m68k.c

来自「gcc3.2.1源代码」· C语言 代码 · 共 2,431 行 · 第 1/5 页

         Using two movel instructions instead of a single moveml
         is about 15% faster for the 68020 and 68030 at no expense
         in code size.  */

      int i;

      /* Undo the work from above.  */
      for (i = 0; i< 16; i++)
        if (mask & (1 << i))
          {
            if (big)
	      fprintf (stream, "\tmove.l -%d(%s,a0.l),%s\n",
		       offset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       reg_names[i]);
            else if (! frame_pointer_needed)
	      fprintf (stream, "\tmove.l (sp)+,%s\n",
		       reg_names[i]);
            else
	      fprintf (stream, "\tmove.l -%d(%s),%s\n",
		       offset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       reg_names[i]);
            offset = offset - 4;
          }
    }
  else if (mask)
    {
      first = 1;
      for (regno = 0; regno < 16; regno++)
        if (mask & (1 << regno))
	  {
	    if (first && big)
	      {
		fprintf (stream, "\tmovem.l -%d(%s,a0.l),%s",
			 offset + fsize,
			 reg_names[FRAME_POINTER_REGNUM],
			 reg_names[regno]);
		first = 0;
	      }
	    else if (first && ! frame_pointer_needed)
	      {
		fprintf (stream, "\tmovem.l (sp)+,%s",
			 reg_names[regno]);
		first = 0;
	      }
	    else if (first)
	      {
		fprintf (stream, "\tmovem.l -%d(%s),%s",
			 offset + fsize,
			 reg_names[FRAME_POINTER_REGNUM],
			 reg_names[regno]);
		first = 0;
	      }
	    else
	      fprintf (stream, "/%s", reg_names[regno]);
	  }
      fprintf (stream, "\n");
    }

  if (fmask)
    {
      first = 1;
      for (regno = 16; regno < 24; regno++)
        if (fmask & (1 << (23 - regno)))
	  {
	    if (first && big)
	      {
		fprintf (stream, "\tfmovem.x -%d(%s,a0.l),%s",
			 foffset + fsize,
			 reg_names[FRAME_POINTER_REGNUM],
			 reg_names[regno]);
		first = 0;
	      }
	    else if (first && ! frame_pointer_needed)
	      {
		fprintf (stream, "\tfmovem.x (sp)+,%s",
			 reg_names[regno]);
		first = 0;
	      }
	    else if (first)
	      {
		fprintf (stream, "\tfmovem.x -%d(%s),%s",
			 foffset + fsize,
			 reg_names[FRAME_POINTER_REGNUM],
			 reg_names[regno]);
		first = 0;
	      }
	    else
	      fprintf (stream, "/%s", reg_names[regno]);
	  }
      fprintf (stream, "\n");
    }

  if (frame_pointer_needed)
    fprintf (stream, "\tunlk %s\n",
	     reg_names[FRAME_POINTER_REGNUM]);
  else if (fsize)
    {
      if (fsize + 4 < 0x8000)
	fprintf (stream, "\tadd.w #%d,sp\n", fsize + 4);
      else
	fprintf (stream, "\tadd.l #%d,sp\n", fsize + 4);
    }

  if (current_function_pops_args)
    fprintf (stream, "\trtd #%d\n", current_function_pops_args);
  else
    fprintf (stream, "\trts\n");
}

#else
#if defined (NEWS) && defined (MOTOROLA)

static void
m68k_output_function_epilogue (stream, size)
     FILE *stream;
     HOST_WIDE_INT size;
{
  register int regno;
  register int mask, fmask;
  register int nregs;
  HOST_WIDE_INT offset, foffset;
  HOST_WIDE_INT fsize = ((size) + 3) & -4;
  int big = 0;

  nregs = 0;  fmask = 0;
  for (regno = 16; regno < FIRST_PSEUDO_REGISTER; regno++)
    if (regs_ever_live[regno] && ! call_used_regs[regno])
      {
	nregs++;
	fmask |= 1 << (23 - regno);
      }

  foffset = nregs * 12;
  nregs = 0;  mask = 0;
  if (frame_pointer_needed)
    regs_ever_live[FRAME_POINTER_REGNUM] = 0;

  for (regno = 0; regno < 16; regno++)
    if (regs_ever_live[regno] && ! call_used_regs[regno])
      {
	nregs++;
	mask |= 1 << regno;
      }

  offset = foffset + nregs * 4;
  if (offset + fsize >= 0x8000
      && frame_pointer_needed
      && (mask || fmask))
    {
      fprintf (stream, "\tmove.l #%d,a0\n", -fsize);
      fsize = 0, big = 1;
    }

  if (exact_log2 (mask) >= 0)
    {
      if (big)
	fprintf (stream, "\tmove.l (-%d,fp,a0.l),%s\n",
		 offset + fsize, reg_names[exact_log2 (mask)]);
      else if (! frame_pointer_needed)
	fprintf (stream, "\tmove.l (sp)+,%s\n",
		 reg_names[exact_log2 (mask)]);
      else
	fprintf (stream, "\tmove.l (-%d,fp),%s\n",
		 offset + fsize, reg_names[exact_log2 (mask)]);
    }
  else if (mask)
    {
      if (big)
	fprintf (stream, "\tmovem.l (-%d,fp,a0.l),#0x%x\n",
		 offset + fsize, mask);
      else if (! frame_pointer_needed)
	fprintf (stream, "\tmovem.l (sp)+,#0x%x\n", mask);
      else
	fprintf (stream, "\tmovem.l (-%d,fp),#0x%x\n",
		 offset + fsize, mask);
    }

  if (fmask)
    {
      if (big)
	fprintf (stream, "\tfmovem.x (-%d,fp,a0.l),#0x%x\n",
		 foffset + fsize, fmask);
      else if (! frame_pointer_needed)
	fprintf (stream, "\tfmovem.x (sp)+,#0x%x\n", fmask);
      else
	fprintf (stream, "\tfmovem.x (-%d,fp),#0x%x\n",
		 foffset + fsize, fmask);
    }

  if (frame_pointer_needed)
    fprintf (stream, "\tunlk fp\n");
  else if (fsize)
    {
      if (fsize + 4 < 0x8000)
	fprintf (stream, "\tadd.w #%d,sp\n", fsize + 4);
      else
	fprintf (stream, "\tadd.l #%d,sp\n", fsize + 4);
    }

  if (current_function_pops_args)
    fprintf (stream, "\trtd #%d\n", current_function_pops_args);
  else
    fprintf (stream, "\trts\n");
}

#else  /* !CRDS && ! (NEWS && MOTOROLA) && ! (DPX2 && MOTOROLA) */

static void
m68k_output_function_epilogue (stream, size)
     FILE *stream;
     HOST_WIDE_INT size;
{
  register int regno;
  register int mask, fmask;
  register int nregs;
  HOST_WIDE_INT offset, foffset, fpoffset;
  HOST_WIDE_INT fsize = (size + 3) & -4;
  int big = 0;
  rtx insn = get_last_insn ();
  int restore_from_sp = 0;
  
  /* If the last insn was a BARRIER, we don't have to write any code.  */
  if (GET_CODE (insn) == NOTE)
    insn = prev_nonnote_insn (insn);
  if (insn && GET_CODE (insn) == BARRIER)
    {
      /* Output just a no-op so that debuggers don't get confused
	 about which function the pc is in at this address.  */
      asm_fprintf (stream, "\tnop\n");
      return;
    }

#ifdef FUNCTION_EXTRA_EPILOGUE
  FUNCTION_EXTRA_EPILOGUE (stream, size);
#endif
  nregs = 0;  fmask = 0; fpoffset = 0;
#ifdef SUPPORT_SUN_FPA
  for (regno = 24 ; regno < 56 ; regno++)
    if (regs_ever_live[regno] && ! call_used_regs[regno])
      nregs++;
  fpoffset = nregs * 8;
#endif
  nregs = 0;
  if (TARGET_68881)
    {
      for (regno = 16; regno < 24; regno++)
	if (regs_ever_live[regno] && ! call_used_regs[regno])
	  {
	    nregs++;
	    fmask |= 1 << (23 - regno);
	  }
    }
  foffset = fpoffset + nregs * 12;
  nregs = 0;  mask = 0;
  if (frame_pointer_needed)
    regs_ever_live[FRAME_POINTER_REGNUM] = 0;
  for (regno = 0; regno < 16; regno++)
    if (regs_ever_live[regno] && ! call_used_regs[regno])
      {
        nregs++;
	mask |= 1 << regno;
      }
  if (flag_pic && current_function_uses_pic_offset_table)
    {
      nregs++;
      mask |= 1 << PIC_OFFSET_TABLE_REGNUM;
    }
  offset = foffset + nregs * 4;
  /* FIXME : leaf_function_p below is too strong.
     What we really need to know there is if there could be pending
     stack adjustment needed at that point.  */
  restore_from_sp = ! frame_pointer_needed
	     || (! current_function_calls_alloca && leaf_function_p ());
  if (offset + fsize >= 0x8000
      && ! restore_from_sp
      && (mask || fmask || fpoffset))
    {
#ifdef MOTOROLA
      asm_fprintf (stream, "\t%Omove.l %0I%d,%Ra1\n", -fsize);
#else
      asm_fprintf (stream, "\tmovel %0I%d,%Ra1\n", -fsize);
#endif
      fsize = 0, big = 1;
    }
  if (TARGET_5200 || nregs <= 2)
    {
      /* Restore each separately in the same order moveml does.
         Using two movel instructions instead of a single moveml
         is about 15% faster for the 68020 and 68030 at no expense
         in code size.  */

      int i;

      /* Undo the work from above.  */
      for (i = 0; i< 16; i++)
        if (mask & (1 << i))
          {
            if (big)
	      {
#ifdef MOTOROLA
		asm_fprintf (stream, "\t%Omove.l -%d(%s,%Ra1.l),%s\n",
			     offset + fsize,
			     reg_names[FRAME_POINTER_REGNUM],
			     reg_names[i]);
#else
		asm_fprintf (stream, "\tmovel %s@(-%d,%Ra1:l),%s\n",
			     reg_names[FRAME_POINTER_REGNUM],
			     offset + fsize, reg_names[i]);
#endif
	      }
            else if (restore_from_sp)
	      {
#ifdef MOTOROLA
		asm_fprintf (stream, "\t%Omove.l (%Rsp)+,%s\n",
			     reg_names[i]);
#else
		asm_fprintf (stream, "\tmovel %Rsp@+,%s\n",
			     reg_names[i]);
#endif
	      }
            else
	      {
#ifdef MOTOROLA
		asm_fprintf (stream, "\t%Omove.l -%d(%s),%s\n",
			     offset + fsize,
			     reg_names[FRAME_POINTER_REGNUM],
			     reg_names[i]);
#else
		asm_fprintf (stream, "\tmovel %s@(-%d),%s\n",
			     reg_names[FRAME_POINTER_REGNUM],
			     offset + fsize, reg_names[i]);
#endif
	      }
            offset = offset - 4;
          }
    }
  else if (mask)
    {
      if (big)
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tmovm.l -%d(%s,%Ra1.l),%0I0x%x\n",
		       offset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       mask);
#else
	  asm_fprintf (stream, "\tmoveml %s@(-%d,%Ra1:l),%0I0x%x\n",
		       reg_names[FRAME_POINTER_REGNUM],
		       offset + fsize, mask);
#endif
	}
      else if (restore_from_sp)
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tmovm.l (%Rsp)+,%0I0x%x\n", mask);
#else
	  asm_fprintf (stream, "\tmoveml %Rsp@+,%0I0x%x\n", mask);
#endif
	}
      else
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tmovm.l -%d(%s),%0I0x%x\n",
		       offset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       mask);
#else
	  asm_fprintf (stream, "\tmoveml %s@(-%d),%0I0x%x\n",
		       reg_names[FRAME_POINTER_REGNUM],
		       offset + fsize, mask);
#endif
	}
    }
  if (fmask)
    {
      if (big)
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tfmovm -%d(%s,%Ra1.l),%0I0x%x\n",
		       foffset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       fmask);
#else
	  asm_fprintf (stream, "\tfmovem %s@(-%d,%Ra1:l),%0I0x%x\n",
		       reg_names[FRAME_POINTER_REGNUM],
		       foffset + fsize, fmask);
#endif
	}
      else if (restore_from_sp)
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tfmovm (%Rsp)+,%0I0x%x\n", fmask);
#else
	  asm_fprintf (stream, "\tfmovem %Rsp@+,%0I0x%x\n", fmask);
#endif
	}
      else
	{
#ifdef MOTOROLA
	  asm_fprintf (stream, "\tfmovm -%d(%s),%0I0x%x\n",
		       foffset + fsize,
		       reg_names[FRAME_POINTER_REGNUM],
		       fmask);
#else
	  asm_fprintf (stream, "\tfmovem %s@(-%d),%0I0x%x\n",
		       reg_names[FRAME_POINTER_REGNUM],
		       foffset + fsize, fmask);
#endif
	}
    }
  if (fpoffset != 0)
    for (regno = 55; regno >= 24; regno--)
      if (regs_ever_live[regno] && ! call_used_regs[regno])
        {
	  if (big)
	    {
#ifdef MOTOROLA
	      asm_fprintf (stream, "\tfpmovd -%d(%s,%Ra1.l), %s\n",
			   fpoffset + fsize,
			   reg_names[FRAME_POINTER_REGNUM],
			   reg_names[regno]);
#else
	      asm_fprintf (stream, "\tfpmoved %s@(-%d,%Ra1:l), %s\n",
			   reg_names[FRAME_POINTER_REGNUM],
			   fpoffset + fsize, reg_names[regno]);
#endif
	    }
	  else if (restore_from_sp)
	    {
#ifdef MOTOROLA
	      asm_fprintf (stream, "\tfpmovd (%Rsp)+,%s\n",
			   reg_names[regno]);
#else
	      asm_fprintf (stream, "\tfpmoved %Rsp@+, %s\n",
			   reg_names[regno]);
#endif
	    }
	  else
	    {
#ifdef MOTOROLA
	      asm_fprintf (stream, "\tfpmovd -%d(%s), %s\n",
			   fpoffset + fsize,
			   reg_names[FRAME_POINTER_REGNUM],
			   reg_names[regno]);
#else
	      asm_fprintf (stream, "\tfpmoved %s@(-%d), %s\n",
			   reg_names[FRAME_POINTER_REGNUM],
			   fpoffset + fsize, reg_names[regno]);
#endif
	    }
	  fpoffset -= 8;
	}
  if (frame_pointer_needed)
    fprintf (stream, "\tunlk %s\n",
	     reg_names[FRAME_POINTER_REGNUM]);
  else if (fsize)
    {
#ifndef NO_ADDSUB_Q
      if (fsize + 4 <= 8) 
	{
	  if (!TARGET_5200)
	    {
#ifdef MOTOROLA
	      asm_fprintf (stream, "\taddq.w %0I%d,%Rsp\n", fsize + 4);
#else
	      asm_fprintf (stream, "\taddqw %0I%d,%Rsp\n", fsize + 4);
#endif
	    }
	  else
	    {
#ifdef MOTOROLA
	      asm_fprintf (stream, "\taddq.l %0I%d,%Rsp\n", fsize + 4);
#else
	      asm_fprintf (stream, "\taddql %0I%d,%Rsp\n", fsize + 4);
#endif
	    }
	}
      else if (fsize + 4 <= 16 && TARGET_CPU32)
	{
	  /* On the CPU32 it is faster to use two addqw instructions to
	     add a small integer (8 < N <= 16) to a register.  */
	  /* asm_fprintf() cannot handle %.  */
#ifdef MOTOROLA
	  asm_fprintf (stream, "\taddq.w %0I8,%Rsp\n\taddq.w %0I%d,%Rsp\n",
		       fsize + 4 - 8);