Hello,
as discussed around
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg00041.html
we are currently guessing the type of a?b:c incorrectly. This does not
affect current simplifications, because the only 'cond' in output patterns
are at the outermost level, so their type is forced to 'type' and never
guessed. Indeed, the patch does not change the generated *-match.c. It
would allow removing an explicit cond:itype in a patch posted by Jeff.
I tested it on a dummy .pd file containing:
(simplify
(plus @0 (plus @1 @2))
(negate (cond @0 @1 @2)))
and the generated files differ by:
- res = fold_build3_loc (loc, COND_EXPR, TREE_TYPE (ops1[0]), ops1[0],
ops1[1], ops1[2]);
+ res = fold_build3_loc (loc, COND_EXPR, TREE_TYPE (ops1[1]), ops1[0],
ops1[1], ops1[2]);
(and something similar for gimple)
I wondered about using something like
VOID_TYPE_P (TREE_TYPE (ops1[1])) ? TREE_TYPE (ops1[2]) : TREE_TYPE (ops1[1])
but I don't think that will be necessary.
Bootstrap is currently broken on many platforms with comparison failures,
but since it went that far and generated the same *-match.c files, that
seems sufficient testing.
2015-06-08 Marc Glisse <marc.gli...@inria.fr>
* genmatch.c (expr::gen_transform): For conditions, guess the type
from the second operand.
--
Marc GlisseIndex: gcc/genmatch.c
===================================================================
--- gcc/genmatch.c (revision 224186)
+++ gcc/genmatch.c (working copy)
@@ -1702,20 +1702,27 @@ expr::gen_transform (FILE *f, const char
type = optype;
}
else if (is_a <operator_id *> (operation)
&& !strcmp (as_a <operator_id *> (operation)->tcc, "tcc_comparison"))
{
/* comparisons use boolean_type_node (or what gets in), but
their operands need to figure out the types themselves. */
sprintf (optype, "boolean_type_node");
type = optype;
}
+ else if (*operation == COND_EXPR
+ || *operation == VEC_COND_EXPR)
+ {
+ /* Conditions are of the same type as their first alternative. */
+ sprintf (optype, "TREE_TYPE (ops%d[1])", depth);
+ type = optype;
+ }
else
{
/* Other operations are of the same type as their first operand. */
sprintf (optype, "TREE_TYPE (ops%d[0])", depth);
type = optype;
}
if (!type)
fatal ("two conversions in a row");
fprintf (f, "{\n");
