Hi,
On Mon, 10 Oct 2011, Kai Tietz wrote:
> To ensure that we use simple_operand_p in all cases, beside for
> branching AND/OR chains, in same way as before, I added to this function
> an additional argument, by which the looking into comparisons can be
> activated.
Better make it a separate function the first tests your new conditions,
and then calls simple_operand_p.
> +fold_truth_andor_1 (location_t loc, enum tree_code code, tree truth_type,
> + tree lhs, tree rhs)
> {
> /* If this is the "or" of two comparisons, we can do something if
> the comparisons are NE_EXPR. If this is the "and", we can do something
> @@ -5149,13 +5176,6 @@ fold_truthop (location_t loc, enum tree_
> build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
> ll_arg, rl_arg),
> build_int_cst (TREE_TYPE (ll_arg), 0));
> -
> - if (LOGICAL_OP_NON_SHORT_CIRCUIT)
> - {
> - if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
> - return build2_loc (loc, code, truth_type, lhs, rhs);
> - return NULL_TREE;
> - }
Why do you remove this hunk? Shouldn't you instead move the hunk you
added to fold_truth_andor() here. I realize this needs some TLC to
fold_truth_andor_1, because right now it early-outs for non-comparisons,
but it seems the better place. I.e. somehow move the below code into the
above branch, with the associated diddling on fold_truth_andor_1 that it
gets called.
> + if ((code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
> + && (BRANCH_COST (optimize_function_for_speed_p (cfun),
> + false) >= 2)
> + && !TREE_SIDE_EFFECTS (arg1)
> + && LOGICAL_OP_NON_SHORT_CIRCUIT
> + && simple_operand_p (arg1, true))
> + {
> + enum tree_code ncode = (code == TRUTH_ANDIF_EXPR ? TRUTH_AND_EXPR
> + : TRUTH_OR_EXPR);
> +
> + /* We don't want to pack more then two leafs to an non-IF
Missing continuation of the sentence?
> + If tree-code of left-hand operand isn't an AND/OR-IF code and not
> + equal to CODE, then we don't want to add right-hand operand.
> + If the inner right-hand side of left-hand operand has side-effects,
> + or isn't simple, then we can't add to it, as otherwise we might
> + destroy if-sequence. */
> + if (TREE_CODE (arg0) == code
> + /* Needed for sequence points to handle trappings, and
> + side-effects. */
> + && !TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))
> + && simple_operand_p (TREE_OPERAND (arg0, 1), true))
> + {
> + tem = fold_build2_loc (loc, ncode, type, TREE_OPERAND (arg0, 1),
> + arg1);
> + return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
> + tem);
> + }
> + /* Needed for sequence points to handle trappings, and side-effects. */
> + else if (!TREE_SIDE_EFFECTS (arg0)
> + && simple_operand_p (arg0, true))
> + return fold_build2_loc (loc, ncode, type, arg0, arg1);
> + }
> +
Ciao,
Michael.
