2004-06-06 Randolph Chung <tausq@debian.org>

[deliverable/binutils-gdb.git] / gdb / avr-tdep.c

diff --git a/gdb/avr-tdep.c b/gdb/avr-tdep.c
index 688e8c72ca905d3836b02f9f3776676a9b5e340b..2b5db688f886202c4bb6b4e2150b96de96c87e1f 100644 (file)
--- a/gdb/avr-tdep.c
+++ b/gdb/avr-tdep.c
@@ -1,5 +1,5 @@
 /* Target-dependent code for Atmel AVR, for GDB.
 /* Target-dependent code for Atmel AVR, for GDB.

-   Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002
+   Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004

    Free Software Foundation, Inc.
 
    This file is part of GDB.
    Free Software Foundation, Inc.
 
    This file is part of GDB.


@@ -19,12 +19,16 @@
    Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.  */
 
    Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.  */
 

-/* Contributed by Theodore A. Roth, troth@verinet.com */
+/* Contributed by Theodore A. Roth, troth@openavr.org */

 
 /* Portions of this file were taken from the original gdb-4.18 patch developed
    by Denis Chertykov, denisc@overta.ru */
 
 #include "defs.h"
 
 /* Portions of this file were taken from the original gdb-4.18 patch developed
    by Denis Chertykov, denisc@overta.ru */
 
 #include "defs.h"

+#include "frame.h"
+#include "frame-unwind.h"
+#include "frame-base.h"
+#include "trad-frame.h"

 #include "gdbcmd.h"
 #include "gdbcore.h"
 #include "inferior.h"
 #include "gdbcmd.h"
 #include "gdbcore.h"
 #include "inferior.h"


@@ -32,6 +36,7 @@
 #include "arch-utils.h"
 #include "regcache.h"
 #include "gdb_string.h"
 #include "arch-utils.h"
 #include "regcache.h"
 #include "gdb_string.h"

+#include "dis-asm.h"

 
 /* AVR Background:
 
 
 /* AVR Background:
 


@@ -89,7 +94,7 @@ enum
 
   AVR_PC_REG_INDEX = 35,       /* index into array of registers */
 
 
   AVR_PC_REG_INDEX = 35,       /* index into array of registers */
 

-  AVR_MAX_PROLOGUE_SIZE = 56,  /* bytes */
+  AVR_MAX_PROLOGUE_SIZE = 64,  /* bytes */

 
   /* Count of pushed registers. From r2 to r17 (inclusively), r28, r29 */
   AVR_MAX_PUSHES = 18,
 
   /* Count of pushed registers. From r2 to r17 (inclusively), r28, r29 */
   AVR_MAX_PUSHES = 18,


@@ -97,6 +102,12 @@ enum
   /* Number of the last pushed register. r17 for current avr-gcc */
   AVR_LAST_PUSHED_REGNUM = 17,
 
   /* Number of the last pushed register. r17 for current avr-gcc */
   AVR_LAST_PUSHED_REGNUM = 17,
 

+  AVR_ARG1_REGNUM = 24,         /* Single byte argument */
+  AVR_ARGN_REGNUM = 25,         /* Multi byte argments */
+
+  AVR_RET1_REGNUM = 24,         /* Single byte return value */
+  AVR_RETN_REGNUM = 25,         /* Multi byte return value */
+

   /* FIXME: TRoth/2002-01-??: Can we shift all these memory masks left 8
      bits? Do these have to match the bfd vma values?. It sure would make
      things easier in the future if they didn't need to match.
   /* FIXME: TRoth/2002-01-??: Can we shift all these memory masks left 8
      bits? Do these have to match the bfd vma values?. It sure would make
      things easier in the future if they didn't need to match.


@@ -130,6 +141,20 @@ enum
 #endif
 };
 
 #endif
 };
 

+/* Prologue types:
+
+   NORMAL and CALL are the typical types (the -mcall-prologues gcc option
+   causes the generation of the CALL type prologues).  */
+
+enum {
+    AVR_PROLOGUE_NONE,              /* No prologue */
+    AVR_PROLOGUE_NORMAL,
+    AVR_PROLOGUE_CALL,              /* -mcall-prologues */
+    AVR_PROLOGUE_MAIN,
+    AVR_PROLOGUE_INTR,              /* interrupt handler */
+    AVR_PROLOGUE_SIG,               /* signal handler */
+};
+

 /* Any function with a frame looks like this
    .......    <-SP POINTS HERE
    LOCALS1    <-FP POINTS HERE
 /* Any function with a frame looks like this
    .......    <-SP POINTS HERE
    LOCALS1    <-FP POINTS HERE


@@ -141,14 +166,17 @@ enum
    FIRST ARG
    SECOND ARG */
 
    FIRST ARG
    SECOND ARG */
 

-struct frame_extra_info
+struct avr_unwind_cache

 {
 {

-  CORE_ADDR return_pc;
-  CORE_ADDR args_pointer;
-  int locals_size;
-  int framereg;
-  int framesize;
-  int is_main;
+  /* The previous frame's inner most stack address.  Used as this
+     frame ID's stack_addr.  */
+  CORE_ADDR prev_sp;
+  /* The frame's base, optionally used by the high-level debug info.  */
+  CORE_ADDR base;
+  int size;
+  int prologue_type;
+  /* Table indicating the location of each and every register.  */
+  struct trad_frame_saved_reg *saved_regs;

 };
 
 struct gdbarch_tdep
 };
 
 struct gdbarch_tdep


@@ -176,60 +204,18 @@ avr_register_name (int regnum)
   return register_names[regnum];
 }
 
   return register_names[regnum];
 }
 

-/* Index within `registers' of the first byte of the space for
-   register REGNUM.  */
-
-static int
-avr_register_byte (int regnum)
-{
-  if (regnum < AVR_PC_REGNUM)
-    return regnum;
-  else
-    return AVR_PC_REG_INDEX;
-}
-
-/* Number of bytes of storage in the actual machine representation for
-   register REGNUM.  */
-
-static int
-avr_register_raw_size (int regnum)
-{
-  switch (regnum)
-    {
-    case AVR_PC_REGNUM:
-      return 4;
-    case AVR_SP_REGNUM:
-    case AVR_FP_REGNUM:
-      return 2;
-    default:
-      return 1;
-    }
-}
-
-/* Number of bytes of storage in the program's representation
-   for register N.  */
-
-static int
-avr_register_virtual_size (int regnum)
-{
-  return TYPE_LENGTH (REGISTER_VIRTUAL_TYPE (regnum));
-}
-

 /* Return the GDB type object for the "standard" data type
    of data in register N.  */
 
 static struct type *
 /* Return the GDB type object for the "standard" data type
    of data in register N.  */
 
 static struct type *

-avr_register_virtual_type (int regnum)
+avr_register_type (struct gdbarch *gdbarch, int reg_nr)

 {
 {

-  switch (regnum)
-    {
-    case AVR_PC_REGNUM:
-      return builtin_type_unsigned_long;
-    case AVR_SP_REGNUM:
-      return builtin_type_unsigned_short;
-    default:
-      return builtin_type_unsigned_char;
-    }
+  if (reg_nr == AVR_PC_REGNUM)
+    return builtin_type_uint32;
+  if (reg_nr == AVR_SP_REGNUM)
+    return builtin_type_void_data_ptr;
+  else
+    return builtin_type_uint8;

 }
 
 /* Instruction address checks and convertions. */
 }
 
 /* Instruction address checks and convertions. */


@@ -240,12 +226,6 @@ avr_make_iaddr (CORE_ADDR x)
   return ((x) | AVR_IMEM_START);
 }
 
   return ((x) | AVR_IMEM_START);
 }
 

-static int
-avr_iaddr_p (CORE_ADDR x)
-{
-  return (((x) & AVR_MEM_MASK) == AVR_IMEM_START);
-}
-

 /* FIXME: TRoth: Really need to use a larger mask for instructions. Some
    devices are already up to 128KBytes of flash space.
 
 /* FIXME: TRoth: Really need to use a larger mask for instructions. Some
    devices are already up to 128KBytes of flash space.
 


@@ -265,12 +245,6 @@ avr_make_saddr (CORE_ADDR x)
   return ((x) | AVR_SMEM_START);
 }
 
   return ((x) | AVR_SMEM_START);
 }
 

-static int
-avr_saddr_p (CORE_ADDR x)
-{
-  return (((x) & AVR_MEM_MASK) == AVR_SMEM_START);
-}
-

 static CORE_ADDR
 avr_convert_saddr_to_raw (CORE_ADDR x)
 {
 static CORE_ADDR
 avr_convert_saddr_to_raw (CORE_ADDR x)
 {


@@ -311,7 +285,7 @@ avr_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
       || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD)
     {
       store_unsigned_integer (buf, TYPE_LENGTH (type),
       || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD)
     {
       store_unsigned_integer (buf, TYPE_LENGTH (type),

-                             avr_convert_iaddr_to_raw (addr));
+                             avr_convert_iaddr_to_raw (addr >> 1));

     }
   else
     {
     }
   else
     {


@@ -322,23 +296,15 @@ avr_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
 }
 
 static CORE_ADDR
 }
 
 static CORE_ADDR

-avr_pointer_to_address (struct type *type, void *buf)
+avr_pointer_to_address (struct type *type, const void *buf)

 {
 {

-  CORE_ADDR addr = extract_address (buf, TYPE_LENGTH (type));
-
-  if (TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))
-    {
-      fprintf_unfiltered (gdb_stderr, "CODE_SPACE ---->> ptr->addr: 0x%lx\n",
-                         addr);
-      fprintf_unfiltered (gdb_stderr,
-                         "+++ If you see this, please send me an email <troth@verinet.com>\n");
-    }
+  CORE_ADDR addr = extract_unsigned_integer (buf, TYPE_LENGTH (type));

 
   /* Is it a code address?  */
   if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
       || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD
       || TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))
 
   /* Is it a code address?  */
   if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
       || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD
       || TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))

-    return avr_make_iaddr (addr);
+    return avr_make_iaddr (addr << 1);

   else
     return avr_make_saddr (addr);
 }
   else
     return avr_make_saddr (addr);
 }


@@ -347,12 +313,12 @@ static CORE_ADDR
 avr_read_pc (ptid_t ptid)
 {
   ptid_t save_ptid;
 avr_read_pc (ptid_t ptid)
 {
   ptid_t save_ptid;

-  CORE_ADDR pc;
+  ULONGEST pc;

   CORE_ADDR retval;
 
   save_ptid = inferior_ptid;
   inferior_ptid = ptid;
   CORE_ADDR retval;
 
   save_ptid = inferior_ptid;
   inferior_ptid = ptid;

-  pc = (int) read_register (AVR_PC_REGNUM);
+  regcache_cooked_read_unsigned (current_regcache, AVR_PC_REGNUM, &pc);

   inferior_ptid = save_ptid;
   retval = avr_make_iaddr (pc);
   return retval;
   inferior_ptid = save_ptid;
   retval = avr_make_iaddr (pc);
   return retval;


@@ -372,128 +338,141 @@ avr_write_pc (CORE_ADDR val, ptid_t ptid)
 static CORE_ADDR
 avr_read_sp (void)
 {
 static CORE_ADDR
 avr_read_sp (void)
 {

-  return (avr_make_saddr (read_register (AVR_SP_REGNUM)));
-}
+  ULONGEST sp;

 
 

-static void
-avr_write_sp (CORE_ADDR val)
-{
-  write_register (AVR_SP_REGNUM, avr_convert_saddr_to_raw (val));
+  regcache_cooked_read_unsigned (current_regcache, AVR_SP_REGNUM, &sp);
+  return (avr_make_saddr (sp));

 }
 
 }
 

-static CORE_ADDR
-avr_read_fp (void)
-{
-  return (avr_make_saddr (read_register (AVR_FP_REGNUM)));
-}
-
-/* Translate a GDB virtual ADDR/LEN into a format the remote target
-   understands.  Returns number of bytes that can be transfered
-   starting at TARG_ADDR.  Return ZERO if no bytes can be transfered
-   (segmentation fault).
-
-   TRoth/2002-04-08: Could this be used to check for dereferencing an invalid
-   pointer? */
-
-static void
-avr_remote_translate_xfer_address (CORE_ADDR memaddr, int nr_bytes,
-                                  CORE_ADDR *targ_addr, int *targ_len)
+static int
+avr_scan_arg_moves (int vpc, unsigned char *prologue)

 {
 {

-  long out_addr;
-  long out_len;
-
-  /* FIXME: TRoth: Do nothing for now. Will need to examine memaddr at this
-     point and see if the high bit are set with the masks that we want. */
-
-  *targ_addr = memaddr;
-  *targ_len = nr_bytes;
-}
-
-/* Function pointers obtained from the target are half of what gdb expects so
-   multiply by 2. */
+  unsigned short insn;

 
 

-static CORE_ADDR
-avr_convert_from_func_ptr_addr (CORE_ADDR addr)
-{
-  return addr * 2;
+  for (; vpc < AVR_MAX_PROLOGUE_SIZE; vpc += 2)
+    {
+      insn = EXTRACT_INSN (&prologue[vpc]);
+      if ((insn & 0xff00) == 0x0100)   /* movw rXX, rYY */
+        continue;
+      else if ((insn & 0xfc00) == 0x2c00) /* mov rXX, rYY */
+        continue;
+      else
+          break;
+    }
+    
+  return vpc;

 }
 
 }
 

-/* avr_scan_prologue is also used as the frame_init_saved_regs().
-
-   Put here the code to store, into fi->saved_regs, the addresses of
-   the saved registers of frame described by FRAME_INFO.  This
-   includes special registers such as pc and fp saved in special ways
-   in the stack frame.  sp is even more special: the address we return
-   for it IS the sp for the next frame. */
+/* Function: avr_scan_prologue

 
 

-/* Function: avr_scan_prologue (helper function for avr_init_extra_frame_info)
-   This function decodes a AVR function prologue to determine:
+   This function decodes an AVR function prologue to determine:

      1) the size of the stack frame
      2) which registers are saved on it
      3) the offsets of saved regs
      1) the size of the stack frame
      2) which registers are saved on it
      3) the offsets of saved regs

-   This information is stored in the "extra_info" field of the frame_info.
-
-   A typical AVR function prologue might look like this:
-        push rXX
-        push r28
-        push r29
-        in r28,__SP_L__
-        in r29,__SP_H__
-        sbiw r28,<LOCALS_SIZE>
-        in __tmp_reg__,__SREG__
+   This information is stored in the avr_unwind_cache structure.
+
+   Some devices lack the sbiw instruction, so on those replace this:
+        sbiw    r28, XX
+   with this:
+        subi    r28,lo8(XX)
+        sbci    r29,hi8(XX)
+
+   A typical AVR function prologue with a frame pointer might look like this:
+        push    rXX        ; saved regs
+        ...
+        push    r28
+        push    r29
+        in      r28,__SP_L__
+        in      r29,__SP_H__
+        sbiw    r28,<LOCALS_SIZE>
+        in      __tmp_reg__,__SREG__

         cli
         cli

-        out __SP_L__,r28
-        out __SREG__,__tmp_reg__
-        out __SP_H__,r29
-
-  A `-mcall-prologues' prologue look like this:
-        ldi r26,<LOCALS_SIZE>
-        ldi r27,<LOCALS_SIZE>/265
-        ldi r30,pm_lo8(.L_foo_body)
-        ldi r31,pm_hi8(.L_foo_body)
-        rjmp __prologue_saves__+RRR
-  .L_foo_body:  */
+        out     __SP_H__,r29
+        out     __SREG__,__tmp_reg__
+        out     __SP_L__,r28
+
+   A typical AVR function prologue without a frame pointer might look like
+   this:
+        push    rXX        ; saved regs
+        ...
+
+   A main function prologue looks like this:
+        ldi     r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
+        ldi     r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
+        out     __SP_H__,r29
+        out     __SP_L__,r28
+
+   A signal handler prologue looks like this:
+        push    __zero_reg__
+        push    __tmp_reg__
+        in      __tmp_reg__, __SREG__
+        push    __tmp_reg__
+        clr     __zero_reg__
+        push    rXX             ; save registers r18:r27, r30:r31
+        ...
+        push    r28             ; save frame pointer
+        push    r29
+        in      r28, __SP_L__
+        in      r29, __SP_H__
+        sbiw    r28, <LOCALS_SIZE>
+        out     __SP_H__, r29
+        out     __SP_L__, r28
+        
+   A interrupt handler prologue looks like this:
+        sei
+        push    __zero_reg__
+        push    __tmp_reg__
+        in      __tmp_reg__, __SREG__
+        push    __tmp_reg__
+        clr     __zero_reg__
+        push    rXX             ; save registers r18:r27, r30:r31
+        ...
+        push    r28             ; save frame pointer
+        push    r29
+        in      r28, __SP_L__
+        in      r29, __SP_H__
+        sbiw    r28, <LOCALS_SIZE>
+        cli
+        out     __SP_H__, r29
+        sei     
+        out     __SP_L__, r28
+
+   A `-mcall-prologues' prologue looks like this (Note that the megas use a
+   jmp instead of a rjmp, thus the prologue is one word larger since jmp is a
+   32 bit insn and rjmp is a 16 bit insn):
+        ldi     r26,lo8(<LOCALS_SIZE>)
+        ldi     r27,hi8(<LOCALS_SIZE>)
+        ldi     r30,pm_lo8(.L_foo_body)
+        ldi     r31,pm_hi8(.L_foo_body)
+        rjmp    __prologue_saves__+RRR
+        .L_foo_body:  */
+
+/* Not really part of a prologue, but still need to scan for it, is when a
+   function prologue moves values passed via registers as arguments to new
+   registers. In this case, all local variables live in registers, so there
+   may be some register saves. This is what it looks like:
+        movw    rMM, rNN
+        ...
+
+   There could be multiple movw's. If the target doesn't have a movw insn, it
+   will use two mov insns. This could be done after any of the above prologue
+   types.  */

 
 

-static void
-avr_scan_prologue (struct frame_info *fi)
+static CORE_ADDR
+avr_scan_prologue (CORE_ADDR pc, struct avr_unwind_cache *info)

 {
 {

-  CORE_ADDR prologue_start;
-  CORE_ADDR prologue_end;

   int i;
   unsigned short insn;
   int i;
   unsigned short insn;

-  int regno;

   int scan_stage = 0;
   int scan_stage = 0;

-  char *name;

   struct minimal_symbol *msymbol;
   struct minimal_symbol *msymbol;

-  int prologue_len;

   unsigned char prologue[AVR_MAX_PROLOGUE_SIZE];
   int vpc = 0;
 
   unsigned char prologue[AVR_MAX_PROLOGUE_SIZE];
   int vpc = 0;
 

-  fi->extra_info->framereg = AVR_SP_REGNUM;
-
-  if (find_pc_partial_function
-      (fi->pc, &name, &prologue_start, &prologue_end))
-    {
-      struct symtab_and_line sal = find_pc_line (prologue_start, 0);
-
-      if (sal.line == 0)       /* no line info, use current PC */
-       prologue_end = fi->pc;
-      else if (sal.end < prologue_end) /* next line begins after fn end */
-       prologue_end = sal.end; /* (probably means no prologue)  */
-    }
-  else
-    /* We're in the boondocks: allow for */
-    /* 19 pushes, an add, and "mv fp,sp" */
-    prologue_end = prologue_start + AVR_MAX_PROLOGUE_SIZE;
-
-  prologue_end = min (prologue_end, fi->pc);
-
-  /* Search the prologue looking for instructions that set up the
-     frame pointer, adjust the stack pointer, and save registers.  */
-
-  fi->extra_info->framesize = 0;
-  prologue_len = prologue_end - prologue_start;
-  read_memory (prologue_start, prologue, prologue_len);
+  /* FIXME: TRoth/2003-06-11: This could be made more efficient by only
+     reading in the bytes of the prologue. The problem is that the figuring
+     out where the end of the prologue is is a bit difficult. The old code 
+     tried to do that, but failed quite often.  */
+  read_memory (pc, prologue, AVR_MAX_PROLOGUE_SIZE);

 
   /* Scanning main()'s prologue
      ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
 
   /* Scanning main()'s prologue
      ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)


@@ -501,7 +480,7 @@ avr_scan_prologue (struct frame_info *fi)
      out __SP_H__,r29
      out __SP_L__,r28 */
 
      out __SP_H__,r29
      out __SP_L__,r28 */
 

-  if (name && strcmp ("main", name) == 0 && prologue_len == 8)
+  if (1)

     {
       CORE_ADDR locals;
       unsigned char img[] = {
     {
       CORE_ADDR locals;
       unsigned char img[] = {


@@ -509,7 +488,6 @@ avr_scan_prologue (struct frame_info *fi)
        0xcd, 0xbf              /* out __SP_L__,r28 */
       };
 
        0xcd, 0xbf              /* out __SP_L__,r28 */
       };
 

-      fi->extra_info->framereg = AVR_FP_REGNUM;

       insn = EXTRACT_INSN (&prologue[vpc]);
       /* ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>) */
       if ((insn & 0xf0f0) == 0xe0c0)
       insn = EXTRACT_INSN (&prologue[vpc]);
       /* ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>) */
       if ((insn & 0xf0f0) == 0xe0c0)


@@ -522,94 +500,124 @@ avr_scan_prologue (struct frame_info *fi)
              locals |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
              if (memcmp (prologue + vpc + 4, img, sizeof (img)) == 0)
                {
              locals |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
              if (memcmp (prologue + vpc + 4, img, sizeof (img)) == 0)
                {

-                 fi->frame = locals;
-
-                 fi->extra_info->is_main = 1;
-                 return;
+                  info->prologue_type = AVR_PROLOGUE_MAIN;
+                  info->base = locals;
+                  return pc + 4;

                }
            }
        }
     }
 
   /* Scanning `-mcall-prologues' prologue
                }
            }
        }
     }
 
   /* Scanning `-mcall-prologues' prologue

-     FIXME: mega prologue have a 12 bytes long */
+     Classic prologue is 10 bytes, mega prologue is a 12 bytes long */

 
 

-  while (prologue_len <= 12)   /* I'm use while to avoit many goto's */
+  while (1)    /* Using a while to avoid many goto's */

     {
       int loc_size;
       int body_addr;
       unsigned num_pushes;
     {
       int loc_size;
       int body_addr;
       unsigned num_pushes;

+      int pc_offset = 0;

 
       insn = EXTRACT_INSN (&prologue[vpc]);
       /* ldi r26,<LOCALS_SIZE> */
       if ((insn & 0xf0f0) != 0xe0a0)
        break;
       loc_size = (insn & 0xf) | ((insn & 0x0f00) >> 4);
 
       insn = EXTRACT_INSN (&prologue[vpc]);
       /* ldi r26,<LOCALS_SIZE> */
       if ((insn & 0xf0f0) != 0xe0a0)
        break;
       loc_size = (insn & 0xf) | ((insn & 0x0f00) >> 4);

+      pc_offset += 2;

 
       insn = EXTRACT_INSN (&prologue[vpc + 2]);
       /* ldi r27,<LOCALS_SIZE> / 256 */
       if ((insn & 0xf0f0) != 0xe0b0)
        break;
       loc_size |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
 
       insn = EXTRACT_INSN (&prologue[vpc + 2]);
       /* ldi r27,<LOCALS_SIZE> / 256 */
       if ((insn & 0xf0f0) != 0xe0b0)
        break;
       loc_size |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;

+      pc_offset += 2;

 
       insn = EXTRACT_INSN (&prologue[vpc + 4]);
       /* ldi r30,pm_lo8(.L_foo_body) */
       if ((insn & 0xf0f0) != 0xe0e0)
        break;
       body_addr = (insn & 0xf) | ((insn & 0x0f00) >> 4);
 
       insn = EXTRACT_INSN (&prologue[vpc + 4]);
       /* ldi r30,pm_lo8(.L_foo_body) */
       if ((insn & 0xf0f0) != 0xe0e0)
        break;
       body_addr = (insn & 0xf) | ((insn & 0x0f00) >> 4);

+      pc_offset += 2;

 
       insn = EXTRACT_INSN (&prologue[vpc + 6]);
       /* ldi r31,pm_hi8(.L_foo_body) */
       if ((insn & 0xf0f0) != 0xe0f0)
        break;
       body_addr |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
 
       insn = EXTRACT_INSN (&prologue[vpc + 6]);
       /* ldi r31,pm_hi8(.L_foo_body) */
       if ((insn & 0xf0f0) != 0xe0f0)
        break;
       body_addr |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;

-
-      if (body_addr != (prologue_start + 10) / 2)
-       break;
+      pc_offset += 2;

 
       msymbol = lookup_minimal_symbol ("__prologue_saves__", NULL, NULL);
       if (!msymbol)
        break;
 
 
       msymbol = lookup_minimal_symbol ("__prologue_saves__", NULL, NULL);
       if (!msymbol)
        break;
 

-      /* FIXME: prologue for mega have a JMP instead of RJMP */

       insn = EXTRACT_INSN (&prologue[vpc + 8]);
       /* rjmp __prologue_saves__+RRR */
       insn = EXTRACT_INSN (&prologue[vpc + 8]);
       /* rjmp __prologue_saves__+RRR */

-      if ((insn & 0xf000) != 0xc000)
-       break;
+      if ((insn & 0xf000) == 0xc000)
+        {
+          /* Extract PC relative offset from RJMP */
+          i = (insn & 0xfff) | (insn & 0x800 ? (-1 ^ 0xfff) : 0);
+          /* Convert offset to byte addressable mode */
+          i *= 2;
+          /* Destination address */
+          i += pc + 10;
+
+          if (body_addr != (pc + 10)/2)
+            break;
+
+          pc_offset += 2;
+        }
+      else if ((insn & 0xfe0e) == 0x940c)
+        {
+          /* Extract absolute PC address from JMP */
+          i = (((insn & 0x1) | ((insn & 0x1f0) >> 3) << 16)
+            | (EXTRACT_INSN (&prologue[vpc + 10]) & 0xffff));
+          /* Convert address to byte addressable mode */
+          i *= 2;
+
+          if (body_addr != (pc + 12)/2)
+            break;
+
+          pc_offset += 4;
+        }
+      else
+        break;

 
 

-      /* Extract PC relative offset from RJMP */
-      i = (insn & 0xfff) | (insn & 0x800 ? (-1 ^ 0xfff) : 0);
-      /* Convert offset to byte addressable mode */
-      i *= 2;
-      /* Destination address */
-      i += vpc + prologue_start + 10;
-      /* Resovle offset (in words) from __prologue_saves__ symbol.
+      /* Resolve offset (in words) from __prologue_saves__ symbol.

          Which is a pushes count in `-mcall-prologues' mode */
       num_pushes = AVR_MAX_PUSHES - (i - SYMBOL_VALUE_ADDRESS (msymbol)) / 2;
 
       if (num_pushes > AVR_MAX_PUSHES)
          Which is a pushes count in `-mcall-prologues' mode */
       num_pushes = AVR_MAX_PUSHES - (i - SYMBOL_VALUE_ADDRESS (msymbol)) / 2;
 
       if (num_pushes > AVR_MAX_PUSHES)

-       num_pushes = 0;
+        {
+          fprintf_unfiltered (gdb_stderr, "Num pushes too large: %d\n",
+                              num_pushes);
+          num_pushes = 0;
+        }

 
       if (num_pushes)
        {
          int from;
 
       if (num_pushes)
        {
          int from;

-         fi->saved_regs[AVR_FP_REGNUM + 1] = num_pushes;
+
+         info->saved_regs[AVR_FP_REGNUM + 1].addr = num_pushes;

          if (num_pushes >= 2)
          if (num_pushes >= 2)

-           fi->saved_regs[AVR_FP_REGNUM] = num_pushes - 1;
+           info->saved_regs[AVR_FP_REGNUM].addr = num_pushes - 1;
+

          i = 0;
          for (from = AVR_LAST_PUSHED_REGNUM + 1 - (num_pushes - 2);
               from <= AVR_LAST_PUSHED_REGNUM; ++from)
          i = 0;
          for (from = AVR_LAST_PUSHED_REGNUM + 1 - (num_pushes - 2);
               from <= AVR_LAST_PUSHED_REGNUM; ++from)

-           fi->saved_regs[from] = ++i;
+           info->saved_regs [from].addr = ++i;

        }
        }

-      fi->extra_info->locals_size = loc_size;
-      fi->extra_info->framesize = loc_size + num_pushes;
-      fi->extra_info->framereg = AVR_FP_REGNUM;
-      return;
+      info->size = loc_size + num_pushes;
+      info->prologue_type = AVR_PROLOGUE_CALL;
+
+      return pc + pc_offset;

     }
 
     }
 

-  /* Scan interrupt or signal function */
+  /* Scan for the beginning of the prologue for an interrupt or signal
+     function.  Note that we have to set the prologue type here since the
+     third stage of the prologue may not be present (e.g. no saved registered
+     or changing of the SP register).  */

 
 

-  if (prologue_len >= 12)
+  if (1)

     {
       unsigned char img[] = {
        0x78, 0x94,             /* sei */
     {
       unsigned char img[] = {
        0x78, 0x94,             /* sei */


@@ -621,44 +629,52 @@ avr_scan_prologue (struct frame_info *fi)
       };
       if (memcmp (prologue, img, sizeof (img)) == 0)
        {
       };
       if (memcmp (prologue, img, sizeof (img)) == 0)
        {

+          info->prologue_type = AVR_PROLOGUE_INTR;

          vpc += sizeof (img);
          vpc += sizeof (img);

-         fi->saved_regs[0] = 2;
-         fi->saved_regs[1] = 1;
-         fi->extra_info->framesize += 3;
+          info->saved_regs[AVR_SREG_REGNUM].addr = 3;
+          info->saved_regs[0].addr = 2;
+          info->saved_regs[1].addr = 1;
+          info->size += 3;

        }
        }

-      else if (memcmp (img + 1, prologue, sizeof (img) - 1) == 0)
+      else if (memcmp (img + 2, prologue, sizeof (img) - 2) == 0)

        {
        {

-         vpc += sizeof (img) - 1;
-         fi->saved_regs[0] = 2;
-         fi->saved_regs[1] = 1;
-         fi->extra_info->framesize += 3;
+          info->prologue_type = AVR_PROLOGUE_SIG;
+          vpc += sizeof (img) - 2;
+          info->saved_regs[AVR_SREG_REGNUM].addr = 3;
+          info->saved_regs[0].addr = 2;
+          info->saved_regs[1].addr = 1;
+          info->size += 3;

        }
     }
 
   /* First stage of the prologue scanning.
        }
     }
 
   /* First stage of the prologue scanning.

-     Scan pushes */
+     Scan pushes (saved registers) */

 
 

-  for (; vpc <= prologue_len; vpc += 2)
+  for (; vpc < AVR_MAX_PROLOGUE_SIZE; vpc += 2)

     {
       insn = EXTRACT_INSN (&prologue[vpc]);
       if ((insn & 0xfe0f) == 0x920f)   /* push rXX */
        {
          /* Bits 4-9 contain a mask for registers R0-R32. */
     {
       insn = EXTRACT_INSN (&prologue[vpc]);
       if ((insn & 0xfe0f) == 0x920f)   /* push rXX */
        {
          /* Bits 4-9 contain a mask for registers R0-R32. */

-         regno = (insn & 0x1f0) >> 4;
-         ++fi->extra_info->framesize;
-         fi->saved_regs[regno] = fi->extra_info->framesize;
+         int regno = (insn & 0x1f0) >> 4;
+         info->size++;
+         info->saved_regs[regno].addr = info->size;

          scan_stage = 1;
        }
       else
        break;
     }
 
          scan_stage = 1;
        }
       else
        break;
     }
 

+  if (vpc >= AVR_MAX_PROLOGUE_SIZE)
+     fprintf_unfiltered (gdb_stderr,
+                         "Hit end of prologue while scanning pushes\n");
+

   /* Second stage of the prologue scanning.
      Scan:
      in r28,__SP_L__
      in r29,__SP_H__ */
 
   /* Second stage of the prologue scanning.
      Scan:
      in r28,__SP_L__
      in r29,__SP_H__ */
 

-  if (scan_stage == 1 && vpc + 4 <= prologue_len)
+  if (scan_stage == 1 && vpc < AVR_MAX_PROLOGUE_SIZE)

     {
       unsigned char img[] = {
        0xcd, 0xb7,             /* in r28,__SP_L__ */
     {
       unsigned char img[] = {
        0xcd, 0xb7,             /* in r28,__SP_L__ */


@@ -669,7 +685,6 @@ avr_scan_prologue (struct frame_info *fi)
       if (memcmp (prologue + vpc, img, sizeof (img)) == 0)
        {
          vpc += 4;
       if (memcmp (prologue + vpc, img, sizeof (img)) == 0)
        {
          vpc += 4;

-         fi->extra_info->framereg = AVR_FP_REGNUM;

          scan_stage = 2;
        }
     }
          scan_stage = 2;
        }
     }


@@ -677,32 +692,32 @@ avr_scan_prologue (struct frame_info *fi)
   /* Third stage of the prologue scanning. (Really two stages)
      Scan for:
      sbiw r28,XX or subi r28,lo8(XX)
   /* Third stage of the prologue scanning. (Really two stages)
      Scan for:
      sbiw r28,XX or subi r28,lo8(XX)

-     sbci r29,hi8(XX)
+                    sbci r29,hi8(XX)

      in __tmp_reg__,__SREG__
      cli
      in __tmp_reg__,__SREG__
      cli

-     out __SP_L__,r28
+     out __SP_H__,r29

      out __SREG__,__tmp_reg__
      out __SREG__,__tmp_reg__

-     out __SP_H__,r29 */
+     out __SP_L__,r28 */

 
 

-  if (scan_stage == 2 && vpc + 12 <= prologue_len)
+  if (scan_stage == 2 && vpc < AVR_MAX_PROLOGUE_SIZE)

     {
       int locals_size = 0;
       unsigned char img[] = {
        0x0f, 0xb6,             /* in r0,0x3f */
        0xf8, 0x94,             /* cli */
     {
       int locals_size = 0;
       unsigned char img[] = {
        0x0f, 0xb6,             /* in r0,0x3f */
        0xf8, 0x94,             /* cli */

-       0xcd, 0xbf,             /* out 0x3d,r28 ; SPL */
+       0xde, 0xbf,             /* out 0x3e,r29 ; SPH */

        0x0f, 0xbe,             /* out 0x3f,r0  ; SREG */
        0x0f, 0xbe,             /* out 0x3f,r0  ; SREG */

-       0xde, 0xbf              /* out 0x3e,r29 ; SPH */
+       0xcd, 0xbf              /* out 0x3d,r28 ; SPL */

       };
       unsigned char img_sig[] = {
       };
       unsigned char img_sig[] = {

-       0xcd, 0xbf,             /* out 0x3d,r28 ; SPL */
-       0xde, 0xbf              /* out 0x3e,r29 ; SPH */
+       0xde, 0xbf,             /* out 0x3e,r29 ; SPH */
+       0xcd, 0xbf              /* out 0x3d,r28 ; SPL */

       };
       unsigned char img_int[] = {
        0xf8, 0x94,             /* cli */
       };
       unsigned char img_int[] = {
        0xf8, 0x94,             /* cli */

-       0xcd, 0xbf,             /* out 0x3d,r28 ; SPL */
+       0xde, 0xbf,             /* out 0x3e,r29 ; SPH */

        0x78, 0x94,             /* sei */
        0x78, 0x94,             /* sei */

-       0xde, 0xbf              /* out 0x3e,r29 ; SPH */
+       0xcd, 0xbf              /* out 0x3d,r28 ; SPL */

       };
 
       insn = EXTRACT_INSN (&prologue[vpc]);
       };
 
       insn = EXTRACT_INSN (&prologue[vpc]);


@@ -717,352 +732,378 @@ avr_scan_prologue (struct frame_info *fi)
          locals_size += ((insn & 0xf) | ((insn & 0xf00) >> 4) << 8);
        }
       else
          locals_size += ((insn & 0xf) | ((insn & 0xf00) >> 4) << 8);
        }
       else

-       return;
-      fi->extra_info->locals_size = locals_size;
-      fi->extra_info->framesize += locals_size;
-    }
-}
+       return pc + vpc;
+
+      /* Scan the last part of the prologue. May not be present for interrupt
+         or signal handler functions, which is why we set the prologue type
+         when we saw the beginning of the prologue previously.  */
+
+      if (memcmp (prologue + vpc, img_sig, sizeof (img_sig)) == 0)
+        {
+          vpc += sizeof (img_sig);
+        }
+      else if (memcmp (prologue + vpc, img_int, sizeof (img_int)) == 0)
+        {
+          vpc += sizeof (img_int);
+        }
+      if (memcmp (prologue + vpc, img, sizeof (img)) == 0)
+        {
+          info->prologue_type = AVR_PROLOGUE_NORMAL;
+          vpc += sizeof (img);
+        }

 
 

-/* This function actually figures out the frame address for a given pc and
-   sp.  This is tricky  because we sometimes don't use an explicit
-   frame pointer, and the previous stack pointer isn't necessarily recorded
-   on the stack.  The only reliable way to get this info is to
-   examine the prologue.  */
+      info->size += locals_size;

 
 

-static void
-avr_init_extra_frame_info (int fromleaf, struct frame_info *fi)
-{
-  int reg;
+      return pc + avr_scan_arg_moves (vpc, prologue);
+    }

 
 

-  if (fi->next)
-    fi->pc = FRAME_SAVED_PC (fi->next);
+  /* If we got this far, we could not scan the prologue, so just return the pc
+     of the frame plus an adjustment for argument move insns.  */

 
 

-  fi->extra_info = (struct frame_extra_info *)
-    frame_obstack_alloc (sizeof (struct frame_extra_info));
-  frame_saved_regs_zalloc (fi);
+  return pc + avr_scan_arg_moves (vpc, prologue);;
+}

 
 

-  fi->extra_info->return_pc = 0;
-  fi->extra_info->args_pointer = 0;
-  fi->extra_info->locals_size = 0;
-  fi->extra_info->framereg = 0;
-  fi->extra_info->framesize = 0;
-  fi->extra_info->is_main = 0;
+static CORE_ADDR
+avr_skip_prologue (CORE_ADDR pc)
+{
+  CORE_ADDR func_addr, func_end;
+  CORE_ADDR prologue_end = pc;

 
 

-  avr_scan_prologue (fi);
+  /* See what the symbol table says */

 
 

-  if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
-    {
-      /* We need to setup fi->frame here because run_stack_dummy gets it wrong
-         by assuming it's always FP.  */
-      fi->frame = deprecated_read_register_dummy (fi->pc, fi->frame,
-                                                 AVR_PC_REGNUM);
-    }
-  else if (!fi->next)          /* this is the innermost frame? */
-    fi->frame = read_register (fi->extra_info->framereg);
-  else if (fi->extra_info->is_main != 1)       /* not the innermost frame, not `main' */
-    /* If we have an next frame,  the callee saved it. */
+  if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))

     {
     {

-      struct frame_info *next_fi = fi->next;
-      if (fi->extra_info->framereg == AVR_SP_REGNUM)
-       fi->frame =
-         next_fi->frame + 2 /* ret addr */  + next_fi->extra_info->framesize;
-      /* FIXME: I don't analyse va_args functions  */
-      else
-       {
-         CORE_ADDR fp = 0;
-         CORE_ADDR fp1 = 0;
-         unsigned int fp_low, fp_high;
+      struct symtab_and_line sal;
+      struct avr_unwind_cache info = {0};
+      struct trad_frame_saved_reg saved_regs[AVR_NUM_REGS];

 
 

-         /* Scan all frames */
-         for (; next_fi; next_fi = next_fi->next)
-           {
-             /* look for saved AVR_FP_REGNUM */
-             if (next_fi->saved_regs[AVR_FP_REGNUM] && !fp)
-               fp = next_fi->saved_regs[AVR_FP_REGNUM];
-             /* look for saved AVR_FP_REGNUM + 1 */
-             if (next_fi->saved_regs[AVR_FP_REGNUM + 1] && !fp1)
-               fp1 = next_fi->saved_regs[AVR_FP_REGNUM + 1];
-           }
-         fp_low = (fp ? read_memory_unsigned_integer (avr_make_saddr (fp), 1)
-                   : read_register (AVR_FP_REGNUM)) & 0xff;
-         fp_high =
-           (fp1 ? read_memory_unsigned_integer (avr_make_saddr (fp1), 1) :
-            read_register (AVR_FP_REGNUM + 1)) & 0xff;
-         fi->frame = fp_low | (fp_high << 8);
-       }
-    }
+      info.saved_regs = saved_regs;

 
 

-  /* TRoth: Do we want to do this if we are in main? I don't think we should
-     since return_pc makes no sense when we are in main. */
+      /* Need to run the prologue scanner to figure out if the function has a
+         prologue and possibly skip over moving arguments passed via registers
+         to other registers.  */

 
 

-  if ((fi->pc) && (fi->extra_info->is_main == 0))      /* We are not in CALL_DUMMY */
-    {
-      CORE_ADDR addr;
-      int i;
+      prologue_end = avr_scan_prologue (pc, &info);

 
 

-      addr = fi->frame + fi->extra_info->framesize + 1;
+      if (info.prologue_type == AVR_PROLOGUE_NONE)
+        return pc;
+      else
+        {
+          sal = find_pc_line (func_addr, 0);

 
 

-      /* Return address in stack in different endianness */
+          if (sal.line != 0 && sal.end < func_end)
+            return sal.end;
+        }
+    }

 
 

-      fi->extra_info->return_pc =
-       read_memory_unsigned_integer (avr_make_saddr (addr), 1) << 8;
-      fi->extra_info->return_pc |=
-       read_memory_unsigned_integer (avr_make_saddr (addr + 1), 1);
+/* Either we didn't find the start of this function (nothing we can do),
+   or there's no line info, or the line after the prologue is after
+   the end of the function (there probably isn't a prologue). */

 
 

-      /* This return address in words,
-         must be converted to the bytes address */
-      fi->extra_info->return_pc *= 2;
+  return prologue_end;
+}

 
 

-      /* Resolve a pushed registers addresses */
-      for (i = 0; i < NUM_REGS; i++)
-       {
-         if (fi->saved_regs[i])
-           fi->saved_regs[i] = addr - fi->saved_regs[i];
-       }
-    }
+/* Not all avr devices support the BREAK insn. Those that don't should treat
+   it as a NOP. Thus, it should be ok. Since the avr is currently a remote
+   only target, this shouldn't be a problem (I hope). TRoth/2003-05-14  */
+
+static const unsigned char *
+avr_breakpoint_from_pc (CORE_ADDR * pcptr, int *lenptr)
+{
+    static unsigned char avr_break_insn [] = { 0x98, 0x95 };
+    *lenptr = sizeof (avr_break_insn);
+    return avr_break_insn;

 }
 
 }
 

-/* Restore the machine to the state it had before the current frame was
-   created.  Usually used either by the "RETURN" command, or by
-   call_function_by_hand after the dummy_frame is finished. */
+/* Given a return value in `regbuf' with a type `valtype', 
+   extract and copy its value into `valbuf'.
+
+   Return values are always passed via registers r25:r24:...  */

 
 static void
 
 static void

-avr_pop_frame (void)
+avr_extract_return_value (struct type *type, struct regcache *regcache,
+                          void *valbuf)

 {
 {

-  unsigned regnum;
-  CORE_ADDR saddr;
-  struct frame_info *frame = get_current_frame ();
-
-  if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
+  ULONGEST r24, r25;
+  ULONGEST c;
+  int len;
+  if (TYPE_LENGTH (type) == 1)

     {
     {

-      generic_pop_dummy_frame ();
+      regcache_cooked_read_unsigned (regcache, 24, &c);
+      store_unsigned_integer (valbuf, 1, c);

     }
   else
     {
     }
   else
     {

-      /* TRoth: Why only loop over 8 registers? */
-
-      for (regnum = 0; regnum < 8; regnum++)
-       {
-         /* Don't forget AVR_SP_REGNUM in a frame_saved_regs struct is the
-            actual value we want, not the address of the value we want.  */
-         if (frame->saved_regs[regnum] && regnum != AVR_SP_REGNUM)
-           {
-             saddr = avr_make_saddr (frame->saved_regs[regnum]);
-             write_register (regnum,
-                             read_memory_unsigned_integer (saddr, 1));
-           }
-         else if (frame->saved_regs[regnum] && regnum == AVR_SP_REGNUM)
-           write_register (regnum, frame->frame + 2);
-       }
-
-      /* Don't forget the update the PC too!  */
-      write_pc (frame->extra_info->return_pc);
+      int i;
+      /* The MSB of the return value is always in r25, calculate which
+         register holds the LSB.  */
+      int lsb_reg = 25 - TYPE_LENGTH (type) + 1;
+
+      for (i=0; i< TYPE_LENGTH (type); i++)
+        {
+          regcache_cooked_read (regcache, lsb_reg + i,
+                                (bfd_byte *) valbuf + i);
+        }

     }
     }

-  flush_cached_frames ();

 }
 
 }
 

-/* Return the saved PC from this frame. */
+/* Put here the code to store, into fi->saved_regs, the addresses of
+   the saved registers of frame described by FRAME_INFO.  This
+   includes special registers such as pc and fp saved in special ways
+   in the stack frame.  sp is even more special: the address we return
+   for it IS the sp for the next frame. */

 
 

-static CORE_ADDR
-avr_frame_saved_pc (struct frame_info *frame)
+struct avr_unwind_cache *
+avr_frame_unwind_cache (struct frame_info *next_frame,
+                        void **this_prologue_cache)

 {
 {

-  if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
-    return deprecated_read_register_dummy (frame->pc, frame->frame,
-                                          AVR_PC_REGNUM);
-  else
-    return frame->extra_info->return_pc;
-}
+  CORE_ADDR pc;
+  ULONGEST prev_sp;
+  ULONGEST this_base;
+  struct avr_unwind_cache *info;
+  int i;

 
 

-static CORE_ADDR
-avr_saved_pc_after_call (struct frame_info *frame)
-{
-  unsigned char m1, m2;
-  unsigned int sp = read_register (AVR_SP_REGNUM);
-  m1 = read_memory_unsigned_integer (avr_make_saddr (sp + 1), 1);
-  m2 = read_memory_unsigned_integer (avr_make_saddr (sp + 2), 1);
-  return (m2 | (m1 << 8)) * 2;
-}
+  if ((*this_prologue_cache))
+    return (*this_prologue_cache);

 
 

-/* Figure out where in REGBUF the called function has left its return value.
-   Copy that into VALBUF. */
+  info = FRAME_OBSTACK_ZALLOC (struct avr_unwind_cache);
+  (*this_prologue_cache) = info;
+  info->saved_regs = trad_frame_alloc_saved_regs (next_frame);

 
 

-static void
-avr_extract_return_value (struct type *type, char *regbuf, char *valbuf)
-{
-  int wordsize, len;
+  info->size = 0;
+  info->prologue_type = AVR_PROLOGUE_NONE;

 
 

-  wordsize = 2;
+  pc = frame_func_unwind (next_frame);

 
 

-  len = TYPE_LENGTH (type);
+  if ((pc > 0) && (pc < frame_pc_unwind (next_frame)))
+    avr_scan_prologue (pc, info);

 
 

-  switch (len)
+  if ((info->prologue_type != AVR_PROLOGUE_NONE)
+      && (info->prologue_type != AVR_PROLOGUE_MAIN))

     {
     {

-    case 1:                    /* (char) */
-    case 2:                    /* (short), (int) */
-      memcpy (valbuf, regbuf + REGISTER_BYTE (24), 2);
-      break;
-    case 4:                    /* (long), (float) */
-      memcpy (valbuf, regbuf + REGISTER_BYTE (22), 4);
-      break;
-    case 8:                    /* (double) (doesn't seem to happen, which is good,
-                                  because this almost certainly isn't right.  */
-      error ("I don't know how a double is returned.");
-      break;
+      ULONGEST high_base;       /* High byte of FP */
+
+      /* 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, AVR_FP_REGNUM, &this_base);
+      frame_unwind_unsigned_register (next_frame, AVR_FP_REGNUM+1, &high_base);
+      this_base += (high_base << 8);
+      
+      /* 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; 
+   }
+  else
+    {
+      /* Assume that the FP is this frame's SP but with that pushed
+         stack space added back.  */
+      frame_unwind_unsigned_register (next_frame, AVR_SP_REGNUM, &this_base);
+      prev_sp = this_base + info->size;

     }
     }

-}

 
 

-/* Returns the return address for a dummy. */
+  /* Add 1 here to adjust for the post-decrement nature of the push
+     instruction.*/
+  info->prev_sp = avr_make_saddr (prev_sp+1);

 
 

-static CORE_ADDR
-avr_call_dummy_address (void)
-{
-  return entry_point_address ();
-}
+  info->base = avr_make_saddr (this_base);

 
 

-/* Place the appropriate value in the appropriate registers.
-   Primarily used by the RETURN command.  */
+  /* 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)
+      {
+        info->saved_regs[i].addr = (info->prev_sp - info->saved_regs[i].addr);
+      }

 
 

-static void
-avr_store_return_value (struct type *type, char *valbuf)
-{
-  int wordsize, len, regval;
-
-  wordsize = 2;
+  /* Except for the main and startup code, the return PC is always saved on
+     the stack and is at the base of the frame. */

 
 

-  len = TYPE_LENGTH (type);
-  switch (len)
+  if (info->prologue_type != AVR_PROLOGUE_MAIN)

     {
     {

-    case 1:                    /* char */
-    case 2:                    /* short, int */
-      regval = extract_address (valbuf, len);
-      write_register (0, regval);
-      break;
-    case 4:                    /* long, float */
-      regval = extract_address (valbuf, len);
-      write_register (0, regval >> 16);
-      write_register (1, regval & 0xffff);
-      break;
-    case 8:                    /* presumeably double, but doesn't seem to happen */
-      error ("I don't know how to return a double.");
-      break;
-    }
-}
+      info->saved_regs[AVR_PC_REGNUM].addr = info->prev_sp;
+    }  

 
 

-/* Setup the return address for a dummy frame, as called by
-   call_function_by_hand.  Only necessary when you are using an empty
-   CALL_DUMMY. */
+  /* The previous frame's SP needed to be computed.  Save the computed
+     value.  */
+  trad_frame_set_value (info->saved_regs, AVR_SP_REGNUM, info->prev_sp+1);
+
+  return info;
+}

 
 static CORE_ADDR
 
 static CORE_ADDR

-avr_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
+avr_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)

 {
 {

-  unsigned char buf[2];
-  int wordsize = 2;
-#if 0
-  struct minimal_symbol *msymbol;
-  CORE_ADDR mon_brk;
-#endif
+  ULONGEST pc;

 
 

-  buf[0] = 0;
-  buf[1] = 0;
-  sp -= wordsize;
-  write_memory (sp + 1, buf, 2);
+  frame_unwind_unsigned_register (next_frame, AVR_PC_REGNUM, &pc);

 
 

-#if 0
-  /* FIXME: TRoth/2002-02-18: This should probably be removed since it's a
-     left-over from Denis' original patch which used avr-mon for the target
-     instead of the generic remote target. */
-  if ((strcmp (target_shortname, "avr-mon") == 0)
-      && (msymbol = lookup_minimal_symbol ("gdb_break", NULL, NULL)))
-    {
-      mon_brk = SYMBOL_VALUE_ADDRESS (msymbol);
-      store_unsigned_integer (buf, wordsize, mon_brk / 2);
-      sp -= wordsize;
-      write_memory (sp + 1, buf + 1, 1);
-      write_memory (sp + 2, buf, 1);
-    }
-#endif
-  return sp;
+  return avr_make_iaddr (pc);

 }
 
 }
 

-static CORE_ADDR
-avr_skip_prologue (CORE_ADDR pc)
+/* Given a GDB frame, determine the address of the calling function's
+   frame.  This will be used to create a new GDB frame struct.  */
+
+static void
+avr_frame_this_id (struct frame_info *next_frame,
+                   void **this_prologue_cache,
+                   struct frame_id *this_id)

 {
 {

-  CORE_ADDR func_addr, func_end;
-  struct symtab_and_line sal;
+  struct avr_unwind_cache *info
+    = avr_frame_unwind_cache (next_frame, this_prologue_cache);
+  CORE_ADDR base;
+  CORE_ADDR func;
+  struct frame_id id;
+
+  /* The FUNC is easy.  */
+  func = frame_func_unwind (next_frame);
+
+  /* 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->prev_sp;
+  if (base == 0)
+    return;
+
+  id = frame_id_build (base, func);
+  (*this_id) = id;
+}

 
 

-  /* See what the symbol table says */
+static void
+avr_frame_prev_register (struct frame_info *next_frame,
+                         void **this_prologue_cache,
+                         int regnum, int *optimizedp,
+                         enum lval_type *lvalp, CORE_ADDR *addrp,
+                         int *realnump, void *bufferp)
+{
+  struct avr_unwind_cache *info
+    = avr_frame_unwind_cache (next_frame, this_prologue_cache);

 
 

-  if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+  if (regnum == AVR_PC_REGNUM)

     {
     {

-      sal = find_pc_line (func_addr, 0);
-
-      /* troth/2002-08-05: For some very simple functions, gcc doesn't
-         generate a prologue and the sal.end ends up being the 2-byte ``ret''
-         instruction at the end of the function, but func_end ends up being
-         the address of the first instruction of the _next_ function. By
-         adjusting func_end by 2 bytes, we can catch these functions and not
-         return sal.end if it is the ``ret'' instruction. */
-
-      if (sal.line != 0 && sal.end < (func_end-2))
-       return sal.end;
+      if (trad_frame_addr_p (info->saved_regs, regnum))
+        {
+          *optimizedp = 0;
+          *lvalp = lval_memory;
+          *addrp = info->saved_regs[regnum].addr;
+          *realnump = -1;
+          if (bufferp != NULL)
+            {
+              /* Reading the return PC from the PC register is slightly
+                 abnormal.  register_size(AVR_PC_REGNUM) says it is 4 bytes,
+                 but in reality, only two bytes (3 in upcoming mega256) are
+                 stored on the stack.
+
+                 Also, note that the value on the stack is an addr to a word
+                 not a byte, so we will need to multiply it by two at some
+                 point. 
+
+                 And to confuse matters even more, the return address stored
+                 on the stack is in big endian byte order, even though most
+                 everything else about the avr is little endian. Ick!  */
+
+              /* FIXME: number of bytes read here will need updated for the
+                 mega256 when it is available.  */
+
+              ULONGEST pc;
+              unsigned char tmp;
+              unsigned char buf[2];
+
+              read_memory (info->saved_regs[regnum].addr, buf, 2);
+
+              /* Convert the PC read from memory as a big-endian to
+                 little-endian order. */
+              tmp = buf[0];
+              buf[0] = buf[1];
+              buf[1] = tmp;
+
+              pc = (extract_unsigned_integer (buf, 2) * 2);
+              store_unsigned_integer (bufferp,
+                                      register_size (current_gdbarch, regnum),
+                                      pc);
+            }
+        }

     }
     }

+  else
+    trad_frame_prev_register (next_frame, info->saved_regs, regnum,
+                              optimizedp, lvalp, addrp, realnump, bufferp);
+}

 
 

-/* Either we didn't find the start of this function (nothing we can do),
-   or there's no line info, or the line after the prologue is after
-   the end of the function (there probably isn't a prologue). */
+static const struct frame_unwind avr_frame_unwind = {
+  NORMAL_FRAME,
+  avr_frame_this_id,
+  avr_frame_prev_register
+};

 
 

-  return pc;
+const struct frame_unwind *
+avr_frame_sniffer (struct frame_info *next_frame)
+{
+  return &avr_frame_unwind;

 }
 
 static CORE_ADDR
 }
 
 static CORE_ADDR

-avr_frame_address (struct frame_info *fi)
+avr_frame_base_address (struct frame_info *next_frame, void **this_cache)

 {
 {

-  return avr_make_saddr (fi->frame);
+  struct avr_unwind_cache *info
+    = avr_frame_unwind_cache (next_frame, this_cache);
+
+  return info->base;

 }
 
 }
 

-/* Given a GDB frame, determine the address of the calling function's frame.
-   This will be used to create a new GDB frame struct, and then
-   INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
+static const struct frame_base avr_frame_base = {
+  &avr_frame_unwind,
+  avr_frame_base_address,
+  avr_frame_base_address,
+  avr_frame_base_address
+};

 
 

-   For us, the frame address is its stack pointer value, so we look up
-   the function prologue to determine the caller's sp value, and return it.  */
+/* Assuming NEXT_FRAME->prev is a dummy, return the frame ID of that
+   dummy frame.  The frame ID's base needs to match the TOS value
+   saved by save_dummy_frame_tos(), and the PC match the dummy frame's
+   breakpoint.  */

 
 

-static CORE_ADDR
-avr_frame_chain (struct frame_info *frame)
+static struct frame_id
+avr_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)

 {
 {

-  if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
-    {
-      /* initialize the return_pc now */
-      frame->extra_info->return_pc
-       = deprecated_read_register_dummy (frame->pc, frame->frame,
-                                         AVR_PC_REGNUM);
-      return frame->frame;
-    }
-  return (frame->extra_info->is_main ? 0
-         : frame->frame + frame->extra_info->framesize + 2 /* ret addr */ );
+  ULONGEST base;
+
+  frame_unwind_unsigned_register (next_frame, AVR_SP_REGNUM, &base);
+  return frame_id_build (avr_make_saddr (base), frame_pc_unwind (next_frame));

 }
 
 }
 

-/* Store the address of the place in which to copy the structure the
-   subroutine will return.  This is called from call_function. 
+/* When arguments must be pushed onto the stack, they go on in reverse
+   order.  The below implements a FILO (stack) to do this. */

 
 

-   We store structs through a pointer passed in the first Argument
-   register. */
+struct stack_item
+{
+  int len;
+  struct stack_item *prev;
+  void *data;
+};

 
 

-static void
-avr_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
+static struct stack_item *push_stack_item (struct stack_item *prev,
+                                          void *contents, int len);
+static struct stack_item *
+push_stack_item (struct stack_item *prev, void *contents, int len)

 {
 {

-  write_register (0, addr);
+  struct stack_item *si;
+  si = xmalloc (sizeof (struct stack_item));
+  si->data = xmalloc (len);
+  si->len = len;
+  si->prev = prev;
+  memcpy (si->data, contents, len);
+  return si;

 }
 
 }
 

-/* Extract from an array REGBUF containing the (raw) register state
-   the address in which a function should return its structure value,
-   as a CORE_ADDR (or an expression that can be used as one). */
-
-static CORE_ADDR
-avr_extract_struct_value_address (char *regbuf)
+static struct stack_item *pop_stack_item (struct stack_item *si);
+static struct stack_item *
+pop_stack_item (struct stack_item *si)

 {
 {

-  return (extract_address ((regbuf) + REGISTER_BYTE (0),
-                          REGISTER_RAW_SIZE (0)) | AVR_SMEM_START);
+  struct stack_item *dead = si;
+  si = si->prev;
+  xfree (dead->data);
+  xfree (dead);
+  return si;

 }
 
 /* Setup the function arguments for calling a function in the inferior.
 }
 
 /* Setup the function arguments for calling a function in the inferior.


@@ -1071,9 +1112,20 @@ avr_extract_struct_value_address (char *regbuf)
    dedicated for passing function arguments.  Up to the first 18 arguments
    (depending on size) may go into these registers.  The rest go on the stack.
 
    dedicated for passing function arguments.  Up to the first 18 arguments
    (depending on size) may go into these registers.  The rest go on the stack.
 

-   Arguments that are larger than WORDSIZE bytes will be split between two or
-   more registers as available, but will NOT be split between a register and
-   the stack.
+   All arguments are aligned to start in even-numbered registers (odd-sized
+   arguments, including char, have one free register above them). For example,
+   an int in arg1 and a char in arg2 would be passed as such:
+
+      arg1 -> r25:r24
+      arg2 -> r22
+
+   Arguments that are larger than 2 bytes will be split between two or more
+   registers as available, but will NOT be split between a register and the
+   stack. Arguments that go onto the stack are pushed last arg first (this is
+   similar to the d10v).  */
+
+/* NOTE: TRoth/2003-06-17: The rest of this comment is old looks to be
+   inaccurate.

 
    An exceptional case exists for struct arguments (and possibly other
    aggregates such as arrays) -- if the size is larger than WORDSIZE bytes but
 
    An exceptional case exists for struct arguments (and possibly other
    aggregates such as arrays) -- if the size is larger than WORDSIZE bytes but


@@ -1094,52 +1146,86 @@ avr_extract_struct_value_address (char *regbuf)
    registers R0 to R2. */
 
 static CORE_ADDR
    registers R0 to R2. */
 
 static CORE_ADDR

-avr_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
-                   int struct_return, CORE_ADDR struct_addr)
+avr_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
+                     struct regcache *regcache, CORE_ADDR bp_addr,
+                     int nargs, struct value **args, CORE_ADDR sp,
+                     int struct_return, CORE_ADDR struct_addr)

 {
 {

-  int stack_alloc, stack_offset;
-  int wordsize;
-  int argreg;
-  int argnum;
-  struct type *type;
-  CORE_ADDR regval;
-  char *val;
-  char valbuf[4];
-  int len;
+  int i;
+  unsigned char buf[2];
+  CORE_ADDR return_pc = avr_convert_iaddr_to_raw (bp_addr);
+  int regnum = AVR_ARGN_REGNUM;
+  struct stack_item *si = NULL;

 
 

-  wordsize = 1;

 #if 0
 #if 0

-  /* Now make sure there's space on the stack */
-  for (argnum = 0, stack_alloc = 0; argnum < nargs; argnum++)
-    stack_alloc += TYPE_LENGTH (VALUE_TYPE (args[argnum]));
-  sp -= stack_alloc;           /* make room on stack for args */
-  /* we may over-allocate a little here, but that won't hurt anything */
-#endif
-  argreg = 25;
-  if (struct_return)           /* "struct return" pointer takes up one argreg */
+  /* FIXME: TRoth/2003-06-18: Not sure what to do when returning a struct. */
+  if (struct_return)

     {
     {

-      write_register (--argreg, struct_addr);
+      fprintf_unfiltered (gdb_stderr, "struct_return: 0x%lx\n", struct_addr);
+      write_register (argreg--, struct_addr & 0xff);
+      write_register (argreg--, (struct_addr >>8) & 0xff);

     }
     }

+#endif

 
 

-  /* Now load as many as possible of the first arguments into registers, and
-     push the rest onto the stack.  There are 3N bytes in three registers
-     available.  Loop thru args from first to last.  */
+  for (i = 0; i < nargs; i++)
+    {
+      int last_regnum;
+      int j;
+      struct value *arg = args[i];
+      struct type *type = check_typedef (VALUE_TYPE (arg));
+      char *contents = VALUE_CONTENTS (arg);
+      int len = TYPE_LENGTH (type);
+
+      /* Calculate the potential last register needed. */
+      last_regnum = regnum - (len + (len & 1));
+
+      /* If there are registers available, use them. Once we start putting
+         stuff on the stack, all subsequent args go on stack. */
+      if ((si == NULL) && (last_regnum >= 8))
+        {
+          ULONGEST val;
+
+          /* Skip a register for odd length args. */
+          if (len & 1)
+            regnum--;
+
+          val = extract_unsigned_integer (contents, len);
+          for (j=0; j<len; j++)
+            {
+              regcache_cooked_write_unsigned (regcache, regnum--,
+                                              val >> (8*(len-j-1)));
+            }
+        }
+      /* No registers available, push the args onto the stack. */
+      else
+        {
+          /* From here on, we don't care about regnum. */
+          si = push_stack_item (si, contents, len);
+        }
+    }

 
 

-  for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++)
+  /* Push args onto the stack. */
+  while (si)

     {
     {

-      type = VALUE_TYPE (args[argnum]);
-      len = TYPE_LENGTH (type);
-      val = (char *) VALUE_CONTENTS (args[argnum]);
-
-      /* NOTE WELL!!!!!  This is not an "else if" clause!!!  That's because
-         some *&^%$ things get passed on the stack AND in the registers!  */
-      while (len > 0)
-       {                       /* there's room in registers */
-         len -= wordsize;
-         regval = extract_address (val + len, wordsize);
-         write_register (argreg--, regval);
-       }
+      sp -= si->len;
+      /* Add 1 to sp here to account for post decr nature of pushes. */
+      write_memory (sp+1, si->data, si->len);
+      si = pop_stack_item (si);

     }
     }

+
+  /* Set the return address.  For the avr, the return address is the BP_ADDR.
+     Need to push the return address onto the stack noting that it needs to be
+     in big-endian order on the stack.  */
+  buf[0] = (return_pc >> 8) & 0xff;
+  buf[1] = return_pc & 0xff;
+
+  sp -= 2;
+  write_memory (sp+1, buf, 2);  /* Add one since pushes are post decr ops. */
+
+  /* Finally, update the SP register. */
+  regcache_cooked_write_unsigned (regcache, AVR_SP_REGNUM,
+                                 avr_convert_saddr_to_raw (sp));
+

   return sp;
 }
 
   return sp;
 }
 


@@ -1148,12 +1234,6 @@ avr_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
 static struct gdbarch *
 avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 {
 static struct gdbarch *
 avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 {

-  /* FIXME: TRoth/2002-02-18: I have no idea if avr_call_dummy_words[] should
-     be bigger or not. Initial testing seems to show that `call my_func()`
-     works and backtrace from a breakpoint within the call looks correct.
-     Admittedly, I haven't tested with more than a very simple program. */
-  static LONGEST avr_call_dummy_words[] = { 0 };
-

   struct gdbarch *gdbarch;
   struct gdbarch_tdep *tdep;
 
   struct gdbarch *gdbarch;
   struct gdbarch_tdep *tdep;
 


@@ -1183,7 +1263,6 @@ avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
   set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
   set_gdbarch_addr_bit (gdbarch, 32);
   set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
   set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
   set_gdbarch_addr_bit (gdbarch, 32);

-  set_gdbarch_bfd_vma_bit (gdbarch, 32);       /* FIXME: TRoth/2002-02-18: Is this needed? */

 
   set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
   set_gdbarch_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
 
   set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
   set_gdbarch_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);


@@ -1195,78 +1274,39 @@ avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 
   set_gdbarch_read_pc (gdbarch, avr_read_pc);
   set_gdbarch_write_pc (gdbarch, avr_write_pc);
 
   set_gdbarch_read_pc (gdbarch, avr_read_pc);
   set_gdbarch_write_pc (gdbarch, avr_write_pc);

-  set_gdbarch_read_fp (gdbarch, avr_read_fp);

   set_gdbarch_read_sp (gdbarch, avr_read_sp);
   set_gdbarch_read_sp (gdbarch, avr_read_sp);

-  set_gdbarch_write_sp (gdbarch, avr_write_sp);

 
   set_gdbarch_num_regs (gdbarch, AVR_NUM_REGS);
 
   set_gdbarch_sp_regnum (gdbarch, AVR_SP_REGNUM);
 
   set_gdbarch_num_regs (gdbarch, AVR_NUM_REGS);
 
   set_gdbarch_sp_regnum (gdbarch, AVR_SP_REGNUM);

-  set_gdbarch_fp_regnum (gdbarch, AVR_FP_REGNUM);

   set_gdbarch_pc_regnum (gdbarch, AVR_PC_REGNUM);
 
   set_gdbarch_register_name (gdbarch, avr_register_name);
   set_gdbarch_pc_regnum (gdbarch, AVR_PC_REGNUM);
 
   set_gdbarch_register_name (gdbarch, avr_register_name);

-  set_gdbarch_register_size (gdbarch, 1);
-  set_gdbarch_register_bytes (gdbarch, AVR_NUM_REG_BYTES);
-  set_gdbarch_register_byte (gdbarch, avr_register_byte);
-  set_gdbarch_register_raw_size (gdbarch, avr_register_raw_size);
-  set_gdbarch_max_register_raw_size (gdbarch, 4);
-  set_gdbarch_register_virtual_size (gdbarch, avr_register_virtual_size);
-  set_gdbarch_max_register_virtual_size (gdbarch, 4);
-  set_gdbarch_register_virtual_type (gdbarch, avr_register_virtual_type);
+  set_gdbarch_register_type (gdbarch, avr_register_type);

 
 

+  set_gdbarch_extract_return_value (gdbarch, avr_extract_return_value);

   set_gdbarch_print_insn (gdbarch, print_insn_avr);
 
   set_gdbarch_print_insn (gdbarch, print_insn_avr);
 

-  set_gdbarch_call_dummy_address (gdbarch, avr_call_dummy_address);
-  set_gdbarch_call_dummy_start_offset (gdbarch, 0);
-  set_gdbarch_call_dummy_breakpoint_offset_p (gdbarch, 1);
-  set_gdbarch_call_dummy_breakpoint_offset (gdbarch, 0);
-  set_gdbarch_call_dummy_length (gdbarch, 0);
-  set_gdbarch_call_dummy_p (gdbarch, 1);
-  set_gdbarch_call_dummy_words (gdbarch, avr_call_dummy_words);
-  set_gdbarch_call_dummy_stack_adjust_p (gdbarch, 0);
-  set_gdbarch_fix_call_dummy (gdbarch, generic_fix_call_dummy);
-
-/*    set_gdbarch_believe_pcc_promotion (gdbarch, 1); // TRoth: should this be set? */
+  set_gdbarch_push_dummy_call (gdbarch, avr_push_dummy_call);

 
   set_gdbarch_address_to_pointer (gdbarch, avr_address_to_pointer);
   set_gdbarch_pointer_to_address (gdbarch, avr_pointer_to_address);
 
   set_gdbarch_address_to_pointer (gdbarch, avr_address_to_pointer);
   set_gdbarch_pointer_to_address (gdbarch, avr_pointer_to_address);

-  set_gdbarch_deprecated_extract_return_value (gdbarch, avr_extract_return_value);
-  set_gdbarch_push_arguments (gdbarch, avr_push_arguments);
-  set_gdbarch_push_dummy_frame (gdbarch, generic_push_dummy_frame);
-  set_gdbarch_push_return_address (gdbarch, avr_push_return_address);
-  set_gdbarch_pop_frame (gdbarch, avr_pop_frame);
-
-  set_gdbarch_deprecated_store_return_value (gdbarch, avr_store_return_value);

 
   set_gdbarch_use_struct_convention (gdbarch, generic_use_struct_convention);
 
   set_gdbarch_use_struct_convention (gdbarch, generic_use_struct_convention);

-  set_gdbarch_store_struct_return (gdbarch, avr_store_struct_return);
-  set_gdbarch_deprecated_extract_struct_value_address
-    (gdbarch, avr_extract_struct_value_address);

 
 

-  set_gdbarch_frame_init_saved_regs (gdbarch, avr_scan_prologue);
-  set_gdbarch_init_extra_frame_info (gdbarch, avr_init_extra_frame_info);

   set_gdbarch_skip_prologue (gdbarch, avr_skip_prologue);
   set_gdbarch_skip_prologue (gdbarch, avr_skip_prologue);

-/*    set_gdbarch_prologue_frameless_p (gdbarch, avr_prologue_frameless_p); */

   set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
 
   set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
 

-  set_gdbarch_decr_pc_after_break (gdbarch, 0);
+  set_gdbarch_breakpoint_from_pc (gdbarch, avr_breakpoint_from_pc);

 
 

-  set_gdbarch_function_start_offset (gdbarch, 0);
-  set_gdbarch_remote_translate_xfer_address (gdbarch,
-                                            avr_remote_translate_xfer_address);
-  set_gdbarch_frame_args_skip (gdbarch, 0);
-  set_gdbarch_frameless_function_invocation (gdbarch, frameless_look_for_prologue);    /* ??? */
-  set_gdbarch_frame_chain (gdbarch, avr_frame_chain);
-  set_gdbarch_frame_chain_valid (gdbarch, generic_func_frame_chain_valid);
-  set_gdbarch_frame_saved_pc (gdbarch, avr_frame_saved_pc);
-  set_gdbarch_frame_args_address (gdbarch, avr_frame_address);
-  set_gdbarch_frame_locals_address (gdbarch, avr_frame_address);
-  set_gdbarch_saved_pc_after_call (gdbarch, avr_saved_pc_after_call);
-  set_gdbarch_frame_num_args (gdbarch, frame_num_args_unknown);
+  set_gdbarch_deprecated_frameless_function_invocation (gdbarch, legacy_frameless_look_for_prologue);

 
 

-  set_gdbarch_convert_from_func_ptr_addr (gdbarch,
-                                         avr_convert_from_func_ptr_addr);
+  frame_unwind_append_sniffer (gdbarch, avr_frame_sniffer);
+  frame_base_set_default (gdbarch, &avr_frame_base);
+
+  set_gdbarch_unwind_dummy_id (gdbarch, avr_unwind_dummy_id);
+
+  set_gdbarch_unwind_pc (gdbarch, avr_unwind_pc);

 
   return gdbarch;
 }
 
   return gdbarch;
 }


@@ -1287,7 +1327,7 @@ avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 static void
 avr_io_reg_read_command (char *args, int from_tty)
 {
 static void
 avr_io_reg_read_command (char *args, int from_tty)
 {

-  int bufsiz = 0;
+  LONGEST bufsiz = 0;

   char buf[400];
   char query[400];
   char *p;
   char buf[400];
   char query[400];
   char *p;


@@ -1295,24 +1335,23 @@ avr_io_reg_read_command (char *args, int from_tty)
   unsigned int val;
   int i, j, k, step;
 
   unsigned int val;
   int i, j, k, step;
 

-/*    fprintf_unfiltered (gdb_stderr, "DEBUG: avr_io_reg_read_command (\"%s\", %d)\n", */
-/*             args, from_tty); */
-
-  if (!current_target.to_query)
+  /* Just get the maximum buffer size. */
+  bufsiz = target_read_partial (&current_target, TARGET_OBJECT_AVR,
+                               NULL, NULL, 0, 0);
+  if (bufsiz < 0)

     {
       fprintf_unfiltered (gdb_stderr,
     {
       fprintf_unfiltered (gdb_stderr,

-                         "ERR: info io_registers NOT supported by current target\n");
+                         "ERR: info io_registers NOT supported by current "
+                          "target\n");

       return;
     }
       return;
     }

-
-  /* Just get the maximum buffer size. */
-  target_query ((int) 'R', 0, 0, &bufsiz);

   if (bufsiz > sizeof (buf))
     bufsiz = sizeof (buf);
 
   /* Find out how many io registers the target has. */
   strcpy (query, "avr.io_reg");
   if (bufsiz > sizeof (buf))
     bufsiz = sizeof (buf);
 
   /* Find out how many io registers the target has. */
   strcpy (query, "avr.io_reg");

-  target_query ((int) 'R', query, buf, &bufsiz);
+  target_read_partial (&current_target, TARGET_OBJECT_AVR, query, buf, 0,
+                      bufsiz);

 
   if (strncmp (buf, "", bufsiz) == 0)
     {
 
   if (strncmp (buf, "", bufsiz) == 0)
     {


@@ -1337,10 +1376,14 @@ avr_io_reg_read_command (char *args, int from_tty)
 
   for (i = 0; i < nreg; i += step)
     {
 
   for (i = 0; i < nreg; i += step)
     {

-      j = step - (nreg % step);        /* how many registers this round? */
+      /* how many registers this round? */
+      j = step;
+      if ((i+j) >= nreg)
+        j = nreg - i;           /* last block is less than 8 registers */

 
       snprintf (query, sizeof (query) - 1, "avr.io_reg:%x,%x", i, j);
 
       snprintf (query, sizeof (query) - 1, "avr.io_reg:%x,%x", i, j);

-      target_query ((int) 'R', query, buf, &bufsiz);
+      target_read_partial (&current_target, TARGET_OBJECT_AVR, query, buf,
+                          0, bufsiz);

 
       p = buf;
       for (k = i; k < (i + j); k++)
 
       p = buf;
       for (k = i; k < (i + j); k++)


@@ -1358,6 +1401,8 @@ avr_io_reg_read_command (char *args, int from_tty)
     }
 }
 
     }
 }
 

+extern initialize_file_ftype _initialize_avr_tdep; /* -Wmissing-prototypes */
+

 void
 _initialize_avr_tdep (void)
 {
 void
 _initialize_avr_tdep (void)
 {