The point of these changes is to avoid reading the frame pointer

	and stack pointer during stepping, to speed things up.
	A.  Changes to not select a frame until we need a selected frame:
	    * blockframe.c (flush_cached_frames): Call select_frame (NULL, -1).
	    * infrun.c (wait_for_inferior): Move call to select_frame back to
	    normal_stop.  This reverts a change of 13 Apr 94 (it says Jeff
	    Law, but the change was my idea); the only reason for that change
	    was so we could save and restore the selected frame in
	    wait_for_inferior, and now that flush_cached frames clears the
	    selected frame, that should work OK now.
	B.  Changes to not create a current_frame until we need one:
	    * blockframe.c (get_current_frame): If current_frame is NULL, try
	    to create an innermost frame.
	    * sparc-tdep.c (sparc_pop_frame), infcmd.c (run-stack_dummy),
	    infrun.c (wait_for_inferior), thread.c (thread_switch),
	    convex-tdep.c (set_thread_command), a29k-tdep.c (pop_frame),
	    alpha-tdep.c (alpha_pop_frame), convex-xdep.c (core_file_command),
	    h8300-tdep.c (h8300_pop_frame), h8500-tdep.c (h8300_pop_frame),
	    hppa-tdep.c (hppa_pop_frame), i386-tdep.c (i386_pop_frame),
	    i960-tdep.c (pop_frame), m68k-tdep.c
	    (m68k_pop_frame), mips-tdep.c (mips_pop_frame), rs6000-tdep.c
	    (push_dummy_frame, pop_dummy_frame, pop_frame), sh-tdep.c
	    (pop_frame), config/arm/tm-arm.h (POP_FRAME),
	    config/convex/tm-convex.h (POP_FRAME), config/gould/tm-pn.h
	    (POP_FRAME), config/ns32k/tm-merlin.h (POP_FRAME),
	    config/ns32k/tm-umax.h (POP_FRAME), config/tahoe/tm-tahoe.h
	    (POP_FRAME), config/vax/tm-vax.h (POP_FRAME): Don't
	    call create_new_frame.
	    * corelow.c (core_open), altos-xdep.c (core_file_command),
	    arm-xdep.c (core_file_command), gould-xdep.c (core_file_command),
	    m3-nat.c (select_thread), sun386-nat.c (core_file_command),
	    umax-xdep.c (core_file_command): Don't call create_new_frame; do
	    call flush_cached_frames.
	    * blockframe.c (reinit_frame_cache): Don't call create_new_frame
	    or select_frame.
	C.  Changes to get rid of stop_frame_address and instead only
	fetch the frame pointer when we need it.
	    * breakpoint.c (bpstat_stop_status): Remove argument
	    frame_address; use FRAME_FP (get_current_frame ()).
	    * infrun.c (wait_for_inferior): Don't pass frame pointer to
	    bpstat_stop_status.
	    * infrun.c (wait_for_inferior): Use FRAME_FP (get_current_frame
	    ()) instead of stop_frame_address.
	    * infrun.c (save_inferior_status, restore_inferior_status),
	    inferior.h (struct inferior_status): Don't save and restore
	    stop_frame_address.
	    * inferior.h, infcmd.c, thread.c (thread_switch), m3-nat.c
	    (select_thread): Remove stop_frame_address and uses thereof.
	D.  Same thing for the stack pointer.
	    * infrun.c (wait_for_inferior): Remove stop_sp and replace
	    uses thereof with read_sp ().
	E.  Change to eliminate one nasty little spot where we were
	wanting to know the frame pointer from before the current step
	(idea from GDB 3.5, which saved my ass, because my other ideas of
	how to fix it were very baroque).
	    * infrun.c: Remove prev_frame_address.
	    * infrun.c (wait_for_inferior, step_over_function): Use
	    step_frame_address instead of prev_frame_address.
	F.  Same basic idea for the stack pointer.
	    * inferior.h, infcmd.c: New variable step_sp.
	    * infcmd.c (step_1, until_next_command): Set it.
	    * infrun.c: Remove prev_sp and replace uses by step_sp.
	    * infrun.c (wait_for_inferior): If we get out of the step
	    range, then set step_sp to the current stack pointer before we
	    start going again.

1 files changed, 23 insertions, 15 deletions

diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index ff97d3a..1867b9a 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -134,10 +134,6 @@ enum target_signal stop_signal;
 
 CORE_ADDR stop_pc;
 
-/* Stack frame when program stopped.  */
-
-FRAME_ADDR stop_frame_address;
-
 /* Chain containing status of breakpoint(s) that we have stopped at.  */
 
 bpstat stop_bpstat;
@@ -173,6 +169,10 @@ CORE_ADDR step_range_end; /* Exclusive */
 
 FRAME_ADDR step_frame_address;
 
+/* Our notion of the current stack pointer.  */
+
+CORE_ADDR step_sp;
+
 /* 1 means step over all subroutine calls.
    0 means don't step over calls (used by stepi).
    -1 means step over calls to undebuggable functions.  */
@@ -212,7 +212,6 @@ run_command (args, from_tty)
 
   dont_repeat ();
 
-  /* Shouldn't this be target_has_execution?  FIXME.  */
   if (inferior_pid)
     {
       if (
@@ -369,6 +368,7 @@ step_1 (skip_subroutines, single_inst, count_string)
       if (!fr)				/* Avoid coredump here.  Why tho? */
 	error ("No current frame");
       step_frame_address = FRAME_FP (fr);
+      step_sp = read_sp ();
 
       if (! single_inst)
 	{
@@ -587,7 +587,6 @@ run_stack_dummy (addr, buffer)
        frame in case there is only one copy of the dummy (e.g.
        CALL_DUMMY_LOCATION == AFTER_TEXT_END).  */
     flush_cached_frames ();
-    set_current_frame (create_new_frame (read_fp (), sal.pc));
 
     /* If defined, CALL_DUMMY_BREAKPOINT_OFFSET is where we need to put
        a breakpoint instruction.  If not, the call dummy already has the
@@ -670,7 +669,8 @@ until_next_command (from_tty)
   
   step_over_calls = 1;
   step_frame_address = FRAME_FP (frame);
-  
+  step_sp = read_sp ();
+
   step_multi = 0;		/* Only one call to proceed */
   
   proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1);
@@ -976,15 +976,18 @@ const char * const reg_names[] = REGISTER_NAMES;
    to provide that format.  */  
 
 #if !defined (DO_REGISTERS_INFO)
+
 #define DO_REGISTERS_INFO(regnum, fp) do_registers_info(regnum, fp)
+
 static void
 do_registers_info (regnum, fpregs)
      int regnum;
      int fpregs;
 {
   register int i;
+  int numregs = ARCH_NUM_REGS;
 
-  for (i = 0; i < NUM_REGS; i++)
+  for (i = 0; i < numregs; i++)
     {
       char raw_buffer[MAX_REGISTER_RAW_SIZE];
       char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
@@ -1021,13 +1024,17 @@ do_registers_info (regnum, fpregs)
 		REGISTER_VIRTUAL_SIZE (i));
 
       /* If virtual format is floating, print it that way, and in raw hex.  */
-      if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (i)) == TYPE_CODE_FLT
-	  && ! INVALID_FLOAT (virtual_buffer, REGISTER_VIRTUAL_SIZE (i)))
+      if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (i)) == TYPE_CODE_FLT)
 	{
 	  register int j;
 
-	  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0,
-		     gdb_stdout, 0, 1, 0, Val_pretty_default);
+#ifdef INVALID_FLOAT
+	  if (INVALID_FLOAT (virtual_buffer, REGISTER_VIRTUAL_SIZE (i)))
+	    printf_filtered ("<invalid float>");
+	  else
+#endif
+	    val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0,
+		       gdb_stdout, 0, 1, 0, Val_pretty_default);
 
 	  printf_filtered ("\t(raw 0x");
 	  for (j = 0; j < REGISTER_RAW_SIZE (i); j++)
@@ -1072,7 +1079,7 @@ registers_info (addr_exp, fpregs)
      char *addr_exp;
      int fpregs;
 {
-  int regnum;
+  int regnum, numregs;
   register char *end;
 
   if (!target_has_registers)
@@ -1091,13 +1098,14 @@ registers_info (addr_exp, fpregs)
       end = addr_exp;
       while (*end != '\0' && *end != ' ' && *end != '\t')
 	++end;
-      for (regnum = 0; regnum < NUM_REGS; regnum++)
+      numregs = ARCH_NUM_REGS;
+      for (regnum = 0; regnum < numregs; regnum++)
 	if (!strncmp (addr_exp, reg_names[regnum], end - addr_exp)
 	    && strlen (reg_names[regnum]) == end - addr_exp)
 	  goto found;
       if (*addr_exp >= '0' && *addr_exp <= '9')
 	regnum = atoi (addr_exp);		/* Take a number */
-      if (regnum >= NUM_REGS)		/* Bad name, or bad number */
+      if (regnum >= numregs)		/* Bad name, or bad number */
 	error ("%.*s: invalid register", end - addr_exp, addr_exp);
 
 found: