Beispiel #1
0
void
do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
			 machine_mode mode, rtx size,
			 rtx_code_label *if_false_label,
			 rtx_code_label *if_true_label, int prob)
{
  rtx tem;
  rtx_code_label *dummy_label = NULL;

  /* Reverse the comparison if that is safe and we want to jump if it is
     false.  Also convert to the reverse comparison if the target can
     implement it.  */
  if ((! if_true_label
       || ! can_compare_p (code, mode, ccp_jump))
      && (! FLOAT_MODE_P (mode)
	  || code == ORDERED || code == UNORDERED
	  || (! HONOR_NANS (mode) && (code == LTGT || code == UNEQ))
	  || (! HONOR_SNANS (mode) && (code == EQ || code == NE))))
    {
      enum rtx_code rcode;
      if (FLOAT_MODE_P (mode))
        rcode = reverse_condition_maybe_unordered (code);
      else
        rcode = reverse_condition (code);

      /* Canonicalize to UNORDERED for the libcall.  */
      if (can_compare_p (rcode, mode, ccp_jump)
	  || (code == ORDERED && ! can_compare_p (ORDERED, mode, ccp_jump)))
	{
	  std::swap (if_true_label, if_false_label);
	  code = rcode;
	  prob = inv (prob);
	}
    }

  /* If one operand is constant, make it the second one.  Only do this
     if the other operand is not constant as well.  */

  if (swap_commutative_operands_p (op0, op1))
    {
      std::swap (op0, op1);
      code = swap_condition (code);
    }

  do_pending_stack_adjust ();

  code = unsignedp ? unsigned_condition (code) : code;
  if (0 != (tem = simplify_relational_operation (code, mode, VOIDmode,
						 op0, op1)))
    {
      if (CONSTANT_P (tem))
	{
	  rtx_code_label *label = (tem == const0_rtx
				   || tem == CONST0_RTX (mode))
					? if_false_label : if_true_label;
	  if (label)
	    emit_jump (label);
	  return;
	}

      code = GET_CODE (tem);
      mode = GET_MODE (tem);
      op0 = XEXP (tem, 0);
      op1 = XEXP (tem, 1);
      unsignedp = (code == GTU || code == LTU || code == GEU || code == LEU);
    }

  if (! if_true_label)
    dummy_label = if_true_label = gen_label_rtx ();

  if (GET_MODE_CLASS (mode) == MODE_INT
      && ! can_compare_p (code, mode, ccp_jump))
    {
      switch (code)
	{
	case LTU:
	  do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
					if_false_label, if_true_label, prob);
	  break;

	case LEU:
	  do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
					if_true_label, if_false_label,
					inv (prob));
	  break;

	case GTU:
	  do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
					if_false_label, if_true_label, prob);
	  break;

	case GEU:
	  do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
					if_true_label, if_false_label,
					inv (prob));
	  break;

	case LT:
	  do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
					if_false_label, if_true_label, prob);
	  break;

	case LE:
	  do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
					if_true_label, if_false_label,
					inv (prob));
	  break;

	case GT:
	  do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
					if_false_label, if_true_label, prob);
	  break;

	case GE:
	  do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
					if_true_label, if_false_label,
					inv (prob));
	  break;

	case EQ:
	  do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
					 if_true_label, prob);
	  break;

	case NE:
	  do_jump_by_parts_equality_rtx (mode, op0, op1, if_true_label,
					 if_false_label, inv (prob));
	  break;

	default:
	  gcc_unreachable ();
	}
    }
  else
    {
      if (SCALAR_FLOAT_MODE_P (mode)
	  && ! can_compare_p (code, mode, ccp_jump)
	  && can_compare_p (swap_condition (code), mode, ccp_jump))
	{
	  code = swap_condition (code);
	  std::swap (op0, op1);
	}
      else if (SCALAR_FLOAT_MODE_P (mode)
	       && ! can_compare_p (code, mode, ccp_jump)
	       /* Never split ORDERED and UNORDERED.
		  These must be implemented.  */
	       && (code != ORDERED && code != UNORDERED)
               /* Split a floating-point comparison if
		  we can jump on other conditions...  */
	       && (have_insn_for (COMPARE, mode)
	           /* ... or if there is no libcall for it.  */
	           || code_to_optab (code) == unknown_optab))
        {
	  enum rtx_code first_code;
	  bool and_them = split_comparison (code, mode, &first_code, &code);

	  /* If there are no NaNs, the first comparison should always fall
	     through.  */
	  if (!HONOR_NANS (mode))
	    gcc_assert (first_code == (and_them ? ORDERED : UNORDERED));

	  else
	    {
	      int first_prob = prob;
	      if (first_code == UNORDERED)
		first_prob = REG_BR_PROB_BASE / 100;
	      else if (first_code == ORDERED)
		first_prob = REG_BR_PROB_BASE - REG_BR_PROB_BASE / 100;
	      if (and_them)
		{
		  rtx_code_label *dest_label;
		  /* If we only jump if true, just bypass the second jump.  */
		  if (! if_false_label)
		    {
		      if (! dummy_label)
		        dummy_label = gen_label_rtx ();
		      dest_label = dummy_label;
		    }
		  else
		    dest_label = if_false_label;
                  do_compare_rtx_and_jump (op0, op1, first_code, unsignedp, mode,
					   size, dest_label, NULL, first_prob);
		}
              else
                do_compare_rtx_and_jump (op0, op1, first_code, unsignedp, mode,
					 size, NULL, if_true_label, first_prob);
	    }
	}

      emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
			       if_true_label, prob);
    }

  if (if_false_label)
    emit_jump (if_false_label);
  if (dummy_label)
    emit_label (dummy_label);
}
Beispiel #2
0
static bool
ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
		   basic_block outer_cond_bb, bool outer_inv, bool result_inv)
{
  gimple_stmt_iterator gsi;
  gimple inner_cond, outer_cond;
  tree name1, name2, bit1, bit2, bits1, bits2;

  inner_cond = last_stmt (inner_cond_bb);
  if (!inner_cond
      || gimple_code (inner_cond) != GIMPLE_COND)
    return false;

  outer_cond = last_stmt (outer_cond_bb);
  if (!outer_cond
      || gimple_code (outer_cond) != GIMPLE_COND)
    return false;

  /* See if we test a single bit of the same name in both tests.  In
     that case remove the outer test, merging both else edges,
     and change the inner one to test for
     name & (bit1 | bit2) == (bit1 | bit2).  */
  if (recognize_single_bit_test (inner_cond, &name1, &bit1, inner_inv)
      && recognize_single_bit_test (outer_cond, &name2, &bit2, outer_inv)
      && name1 == name2)
    {
      tree t, t2;

      /* Do it.  */
      gsi = gsi_for_stmt (inner_cond);
      t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (name1),
		       build_int_cst (TREE_TYPE (name1), 1), bit1);
      t2 = fold_build2 (LSHIFT_EXPR, TREE_TYPE (name1),
		        build_int_cst (TREE_TYPE (name1), 1), bit2);
      t = fold_build2 (BIT_IOR_EXPR, TREE_TYPE (name1), t, t2);
      t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
				    true, GSI_SAME_STMT);
      t2 = fold_build2 (BIT_AND_EXPR, TREE_TYPE (name1), name1, t);
      t2 = force_gimple_operand_gsi (&gsi, t2, true, NULL_TREE,
				     true, GSI_SAME_STMT);
      t = fold_build2 (result_inv ? NE_EXPR : EQ_EXPR,
		       boolean_type_node, t2, t);
      t = canonicalize_cond_expr_cond (t);
      if (!t)
	return false;
      gimple_cond_set_condition_from_tree (inner_cond, t);
      update_stmt (inner_cond);

      /* Leave CFG optimization to cfg_cleanup.  */
      gimple_cond_set_condition_from_tree (outer_cond,
	outer_inv ? boolean_false_node : boolean_true_node);
      update_stmt (outer_cond);

      if (dump_file)
	{
	  fprintf (dump_file, "optimizing double bit test to ");
	  print_generic_expr (dump_file, name1, 0);
	  fprintf (dump_file, " & T == T\nwith temporary T = (1 << ");
	  print_generic_expr (dump_file, bit1, 0);
	  fprintf (dump_file, ") | (1 << ");
	  print_generic_expr (dump_file, bit2, 0);
	  fprintf (dump_file, ")\n");
	}

      return true;
    }

  /* See if we have two bit tests of the same name in both tests.
     In that case remove the outer test and change the inner one to
     test for name & (bits1 | bits2) != 0.  */
  else if (recognize_bits_test (inner_cond, &name1, &bits1, !inner_inv)
      && recognize_bits_test (outer_cond, &name2, &bits2, !outer_inv))
    {
      gimple_stmt_iterator gsi;
      tree t;

      /* Find the common name which is bit-tested.  */
      if (name1 == name2)
	;
      else if (bits1 == bits2)
	{
	  t = name2;
	  name2 = bits2;
	  bits2 = t;
	  t = name1;
	  name1 = bits1;
	  bits1 = t;
	}
      else if (name1 == bits2)
	{
	  t = name2;
	  name2 = bits2;
	  bits2 = t;
	}
      else if (bits1 == name2)
	{
	  t = name1;
	  name1 = bits1;
	  bits1 = t;
	}
      else
	return false;

      /* As we strip non-widening conversions in finding a common
         name that is tested make sure to end up with an integral
	 type for building the bit operations.  */
      if (TYPE_PRECISION (TREE_TYPE (bits1))
	  >= TYPE_PRECISION (TREE_TYPE (bits2)))
	{
	  bits1 = fold_convert (unsigned_type_for (TREE_TYPE (bits1)), bits1);
	  name1 = fold_convert (TREE_TYPE (bits1), name1);
	  bits2 = fold_convert (unsigned_type_for (TREE_TYPE (bits2)), bits2);
	  bits2 = fold_convert (TREE_TYPE (bits1), bits2);
	}
      else
	{
	  bits2 = fold_convert (unsigned_type_for (TREE_TYPE (bits2)), bits2);
	  name1 = fold_convert (TREE_TYPE (bits2), name1);
	  bits1 = fold_convert (unsigned_type_for (TREE_TYPE (bits1)), bits1);
	  bits1 = fold_convert (TREE_TYPE (bits2), bits1);
	}

      /* Do it.  */
      gsi = gsi_for_stmt (inner_cond);
      t = fold_build2 (BIT_IOR_EXPR, TREE_TYPE (name1), bits1, bits2);
      t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
				    true, GSI_SAME_STMT);
      t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (name1), name1, t);
      t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
				    true, GSI_SAME_STMT);
      t = fold_build2 (result_inv ? NE_EXPR : EQ_EXPR, boolean_type_node, t,
		       build_int_cst (TREE_TYPE (t), 0));
      t = canonicalize_cond_expr_cond (t);
      if (!t)
	return false;
      gimple_cond_set_condition_from_tree (inner_cond, t);
      update_stmt (inner_cond);

      /* Leave CFG optimization to cfg_cleanup.  */
      gimple_cond_set_condition_from_tree (outer_cond,
	outer_inv ? boolean_false_node : boolean_true_node);
      update_stmt (outer_cond);

      if (dump_file)
	{
	  fprintf (dump_file, "optimizing bits or bits test to ");
	  print_generic_expr (dump_file, name1, 0);
	  fprintf (dump_file, " & T != 0\nwith temporary T = ");
	  print_generic_expr (dump_file, bits1, 0);
	  fprintf (dump_file, " | ");
	  print_generic_expr (dump_file, bits2, 0);
	  fprintf (dump_file, "\n");
	}

      return true;
    }

  /* See if we have two comparisons that we can merge into one.  */
  else if (TREE_CODE_CLASS (gimple_cond_code (inner_cond)) == tcc_comparison
	   && TREE_CODE_CLASS (gimple_cond_code (outer_cond)) == tcc_comparison)
    {
      tree t;
      enum tree_code inner_cond_code = gimple_cond_code (inner_cond);
      enum tree_code outer_cond_code = gimple_cond_code (outer_cond);

      /* Invert comparisons if necessary (and possible).  */
      if (inner_inv)
	inner_cond_code = invert_tree_comparison (inner_cond_code,
	  HONOR_NANS (TYPE_MODE (TREE_TYPE (gimple_cond_lhs (inner_cond)))));
      if (inner_cond_code == ERROR_MARK)
	return false;
      if (outer_inv)
	outer_cond_code = invert_tree_comparison (outer_cond_code,
	  HONOR_NANS (TYPE_MODE (TREE_TYPE (gimple_cond_lhs (outer_cond)))));
      if (outer_cond_code == ERROR_MARK)
	return false;
      /* Don't return false so fast, try maybe_fold_or_comparisons?  */

      if (!(t = maybe_fold_and_comparisons (inner_cond_code,
					    gimple_cond_lhs (inner_cond),
					    gimple_cond_rhs (inner_cond),
					    outer_cond_code,
					    gimple_cond_lhs (outer_cond),
					    gimple_cond_rhs (outer_cond))))
	{
	  tree t1, t2;
	  gimple_stmt_iterator gsi;
	  if (!LOGICAL_OP_NON_SHORT_CIRCUIT)
	    return false;
	  /* Only do this optimization if the inner bb contains only the conditional. */
	  if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
	    return false;
	  t1 = fold_build2_loc (gimple_location (inner_cond),
				inner_cond_code,
				boolean_type_node,
				gimple_cond_lhs (inner_cond),
				gimple_cond_rhs (inner_cond));
	  t2 = fold_build2_loc (gimple_location (outer_cond),
				outer_cond_code,
				boolean_type_node,
				gimple_cond_lhs (outer_cond),
				gimple_cond_rhs (outer_cond));
	  t = fold_build2_loc (gimple_location (inner_cond), 
			       TRUTH_AND_EXPR, boolean_type_node, t1, t2);
	  if (result_inv)
	    {
	      t = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (t), t);
	      result_inv = false;
	    }
	  gsi = gsi_for_stmt (inner_cond);
	  t = force_gimple_operand_gsi_1 (&gsi, t, is_gimple_condexpr, NULL, true,
					  GSI_SAME_STMT);
        }
      if (result_inv)
	t = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (t), t);
      t = canonicalize_cond_expr_cond (t);
      if (!t)
	return false;
      gimple_cond_set_condition_from_tree (inner_cond, t);
      update_stmt (inner_cond);

      /* Leave CFG optimization to cfg_cleanup.  */
      gimple_cond_set_condition_from_tree (outer_cond,
	outer_inv ? boolean_false_node : boolean_true_node);
      update_stmt (outer_cond);

      if (dump_file)
	{
	  fprintf (dump_file, "optimizing two comparisons to ");
	  print_generic_expr (dump_file, t, 0);
	  fprintf (dump_file, "\n");
	}

      return true;
    }

  return false;
}