[framebase branch] Make d10v's frame ID constant

[Andrew Cagney <ac131313 at redhat dot com>]

Hello,

This patch changes the d10v so that its frame id is constant.  Part of 
this means stopping a prologue analysis at the frame's current instruction.

It also converts two FRAME_ARGS_ADDRESS() methods to 
get_frame_args_address().

committed to the framebase branch,
Andrew

2003-03-30  Andrew Cagney  <cagney at redhat dot com>

	* findvar.c (read_var_value): Use get_frame_args_address.
	
	* d10v-tdep.c (d10v_gdbarch_init): Do not set fp_regnum.
	(D10V_FP_REGNUM): Rename _FP_REGNUM and FP_REGNUM.
	(struct d10v_unwind_cache): Add the fields "prev_sp" and
	"this_func".  Update comment for base.
	(d10v_frame_unwind_cache): Set "prev_sp" and "this_func".
	(d10v_frame_this_id): Use the previous frame's inner most stack
	address and this frame's func address for the frame ID.  Use
	frame_id_build.  Don't analyze beyond the current instruction.

Index: d10v-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/d10v-tdep.c,v
retrieving revision 1.90.2.2
diff -u -r1.90.2.2 d10v-tdep.c
--- d10v-tdep.c	30 Mar 2003 16:35:20 -0000	1.90.2.2
+++ d10v-tdep.c	31 Mar 2003 03:42:44 -0000
@@ -69,7 +69,7 @@
   {
     R0_REGNUM = 0,
     R3_REGNUM = 3,
-    _FP_REGNUM = 11,
+    D10V_FP_REGNUM = 11,
     LR_REGNUM = 13,
     _SP_REGNUM = 15,
     PSW_REGNUM = 16,
@@ -346,7 +346,7 @@
 {
   if (reg_nr == PC_REGNUM)
     return builtin_type_void_func_ptr;
-  if (reg_nr == _SP_REGNUM || reg_nr == _FP_REGNUM)
+  if (reg_nr == _SP_REGNUM || reg_nr == D10V_FP_REGNUM)
     return builtin_type_void_data_ptr;
   else if (reg_nr >= A0_REGNUM
       && reg_nr < (A0_REGNUM + NR_A_REGS))
@@ -599,7 +599,12 @@
 struct d10v_unwind_cache
 {
   CORE_ADDR return_pc;
-  /* The frame's base.  Used when constructing a frame ID.  */
+  /* The previous frame's inner most stack address.  Used as this
+     frame ID's stack_addr.  */
+  CORE_ADDR prev_sp;
+  /* The function that belongs to this frame.  */
+  CORE_ADDR this_func;
+  /* The frame's base, optionally used by the high-level debug info.  */
   CORE_ADDR base;
   int size;
   CORE_ADDR *saved_regs;
@@ -716,10 +721,13 @@
   info->return_pc = 0;
   info->sp_offset = 0;
 
-  pc = get_pc_function_start (frame_pc_unwind (next_frame));
+  info->this_func = get_pc_function_start (frame_pc_unwind (next_frame));
+  pc = info->this_func;
 
   info->uses_frame = 0;
-  while (1)
+  for (pc = info->this_func;
+       pc < frame_pc_unwind (next_frame);
+       pc += 4)
     {
       op = (unsigned long) read_memory_integer (pc, 4);
       if ((op & 0xC0000000) == 0xC0000000)
@@ -766,7 +774,6 @@
 	      || !prologue_find_regs (info, op2, pc))
 	    break;
 	}
-      pc += 4;
     }
 
   info->size = -info->sp_offset;
@@ -777,7 +784,7 @@
       /* The SP was moved to the FP.  This indicates that a new frame
          was created.  Get THIS frame's FP value by unwinding it from
          the next frame.  */
-      frame_unwind_unsigned_register (next_frame, FP_REGNUM, &this_base);
+      frame_unwind_unsigned_register (next_frame, D10V_FP_REGNUM, &this_base);
       /* The FP points at the last saved register.  Adjust the FP back
          to before the first saved register giving the SP.  */
       prev_sp = this_base + info->size;
@@ -800,14 +807,14 @@
     }
 
   info->base = d10v_make_daddr (this_base);
-  prev_sp = d10v_make_daddr (prev_sp);
+  info->prev_sp = d10v_make_daddr (prev_sp);
 
   /* Adjust all the saved registers so that they contain addresses and
      not offsets.  */
   for (i = 0; i < NUM_REGS - 1; i++)
     if (info->saved_regs[i])
       {
-	info->saved_regs[i] = (prev_sp + info->saved_regs[i]);
+	info->saved_regs[i] = (info->prev_sp + info->saved_regs[i]);
       }
 
   if (info->saved_regs[LR_REGNUM])
@@ -826,7 +833,7 @@
 
   /* The SP_REGNUM is special.  Instead of the address of the SP, the
      previous frame's SP value is saved.  */
-  info->saved_regs[SP_REGNUM] = prev_sp;
+  info->saved_regs[SP_REGNUM] = info->prev_sp;
 
   return info;
 }
@@ -953,7 +960,7 @@
 static CORE_ADDR
 d10v_read_fp (void)
 {
-  return (d10v_make_daddr (read_register (FP_REGNUM)));
+  return (d10v_make_daddr (read_register (D10V_FP_REGNUM)));
 }
 
 /* When arguments must be pushed onto the stack, they go on in reverse
@@ -1451,9 +1458,6 @@
   CORE_ADDR base;
   CORE_ADDR pc;
 
-  /* Start with a NULL frame ID.  */
-  (*this_id) = null_frame_id;
-
   /* The PC is easy.  */
   pc = frame_pc_unwind (next_frame);
 
@@ -1465,7 +1469,7 @@
   /* Hopefully the prologue analysis either correctly determined the
      frame's base (which is the SP from the previous frame), or set
      that base to "NULL".  */
-  base = info->base;
+  base = info->prev_sp;
   if (base == STACK_START || base == 0)
     return;
 
@@ -1479,8 +1483,7 @@
       && get_frame_id (next_frame).base == base)
     return;
 
-  this_id->base = base;
-  this_id->pc = pc;
+  (*this_id) = frame_id_build (base, pc);
 }
 
 static void
@@ -1647,7 +1650,6 @@
 
   set_gdbarch_num_regs (gdbarch, d10v_num_regs);
   set_gdbarch_sp_regnum (gdbarch, 15);
-  set_gdbarch_fp_regnum (gdbarch, 11);
   set_gdbarch_pc_regnum (gdbarch, 18);
   set_gdbarch_register_name (gdbarch, d10v_register_name);
   set_gdbarch_register_size (gdbarch, 2);
Index: findvar.c
===================================================================
RCS file: /cvs/src/src/gdb/findvar.c,v
retrieving revision 1.52.4.1
diff -u -r1.52.4.1 findvar.c
--- findvar.c	26 Mar 2003 20:33:47 -0000	1.52.4.1
+++ findvar.c	31 Mar 2003 03:42:44 -0000
@@ -508,7 +508,7 @@
     case LOC_ARG:
       if (frame == NULL)
 	return 0;
-      addr = FRAME_ARGS_ADDRESS (frame);
+      addr = get_frame_args_address (frame);
       if (!addr)
 	return 0;
       addr += SYMBOL_VALUE (var);
@@ -520,7 +520,7 @@
 	CORE_ADDR argref;
 	if (frame == NULL)
 	  return 0;
-	argref = FRAME_ARGS_ADDRESS (frame);
+	argref = get_frame_args_address (frame);
 	if (!argref)
 	  return 0;
 	argref += SYMBOL_VALUE (var);