } {
 	set hw_expected 0
     } else {
 	set hw_expected 1
@@ -657,9 +673,21 @@ proc test_wide_location_2 {} {
 	    "continue with watch foo4"
     } else {
 	gdb_test "watch foo4" "atchpoint .*: .*" "watch foo4"
-	gdb_test "continue" \
-	    "Continuing.*\[Ww\]atchpoint .*: .*New value = \\\{val = \\\{0, 0, 0, 33\\\}\\\}.*" \
-	    "continue with watch foo4"
+	set test "continue with watch foo4"
+	gdb_test_multiple "cont" $test {
+	    -re "Continuing.*\[Ww\]atchpoint .*: .*New value = \\\{val = \\\{0, 0, 0, 33\\\}\\\}.*$gdb_prompt $" {
+		pass $test
+	    }
+	    -re "Could not insert hardware breakpoints:.*You may have requested too many hardware breakpoints/watchpoints.*$gdb_prompt $" {
+		# This may happen with remote targets that support
+		# hardware watchpoints.  We only find out the
+		# watchpoint was too large, for example, at insert
+		# time.  If GDB is ever adjusted to downgrade the
+		# watchpoint automatically in this case, this match
+		# should be removed.
+		pass $test
+	    }
+	}
     }
 
     gdb_test_no_output "delete \$bpnum" "delete watch foo4"