i386.c

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  if (mode != VOIDmode && mode != GET_MODE (op))
    return 0;

  code = GET_CODE (op);
  if (GET_RTX_CLASS (code) != '<')
    return 0;

  return (code != GT && code != LE);
}

int
ix86_logical_operator (op, mode)
     register rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  return GET_CODE (op) == AND || GET_CODE (op) == IOR || GET_CODE (op) == XOR;
}


/* Returns 1 if OP contains a symbol reference */

int
symbolic_reference_mentioned_p (op)
     rtx op;
{
  register char *fmt;
  register int i;

  if (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == LABEL_REF)
    return 1;

  fmt = GET_RTX_FORMAT (GET_CODE (op));
  for (i = GET_RTX_LENGTH (GET_CODE (op)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'E')
	{
	  register int j;

	  for (j = XVECLEN (op, i) - 1; j >= 0; j--)
	    if (symbolic_reference_mentioned_p (XVECEXP (op, i, j)))
	      return 1;
	}

      else if (fmt[i] == 'e' && symbolic_reference_mentioned_p (XEXP (op, i)))
	return 1;
    }

  return 0;
}

/* Attempt to expand a binary operator.  Make the expansion closer to the
   actual machine, then just general_operand, which will allow 3 separate
   memory references (one output, two input) in a single insn.  Return
   whether the insn fails, or succeeds.  */

int
ix86_expand_binary_operator (code, mode, operands)
     enum rtx_code code;
     enum machine_mode mode;
     rtx operands[];
{
  int modified;

  /* Recognize <var1> = <value> <op> <var1> for commutative operators */
  if (GET_RTX_CLASS (code) == 'c'
      && (rtx_equal_p (operands[0], operands[2])
	  || immediate_operand (operands[1], mode)))
    {
      rtx temp = operands[1];
      operands[1] = operands[2];
      operands[2] = temp;
    }

  /* If optimizing, copy to regs to improve CSE */
  if (TARGET_PSEUDO && optimize
      && ((reload_in_progress | reload_completed) == 0))
    {
      if (GET_CODE (operands[1]) == MEM
	  && ! rtx_equal_p (operands[0], operands[1]))
	operands[1] = force_reg (GET_MODE (operands[1]), operands[1]);

      if (GET_CODE (operands[2]) == MEM)
	operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);

      if (GET_CODE (operands[1]) == CONST_INT && code == MINUS)
	{
	  rtx temp = gen_reg_rtx (GET_MODE (operands[0]));

	  emit_move_insn (temp, operands[1]);
	  operands[1] = temp;
	  return TRUE;
	}
    }

  if (!ix86_binary_operator_ok (code, mode, operands))
    {
      /* If not optimizing, try to make a valid insn (optimize code
	 previously did this above to improve chances of CSE) */

      if ((! TARGET_PSEUDO || !optimize)
	  && ((reload_in_progress | reload_completed) == 0)
	  && (GET_CODE (operands[1]) == MEM || GET_CODE (operands[2]) == MEM))
	{
	  modified = FALSE;
	  if (GET_CODE (operands[1]) == MEM
	      && ! rtx_equal_p (operands[0], operands[1]))
	    {
	      operands[1] = force_reg (GET_MODE (operands[1]), operands[1]);
	      modified = TRUE;
	    }

	  if (GET_CODE (operands[2]) == MEM)
	    {
	      operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);
	      modified = TRUE;
	    }

	  if (GET_CODE (operands[1]) == CONST_INT && code == MINUS)
	    {
	      rtx temp = gen_reg_rtx (GET_MODE (operands[0]));

	      emit_move_insn (temp, operands[1]);
	      operands[1] = temp;
	      return TRUE;
	    }

	  if (modified && ! ix86_binary_operator_ok (code, mode, operands))
	    return FALSE;
	}
      else
	return FALSE;
    }

  return TRUE;
}

/* Return TRUE or FALSE depending on whether the binary operator meets the
   appropriate constraints.  */

int
ix86_binary_operator_ok (code, mode, operands)
     enum rtx_code code;
     enum machine_mode mode ATTRIBUTE_UNUSED;
     rtx operands[3];
{
  return (GET_CODE (operands[1]) != MEM || GET_CODE (operands[2]) != MEM)
    && (GET_CODE (operands[1]) != CONST_INT || GET_RTX_CLASS (code) == 'c');
}

/* Attempt to expand a unary operator.  Make the expansion closer to the
   actual machine, then just general_operand, which will allow 2 separate
   memory references (one output, one input) in a single insn.  Return
   whether the insn fails, or succeeds.  */

int
ix86_expand_unary_operator (code, mode, operands)
     enum rtx_code code;
     enum machine_mode mode;
     rtx operands[];
{
  /* If optimizing, copy to regs to improve CSE */
  if (TARGET_PSEUDO
      && optimize
      && ((reload_in_progress | reload_completed) == 0)
      && GET_CODE (operands[1]) == MEM)
    operands[1] = force_reg (GET_MODE (operands[1]), operands[1]);

  if (! ix86_unary_operator_ok (code, mode, operands))
    {
      if ((! TARGET_PSEUDO || optimize == 0)
	  && ((reload_in_progress | reload_completed) == 0)
	  && GET_CODE (operands[1]) == MEM)
	{
	  operands[1] = force_reg (GET_MODE (operands[1]), operands[1]);
	  if (! ix86_unary_operator_ok (code, mode, operands))
	    return FALSE;
	}
      else
	return FALSE;
    }

  return TRUE;
}

/* Return TRUE or FALSE depending on whether the unary operator meets the
   appropriate constraints.  */

int
ix86_unary_operator_ok (code, mode, operands)
     enum rtx_code code ATTRIBUTE_UNUSED;
     enum machine_mode mode ATTRIBUTE_UNUSED;
     rtx operands[2] ATTRIBUTE_UNUSED;
{
  return TRUE;
}

static rtx pic_label_rtx;
static char pic_label_name [256];
static int pic_label_no = 0;

/* This function generates code for -fpic that loads %ebx with
   the return address of the caller and then returns.  */

void
asm_output_function_prefix (file, name)
     FILE *file;
     char *name ATTRIBUTE_UNUSED;
{
  rtx xops[2];
  int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
				  || current_function_uses_const_pool);
  xops[0] = pic_offset_table_rtx;
  xops[1] = stack_pointer_rtx;

  /* Deep branch prediction favors having a return for every call. */
  if (pic_reg_used && TARGET_DEEP_BRANCH_PREDICTION)
    {
      tree prologue_node;

      if (pic_label_rtx == 0)
	{
	  pic_label_rtx = gen_label_rtx ();
	  ASM_GENERATE_INTERNAL_LABEL (pic_label_name, "LPR", pic_label_no++);
	  LABEL_NAME (pic_label_rtx) = pic_label_name;
	}

      prologue_node = make_node (FUNCTION_DECL);
      DECL_RESULT (prologue_node) = 0;

      /* This used to call ASM_DECLARE_FUNCTION_NAME() but since it's an
	 internal (non-global) label that's being emitted, it didn't make
	 sense to have .type information for local labels.   This caused
	 the SCO OpenServer 5.0.4 ELF assembler grief (why are you giving
  	 me debug info for a label that you're declaring non-global?) this
	 was changed to call ASM_OUTPUT_LABEL() instead. */


      ASM_OUTPUT_LABEL (file, pic_label_name); 
      output_asm_insn ("movl (%1),%0", xops);
      output_asm_insn ("ret", xops);
    }
}

/* Generate the assembly code for function entry.
   FILE is an stdio stream to output the code to.
   SIZE is an int: how many units of temporary storage to allocate. */

void
function_prologue (file, size)
     FILE *file ATTRIBUTE_UNUSED;
     int size ATTRIBUTE_UNUSED;
{
  if (TARGET_SCHEDULE_PROLOGUE)
    {
      pic_label_rtx = 0;
      return;
    }

  ix86_prologue (0);
}

/* Expand the prologue into a bunch of separate insns. */

void
ix86_expand_prologue ()
{
  if (! TARGET_SCHEDULE_PROLOGUE)
      return;

  ix86_prologue (1);
}

void
load_pic_register (do_rtl)
     int do_rtl;
{
  rtx xops[4];

  if (TARGET_DEEP_BRANCH_PREDICTION)
    {
      xops[0] = pic_offset_table_rtx;
      if (pic_label_rtx == 0)
	{
	  pic_label_rtx = gen_label_rtx ();
	  ASM_GENERATE_INTERNAL_LABEL (pic_label_name, "LPR", pic_label_no++);
	  LABEL_NAME (pic_label_rtx) = pic_label_name;
	}

      xops[1] = gen_rtx_MEM (QImode,
			 gen_rtx (SYMBOL_REF, Pmode,
				  LABEL_NAME (pic_label_rtx)));

      if (do_rtl)
	{
	  emit_insn (gen_prologue_get_pc (xops[0], xops[1]));
	  emit_insn (gen_prologue_set_got (xops[0],
#ifdef YES_UNDERSCORES
					   gen_rtx_SYMBOL_REF (Pmode,
  					            "$__GLOBAL_OFFSET_TABLE_"),
#else
					   gen_rtx_SYMBOL_REF (Pmode,
					            "$_GLOBAL_OFFSET_TABLE_"),
#endif
					   xops[1]));
	}
      else
	{
	  output_asm_insn (AS1 (call,%X1), xops);
	  output_asm_insn ("addl $%__GLOBAL_OFFSET_TABLE_,%0", xops);
	  pic_label_rtx = 0;
	}
    }

  else
    {
      xops[0] = pic_offset_table_rtx;
      xops[1] = gen_label_rtx ();

      if (do_rtl)
	{
	  /* We can't put a raw CODE_LABEL into the RTL, and we can't emit
	     a new CODE_LABEL after reload, so we need a single pattern to
	     emit the 3 necessary instructions.  */
	  emit_insn (gen_prologue_get_pc_and_set_got (xops[0]));
	}
      else
	{
	  output_asm_insn (AS1 (call,%P1), xops);
	  ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "L",
				     CODE_LABEL_NUMBER (xops[1]));
	  output_asm_insn (AS1 (pop%L0,%0), xops);
	  output_asm_insn ("addl $%__GLOBAL_OFFSET_TABLE_+[.-%P1],%0", xops);
	}
    }

  /* When -fpic, we must emit a scheduling barrier, so that the instruction
     that restores %ebx (which is PIC_OFFSET_TABLE_REGNUM), does not get
     moved before any instruction which implicitly uses the got.   */

  if (do_rtl)
    emit_insn (gen_blockage ());
}

/* Compute the size of local storage taking into consideration the
   desired stack alignment which is to be maintained.  Also determine
   the number of registers saved below the local storage.  */

HOST_WIDE_INT
ix86_compute_frame_size (size, nregs_on_stack)
     HOST_WIDE_INT size;
     int *nregs_on_stack;
{
  int limit;
  int nregs;
  int regno;
  int padding;
  int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
				  || current_function_uses_const_pool);
  HOST_WIDE_INT total_size;

  limit = frame_pointer_needed
	  ? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM;

  nregs = 0;

  for (regno = limit - 1; regno >= 0; regno--)
    if ((regs_ever_live[regno] && ! call_used_regs[regno])
	|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
      nregs++;

  padding = 0;
  total_size = size + (nregs * UNITS_PER_WORD);

#ifdef PREFERRED_STACK_BOUNDARY
  {
    int offset;
    int preferred_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;

    offset = 4;
    if (frame_pointer_needed)
      offset += UNITS_PER_WORD;

    total_size += offset;
    
    padding = ((total_size + preferred_alignment - 1)
	       & -preferred_alignment) - total_size;

    if (padding < (((offset + preferred_alignment - 1)
		    & -preferred_alignment) - offset))
      padding += preferred_alignment;

    /* Don't bother aligning the stack of a leaf function
       which doesn't allocate any stack slots.  */
    if (size == 0 && current_function_is_leaf)
      padding = 0;
  }
#endif

  if (nregs_on_stack)
    *nregs_on_stack = nregs;

  return size + padding;
}

static void
ix86_prologue (do_rtl)
     int do_rtl;
{
  register int regno;
  int limit;
  rtx xops[4];
  int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
				  || current_function_uses_const_pool);
  HOST_WIDE_INT tsize = ix86_compute_frame_size (get_frame_size (), (int *)0);
  rtx insn;
  int cfa_offset = INCOMING_FRAME_SP_OFFSET, cfa_store_offset = cfa_offset;

  xops[0] = stack_pointer_rtx;
  xops[1] = frame_pointer_rtx;
  xops[2] = GEN_INT (tsize);

  if (frame_pointer_needed)
    {
      if (do_rtl)
	{
	  insn = emit_insn (gen_rtx (SET, VOIDmode,
				     gen_rtx_MEM (SImode,
					      gen_rtx (PRE_DEC, SImode,
						       stack_pointer_rtx)),
				     frame_pointer_rtx));

	  RTX_FRAME_RELATED_P (insn) = 1;
	  insn = emit_move_insn (xops[1], xops[0]);
	  RTX_FRAME_RELATED_P (insn) = 1;
	}

      else
	{
	  output_asm_insn ("push%L1 %1", xops);
#ifdef INCOMING_RETURN_ADDR_RTX
 	  if (dwarf2out_do_frame ())
 	    {
 	      char *l = dwarf2out_cfi_label ();

 	      cfa_store_offset += 4;
 	      cfa_offset = cfa_store_offset;
 	      dwarf2out_def_cfa (l, STACK_POINTER_REGNUM, cfa_offset);
 	      dwarf2out_reg_save (l, FRAME_POINTER_REGNUM, - cfa_store_offset);
 	    }
#endif

	  output_asm_insn (AS2 (mov%L0,%0,%1), xops);
#ifdef INCOMING_RETURN_ADDR_RTX
 	  if (dwarf2out_do_frame ())
 	    dwarf2out_def_cfa ("", FRAME_POINTER_REGNUM, cfa_offset);
#endif
	}
    }

  if (tsize == 0)
    ;
  else if (! TARGET_STACK_PROBE || tsize < CHECK_STACK_LIMIT)
    {
      if (do_rtl)
	{
	  insn = emit_insn (gen_prologue_set_stack_ptr (xops[2]));
	  RTX_FRAME_RELATED_P (insn) = 1;
	}
      else
	{
	  output_asm_insn (AS2 (sub%L0,%2,%0), xops);
#ifdef INCOMING_RETURN_ADDR_RTX
 	  if (dwarf2out_do_frame ())
 	    {
 	      cfa_store_offset += tsize;
 	      if (! frame_pointer_needed)
 		{