Restore h8300 support

1 files changed, 1457 insertions, 0 deletions

diff --git a/gdb/h8300-tdep.c b/gdb/h8300-tdep.c
new file mode 100644
index 0000000..2a83f03
--- /dev/null
+++ b/gdb/h8300-tdep.c
@@ -0,0 +1,1457 @@
+/* Target-machine dependent code for Renesas H8/300, for GDB.
+
+   Copyright 1988, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
+   1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/*
+   Contributed by Steve Chamberlain
+   sac@cygnus.com
+ */
+
+#include "defs.h"
+#include "value.h"
+#include "inferior.h"
+#include "symfile.h"
+#include "arch-utils.h"
+#include "regcache.h"
+#include "gdbcore.h"
+#include "objfiles.h"
+#include "gdbcmd.h"
+#include "gdb_assert.h"
+#include "dis-asm.h"
+#include "dwarf2-frame.h"
+#include "frame.h"
+#include "frame-base.h"
+#include "frame-unwind.h"
+
+/* Extra info which is saved in each frame_info. */
+struct frame_extra_info
+{
+  CORE_ADDR from_pc;
+};
+
+enum
+{
+  h8300_reg_size = 2,
+  h8300h_reg_size = 4,
+  h8300_max_reg_size = 4,
+};
+
+static int is_h8300hmode (struct gdbarch *gdbarch);
+static int is_h8300smode (struct gdbarch *gdbarch);
+static int is_h8300sxmode (struct gdbarch *gdbarch);
+static int is_h8300_normal_mode (struct gdbarch *gdbarch);
+
+#define BINWORD (is_h8300hmode (current_gdbarch) && \
+		  !is_h8300_normal_mode (current_gdbarch) ? h8300h_reg_size : h8300_reg_size)
+
+enum gdb_regnum
+{
+  E_R0_REGNUM, E_ER0_REGNUM = E_R0_REGNUM, E_ARG0_REGNUM = E_R0_REGNUM,
+  E_RET0_REGNUM = E_R0_REGNUM,
+  E_R1_REGNUM, E_ER1_REGNUM = E_R1_REGNUM, E_RET1_REGNUM = E_R1_REGNUM,
+  E_R2_REGNUM, E_ER2_REGNUM = E_R2_REGNUM, E_ARGLAST_REGNUM = E_R2_REGNUM,
+  E_R3_REGNUM, E_ER3_REGNUM = E_R3_REGNUM,
+  E_R4_REGNUM, E_ER4_REGNUM = E_R4_REGNUM,
+  E_R5_REGNUM, E_ER5_REGNUM = E_R5_REGNUM,
+  E_R6_REGNUM, E_ER6_REGNUM = E_R6_REGNUM, E_FP_REGNUM = E_R6_REGNUM,
+  E_SP_REGNUM,
+  E_CCR_REGNUM,
+  E_PC_REGNUM,
+  E_CYCLES_REGNUM,
+  E_TICK_REGNUM, E_EXR_REGNUM = E_TICK_REGNUM,
+  E_INST_REGNUM, E_TICKS_REGNUM = E_INST_REGNUM,
+  E_INSTS_REGNUM,
+  E_MACH_REGNUM,
+  E_MACL_REGNUM,
+  E_SBR_REGNUM,
+  E_VBR_REGNUM
+};
+
+#define H8300_MAX_NUM_REGS 18
+
+#define E_PSEUDO_CCR_REGNUM (NUM_REGS)
+#define E_PSEUDO_EXR_REGNUM (NUM_REGS+1)
+
+#define UNSIGNED_SHORT(X) ((X) & 0xffff)
+
+#define IS_PUSH(x) ((x & 0xfff0)==0x6df0)
+#define IS_PUSH_FP(x) (x == 0x6df6)
+#define IS_MOVE_FP(x) (x == 0x0d76 || x == 0x0ff6)
+#define IS_MOV_SP_FP(x) (x == 0x0d76 || x == 0x0ff6)
+#define IS_SUB2_SP(x) (x==0x1b87)
+#define IS_SUB4_SP(x) (x==0x1b97)
+#define IS_SUBL_SP(x) (x==0x7a37)
+#define IS_MOVK_R5(x) (x==0x7905)
+#define IS_SUB_R5SP(x) (x==0x1957)
+
+/* If the instruction at PC is an argument register spill, return its
+   length.  Otherwise, return zero.
+
+   An argument register spill is an instruction that moves an argument
+   from the register in which it was passed to the stack slot in which
+   it really lives.  It is a byte, word, or longword move from an
+   argument register to a negative offset from the frame pointer.
+   
+   CV, 2003-06-16: Or, in optimized code or when the `register' qualifier
+   is used, it could be a byte, word or long move to registers r3-r5.  */
+
+static int
+h8300_is_argument_spill (CORE_ADDR pc)
+{
+  int w = read_memory_unsigned_integer (pc, 2);
+
+  if (((w & 0xff88) == 0x0c88	/* mov.b Rsl, Rdl */
+       || (w & 0xff88) == 0x0d00	/* mov.w Rs, Rd */
+       || (w & 0xff88) == 0x0f80)	/* mov.l Rs, Rd */
+      && (w & 0x70) <= 0x20	/* Rs is R0, R1 or R2 */
+      && (w & 0x7) >= 0x3 && (w & 0x7) <= 0x5)	/* Rd is R3, R4 or R5 */
+    return 2;
+
+  if ((w & 0xfff0) == 0x6ee0	/* mov.b Rs,@(d:16,er6) */
+      && 8 <= (w & 0xf) && (w & 0xf) <= 10)	/* Rs is R0L, R1L, or R2L  */
+    {
+      int w2 = read_memory_integer (pc + 2, 2);
+
+      /* ... and d:16 is negative.  */
+      if (w2 < 0)
+	return 4;
+    }
+  else if (w == 0x7860)
+    {
+      int w2 = read_memory_integer (pc + 2, 2);
+
+      if ((w2 & 0xfff0) == 0x6aa0)	/* mov.b Rs, @(d:24,er6) */
+	{
+	  LONGEST disp = read_memory_integer (pc + 4, 4);
+
+	  /* ... and d:24 is negative.  */
+	  if (disp < 0 && disp > 0xffffff)
+	    return 8;
+	}
+    }
+  else if ((w & 0xfff0) == 0x6fe0	/* mov.w Rs,@(d:16,er6) */
+	   && (w & 0xf) <= 2)	/* Rs is R0, R1, or R2 */
+    {
+      int w2 = read_memory_integer (pc + 2, 2);
+
+      /* ... and d:16 is negative.  */
+      if (w2 < 0)
+	return 4;
+    }
+  else if (w == 0x78e0)
+    {
+      int w2 = read_memory_integer (pc + 2, 2);
+
+      if ((w2 & 0xfff0) == 0x6ba0)	/* mov.b Rs, @(d:24,er6) */
+	{
+	  LONGEST disp = read_memory_integer (pc + 4, 4);
+
+	  /* ... and d:24 is negative.  */
+	  if (disp < 0 && disp > 0xffffff)
+	    return 8;
+	}
+    }
+  else if (w == 0x0100)
+    {
+      int w2 = read_memory_integer (pc + 2, 2);
+
+      if ((w2 & 0xfff0) == 0x6fe0	/* mov.l Rs,@(d:16,er6) */
+	  && (w2 & 0xf) <= 2)	/* Rs is ER0, ER1, or ER2 */
+	{
+	  int w3 = read_memory_integer (pc + 4, 2);
+
+	  /* ... and d:16 is negative.  */
+	  if (w3 < 0)
+	    return 6;
+	}
+      else if (w2 == 0x78e0)
+	{
+	  int w3 = read_memory_integer (pc + 4, 2);
+
+	  if ((w3 & 0xfff0) == 0x6ba0)	/* mov.l Rs, @(d:24,er6) */
+	    {
+	      LONGEST disp = read_memory_integer (pc + 6, 4);
+
+	      /* ... and d:24 is negative.  */
+	      if (disp < 0 && disp > 0xffffff)
+		return 10;
+	    }
+	}
+    }
+
+  return 0;
+}
+
+static CORE_ADDR
+h8300_skip_prologue (CORE_ADDR start_pc)
+{
+  short int w;
+  int adjust = 0;
+
+  /* Skip past all push and stm insns.  */
+  while (1)
+    {
+      w = read_memory_unsigned_integer (start_pc, 2);
+      /* First look for push insns.  */
+      if (w == 0x0100 || w == 0x0110 || w == 0x0120 || w == 0x0130)
+	{
+	  w = read_memory_unsigned_integer (start_pc + 2, 2);
+	  adjust = 2;
+	}
+
+      if (IS_PUSH (w))
+	{
+	  start_pc += 2 + adjust;
+	  w = read_memory_unsigned_integer (start_pc, 2);
+	  continue;
+	}
+      adjust = 0;
+      break;
+    }
+
+  /* Skip past a move to FP, either word or long sized */
+  w = read_memory_unsigned_integer (start_pc, 2);
+  if (w == 0x0100)
+    {
+      w = read_memory_unsigned_integer (start_pc + 2, 2);
+      adjust += 2;
+    }
+
+  if (IS_MOVE_FP (w))
+    {
+      start_pc += 2 + adjust;
+      w = read_memory_unsigned_integer (start_pc, 2);
+    }
+
+  /* Check for loading either a word constant into r5;
+     long versions are handled by the SUBL_SP below.  */
+  if (IS_MOVK_R5 (w))
+    {
+      start_pc += 2;
+      w = read_memory_unsigned_integer (start_pc, 2);
+    }
+
+  /* Now check for subtracting r5 from sp, word sized only.  */
+  if (IS_SUB_R5SP (w))
+    {
+      start_pc += 2 + adjust;
+      w = read_memory_unsigned_integer (start_pc, 2);
+    }
+
+  /* Check for subs #2 and subs #4. */
+  while (IS_SUB2_SP (w) || IS_SUB4_SP (w))
+    {
+      start_pc += 2 + adjust;
+      w = read_memory_unsigned_integer (start_pc, 2);
+    }
+
+  /* Check for a 32bit subtract.  */
+  if (IS_SUBL_SP (w))
+    start_pc += 6 + adjust;
+
+  /* Skip past another possible stm insn for registers R3 to R5 (possibly used
+     for register qualified arguments.  */
+  w = read_memory_unsigned_integer (start_pc, 2);
+  /* First look for push insns.  */
+  if (w == 0x0110 || w == 0x0120 || w == 0x0130)
+    {
+      w = read_memory_unsigned_integer (start_pc + 2, 2);
+      if (IS_PUSH (w) && (w & 0xf) >= 0x3 && (w & 0xf) <= 0x5)
+	start_pc += 4;
+    }
+
+  /* Check for spilling an argument register to the stack frame.
+     This could also be an initializing store from non-prologue code,
+     but I don't think there's any harm in skipping that.  */
+  for (;;)
+    {
+      int spill_size = h8300_is_argument_spill (start_pc);
+      if (spill_size == 0)
+	break;
+      start_pc += spill_size;
+    }
+
+  return start_pc;
+}
+
+static CORE_ADDR
+h8300_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+  char buf[8];
+
+  frame_unwind_register (next_frame, E_PC_REGNUM, buf);
+  return extract_typed_address (buf, builtin_type_void_func_ptr);
+}
+
+static struct frame_id
+h8300_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+  char buf[4];
+  CORE_ADDR fp;
+
+  frame_unwind_register (next_frame, E_FP_REGNUM, buf);
+  fp = extract_unsigned_integer (buf, 4);
+
+  return frame_id_build (fp, frame_pc_unwind (next_frame));
+}
+
+struct h8300_frame_cache
+{
+  /* Base address.  */
+  CORE_ADDR base;
+  CORE_ADDR sp_offset;
+  CORE_ADDR pc;
+
+  /* Saved registers.  */
+  CORE_ADDR saved_regs[H8300_MAX_NUM_REGS];
+  CORE_ADDR saved_sp;
+
+  /* Stack space reserved for local variables.  */
+  long locals;
+};
+
+/* Normal frames.  */
+
+/* Allocate and initialize a frame cache.  */
+
+static struct h8300_frame_cache *
+h8300_alloc_frame_cache (void)
+{
+  struct h8300_frame_cache *cache;
+  int i;
+
+  cache = FRAME_OBSTACK_ZALLOC (struct h8300_frame_cache);
+
+  /* Base address.  */
+  cache->base = 0;
+  cache->sp_offset = -4;
+  cache->pc = 0;
+
+  /* Saved registers.  We initialize these to -1 since zero is a valid
+     offset (that's where %fp is supposed to be stored).  */
+  for (i = 0; i < NUM_REGS; i++)
+    cache->saved_regs[i] = -1;
+
+  /* Frameless until proven otherwise.  */
+  cache->locals = -1;
+
+  return cache;
+}
+
+/* Check whether PC points at a code that sets up a new stack frame.
+   If so, it updates CACHE and returns the address of the first
+   instruction after the sequence that sets removes the "hidden"
+   argument from the stack or CURRENT_PC, whichever is smaller.
+   Otherwise, return PC.  */
+
+static CORE_ADDR
+h8300_analyze_frame_setup (CORE_ADDR pc, CORE_ADDR current_pc,
+			   struct h8300_frame_cache *cache)
+{
+  unsigned int op;
+  int subs_count;
+
+  if (pc >= current_pc)
+    return current_pc;
+
+  op = read_memory_unsigned_integer (pc, 4);
+
+  if (op == 0x6df60d76)
+    {
+      /* mov.w r6,@-sp; mov.w sp,r6 */
+      cache->saved_regs[E_FP_REGNUM] = 0;
+      cache->sp_offset += 2;
+      op = read_memory_unsigned_integer (pc + 4, 4);
+      if (((op >> 16) & 0xfff0) == 0x7900)
+	{
+	  /* mov.w #imm,rN */
+	  cache->locals = -(short) (op & 0xffff);
+	  return pc + 8;
+	}
+      else if ((op >> 16) == 0x1b87)
+	{
+	  /* subs #2,sp */
+	  for (cache->locals = 0, pc += 4;
+	       read_memory_unsigned_integer (pc, 2) == 0x1b87;
+	       pc += 2, cache->locals += 2);
+	  return pc;
+	}
+    }
+  else if (op == 0x01006df6)
+    {
+      /* mov.l er6,@-sp */
+      op = read_memory_unsigned_integer (pc + 4, 2);
+      if (op == 0x0ff6)
+	{
+	  /* mov.l sp,er6 */
+	  op = read_memory_unsigned_integer (pc + 6, 2);
+	  if (op == 0x7a17)
+	    {
+	      /* add.l #-n,sp */
+	      cache->locals = -read_memory_unsigned_integer (pc + 8, 4);
+	      return pc + 12;
+	    }
+	  else if (op == 0x1b97)
+	    {
+	      /* subs #4,sp */
+	      for (cache->locals = 0, pc += 6;
+		   read_memory_unsigned_integer (pc, 2) == 0x1b97;
+		   pc += 2, cache->locals += 2);
+	      return pc;
+	    }
+	}
+    }
+
+  return pc;
+}
+
+/* Check whether PC points at code that saves registers on the stack.
+   If so, it updates CACHE and returns the address of the first
+   instruction after the register saves or CURRENT_PC, whichever is
+   smaller.  Otherwise, return PC.  */
+
+static CORE_ADDR
+h8300_analyze_register_saves (CORE_ADDR pc, CORE_ADDR current_pc,
+			      struct h8300_frame_cache *cache)
+{
+  if (cache->locals >= 0)
+    {
+      CORE_ADDR offset;
+      int op;
+      int i, regno;
+
+      offset = -cache->locals;
+      while (pc < current_pc)
+	{
+	  op = read_memory_unsigned_integer (pc, 2);
+	  if ((op & 0xfff0) == 0x6df0)
+	    {
+	      /* mov.w rN,@-sp */
+	      regno = op & 0x000f;
+	      cache->saved_regs[regno] = offset;
+	      offset -= 2;
+	      pc += 2;
+	    }
+	  else if (op == 0x0100)
+	    {
+	      op = read_memory_unsigned_integer (pc + 2, 2);
+	      if ((op & 0xfff0) == 0x6df0)
+		{
+		  /* mov.l erN,@-sp */
+		  regno = op & 0x000f;
+		  cache->saved_regs[regno] = offset;
+		  offset -= 4;
+		  pc += 4;
+		}
+	      else
+		break;
+	    }
+	  else if ((op & 0xffcf) == 0x0100)
+	    {
+	      int op1;
+	      op1 = read_memory_unsigned_integer (pc + 2, 2);
+	      if ((op1 & 0xfff0) == 0x6df0)
+		{
+		  /* stm.l reglist,@-sp */
+		  i = ((op & 0x0030) >> 4) + 1;
+		  regno = op1 & 0x000f;
+		  for (; i > 0; regno++, --i)
+		    {
+		      cache->saved_regs[regno] = offset;
+		      offset -= 4;
+		    }
+		  pc += 4;
+		}
+	      else
+		break;
+	    }
+	  else
+	    break;
+	}
+    }
+  return pc;
+}
+
+
+/* Do a full analysis of the prologue at PC and update CACHE
+   accordingly.  Bail out early if CURRENT_PC is reached.  Return the
+   address where the analysis stopped.
+
+   We handle all cases that can be generated by gcc.
+
+   For allocating a stack frame:
+
+   mov.w r6,@-sp
+   mov.w sp,r6
+   mov.w #-n,rN
+   add.w rN,sp
+
+   mov.w r6,@-sp
+   mov.w sp,r6
+   subs  #2,sp
+   (repeat)
+
+   mov.l er6,@-sp
+   mov.l sp,er6
+   add.l #-n,sp
+
+   mov.w r6,@-sp
+   mov.w sp,r6
+   subs  #4,sp
+   (repeat)
+
+   For saving registers:
+
+   mov.w rN,@-sp
+   mov.l erN,@-sp
+   stm.l reglist,@-sp
+
+   For setting up the PIC register:
+
+   Future equivalence...
+
+   */
+
+static CORE_ADDR
+h8300_analyze_prologue (CORE_ADDR pc, CORE_ADDR current_pc,
+			struct h8300_frame_cache *cache)
+{
+  unsigned int op;
+
+  pc = h8300_analyze_frame_setup (pc, current_pc, cache);
+  pc = h8300_analyze_register_saves (pc, current_pc, cache);
+  if (pc >= current_pc)
+    return current_pc;
+
+  /* PIC support */
+
+  return pc;
+}
+
+static struct h8300_frame_cache *
+h8300_frame_cache (struct frame_info *next_frame, void **this_cache)
+{
+  struct h8300_frame_cache *cache;
+  char buf[4];
+  int i;
+
+  if (*this_cache)
+    return *this_cache;
+
+  cache = h8300_alloc_frame_cache ();
+  *this_cache = cache;
+
+  /* In principle, for normal frames, %fp holds the frame pointer,
+     which holds the base address for the current stack frame.
+     However, for functions that don't need it, the frame pointer is
+     optional.  For these "frameless" functions the frame pointer is
+     actually the frame pointer of the calling frame.  Signal
+     trampolines are just a special case of a "frameless" function.
+     They (usually) share their frame pointer with the frame that was
+     in progress when the signal occurred.  */
+
+  frame_unwind_register (next_frame, E_FP_REGNUM, buf);
+  cache->base = extract_unsigned_integer (buf, 4);
+  if (cache->base == 0)
+    return cache;
+
+  /* For normal frames, %pc is stored at 4(%fp).  */
+  cache->saved_regs[E_PC_REGNUM] = 4;
+
+  cache->pc = frame_func_unwind (next_frame);
+  if (cache->pc != 0)
+    h8300_analyze_prologue (cache->pc, frame_pc_unwind (next_frame), cache);
+
+  if (cache->locals < 0)
+    {
+      /* We didn't find a valid frame, which means that CACHE->base
+         currently holds the frame pointer for our calling frame.  If
+         we're at the start of a function, or somewhere half-way its
+         prologue, the function's frame probably hasn't been fully
+         setup yet.  Try to reconstruct the base address for the stack
+         frame by looking at the stack pointer.  For truly "frameless"
+         functions this might work too.  */
+
+      frame_unwind_register (next_frame, E_SP_REGNUM, buf);
+      cache->base = extract_unsigned_integer (buf, 4) + cache->sp_offset;
+    }
+
+  /* Now that we have the base address for the stack frame we can
+     calculate the value of %sp in the calling frame.  */
+  cache->saved_sp = cache->base;
+
+  /* Adjust all the saved registers such that they contain addresses
+     instead of offsets.  */
+  for (i = 0; i < NUM_REGS; i++)
+    if (cache->saved_regs[i] != -1)
+      cache->saved_regs[i] += cache->base;
+
+  return cache;
+}
+
+static void
+h8300_frame_this_id (struct frame_info *next_frame, void **this_cache,
+		     struct frame_id *this_id)
+{
+  struct h8300_frame_cache *cache =
+    h8300_frame_cache (next_frame, this_cache);
+
+  /* This marks the outermost frame.  */
+  if (cache->base == 0)
+    return;
+
+  /* See the end of m68k_push_dummy_call.  */
+  *this_id = frame_id_build (cache->base, cache->pc);
+}
+
+static void
+h8300_frame_prev_register (struct frame_info *next_frame, void **this_cache,
+			   int regnum, int *optimizedp,
+			   enum lval_type *lvalp, CORE_ADDR *addrp,
+			   int *realnump, void *valuep)
+{
+  struct h8300_frame_cache *cache =
+    h8300_frame_cache (next_frame, this_cache);
+
+  gdb_assert (regnum >= 0);
+
+  if (regnum == E_SP_REGNUM && cache->saved_sp)
+    {
+      *optimizedp = 0;
+      *lvalp = not_lval;
+      *addrp = 0;
+      *realnump = -1;
+      if (valuep)
+	{
+	  /* Store the value.  */
+	  store_unsigned_integer (valuep, 4, cache->saved_sp);
+	}
+      return;
+    }
+
+  if (regnum < NUM_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);
+}
+
+static const struct frame_unwind h8300_frame_unwind = {
+  NORMAL_FRAME,
+  h8300_frame_this_id,
+  h8300_frame_prev_register
+};
+
+static const struct frame_unwind *
+h8300_frame_sniffer (struct frame_info *next_frame)
+{
+  return &h8300_frame_unwind;
+}
+
+/* Function: push_dummy_call
+   Setup the function arguments for calling a function in the inferior.
+   In this discussion, a `word' is 16 bits on the H8/300s, and 32 bits
+   on the H8/300H.
+
+   There are actually two ABI's here: -mquickcall (the default) and
+   -mno-quickcall.  With -mno-quickcall, all arguments are passed on
+   the stack after the return address, word-aligned.  With
+   -mquickcall, GCC tries to use r0 -- r2 to pass registers.  Since
+   GCC doesn't indicate in the object file which ABI was used to
+   compile it, GDB only supports the default --- -mquickcall.
+
+   Here are the rules for -mquickcall, in detail:
+
+   Each argument, whether scalar or aggregate, is padded to occupy a
+   whole number of words.  Arguments smaller than a word are padded at
+   the most significant end; those larger than a word are padded at
+   the least significant end.
+
+   The initial arguments are passed in r0 -- r2.  Earlier arguments go in
+   lower-numbered registers.  Multi-word arguments are passed in
+   consecutive registers, with the most significant end in the
+   lower-numbered register.
+
+   If an argument doesn't fit entirely in the remaining registers, it
+   is passed entirely on the stack.  Stack arguments begin just after
+   the return address.  Once an argument has overflowed onto the stack
+   this way, all subsequent arguments are passed on the stack.
+
+   The above rule has odd consequences.  For example, on the h8/300s,
+   if a function takes two longs and an int as arguments:
+   - the first long will be passed in r0/r1,
+   - the second long will be passed entirely on the stack, since it
+     doesn't fit in r2,
+   - and the int will be passed on the stack, even though it could fit
+     in r2.
+
+   A weird exception: if an argument is larger than a word, but not a
+   whole number of words in length (before padding), it is passed on
+   the stack following the rules for stack arguments above, even if
+   there are sufficient registers available to hold it.  Stranger
+   still, the argument registers are still `used up' --- even though
+   there's nothing in them.
+
+   So, for example, on the h8/300s, if a function expects a three-byte
+   structure and an int, the structure will go on the stack, and the
+   int will go in r2, not r0.
+  
+   If the function returns an aggregate type (struct, union, or class)
+   by value, the caller must allocate space to hold the return value,
+   and pass the callee a pointer to this space as an invisible first
+   argument, in R0.
+
+   For varargs functions, the last fixed argument and all the variable
+   arguments are always passed on the stack.  This means that calls to
+   varargs functions don't work properly unless there is a prototype
+   in scope.
+
+   Basically, this ABI is not good, for the following reasons:
+   - You can't call vararg functions properly unless a prototype is in scope.
+   - Structure passing is inconsistent, to no purpose I can see.
+   - It often wastes argument registers, of which there are only three
+     to begin with.  */
+
+static CORE_ADDR
+h8300_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 = 0, stack_offset = 0;
+  int wordsize = BINWORD;
+  int reg = E_ARG0_REGNUM;
+  int argument;
+
+  /* First, make sure the stack is properly aligned.  */
+  sp = align_down (sp, wordsize);
+
+  /* Now make sure there's space on the stack for the arguments.  We
+     may over-allocate a little here, but that won't hurt anything.  */
+  for (argument = 0; argument < nargs; argument++)
+    stack_alloc += align_up (TYPE_LENGTH (value_type (args[argument])),
+			     wordsize);
+  sp -= stack_alloc;
+
+  /* Now load as many arguments as possible into registers, and push
+     the rest onto the stack.
+     If we're returning a structure by value, then we must pass a
+     pointer to the buffer for the return value as an invisible first
+     argument.  */
+  if (struct_return)
+    regcache_cooked_write_unsigned (regcache, reg++, struct_addr);
+
+  for (argument = 0; argument < nargs; argument++)
+    {
+      struct type *type = value_type (args[argument]);
+      int len = TYPE_LENGTH (type);
+      char *contents = (char *) value_contents (args[argument]);
+
+      /* Pad the argument appropriately.  */
+      int padded_len = align_up (len, wordsize);
+      char *padded = alloca (padded_len);
+
+      memset (padded, 0, padded_len);
+      memcpy (len < wordsize ? padded + padded_len - len : padded,
+	      contents, len);
+
+      /* Could the argument fit in the remaining registers?  */
+      if (padded_len <= (E_ARGLAST_REGNUM - reg + 1) * wordsize)
+	{
+	  /* Are we going to pass it on the stack anyway, for no good
+	     reason?  */
+	  if (len > wordsize && len % wordsize)
+	    {
+	      /* I feel so unclean.  */
+	      write_memory (sp + stack_offset, padded, padded_len);
+	      stack_offset += padded_len;
+
+	      /* That's right --- even though we passed the argument
+	         on the stack, we consume the registers anyway!  Love
+	         me, love my dog.  */
+	      reg += padded_len / wordsize;
+	    }
+	  else
+	    {
+	      /* Heavens to Betsy --- it's really going in registers!
+	         It would be nice if we could use write_register_bytes
+	         here, but on the h8/300s, there are gaps between
+	         the registers in the register file.  */
+	      int offset;
+
+	      for (offset = 0; offset < padded_len; offset += wordsize)
+		{
+		  ULONGEST word = extract_unsigned_integer (padded + offset,
+							    wordsize);
+		  regcache_cooked_write_unsigned (regcache, reg++, word);
+		}
+	    }
+	}
+      else
+	{
+	  /* It doesn't fit in registers!  Onto the stack it goes.  */
+	  write_memory (sp + stack_offset, padded, padded_len);
+	  stack_offset += padded_len;
+
+	  /* Once one argument has spilled onto the stack, all
+	     subsequent arguments go on the stack.  */
+	  reg = E_ARGLAST_REGNUM + 1;
+	}
+    }
+
+  /* Store return address.  */
+  sp -= wordsize;
+  write_memory_unsigned_integer (sp, wordsize, bp_addr);
+
+  /* Update stack pointer.  */
+  regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, sp);
+
+  return sp;
+}
+
+/* Function: extract_return_value
+   Figure out where in REGBUF the called function has left its return value.
+   Copy that into VALBUF.  Be sure to account for CPU type.   */
+
+static void
+h8300_extract_return_value (struct type *type, struct regcache *regcache,
+			    void *valbuf)
+{
+  int len = TYPE_LENGTH (type);
+  ULONGEST c, addr;
+
+  switch (len)
+    {
+    case 1:
+    case 2:
+      regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
+      store_unsigned_integer (valbuf, len, c);
+      break;
+    case 4:			/* Needs two registers on plain H8/300 */
+      regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
+      store_unsigned_integer (valbuf, 2, c);
+      regcache_cooked_read_unsigned (regcache, E_RET1_REGNUM, &c);
+      store_unsigned_integer ((void *) ((char *) valbuf + 2), 2, c);
+      break;
+    case 8:			/* long long is now 8 bytes.  */
+      if (TYPE_CODE (type) == TYPE_CODE_INT)
+	{
+	  regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &addr);
+	  c = read_memory_unsigned_integer ((CORE_ADDR) addr, len);
+	  store_unsigned_integer (valbuf, len, c);
+	}
+      else
+	{
+	  error ("I don't know how this 8 byte value is returned.");
+	}
+      break;
+    }
+}
+
+static void
+h8300h_extract_return_value (struct type *type, struct regcache *regcache,
+			     void *valbuf)
+{
+  int len = TYPE_LENGTH (type);
+  ULONGEST c, addr;
+
+  switch (len)
+    {
+    case 1:
+    case 2:
+    case 4:
+      regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
+      store_unsigned_integer (valbuf, len, c);
+      break;
+    case 8:			/* long long is now 8 bytes.  */
+      if (TYPE_CODE (type) == TYPE_CODE_INT)
+	{
+	  regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &addr);
+	  c = read_memory_unsigned_integer ((CORE_ADDR) addr, len);
+	  store_unsigned_integer (valbuf, len, c);
+	}
+      else
+	{
+	  error ("I don't know how this 8 byte value is returned.");
+	}
+      break;
+    }
+}
+
+
+/* Function: store_return_value
+   Place the appropriate value in the appropriate registers.
+   Primarily used by the RETURN command.  */
+
+static void
+h8300_store_return_value (struct type *type, struct regcache *regcache,
+			  const void *valbuf)
+{
+  int len = TYPE_LENGTH (type);
+  ULONGEST val;
+
+  switch (len)
+    {
+    case 1:
+    case 2:			/* short... */
+      val = extract_unsigned_integer (valbuf, len);
+      regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM, val);
+      break;
+    case 4:			/* long, float */
+      val = extract_unsigned_integer (valbuf, len);
+      regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM,
+				      (val >> 16) & 0xffff);
+      regcache_cooked_write_unsigned (regcache, E_RET1_REGNUM, val & 0xffff);
+      break;
+    case 8:			/* long long, double and long double are all defined
+				   as 4 byte types so far so this shouldn't happen.  */
+      error ("I don't know how to return an 8 byte value.");
+      break;
+    }
+}
+
+static void
+h8300h_store_return_value (struct type *type, struct regcache *regcache,
+			   const void *valbuf)
+{
+  int len = TYPE_LENGTH (type);
+  ULONGEST val;
+
+  switch (len)
+    {
+    case 1:
+    case 2:
+    case 4:			/* long, float */
+      val = extract_unsigned_integer (valbuf, len);
+      regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM, val);
+      break;
+    case 8:			/* long long, double and long double are all defined
+				   as 4 byte types so far so this shouldn't happen.  */
+      error ("I don't know how to return an 8 byte value.");
+      break;
+    }
+}
+
+static struct cmd_list_element *setmachinelist;
+
+static const char *
+h8300_register_name (int regno)
+{
+  /* The register names change depending on which h8300 processor
+     type is selected. */
+  static char *register_names[] = {
+    "r0", "r1", "r2", "r3", "r4", "r5", "r6",
+    "sp", "", "pc", "cycles", "tick", "inst",
+    "ccr",			/* pseudo register */
+  };
+  if (regno < 0
+      || regno >= (sizeof (register_names) / sizeof (*register_names)))
+    internal_error (__FILE__, __LINE__,
+		    "h8300_register_name: illegal register number %d", regno);
+  else
+    return register_names[regno];
+}
+
+static const char *
+h8300s_register_name (int regno)
+{
+  static char *register_names[] = {
+    "er0", "er1", "er2", "er3", "er4", "er5", "er6",
+    "sp", "", "pc", "cycles", "", "tick", "inst",
+    "mach", "macl",
+    "ccr", "exr"		/* pseudo registers */
+  };
+  if (regno < 0
+      || regno >= (sizeof (register_names) / sizeof (*register_names)))
+    internal_error (__FILE__, __LINE__,
+		    "h8300s_register_name: illegal register number %d",
+		    regno);
+  else
+    return register_names[regno];
+}
+
+static const char *
+h8300sx_register_name (int regno)
+{
+  static char *register_names[] = {
+    "er0", "er1", "er2", "er3", "er4", "er5", "er6",
+    "sp", "", "pc", "cycles", "", "tick", "inst",
+    "mach", "macl", "sbr", "vbr",
+    "ccr", "exr"		/* pseudo registers */
+  };
+  if (regno < 0
+      || regno >= (sizeof (register_names) / sizeof (*register_names)))
+    internal_error (__FILE__, __LINE__,
+		    "h8300sx_register_name: illegal register number %d",
+		    regno);
+  else
+    return register_names[regno];
+}
+
+static void
+h8300_print_register (struct gdbarch *gdbarch, struct ui_file *file,
+		      struct frame_info *frame, int regno)
+{
+  LONGEST rval;
+  const char *name = gdbarch_register_name (gdbarch, regno);
+
+  if (!name || !*name)
+    return;
+
+  rval = get_frame_register_signed (frame, regno);
+
+  fprintf_filtered (file, "%-14s ", name);
+  if ((regno == E_PSEUDO_CCR_REGNUM) || \
+      (regno == E_PSEUDO_EXR_REGNUM && is_h8300smode (current_gdbarch)))
+    {
+      fprintf_filtered (file, "0x%02x        ", (unsigned char) rval);
+      print_longest (file, 'u', 1, rval);
+    }
+  else
+    {
+      fprintf_filtered (file, "0x%s  ", phex ((ULONGEST) rval, BINWORD));
+      print_longest (file, 'd', 1, rval);
+    }
+  if (regno == E_PSEUDO_CCR_REGNUM)
+    {
+      /* CCR register */
+      int C, Z, N, V;
+      unsigned char l = rval & 0xff;
+      fprintf_filtered (file, "\t");
+      fprintf_filtered (file, "I-%d ", (l & 0x80) != 0);
+      fprintf_filtered (file, "UI-%d ", (l & 0x40) != 0);
+      fprintf_filtered (file, "H-%d ", (l & 0x20) != 0);
+      fprintf_filtered (file, "U-%d ", (l & 0x10) != 0);
+      N = (l & 0x8) != 0;
+      Z = (l & 0x4) != 0;
+      V = (l & 0x2) != 0;
+      C = (l & 0x1) != 0;
+      fprintf_filtered (file, "N-%d ", N);
+      fprintf_filtered (file, "Z-%d ", Z);
+      fprintf_filtered (file, "V-%d ", V);
+      fprintf_filtered (file, "C-%d ", C);
+      if ((C | Z) == 0)
+	fprintf_filtered (file, "u> ");
+      if ((C | Z) == 1)
+	fprintf_filtered (file, "u<= ");
+      if ((C == 0))
+	fprintf_filtered (file, "u>= ");
+      if (C == 1)
+	fprintf_filtered (file, "u< ");
+      if (Z == 0)
+	fprintf_filtered (file, "!= ");
+      if (Z == 1)
+	fprintf_filtered (file, "== ");
+      if ((N ^ V) == 0)
+	fprintf_filtered (file, ">= ");
+      if ((N ^ V) == 1)
+	fprintf_filtered (file, "< ");
+      if ((Z | (N ^ V)) == 0)
+	fprintf_filtered (file, "> ");
+      if ((Z | (N ^ V)) == 1)
+	fprintf_filtered (file, "<= ");
+    }
+  else if (regno == E_PSEUDO_EXR_REGNUM && is_h8300smode (current_gdbarch))
+    {
+      /* EXR register */
+      unsigned char l = rval & 0xff;
+      fprintf_filtered (file, "\t");
+      fprintf_filtered (file, "T-%d - - - ", (l & 0x80) != 0);
+      fprintf_filtered (file, "I2-%d ", (l & 4) != 0);
+      fprintf_filtered (file, "I1-%d ", (l & 2) != 0);
+      fprintf_filtered (file, "I0-%d", (l & 1) != 0);
+    }
+  fprintf_filtered (file, "\n");
+}
+
+static void
+h8300_print_registers_info (struct gdbarch *gdbarch, struct ui_file *file,
+			    struct frame_info *frame, int regno, int cpregs)
+{
+  if (regno < 0)
+    {
+      for (regno = E_R0_REGNUM; regno <= E_SP_REGNUM; ++regno)
+	h8300_print_register (gdbarch, file, frame, regno);
+      h8300_print_register (gdbarch, file, frame, E_PSEUDO_CCR_REGNUM);
+      h8300_print_register (gdbarch, file, frame, E_PC_REGNUM);
+      if (is_h8300smode (current_gdbarch))
+	{
+	  h8300_print_register (gdbarch, file, frame, E_PSEUDO_EXR_REGNUM);
+	  if (is_h8300sxmode (current_gdbarch))
+	    {
+	      h8300_print_register (gdbarch, file, frame, E_SBR_REGNUM);
+	      h8300_print_register (gdbarch, file, frame, E_VBR_REGNUM);
+	    }
+	  h8300_print_register (gdbarch, file, frame, E_MACH_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_MACL_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_CYCLES_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_TICKS_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_INSTS_REGNUM);
+	}
+      else
+	{
+	  h8300_print_register (gdbarch, file, frame, E_CYCLES_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_TICK_REGNUM);
+	  h8300_print_register (gdbarch, file, frame, E_INST_REGNUM);
+	}
+    }
+  else
+    {
+      if (regno == E_CCR_REGNUM)
+	h8300_print_register (gdbarch, file, frame, E_PSEUDO_CCR_REGNUM);
+      else if (regno == E_PSEUDO_EXR_REGNUM
+	       && is_h8300smode (current_gdbarch))
+	h8300_print_register (gdbarch, file, frame, E_PSEUDO_EXR_REGNUM);
+      else
+	h8300_print_register (gdbarch, file, frame, regno);
+    }
+}
+
+static struct type *
+h8300_register_type (struct gdbarch *gdbarch, int regno)
+{
+  if (regno < 0 || regno >= NUM_REGS + NUM_PSEUDO_REGS)
+    internal_error (__FILE__, __LINE__,
+		    "h8300_register_type: illegal register number %d", regno);
+  else
+    {
+      switch (regno)
+	{
+	case E_PC_REGNUM:
+	  return builtin_type_void_func_ptr;
+	case E_SP_REGNUM:
+	case E_FP_REGNUM:
+	  return builtin_type_void_data_ptr;
+	default:
+	  if (regno == E_PSEUDO_CCR_REGNUM)
+	    return builtin_type_uint8;
+	  else if (regno == E_PSEUDO_EXR_REGNUM)
+	    return builtin_type_uint8;
+	  else if (is_h8300hmode (current_gdbarch))
+	    return builtin_type_int32;
+	  else
+	    return builtin_type_int16;
+	}
+    }
+}
+
+static void
+h8300_pseudo_register_read (struct gdbarch *gdbarch,
+			    struct regcache *regcache, int regno, void *buf)
+{
+  if (regno == E_PSEUDO_CCR_REGNUM)
+    regcache_raw_read (regcache, E_CCR_REGNUM, buf);
+  else if (regno == E_PSEUDO_EXR_REGNUM)
+    regcache_raw_read (regcache, E_EXR_REGNUM, buf);
+  else
+    regcache_raw_read (regcache, regno, buf);
+}
+
+static void
+h8300_pseudo_register_write (struct gdbarch *gdbarch,
+			     struct regcache *regcache, int regno,
+			     const void *buf)
+{
+  if (regno == E_PSEUDO_CCR_REGNUM)
+    regcache_raw_write (regcache, E_CCR_REGNUM, buf);
+  else if (regno == E_PSEUDO_EXR_REGNUM)
+    regcache_raw_write (regcache, E_EXR_REGNUM, buf);
+  else
+    regcache_raw_write (regcache, regno, buf);
+}
+
+static int
+h8300_dbg_reg_to_regnum (int regno)
+{
+  if (regno == E_CCR_REGNUM)
+    return E_PSEUDO_CCR_REGNUM;
+  return regno;
+}
+
+static int
+h8300s_dbg_reg_to_regnum (int regno)
+{
+  if (regno == E_CCR_REGNUM)
+    return E_PSEUDO_CCR_REGNUM;
+  if (regno == E_EXR_REGNUM)
+    return E_PSEUDO_EXR_REGNUM;
+  return regno;
+}
+
+static CORE_ADDR
+h8300_extract_struct_value_address (struct regcache *regcache)
+{
+  ULONGEST addr;
+  regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &addr);
+  return addr;
+}
+
+const static unsigned char *
+h8300_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
+{
+  /*static unsigned char breakpoint[] = { 0x7A, 0xFF }; *//* ??? */
+  static unsigned char breakpoint[] = { 0x01, 0x80 };	/* Sleep */
+
+  *lenptr = sizeof (breakpoint);
+  return breakpoint;
+}
+
+static CORE_ADDR
+h8300_push_dummy_code (struct gdbarch *gdbarch,
+		       CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc,
+		       struct value **args, int nargs,
+		       struct type *value_type,
+		       CORE_ADDR *real_pc, CORE_ADDR *bp_addr)
+{
+  /* Allocate space sufficient for a breakpoint.  */
+  sp = (sp - 2) & ~1;
+  /* Store the address of that breakpoint */
+  *bp_addr = sp;
+  /* h8300 always starts the call at the callee's entry point.  */
+  *real_pc = funaddr;
+  return sp;
+}
+
+static void
+h8300_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
+			struct frame_info *frame, const char *args)
+{
+  fprintf_filtered (file, "\
+No floating-point info available for this processor.\n");
+}
+
+static struct gdbarch *
+h8300_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+  struct gdbarch_tdep *tdep = NULL;
+  struct gdbarch *gdbarch;
+
+  arches = gdbarch_list_lookup_by_info (arches, &info);
+  if (arches != NULL)
+    return arches->gdbarch;
+
+#if 0
+  tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep));
+#endif
+
+  if (info.bfd_arch_info->arch != bfd_arch_h8300)
+    return NULL;
+
+  gdbarch = gdbarch_alloc (&info, 0);
+
+  switch (info.bfd_arch_info->mach)
+    {
+    case bfd_mach_h8300:
+      set_gdbarch_num_regs (gdbarch, 13);
+      set_gdbarch_num_pseudo_regs (gdbarch, 1);
+      set_gdbarch_ecoff_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_dwarf_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_dwarf2_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_stab_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_register_name (gdbarch, h8300_register_name);
+      set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+      set_gdbarch_addr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+      set_gdbarch_extract_return_value (gdbarch, h8300_extract_return_value);
+      set_gdbarch_store_return_value (gdbarch, h8300_store_return_value);
+      set_gdbarch_print_insn (gdbarch, print_insn_h8300);
+      break;
+    case bfd_mach_h8300h:
+    case bfd_mach_h8300hn:
+      set_gdbarch_num_regs (gdbarch, 13);
+      set_gdbarch_num_pseudo_regs (gdbarch, 1);
+      set_gdbarch_ecoff_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_dwarf_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_dwarf2_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_stab_reg_to_regnum (gdbarch, h8300_dbg_reg_to_regnum);
+      set_gdbarch_register_name (gdbarch, h8300_register_name);
+      if (info.bfd_arch_info->mach != bfd_mach_h8300hn)
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	}
+      else
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	}
+      set_gdbarch_extract_return_value (gdbarch, h8300h_extract_return_value);
+      set_gdbarch_store_return_value (gdbarch, h8300h_store_return_value);
+      set_gdbarch_print_insn (gdbarch, print_insn_h8300h);
+      break;
+    case bfd_mach_h8300s:
+    case bfd_mach_h8300sn:
+      set_gdbarch_num_regs (gdbarch, 16);
+      set_gdbarch_num_pseudo_regs (gdbarch, 2);
+      set_gdbarch_ecoff_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_dwarf_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_dwarf2_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_stab_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_register_name (gdbarch, h8300s_register_name);
+      if (info.bfd_arch_info->mach != bfd_mach_h8300sn)
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	}
+      else
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	}
+      set_gdbarch_extract_return_value (gdbarch, h8300h_extract_return_value);
+      set_gdbarch_store_return_value (gdbarch, h8300h_store_return_value);
+      set_gdbarch_print_insn (gdbarch, print_insn_h8300s);
+      break;
+    case bfd_mach_h8300sx:
+    case bfd_mach_h8300sxn:
+      set_gdbarch_num_regs (gdbarch, 18);
+      set_gdbarch_num_pseudo_regs (gdbarch, 2);
+      set_gdbarch_ecoff_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_dwarf_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_dwarf2_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_stab_reg_to_regnum (gdbarch, h8300s_dbg_reg_to_regnum);
+      set_gdbarch_register_name (gdbarch, h8300sx_register_name);
+      if (info.bfd_arch_info->mach != bfd_mach_h8300sxn)
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+	}
+      else
+	{
+	  set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	  set_gdbarch_addr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+	}
+      set_gdbarch_extract_return_value (gdbarch, h8300h_extract_return_value);
+      set_gdbarch_store_return_value (gdbarch, h8300h_store_return_value);
+      set_gdbarch_print_insn (gdbarch, print_insn_h8300s);
+      break;
+    }
+
+  set_gdbarch_pseudo_register_read (gdbarch, h8300_pseudo_register_read);
+  set_gdbarch_pseudo_register_write (gdbarch, h8300_pseudo_register_write);
+
+  /*
+   * Basic register fields and methods.
+   */
+
+  set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM);
+  set_gdbarch_deprecated_fp_regnum (gdbarch, E_FP_REGNUM);
+  set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM);
+  set_gdbarch_register_type (gdbarch, h8300_register_type);
+  set_gdbarch_print_registers_info (gdbarch, h8300_print_registers_info);
+  set_gdbarch_print_float_info (gdbarch, h8300_print_float_info);
+
+  /*
+   * Frame Info
+   */
+  set_gdbarch_skip_prologue (gdbarch, h8300_skip_prologue);
+
+  /* Frame unwinder.  */
+  set_gdbarch_unwind_dummy_id (gdbarch, h8300_unwind_dummy_id);
+  set_gdbarch_unwind_pc (gdbarch, h8300_unwind_pc);
+
+  /* Hook in the DWARF CFI frame unwinder.  */
+  frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
+
+  /* 
+   * Miscelany
+   */
+  /* Stack grows up. */
+  set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+
+  set_gdbarch_deprecated_extract_struct_value_address (gdbarch,
+						       h8300_extract_struct_value_address);
+  set_gdbarch_deprecated_use_struct_convention (gdbarch,
+						always_use_struct_convention);
+  set_gdbarch_breakpoint_from_pc (gdbarch, h8300_breakpoint_from_pc);
+  set_gdbarch_push_dummy_code (gdbarch, h8300_push_dummy_code);
+  set_gdbarch_push_dummy_call (gdbarch, h8300_push_dummy_call);
+
+  set_gdbarch_int_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+  set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+  set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
+  set_gdbarch_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+  set_gdbarch_long_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+
+  set_gdbarch_believe_pcc_promotion (gdbarch, 1);
+
+  /* Char is unsigned.  */
+  set_gdbarch_char_signed (gdbarch, 0);
+
+  frame_unwind_append_sniffer (gdbarch, h8300_frame_sniffer);
+
+  return gdbarch;
+
+}
+
+extern initialize_file_ftype _initialize_h8300_tdep;	/* -Wmissing-prototypes */
+
+void
+_initialize_h8300_tdep (void)
+{
+  register_gdbarch_init (bfd_arch_h8300, h8300_gdbarch_init);
+}
+
+static int
+is_h8300hmode (struct gdbarch *gdbarch)
+{
+  return gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sx
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sxn
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300s
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sn
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300h
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300hn;
+}
+
+static int
+is_h8300smode (struct gdbarch *gdbarch)
+{
+  return gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sx
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sxn
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300s
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sn;
+}
+
+static int
+is_h8300sxmode (struct gdbarch *gdbarch)
+{
+  return gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sx
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sxn;
+}
+
+static int
+is_h8300_normal_mode (struct gdbarch *gdbarch)
+{
+  return gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sxn
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300sn
+    || gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_h8300hn;
+}