Wed Oct 30 18:14:14 1996 Michael Snyder <msnyder@cleaver.cygnus.com>

        * m32r-tdep.c, m32r-rom.c: New files.
        * config/m32r/m32r.mt: New file.
        * config/m32r/tm-m32r.h: New file.

1 files changed, 380 insertions, 0 deletions

diff --git a/gdb/m32r-tdep.c b/gdb/m32r-tdep.c
new file mode 100644
index 0000000..a449223
--- /dev/null
+++ b/gdb/m32r-tdep.c
@@ -0,0 +1,380 @@
+/* Target-dependent code for the Mitsubishi m32r for GDB, the GNU debugger.
+   Copyright 1996, 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.  */
+
+#include "defs.h"
+#include "frame.h"
+#include "inferior.h"
+#include "obstack.h"
+#include "target.h"
+#include "value.h"
+#include "bfd.h"
+#include "gdb_string.h"
+#include "gdbcore.h"
+#include "symfile.h"
+
+struct dummy_frame
+{
+  struct dummy_frame *next;
+
+  CORE_ADDR fp;
+  CORE_ADDR sp;
+  CORE_ADDR rp;
+  CORE_ADDR pc;
+};
+
+void 
+m32r_frame_find_saved_regs PARAMS ((struct frame_info *fi, 
+				    struct frame_saved_regs *regaddr))
+{
+  *regaddr = fi->fsr;
+}
+
+static struct dummy_frame *dummy_frame_stack = NULL;
+
+/* Find end of function prologue */
+
+CORE_ADDR
+m32r_skip_prologue (pc)
+     CORE_ADDR pc;
+{
+  CORE_ADDR func_addr, func_end;
+  struct symtab_and_line sal;
+
+  /* See what the symbol table says */
+
+  if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+    {
+      sal = find_pc_line (func_addr, 0);
+
+      if (sal.line != 0 && sal.end < func_end)
+	return sal.end;
+      else
+	/* Either there's no line info, or the line after the prologue is after
+	   the end of the function.  In this case, there probably isn't a
+	   prologue.  */
+	return pc;
+    }
+
+  /* We can't find the start of this function, so there's nothing we can do. */
+  return pc;
+}
+
+/* This function decodes the target function prologue to determine
+   1) the size of the stack frame, and 2) which registers are saved on it.
+   It saves the offsets of saved regs in the frame_saved_regs argument,
+   and returns the frame size.
+*/
+
+static unsigned long
+m32r_scan_prologue (fi, fsr)
+     struct frame_info *fi;
+     struct frame_saved_regs *fsr;
+{
+  struct symtab_and_line sal;
+  CORE_ADDR prologue_start, prologue_end, current_pc;
+  unsigned long framesize;
+
+  /* this code essentially duplicates skip_prologue, 
+     but we need the start address below.  */
+
+  if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end))
+    {
+      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
+    prologue_end = prologue_start + 100; /* We're in the boondocks */
+
+  prologue_end = min (prologue_end, fi->pc);
+
+  /* Now, search the prologue looking for instructions that setup fp, save
+     rp (and other regs), adjust sp and such. */ 
+
+  framesize = 0;
+  memset (fsr->regs, '\000', sizeof fsr->regs);
+
+  for (current_pc = prologue_start; current_pc < prologue_end; current_pc += 2)
+    {
+      int insn;
+      int regno;
+
+      insn = read_memory_unsigned_integer (current_pc, 2);
+      if (insn & 0x80)				/* Four byte instruction? */
+	current_pc += 2;
+
+      if ((insn & 0xf0ff) == 0x207f) {		/* st reg, @-sp */
+	framesize += 4;
+	regno = ((insn >> 8) & 0xf);
+	fsr->regs[regno] = framesize;
+      }
+      else if ((insn >> 8) == 0x4f)  {		/* addi sp */
+	framesize += -((char) (insn & 0xff));	/* offset  */
+	break;					/* end of stack adjustments */
+      }
+    }
+  return framesize;
+}
+
+/* This function actually figures out the frame address for a given pc and
+   sp.  This is tricky on the v850 because we only use an explicit frame
+   pointer when using alloca().  The only reliable way to get this info is to
+   examine the prologue.
+*/
+
+void
+m32r_init_extra_frame_info (fi)
+     struct frame_info *fi;
+{
+  int reg;
+  int framesize;
+
+  if (fi->next)
+    fi->pc = FRAME_SAVED_PC (fi->next);
+
+  framesize = m32r_scan_prologue (fi, &fi->fsr);
+
+  if (PC_IN_CALL_DUMMY (fi->pc, NULL, NULL))
+    fi->frame = dummy_frame_stack->sp;
+  else if (!fi->next)
+    fi->frame = read_register (SP_REGNUM);
+
+  for (reg = 0; reg < NUM_REGS; reg++)
+    if (fi->fsr.regs[reg] != 0)
+      fi->fsr.regs[reg] = fi->frame + framesize - fi->fsr.regs[reg];
+}
+
+/* Find the caller of this frame.  We do this by seeing if RP_REGNUM is saved
+   in the stack anywhere, otherwise we get it from the registers. */
+
+CORE_ADDR
+m32r_find_callers_reg (fi, regnum)
+     struct frame_info *fi;
+     int regnum;
+{
+#if 0
+  /* XXX - Won't work if multiple dummy frames are active */
+  if (PC_IN_CALL_DUMMY (fi->pc, NULL, NULL))
+    switch (regnum)
+      {
+      case SP_REGNUM:
+	return dummy_frame_stack->sp;
+	break;
+      case FP_REGNUM:
+	return dummy_frame_stack->fp;
+	break;
+      case RP_REGNUM:
+	return dummy_frame_stack->pc;
+	break;
+      case PC_REGNUM:
+	return dummy_frame_stack->pc;
+	break;
+      }
+
+#endif
+  for (; fi; fi = fi->next)
+    if (fi->fsr.regs[regnum] != 0)
+      return read_memory_integer (fi->fsr.regs[regnum], 4);
+  return read_register (regnum);
+}
+
+/* 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.
+   For m32r, simply get the saved FP off the stack.
+ */
+
+CORE_ADDR
+m32r_frame_chain (fi)
+     struct frame_info *fi;
+{
+  CORE_ADDR saved_fp = fi->fsr.regs[FP_REGNUM];
+
+  if (saved_fp == 0)
+    return 0;		/* frameless assembly language fn (such as _start) */
+
+  return read_memory_integer (saved_fp, 4);
+}
+
+/* All we do here is record SP and FP on the call dummy stack */
+
+void
+m32r_push_dummy_frame ()
+{
+  struct dummy_frame *dummy_frame;
+
+  dummy_frame = xmalloc (sizeof (struct dummy_frame));
+
+  dummy_frame->fp = read_register (FP_REGNUM);
+  dummy_frame->sp = read_register (SP_REGNUM);
+  dummy_frame->rp = read_register (RP_REGNUM);
+  dummy_frame->pc = read_register (PC_REGNUM);
+  dummy_frame->next = dummy_frame_stack;
+  dummy_frame_stack = dummy_frame;
+}
+
+/*
+ * MISSING FUNCTION HEADER COMMENT
+ */
+
+int
+m32r_pc_in_call_dummy (pc)
+     CORE_ADDR pc;
+{
+  return dummy_frame_stack
+	 && pc >= CALL_DUMMY_ADDRESS ()
+	 && pc <= CALL_DUMMY_ADDRESS () + DECR_PC_AFTER_BREAK;
+}
+
+/* Discard from the stack the innermost frame,
+   restoring all saved registers.  */
+
+struct frame_info *
+m32r_pop_frame (frame)
+     struct frame_info *frame;
+{
+  int regnum;
+
+#if 0
+  if (PC_IN_CALL_DUMMY (frame->pc, NULL, NULL))
+    {
+      struct dummy_frame *dummy_frame;
+      
+      dummy_frame = dummy_frame_stack;
+      if (!dummy_frame)
+	error ("Can't pop dummy frame!");
+
+      dummy_frame_stack = dummy_frame->next;
+
+      write_register (FP_REGNUM, dummy_frame->fp);
+      write_register (SP_REGNUM, dummy_frame->sp);
+      write_register (RP_REGNUM, dummy_frame->rp);
+      write_register (PC_REGNUM, dummy_frame->pc);
+
+      free (dummy_frame);
+
+      flush_cached_frames ();
+
+      return NULL;
+    }
+
+#endif
+  write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
+
+  for (regnum = 0; regnum < NUM_REGS; regnum++)
+    if (frame->fsr.regs[regnum] != 0)
+      write_register (regnum, 
+		      read_memory_integer (frame->fsr.regs[regnum], 4));
+
+  write_register (SP_REGNUM, read_register (FP_REGNUM));
+  if (read_register (PSW_REGNUM) & 0x80)
+    write_register (SPU_REGNUM, read_register (SP_REGNUM));
+  else
+    write_register (SPI_REGNUM, read_register (SP_REGNUM));
+  /*  registers_changed (); */
+  flush_cached_frames ();
+
+  return NULL;
+}
+
+/* Put arguments in the right places, and setup return address register (RP) to
+   point at a convenient place to put a breakpoint.  First four args go in
+   R6->R9, subsequent args go into sp + 16 -> sp + ...  Structs are passed by
+   reference.  64 bit quantities (doubles and long longs) may be split between
+   the regs and the stack.  When calling a function that returns a struct, a
+   pointer to the struct is passed in as a secret first argument (always in R6).
+
+   By the time we get here, stack space has been allocated for the args, but
+   not for the struct return pointer.  */
+
+CORE_ADDR
+m32r_push_arguments (nargs, args, sp, struct_return, struct_addr)
+     int nargs;
+     value_ptr *args;
+     CORE_ADDR sp;
+     unsigned char struct_return;
+     CORE_ADDR struct_addr;
+{
+  int argreg;
+  int argnum;
+
+  argreg = ARG0_REGNUM;
+
+#if 0
+  if (struct_return)
+    {
+      write_register (argreg++, struct_addr);
+      sp -= 4;
+    }
+
+  for (argnum = 0; argnum < nargs; argnum++)
+    {
+      int len;
+      char *val;
+      char valbuf[4];
+
+      if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT
+	  && TYPE_LENGTH (VALUE_TYPE (*args)) > 8)
+	{
+	  store_address (valbuf, 4, VALUE_ADDRESS (*args));
+	  len = 4;
+	  val = valbuf;
+	}
+      else
+	{
+	  len = TYPE_LENGTH (VALUE_TYPE (*args));
+	  val = (char *)VALUE_CONTENTS (*args);
+	}
+
+      while (len > 0)
+	if  (argreg <= ARGLAST_REGNUM)
+	  {
+	    CORE_ADDR regval;
+
+	    regval = extract_address (val, REGISTER_RAW_SIZE (argreg));
+	    write_register (argreg, regval);
+
+	    len -= REGISTER_RAW_SIZE (argreg);
+	    val += REGISTER_RAW_SIZE (argreg);
+	    argreg++;
+	  }
+	else
+	  {
+	    write_memory (sp + argnum * 4, val, 4);
+
+	    len -= 4;
+	    val += 4;
+	  }
+      args++;
+    }
+
+  write_register (RP_REGNUM, entry_point_address ());
+
+#endif
+  return sp;
+}
+
+void
+_initialize_m32r_tdep ()
+{
+  tm_print_insn = print_insn_m32r;
+}