[rfc] Remove DEPRECATED_REMOTE_BREAKPOINT

["Ulrich Weigand" <uweigand at de dot ibm dot com>]

Hello,

this patch removes DEPRECATED_REMOTE_BREAKPOINT and its big/little endian
variants.  The macro is used if you need to use a different byte pattern
as breakpoint when using the remote target (as compared to the native target).
The only remaining user is tm-sh.h.

To remove the macro without changing the behaviour on SH, I've added a
check to sh_breakpoint_from_pc whether target_shortname is "remote",
and return the remote-specific breakpoint sequence in that case.

This is a bit weird, but there's some precedent for this method in
mips_breakpoint_from_pc, which also returns different byte patterns
depending on the value of target_shortname.

Tested by building a sh-netbsd cross-GDB.

I'd appreciate any feedback on this method -- did I overlook something
easier/better?

Bye,
Ulrich

ChangeLog:

	* config/sh/tm-sh.h (DEPRECATED_BIG_REMOTE_BREAKPOINT,
	DEPRECATED_LITTLE_REMOTE_BREAKPOINT): Remove.
	* doc/gdbint.texinfo: Remove mention of DEPRECATED_REMOTE_BREAKPOINT,
	DEPRECATED_BIG_REMOTE_BREAKPOINT, DEPRECATED_LITTLE_REMOTE_BREAKPOINT.
	* remote.c: Remove code under #ifdef DEPRECATED_REMOTE_BREAKPOINT,
	DEPRECATED_BIG_REMOTE_BREAKPOINT, DEPRECATED_LITTLE_REMOTE_BREAKPOINT.
	* sh-tdep.c (sh_breakpoint_from_pc): Return remote breakpoint
	sequence if target_shortname is "remote".


diff -ur gdb-orig/gdb/config/sh/tm-sh.h gdb-head/gdb/config/sh/tm-sh.h
--- gdb-orig/gdb/config/sh/tm-sh.h	2007-01-11 20:58:03.000000000 +0100
+++ gdb-head/gdb/config/sh/tm-sh.h	2007-02-28 02:35:36.420113032 +0100
@@ -23,7 +23,4 @@
 
 #define NUM_REALREGS 59 /* used in remote-e7000.c which is not multiarched. */
 
-#define DEPRECATED_BIG_REMOTE_BREAKPOINT    { 0xc3, 0x20 } /* Used in remote.c */
-#define DEPRECATED_LITTLE_REMOTE_BREAKPOINT { 0x20, 0xc3 } /* Used in remote.c */
-
 /*#define NOP   {0x20, 0x0b}*/ /* Who uses this???*/
diff -ur gdb-orig/gdb/doc/gdbint.texinfo gdb-head/gdb/doc/gdbint.texinfo
--- gdb-orig/gdb/doc/gdbint.texinfo	2007-02-22 16:00:08.000000000 +0100
+++ gdb-head/gdb/doc/gdbint.texinfo	2007-02-28 02:35:36.438110296 +0100
@@ -3321,18 +3321,6 @@
 @code{BIG_BREAKPOINT} and @code{LITTLE_BREAKPOINT} have been deprecated in
 favor of @code{BREAKPOINT_FROM_PC}.
 
-@item DEPRECATED_REMOTE_BREAKPOINT
-@itemx DEPRECATED_LITTLE_REMOTE_BREAKPOINT
-@itemx DEPRECATED_BIG_REMOTE_BREAKPOINT
-@findex DEPRECATED_BIG_REMOTE_BREAKPOINT
-@findex DEPRECATED_LITTLE_REMOTE_BREAKPOINT
-@findex DEPRECATED_REMOTE_BREAKPOINT
-Specify the breakpoint instruction sequence for a remote target.
-@code{DEPRECATED_REMOTE_BREAKPOINT},
-@code{DEPRECATED_BIG_REMOTE_BREAKPOINT} and
-@code{DEPRECATED_LITTLE_REMOTE_BREAKPOINT} have been deprecated in
-favor of @code{BREAKPOINT_FROM_PC} (@pxref{BREAKPOINT_FROM_PC}).
-
 @item BREAKPOINT_FROM_PC (@var{pcptr}, @var{lenptr})
 @findex BREAKPOINT_FROM_PC
 @anchor{BREAKPOINT_FROM_PC} Use the program counter to determine the
diff -ur gdb-orig/gdb/remote.c gdb-head/gdb/remote.c
--- gdb-orig/gdb/remote.c	2007-02-27 22:13:38.852048000 +0100
+++ gdb-head/gdb/remote.c	2007-02-28 02:35:36.489102544 +0100
@@ -5108,35 +5108,6 @@
 }
 
 
-/* On some machines, e.g. 68k, we may use a different breakpoint
-   instruction than other targets; in those use
-   DEPRECATED_REMOTE_BREAKPOINT instead of just BREAKPOINT_FROM_PC.
-   Also, bi-endian targets may define
-   DEPRECATED_LITTLE_REMOTE_BREAKPOINT and
-   DEPRECATED_BIG_REMOTE_BREAKPOINT.  If none of these are defined, we
-   just call the standard routines that are in mem-break.c.  */
-
-/* NOTE: cagney/2003-06-08: This is silly.  A remote and simulator
-   target should use an identical BREAKPOINT_FROM_PC.  As for native,
-   the ARCH-OS-tdep.c code can override the default.  */
-
-#if defined (DEPRECATED_LITTLE_REMOTE_BREAKPOINT) && defined (DEPRECATED_BIG_REMOTE_BREAKPOINT) && !defined(DEPRECATED_REMOTE_BREAKPOINT)
-#define DEPRECATED_REMOTE_BREAKPOINT
-#endif
-
-#ifdef DEPRECATED_REMOTE_BREAKPOINT
-
-/* If the target isn't bi-endian, just pretend it is.  */
-#if !defined (DEPRECATED_LITTLE_REMOTE_BREAKPOINT) && !defined (DEPRECATED_BIG_REMOTE_BREAKPOINT)
-#define DEPRECATED_LITTLE_REMOTE_BREAKPOINT DEPRECATED_REMOTE_BREAKPOINT
-#define DEPRECATED_BIG_REMOTE_BREAKPOINT DEPRECATED_REMOTE_BREAKPOINT
-#endif
-
-static unsigned char big_break_insn[] = DEPRECATED_BIG_REMOTE_BREAKPOINT;
-static unsigned char little_break_insn[] = DEPRECATED_LITTLE_REMOTE_BREAKPOINT;
-
-#endif /* DEPRECATED_REMOTE_BREAKPOINT */
-
 /* Insert a breakpoint.  On targets that have software breakpoint
    support, we ask the remote target to do the work; on targets
    which don't, we insert a traditional memory breakpoint.  */
@@ -5146,9 +5117,6 @@
 {
   CORE_ADDR addr = bp_tgt->placed_address;
   struct remote_state *rs = get_remote_state ();
-#ifdef DEPRECATED_REMOTE_BREAKPOINT
-  int val;
-#endif
 
   /* Try the "Z" s/w breakpoint packet if it is not already disabled.
      If it succeeds, then set the support to PACKET_ENABLE.  If it
@@ -5181,24 +5149,7 @@
 	}
     }
 
-#ifdef DEPRECATED_REMOTE_BREAKPOINT
-  bp_tgt->placed_size = bp_tgt->shadow_len = sizeof big_break_insn;
-  val = target_read_memory (addr, bp_tgt->shadow_contents, bp_tgt->shadow_len);
-
-  if (val == 0)
-    {
-      if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
-	val = target_write_memory (addr, (char *) big_break_insn,
-				   sizeof big_break_insn);
-      else
-	val = target_write_memory (addr, (char *) little_break_insn,
-				   sizeof little_break_insn);
-    }
-
-  return val;
-#else
   return memory_insert_breakpoint (bp_tgt);
-#endif /* DEPRECATED_REMOTE_BREAKPOINT */
 }
 
 static int
@@ -5226,12 +5177,7 @@
       return (rs->buf[0] == 'E');
     }
 
-#ifdef DEPRECATED_REMOTE_BREAKPOINT
-  return target_write_memory (bp_tgt->placed_address, bp_tgt->shadow_contents,
-			      bp_tgt->shadow_len);
-#else
   return memory_remove_breakpoint (bp_tgt);
-#endif /* DEPRECATED_REMOTE_BREAKPOINT */
 }
 
 static int
diff -ur gdb-orig/gdb/sh-tdep.c gdb-head/gdb/sh-tdep.c
--- gdb-orig/gdb/sh-tdep.c	2007-02-27 22:13:38.975029000 +0100
+++ gdb-head/gdb/sh-tdep.c	2007-02-28 02:35:36.534095704 +0100
@@ -389,6 +389,24 @@
   /* 0xc3c3 is trapa #c3, and it works in big and little endian modes */
   static unsigned char breakpoint[] = { 0xc3, 0xc3 };
 
+  /* For remote stub targets, trapa #20 is used.  */
+  if (strcmp (target_shortname, "remote") == 0)
+    {
+      static unsigned char big_remote_breakpoint[] = { 0xc3, 0x20 };
+      static unsigned char little_remote_breakpoint[] = { 0x20, 0xc3 };
+
+      if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+	{
+	  *lenptr = sizeof (big_remote_breakpoint);
+	  return big_remote_breakpoint;
+	}
+      else
+	{
+	  *lenptr = sizeof (little_remote_breakpoint);
+	  return little_remote_breakpoint;
+	}
+    }
+
   *lenptr = sizeof (breakpoint);
   return breakpoint;
 }
-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com