[PATCH 1/3] [GDBserver][Aarch64] Make watchpoint support use target_hw_bp_type.

[Pedro Alves <palves at redhat dot com>]

This makes linux-aarch64-low.c use target_hw_bp_type, like gdb's
aarch64-linux-nat.c.  The original motivation is decoupling
insert_point/remove_point from Z packet numbers, but I think making
the files a little bit more similar is a good thing on its own right.
Ideally we'd merge these files even...  The
aarch64_point_encode_ctrl_reg change is taken straight from GDB's
copy.

I confirmed with a cross compiler that this builds, but it's otherwise
untested.

gdb/gdbserver/
2014-04-23  Pedro Alves  <palves@redhat.com>

	* linux-aarch64-low.c: Include break-common.h.
	(enum target_point_type): Delete.
	(Z_packet_to_point_type): Rename to ...
	(Z_packet_to_target_hw_bp_type): ... this, and return a
	target_hw_bp_type instead.
	(aarch64_show_debug_reg_state): Take an enum target_hw_bp_type
	instead of an enum target_point_type.
	(aarch64_point_encode_ctrl_reg): Likewise.  Compute type mask from
	breakpoint type.
	(aarch64_dr_state_insert_one_point)
	(aarch64_dr_state_remove_one_point, aarch64_handle_breakpoint)
	(aarch64_handle_aligned_watchpoint)
	(aarch64_handle_unaligned_watchpoint, aarch64_handle_watchpoint):
	Take an enum target_hw_bp_type instead of an enum
	target_point_type.
	(aarch64_supports_z_point_type): New function.
	(aarch64_insert_point, aarch64_remove_point): Use it.  Adjust to
	use Z_packet_to_target_hw_bp_type.
---
 gdb/gdbserver/linux-aarch64-low.c | 100 +++++++++++++++++++++++---------------
 1 file changed, 61 insertions(+), 39 deletions(-)

diff --git a/gdb/gdbserver/linux-aarch64-low.c b/gdb/gdbserver/linux-aarch64-low.c
index 627ade3..8b32d79 100644
--- a/gdb/gdbserver/linux-aarch64-low.c
+++ b/gdb/gdbserver/linux-aarch64-low.c
@@ -29,6 +29,7 @@
 #include <sys/uio.h>
 
 #include "gdb_proc_service.h"
+#include "break-common.h"
 
 /* Defined in auto-generated files.  */
 void init_registers_aarch64 (void);
@@ -208,36 +209,20 @@ struct arch_lwp_info
 static int aarch64_num_bp_regs;
 static int aarch64_num_wp_regs;
 
-/* Hardware breakpoint/watchpoint types.
-   The values map to their encodings in the bit 4 and bit 3 of the
-   hardware breakpoint/watchpoint control registers.  */
-
-enum target_point_type
-{
-  hw_execute = 0,		/* Execute HW breakpoint */
-  hw_read = 1,			/* Read    HW watchpoint */
-  hw_write = 2,			/* Common  HW watchpoint */
-  hw_access = 3,		/* Access  HW watchpoint */
-  point_type_unsupported
-};
-
 #define Z_PACKET_SW_BP '0'
 #define Z_PACKET_HW_BP '1'
 #define Z_PACKET_WRITE_WP '2'
 #define Z_PACKET_READ_WP '3'
 #define Z_PACKET_ACCESS_WP '4'
 
-/* Map the protocol breakpoint/watchpoint type TYPE to
-   enum target_point_type.  */
+/* Map the protocol breakpoint/watchpoint type TYPE to enum
+   target_hw_bp_type.  */
 
-static enum target_point_type
-Z_packet_to_point_type (char type)
+static enum target_hw_bp_type
+Z_packet_to_target_hw_bp_type (char type)
 {
   switch (type)
     {
-    case Z_PACKET_SW_BP:
-      /* Leave the handling of the sw breakpoint with the gdb client.  */
-      return point_type_unsupported;
     case Z_PACKET_HW_BP:
       return hw_execute;
     case Z_PACKET_WRITE_WP:
@@ -247,7 +232,7 @@ Z_packet_to_point_type (char type)
     case Z_PACKET_ACCESS_WP:
       return hw_access;
     default:
-      return point_type_unsupported;
+      fatal ("bad watchpoint type %c", type);
     }
 }
 
@@ -358,7 +343,7 @@ aarch64_breakpoint_at (CORE_ADDR where)
 static void
 aarch64_show_debug_reg_state (struct aarch64_debug_reg_state *state,
 			      const char *func, CORE_ADDR addr,
-			      int len, enum target_point_type type)
+			      int len, enum target_hw_bp_type type)
 {
   int i;
 
@@ -448,12 +433,31 @@ aarch64_watchpoint_length (unsigned int ctrl)
    breakpoint/watchpoint control register.  */
 
 static unsigned int
-aarch64_point_encode_ctrl_reg (enum target_point_type type, int len)
+aarch64_point_encode_ctrl_reg (enum target_hw_bp_type type, int len)
 {
-  unsigned int ctrl;
+  unsigned int ctrl, ttype;
 
   /* type */
-  ctrl = type << 3;
+  switch (type)
+    {
+    case hw_write:
+      ttype = 2;
+      break;
+    case hw_read:
+      ttype = 1;
+      break;
+    case hw_access:
+      ttype = 3;
+      break;
+    case hw_execute:
+      ttype = 0;
+      break;
+    default:
+      perror_with_name (_("Unrecognized breakpoint/watchpoint type"));
+    }
+
+  /* type */
+  ctrl = ttype << 3;
   /* length bitmask */
   ctrl |= ((1 << len) - 1) << 5;
   /* enabled at el0 */
@@ -749,7 +753,7 @@ aarch64_get_debug_reg_state ()
 
 static int
 aarch64_dr_state_insert_one_point (struct aarch64_debug_reg_state *state,
-				   enum target_point_type type,
+				   enum target_hw_bp_type type,
 				   CORE_ADDR addr, int len)
 {
   int i, idx, num_regs, is_watchpoint;
@@ -822,7 +826,7 @@ aarch64_dr_state_insert_one_point (struct aarch64_debug_reg_state *state,
 
 static int
 aarch64_dr_state_remove_one_point (struct aarch64_debug_reg_state *state,
-				   enum target_point_type type,
+				   enum target_hw_bp_type type,
 				   CORE_ADDR addr, int len)
 {
   int i, num_regs, is_watchpoint;
@@ -876,7 +880,7 @@ aarch64_dr_state_remove_one_point (struct aarch64_debug_reg_state *state,
 }
 
 static int
-aarch64_handle_breakpoint (enum target_point_type type, CORE_ADDR addr,
+aarch64_handle_breakpoint (enum target_hw_bp_type type, CORE_ADDR addr,
 			   int len, int is_insert)
 {
   struct aarch64_debug_reg_state *state;
@@ -898,7 +902,7 @@ aarch64_handle_breakpoint (enum target_point_type type, CORE_ADDR addr,
    from that it is an aligned watchpoint to be handled.  */
 
 static int
-aarch64_handle_aligned_watchpoint (enum target_point_type type,
+aarch64_handle_aligned_watchpoint (enum target_hw_bp_type type,
 				   CORE_ADDR addr, int len, int is_insert)
 {
   struct aarch64_debug_reg_state *state;
@@ -919,7 +923,7 @@ aarch64_handle_aligned_watchpoint (enum target_point_type type,
    Return 0 if succeed.  */
 
 static int
-aarch64_handle_unaligned_watchpoint (enum target_point_type type,
+aarch64_handle_unaligned_watchpoint (enum target_hw_bp_type type,
 				     CORE_ADDR addr, int len, int is_insert)
 {
   struct aarch64_debug_reg_state *state
@@ -956,7 +960,7 @@ aarch64_handle_unaligned_watchpoint (enum target_point_type type,
 }
 
 static int
-aarch64_handle_watchpoint (enum target_point_type type, CORE_ADDR addr,
+aarch64_handle_watchpoint (enum target_hw_bp_type type, CORE_ADDR addr,
 			   int len, int is_insert)
 {
   if (aarch64_point_is_aligned (1 /* is_watchpoint */ , addr, len))
@@ -965,6 +969,22 @@ aarch64_handle_watchpoint (enum target_point_type type, CORE_ADDR addr,
     return aarch64_handle_unaligned_watchpoint (type, addr, len, is_insert);
 }
 
+static int
+aarch64_supports_z_point_type (char z_type)
+{
+  switch (z_type)
+    {
+    case Z_PACKET_HW_BP:
+    case Z_PACKET_WRITE_WP:
+    case Z_PACKET_READ_WP:
+    case Z_PACKET_ACCESS_WP:
+      return 1;
+    default:
+      /* Leave the handling of sw breakpoints with the gdb client.  */
+      return 0;
+    }
+}
+
 /* Insert a hardware breakpoint/watchpoint.
    It actually only records the info of the to-be-inserted bp/wp;
    the actual insertion will happen when threads are resumed.
@@ -977,16 +997,17 @@ static int
 aarch64_insert_point (char type, CORE_ADDR addr, int len)
 {
   int ret;
-  enum target_point_type targ_type;
+  enum target_hw_bp_type targ_type;
+
+  if (!aarch64_supports_z_point_type (type))
+    return 1;
 
   if (debug_hw_points)
     fprintf (stderr, "insert_point on entry (addr=0x%08lx, len=%d)\n",
 	     (unsigned long) addr, len);
 
   /* Determine the type from the packet.  */
-  targ_type = Z_packet_to_point_type (type);
-  if (targ_type == point_type_unsupported)
-    return 1;
+  targ_type = Z_packet_to_target_hw_bp_type (type);
 
   if (targ_type != hw_execute)
     ret =
@@ -1014,16 +1035,17 @@ static int
 aarch64_remove_point (char type, CORE_ADDR addr, int len)
 {
   int ret;
-  enum target_point_type targ_type;
+  enum target_hw_bp_type targ_type;
+
+  if (!aarch64_supports_z_point_type (type))
+    return 1;
 
   if (debug_hw_points)
     fprintf (stderr, "remove_point on entry (addr=0x%08lx, len=%d)\n",
 	     (unsigned long) addr, len);
 
   /* Determine the type from the packet.  */
-  targ_type = Z_packet_to_point_type (type);
-  if (targ_type == point_type_unsupported)
-    return 1;
+  targ_type = Z_packet_to_target_hw_bp_type (type);
 
   /* Set up state pointers.  */
   if (targ_type != hw_execute)
-- 
1.7.11.7