[rfc] Convert SOFTWARE_SINGLE_STEP to multi-arch

[Andrew Cagney <ac131313@cygnus.com>]

Hello,

Attatched is a greatly simplified version of the multi-arch
SOFTWARE_SINGLE_STEP patch (I stripped out anything that wasn't directly
related).

The only thing of note is that, for the SPARC, its multi-arch status is
dropped back to partial.  This is because the sparc targets havn't had
SOFTWARE_SINGLE_STEP converted to multi-arch.  Before / after tests on
Solaris sparc32/sparc64 showed no regressions.

	Andrew
Mon Feb  5 10:33:15 2001  Andrew Cagney  <cagney@redhat.com>

	* config/sparc/tm-sp64.h (GDB_MULTI_ARCH): Down grade to
 	GDB_MULTI_ARCH_PARTIAL from two.  SOFTWARE_SINGLE_STEP is not
 	multi-arch.

	* gdbarch.sh (SOFTWARE_SINGLE_STEP): Add.
	* gdbarch.h, gdbarch.c: Re-generate.

	* target.h (SOFTWARE_SINGLE_STEP_P)
	(SOFTWARE_SINGLE_STEP): Delete macro definitions.

Index: gdbarch.sh
===================================================================
RCS file: /cvs/src/src/gdb/gdbarch.sh,v
retrieving revision 1.57
diff -p -r1.57 gdbarch.sh
*** gdbarch.sh	2001/03/21 19:47:44	1.57
--- gdbarch.sh	2001/03/23 02:21:28
*************** v:2:TARGET_FLOAT_FORMAT:const struct flo
*** 510,515 ****
--- 510,524 ----
  v:2:TARGET_DOUBLE_FORMAT:const struct floatformat *:double_format::::::default_double_format (gdbarch)
  v:2:TARGET_LONG_DOUBLE_FORMAT:const struct floatformat *:long_double_format::::::&floatformat_unknown
  f:2:CONVERT_FROM_FUNC_PTR_ADDR:CORE_ADDR:convert_from_func_ptr_addr:CORE_ADDR addr:addr:::default_convert_from_func_ptr_addr::0
+ # FIXME/cagney/2001-01-18: This should be split in two.  A target method that indicates if
+ # the target needs software single step.  An ISA method to implement it.
+ #
+ # FIXME/cagney/2001-01-18: This should be replaced with something that inserts breakpoints
+ # using the breakpoint system instead of blatting memory directly (as with rs6000).
+ #
+ # FIXME/cagney/2001-01-18: The logic is backwards.  It should be asking if the target can
+ # single step.  If not, then implement single step using breakpoints.
+ F:2:SOFTWARE_SINGLE_STEP:void:software_single_step:enum target_signal sig, int insert_breakpoints_p:sig, insert_breakpoints_p::0:0
  EOF
  }
  
Index: target.h
===================================================================
RCS file: /cvs/src/src/gdb/target.h,v
retrieving revision 1.16
diff -p -r1.16 target.h
*** target.h	2001/03/21 18:31:47	1.16
--- target.h	2001/03/23 02:21:28
*************** extern void push_remote_target (char *na
*** 1251,1262 ****
  \f
  /* Imported from machine dependent code */
  
- #ifndef SOFTWARE_SINGLE_STEP_P
- #define SOFTWARE_SINGLE_STEP_P() 0
- #define SOFTWARE_SINGLE_STEP(sig,bp_p)	\
-      (internal_error (__FILE__, __LINE__, "SOFTWARE_SINGLE_STEP"), 0)
- #endif /* SOFTWARE_SINGLE_STEP_P */
- 
  /* Blank target vector entries are initialized to target_ignore. */
  void target_ignore (void);
  
--- 1251,1256 ----
Index: config/sparc/tm-sp64.h
===================================================================
RCS file: /cvs/src/src/gdb/config/sparc/tm-sp64.h,v
retrieving revision 1.4
diff -p -r1.4 tm-sp64.h
*** tm-sp64.h	2001/03/06 08:21:37	1.4
--- tm-sp64.h	2001/03/23 02:21:30
***************
*** 23,29 ****
     Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.  */
  
! #define GDB_MULTI_ARCH 2
  
  #ifndef GDB_TARGET_IS_SPARC64
  #define GDB_TARGET_IS_SPARC64 1
--- 23,29 ----
     Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.  */
  
! #define GDB_MULTI_ARCH GDB_MULTI_ARCH_PARTIAL
  
  #ifndef GDB_TARGET_IS_SPARC64
  #define GDB_TARGET_IS_SPARC64 1
From eliz@delorie.com Fri Mar 23 02:49:00 2001
From: Eli Zaretskii <eliz@delorie.com>
To: msnyder@cygnus.com
Cc: ezannoni@cygnus.com, gdb-patches@sources.redhat.com
Subject: Re: Tracepoints documentation
Date: Fri, 23 Mar 2001 02:49:00 -0000
Message-id: <200103231048.FAA29295@indy.delorie.com>
References: <Pine.SUN.3.91.1010322100037.7564H-100000@is> <3ABA52B0.EE934756@cygnus.com>
X-SW-Source: 2001-03/msg00428.html
Content-length: 786

> Date: Thu, 22 Mar 2001 11:29:52 -0800
> From: Michael Snyder <msnyder@cygnus.com>
> 
> "Introspect" is sort of a code name for the tracing functionality of GDB.
> However, you do need a special target "stub" (a gdbserver or something like it)
> that knows how to perform the tracing stuff, since most of the tracing work
> is done on the target side.
> 
> We (the old Cygnus) had one customer who implemented their own target-side
> tracing server.  We also wrote a sort-of reference implementation ourselves,
> but it has never been released.

Thanks for the info.

From the patches you post from time to time, I understand that
tracepoint.c is actively maintained, which means it is used.  Is it
used in conjunction with that single target-side server which supports
tracepoints?