* breakpoint.h (enum bptype): Add bp_hardware_watchpoint and

	bp_watchpoint_scope breakpoints.
	(struct breakpoint): Add val_chain and related_breakpoint fields
	for use by watchpoints.

	* breakpoint.c (within_scope): Delete.  No longer used.
	(TARGET_CAN_USE_HARDWARE_WATCHPOINT): Provide default definition.
	(target_{remove,insert}_watchpoint): Likewise.
	(can_use_hardware_watchpoint): New function.
	(remove_breakpoint): New function to remove a single breakpoint
	or hardware watchpoint.
	(insert_breakpoints): Handle insertion of hardware watchpoints.
	Store a copy of the value chain derived from the watchpoint
	expression.
	(remove_breakpoints): Simplify by using remove_breakpoint.
	(delete_breakpoint): Likewise.
	(watchpoint_check): Delete the watchpoint and watchpoint scope
	breakpoints when the watchpoint goes out of scope.  Save & restore
	the current frame after checking watchpoints.
	(breakpoint_init_inferior): Likewise (restarting the program
	makes all local watchpoints go out of scope).
	(bpstat_stop_status): Handle hardware watchpoints much like normal
	watchpoints. Delete the watchpoint and watchpoint scope breakpoint
	when the watchpoint goes out of scope.  Remove and reinsert all
	breakpoints before returning if we stopped when a hardware watchpoint
	fired.
	(watch_command): Use a hardware watchpoint when possible.  If
	watching a local expression, build a scope breakpoint too.
	(map_breakpoint_numbers): Also call given function for any
	related breakpoints.
	(disable_breakpoint): Never disable a scope breakpoint.
	(enable_breakpoint): Handle hardware breakpoints much like normal
	breakpoints, but recompute the watchpoint_scope breakpoint's
	frame and address  (if we have an associated scope breakpoint).
	(read_memory_nobpt): Handle hardware watchpoints like normal
	watchpoints.  When necessary handle watchpoint_scope breakpoints.
	(print_it_normal, bpstat_what, breakpoint_1, mention): Likewise.
	(clear_command, breakpoint_re_set_one, enable_command): Likewise.
	(disable_command): Likewise.

	* blockframe.c (find_frame_addr_in_frame_chain): New function.
	Extern prototype added to frame.h

	* infrun.c (wait_for_inferior): Set current_frame and select
	a frame before checking if we stopped due to a hardare watchpoint
	firing.  Handle stepping over hardware watchpoints.
	(normal_stop): Remove unnecessary call to select_frame.

	* value.h (value_release_to_mark): Declare.
	* values.c (value_release_to_mark): New function.

	* procfs.c (procfs_wait): Add cases for hardware watchpoints.
	(procfs_set_watchpoint, procfs_stopped_by_watchpoint): New functions.

	* hppab-nat.c (hppa_set_watchpoint): New function.

	* config/pa/nm-hppab.h (STOPPED_BY_WATCHPOINT): Define.
	(HAVE_STEPPABLE_WATCHPOINT): Define.
	(TARGET_CAN_USE_HARDWARE_WATCHPOINT): Define.
	(target_{insert,delete}_watchpoint): Define.

1 files changed, 59 insertions, 0 deletions

diff --git a/gdb/hppab-nat.c b/gdb/hppab-nat.c
index 990c952..5bc0bb4 100644
--- a/gdb/hppab-nat.c
+++ b/gdb/hppab-nat.c
@@ -140,3 +140,62 @@ store_inferior_registers (regno)
   return;
 }
 
+
+/* PT_PROT is specific to the PA BSD kernel and isn't documented
+   anywhere (except here).  
+
+   PT_PROT allows one to enable/disable the data memory break bit
+   for pages of memory in an inferior process.  This bit is used
+   to cause "Data memory break traps" to occur when the appropriate
+   page is written to.
+
+   The arguments are as follows:
+
+      PT_PROT -- The ptrace action to perform.
+
+      INFERIOR_PID -- The pid of the process who's page table entries
+      will be modified.
+
+      PT_ARGS -- The *address* of a 3 word block of memory which has
+      additional information:
+
+        word 0 -- The start address to watch.  This should be a page-aligned
+	address.
+
+	word 1 -- The ending address to watch.  Again, this should be a 
+	page aligned address.
+
+	word 2 -- Nonzero to enable the data memory break bit on the
+	given address range or zero to disable the data memory break
+	bit on the given address range.
+
+  This call may fail if the given addresses are not valid in the inferior
+  process.  This most often happens when restarting a program which
+  as watchpoints inserted on heap or stack memory.  */
+	
+#define PT_PROT 21
+
+int
+hppa_set_watchpoint (addr, len, flag)
+     int addr, len, flag;
+{
+  int pt_args[3];
+  pt_args[0] = addr;
+  pt_args[1] = addr + len;
+  pt_args[2] = flag;
+
+  /* Mask off the lower 12 bits since we want to work on a page basis.  */
+  pt_args[0] >>= 12; 
+  pt_args[1] >>= 12; 
+
+  /* Rounding adjustments.  */
+  pt_args[1] -= pt_args[0]; 
+  pt_args[1]++; 
+
+  /* Put the lower 12 bits back as zero.  */
+  pt_args[0] <<= 12; 
+  pt_args[1] <<= 12; 
+
+  /* Do it.  */
+  return ptrace (PT_PROT, inferior_pid, (PTRACE_ARG3_TYPE) pt_args, 0);
+}