2003-07-01 Andrew Cagney <cagney@redhat.com>

	* trad-frame.h: Update comments, a -1 .addr is reserved.
	(trad_frame_value_p, trad_frame_addr_p): Declare.
	(trad_frame_reg_p): Declare.
	(trad_frame_set_value): Rename trad_frame_register_value.
	(trad_frame_set_unknown): Declare.
	* trad-frame.c (trad_frame_realreg_p): New function.
	(trad_frame_addr_p, trad_frame_value_p): New function.
	(trad_frame_set_unknown): New function.
	(trad_frame_alloc_saved_regs): Initialize .addr to -1, not zero.
	(trad_frame_prev_register): Use trad_frame_realreg_p,
	trad_frame_addr_p and trad_frame_value_p.
	(trad_frame_set_value): Rename trad_frame_register_value.
	* d10v-tdep.c (d10v_frame_unwind_cache): Use trad_frame_addr_p
	and trad_frame_set_value.

5 files changed, 132 insertions, 68 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d082c45..34d6db0 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,20 @@
+2003-07-01  Andrew Cagney  <cagney@redhat.com>
+
+	* trad-frame.h: Update comments, a -1 .addr is reserved.
+	(trad_frame_value_p, trad_frame_addr_p): Declare.
+	(trad_frame_reg_p): Declare.
+	(trad_frame_set_value): Rename trad_frame_register_value.
+	(trad_frame_set_unknown): Declare.
+	* trad-frame.c (trad_frame_realreg_p): New function.
+	(trad_frame_addr_p, trad_frame_value_p): New function.
+	(trad_frame_set_unknown): New function.
+	(trad_frame_alloc_saved_regs): Initialize .addr to -1, not zero.
+	(trad_frame_prev_register): Use trad_frame_realreg_p,
+	trad_frame_addr_p and trad_frame_value_p.
+	(trad_frame_set_value): Rename trad_frame_register_value.
+	* d10v-tdep.c (d10v_frame_unwind_cache): Use trad_frame_addr_p
+	and trad_frame_set_value.
+	
 2003-06-30  Jim Blandy  <jimb@redhat.com>
 
 	Patch from IBM (authors unspecified, probably Ulrich Weigand and
diff --git a/gdb/d10v-tdep.c b/gdb/d10v-tdep.c
index d522580..8a6df8e 100644
--- a/gdb/d10v-tdep.c
+++ b/gdb/d10v-tdep.c
@@ -763,7 +763,7 @@ d10v_frame_unwind_cache (struct frame_info *next_frame,
   /* 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].addr)
+    if (trad_frame_addr_p (info->saved_regs, i))
       {
 	info->saved_regs[i].addr = (info->prev_sp + info->saved_regs[i].addr);
       }
@@ -776,8 +776,8 @@ d10v_frame_unwind_cache (struct frame_info *next_frame,
 
   /* The previous frame's SP needed to be computed.  Save the computed
      value.  */
-  trad_frame_register_value (info->saved_regs, D10V_SP_REGNUM,
-			     d10v_make_daddr (prev_sp));
+  trad_frame_set_value (info->saved_regs, D10V_SP_REGNUM,
+			d10v_make_daddr (prev_sp));
 
   return info;
 }
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index 3b98180..a639b17 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -41,6 +41,7 @@
 #include "symtab.h"
 #include "target.h"
 #include "value.h"
+#include "trad-frame.h"
 
 #include "gdb_assert.h"
 #include "gdb_string.h"
@@ -248,8 +249,10 @@ struct i386_frame_cache
   CORE_ADDR sp_offset;
   CORE_ADDR pc;
 
-  /* Saved registers.  */
-  CORE_ADDR saved_regs[I386_NUM_SAVED_REGS];
+  /* Saved registers.  While trad-frame allocates space for the full
+     NUM_REGS + NUM_PSEUDOREGS, some of the code below cheats and
+     allocates space for only I386_NUM_SAVED_REGS.  */
+  struct trad_frame_saved_reg *saved_regs;
   CORE_ADDR saved_sp;
   int pc_in_eax;
 
@@ -260,7 +263,7 @@ struct i386_frame_cache
 /* Allocate and initialize a frame cache.  */
 
 static struct i386_frame_cache *
-i386_alloc_frame_cache (void)
+i386_alloc_frame_cache (struct frame_info *next_frame)
 {
   struct i386_frame_cache *cache;
   int i;
@@ -272,10 +275,7 @@ i386_alloc_frame_cache (void)
   cache->sp_offset = -4;
   cache->pc = 0;
 
-  /* Saved registers.  We initialize these to -1 since zero is a valid
-     offset (that's where %ebp is supposed to be stored).  */
-  for (i = 0; i < I386_NUM_SAVED_REGS; i++)
-    cache->saved_regs[i] = -1;
+  cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
   cache->saved_sp = 0;
   cache->pc_in_eax = 0;
 
@@ -449,7 +449,7 @@ i386_analyze_frame_setup (CORE_ADDR pc, CORE_ADDR current_pc,
     {
       /* Take into account that we've executed the `pushl %ebp' that
 	 starts this instruction sequence.  */
-      cache->saved_regs[I386_EBP_REGNUM] = 0;
+      cache->saved_regs[I386_EBP_REGNUM].addr = 0;
       cache->sp_offset += 4;
 
       /* If that's all, return now.  */
@@ -547,7 +547,7 @@ i386_analyze_register_saves (CORE_ADDR pc, CORE_ADDR current_pc,
 	  if (op < 0x50 || op > 0x57)
 	    break;
 
-	  cache->saved_regs[op - 0x50] = offset;
+	  cache->saved_regs[op - 0x50].addr = offset;
 	  offset -= 4;
 	  pc++;
 	}
@@ -609,6 +609,11 @@ i386_skip_prologue (CORE_ADDR start_pc)
   unsigned char op;
   int i;
 
+  /* Allocate space for the maximum number of saved registers.  This
+     should include all registers mentioned above, and %eip.  */
+  cache.saved_regs = alloca (I386_NUM_SAVED_REGS
+			     * sizeof (cache.saved_regs[0]));
+
   cache.locals = -1;
   pc = i386_analyze_prologue (start_pc, 0xffffffff, &cache);
   if (cache.locals < 0)
@@ -690,7 +695,7 @@ i386_frame_cache (struct frame_info *next_frame, void **this_cache)
   if (*this_cache)
     return *this_cache;
 
-  cache = i386_alloc_frame_cache ();
+  cache = i386_alloc_frame_cache (next_frame);
   *this_cache = cache;
 
   /* In principle, for normal frames, %ebp holds the frame pointer,
@@ -708,7 +713,7 @@ i386_frame_cache (struct frame_info *next_frame, void **this_cache)
     return cache;
 
   /* For normal frames, %eip is stored at 4(%ebp).  */
-  cache->saved_regs[I386_EIP_REGNUM] = 4;
+  cache->saved_regs[I386_EIP_REGNUM].addr = 4;
 
   cache->pc = frame_func_unwind (next_frame);
   if (cache->pc != 0)
@@ -735,8 +740,9 @@ i386_frame_cache (struct frame_info *next_frame, void **this_cache)
   /* Adjust all the saved registers such that they contain addresses
      instead of offsets.  */
   for (i = 0; i < I386_NUM_SAVED_REGS; i++)
-    if (cache->saved_regs[i] != -1)
-      cache->saved_regs[i] += cache->base;
+    if (cache->saved_regs[i].realnum >= 0
+	&& cache->saved_regs[i].addr != -1)
+      cache->saved_regs[i].addr += cache->base;
 
   return cache;
 }
@@ -824,23 +830,8 @@ i386_frame_prev_register (struct frame_info *next_frame, void **this_cache,
       return;
     }
 
-  if (regnum < I386_NUM_SAVED_REGS && cache->saved_regs[regnum] != -1)
-    {
-      *optimizedp = 0;
-      *lvalp = lval_memory;
-      *addrp = cache->saved_regs[regnum];
-      *realnump = -1;
-      if (valuep)
-	{
-	  /* Read the value in from memory.  */
-	  read_memory (*addrp, valuep,
-		       register_size (current_gdbarch, regnum));
-	}
-      return;
-    }
-
-  frame_register_unwind (next_frame, regnum,
-			 optimizedp, lvalp, addrp, realnump, valuep);
+  trad_frame_prev_register (next_frame, cache->saved_regs, regnum,
+			    optimizedp, lvalp, addrp, realnump, valuep);
 }
 
 static const struct frame_unwind i386_frame_unwind =
@@ -870,7 +861,7 @@ i386_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache)
   if (*this_cache)
     return *this_cache;
 
-  cache = i386_alloc_frame_cache ();
+  cache = i386_alloc_frame_cache (next_frame);
 
   frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
   cache->base = extract_unsigned_integer (buf, 4) - 4;
@@ -884,12 +875,12 @@ i386_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache)
 
       for (i = 0; i < tdep->sc_num_regs; i++)
 	if (tdep->sc_reg_offset[i] != -1)
-	  cache->saved_regs[i] = addr + tdep->sc_reg_offset[i];
+	  cache->saved_regs[i].addr = addr + tdep->sc_reg_offset[i];
     }
   else
     {
-      cache->saved_regs[I386_EIP_REGNUM] = addr + tdep->sc_pc_offset;
-      cache->saved_regs[I386_ESP_REGNUM] = addr + tdep->sc_sp_offset;
+      cache->saved_regs[I386_EIP_REGNUM].addr = addr + tdep->sc_pc_offset;
+      cache->saved_regs[I386_ESP_REGNUM].addr = addr + tdep->sc_sp_offset;
     }
 
   *this_cache = cache;
diff --git a/gdb/trad-frame.c b/gdb/trad-frame.c
index 92e6f83..d73813b 100644
--- a/gdb/trad-frame.c
+++ b/gdb/trad-frame.c
@@ -38,36 +38,70 @@ trad_frame_alloc_saved_regs (struct frame_info *next_frame)
   struct trad_frame_saved_reg *this_saved_regs
     = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
   for (regnum = 0; regnum < numregs; regnum++)
-    this_saved_regs[regnum].realnum = regnum;
+    {
+      this_saved_regs[regnum].realreg = regnum;
+      this_saved_regs[regnum].addr = -1;
+    }      
   return this_saved_regs;
 }
 
+enum { REG_VALUE = -1, REG_UNKNOWN = -2 };
+
+int
+trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
+{
+  return (this_saved_regs[regnum].realreg == REG_VALUE);
+}
+
+int
+trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
+{
+  return (this_saved_regs[regnum].realreg >= 0
+	  && this_saved_regs[regnum].addr != -1);
+}
+
+int
+trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
+		      int regnum)
+{
+  return (this_saved_regs[regnum].realreg >= 0
+	  && this_saved_regs[regnum].addr == -1);
+}
+
 void
-trad_frame_register_value (struct trad_frame_saved_reg this_saved_regs[],
-			   int regnum, LONGEST val)
+trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
+		      int regnum, LONGEST val)
 {
-  /* Make the REALNUM invalid, indicating that the ADDR contains the
+  /* Make the REALREG invalid, indicating that the ADDR contains the
      register's value.  */
-  this_saved_regs[regnum].realnum = -1;
+  this_saved_regs[regnum].realreg = REG_VALUE;
   this_saved_regs[regnum].addr = val;
 }
 
 void
+trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
+			int regnum)
+{
+  /* Make the REALREG invalid, indicating that the value is not known.  */
+  this_saved_regs[regnum].realreg = REG_UNKNOWN;
+  this_saved_regs[regnum].addr = -1;
+}
+
+void
 trad_frame_prev_register (struct frame_info *next_frame,
 			  struct trad_frame_saved_reg this_saved_regs[],
 			  int regnum, int *optimizedp,
 			  enum lval_type *lvalp, CORE_ADDR *addrp,
-			  int *realnump, void *bufferp)
+			  int *realregp, void *bufferp)
 {
   struct gdbarch *gdbarch = get_frame_arch (next_frame);
-  if (this_saved_regs[regnum].realnum >= 0
-      && this_saved_regs[regnum].addr != 0)
+  if (trad_frame_addr_p (this_saved_regs, regnum))
     {
       /* The register was saved in memory.  */
       *optimizedp = 0;
       *lvalp = lval_memory;
       *addrp = this_saved_regs[regnum].addr;
-      *realnump = -1;
+      *realregp = -1;
       if (bufferp != NULL)
 	{
 	  /* Read the value in from memory.  */
@@ -75,22 +109,26 @@ trad_frame_prev_register (struct frame_info *next_frame,
 			    register_size (gdbarch, regnum));
 	}
     }
-  else if (this_saved_regs[regnum].realnum >= 0
-	   && this_saved_regs[regnum].addr == 0)
+  else if (trad_frame_realreg_p (this_saved_regs, regnum))
     {
       /* As the next frame to return the value of the register.  */
-      frame_register_unwind (next_frame, this_saved_regs[regnum].realnum,
-			     optimizedp, lvalp, addrp, realnump, bufferp);
+      frame_register_unwind (next_frame, this_saved_regs[regnum].realreg,
+			     optimizedp, lvalp, addrp, realregp, bufferp);
     }
-  else
+  else if (trad_frame_value_p (this_saved_regs, regnum))
     {
       /* The register's value is available.  */
       *optimizedp = 0;
       *lvalp = not_lval;
       *addrp = 0;
-      *realnump = -1;
+      *realregp = -1;
       if (bufferp != NULL)
 	store_unsigned_integer (bufferp, register_size (gdbarch, regnum),
 				this_saved_regs[regnum].addr);
     }
+  else
+    {
+      error ("Register %s not available",
+	     gdbarch_register_name (gdbarch, regnum));
+    }
 }
diff --git a/gdb/trad-frame.h b/gdb/trad-frame.h
index 2b04c7e..55720c7 100644
--- a/gdb/trad-frame.h
+++ b/gdb/trad-frame.h
@@ -28,33 +28,51 @@ struct frame_info;
    the value of REGNUM for the previous frame can be found in this
    frame.
 
-   The table is initialized with an identity encoding (ADDR == 0,
-   REALNUM == REGNUM) indicating that the value of REGNUM in the
-   previous frame can be found in register REGNUM (== REALNUM) in this
+   The table is initialized with an identity encoding (ADDR == -1,
+   REALREG == REGNUM) indicating that the value of REGNUM in the
+   previous frame can be found in register REGNUM (== REALREG) in this
    frame.
 
    The initial encoding can then be changed:
 
-   Modify ADDR (REALNUM >= 0, ADDR != 0) to indicate that the value of
-   register REGNUM in the previous frame can be found in memory at
-   ADDR in this frame.
+   Modify ADDR (REALREG >= 0, ADDR != -1) to indicate that the value
+   of register REGNUM in the previous frame can be found in memory at
+   ADDR in this frame (addr_p, !realreg_p, !value_p).
 
-   Modify REALNUM (REALNUM >= 0, ADDR == 0) to indicate that the value
-   of register REGNUM in the previous frame is found in register
-   REALNUM in this frame.
+   Modify REALREG (REALREG >= 0, ADDR == -1) to indicate that the
+   value of register REGNUM in the previous frame is found in register
+   REALREG in this frame (!addr_p, realreg_p, !value_p).
 
-   Call trad_frame_register_value (REALNUM < 0) to indicate that the
-   value of register REGNUM in the previous frame is found in ADDR.  */
+   Call trad_frame_set_value (REALREG == -1) to indicate that the
+   value of register REGNUM in the previous frame is found in ADDR
+   (!addr_p, !realreg_p, value_p).
+
+   Call trad_frame_set_unknown (REALREG == -2) to indicate that the
+   register's value is not known.  */
 
 struct trad_frame_saved_reg
 {
   LONGEST addr; /* A CORE_ADDR fits in a longest.  */
-  int realnum;
+  int realreg;
 };
 
-/* Convenience function, encode REGNUM's location in the trad-frame.  */
-void trad_frame_register_value (struct trad_frame_saved_reg this_saved_regs[],
-				int regnum, LONGEST val);
+/* Encode REGNUM value in the trad-frame.  */
+void trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
+			   int regnum, LONGEST val);
+
+/* Mark REGNUM as unknown.  */
+void trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
+			     int regnum);
+
+/* Convenience functions, return non-zero if the register has been
+   encoded as specified.  */
+int trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[],
+			int regnum);
+int trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[],
+		       int regnum);
+int trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
+			  int regnum);
+
 
 /* Return a freshly allocated (and initialized) trad_frame array.  */
 struct trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct frame_info *next_frame);
@@ -65,6 +83,6 @@ void trad_frame_prev_register (struct frame_info *next_frame,
 			       struct trad_frame_saved_reg this_saved_regs[],
 			       int regnum, int *optimizedp,
 			       enum lval_type *lvalp, CORE_ADDR *addrp,
-			       int *realnump, void *bufferp);
+			       int *realregp, void *bufferp);
 
 #endif