static tree
chrec_convert_1 (tree type, tree chrec, tree at_stmt,
bool use_overflow_semantics)
{
tree ct, res;
tree base, step;
struct loop *loop;
if (automatically_generated_chrec_p (chrec))
return chrec;
ct = chrec_type (chrec);
if (ct == type)
return chrec;
if (!evolution_function_is_affine_p (chrec))
goto keep_cast;
loop = current_loops->parray[CHREC_VARIABLE (chrec)];
base = CHREC_LEFT (chrec);
step = CHREC_RIGHT (chrec);
if (convert_affine_scev (loop, type, &base, &step, at_stmt,
use_overflow_semantics))
return build_polynomial_chrec (loop->num, base, step);
/* If we cannot propagate the cast inside the chrec, just keep the cast. */
keep_cast:
res = fold_convert (type, chrec);
/* Don't propagate overflows. */
if (CONSTANT_CLASS_P (res))
{
TREE_CONSTANT_OVERFLOW (res) = 0;
TREE_OVERFLOW (res) = 0;
}
/* But reject constants that don't fit in their type after conversion.
This can happen if TYPE_MIN_VALUE or TYPE_MAX_VALUE are not the
natural values associated with TYPE_PRECISION and TYPE_UNSIGNED,
and can cause problems later when computing niters of loops. Note
that we don't do the check before converting because we don't want
to reject conversions of negative chrecs to unsigned types. */
if (TREE_CODE (res) == INTEGER_CST
&& TREE_CODE (type) == INTEGER_TYPE
&& !int_fits_type_p (res, type))
res = chrec_dont_know;
return res;
}
tree
chrec_convert (tree type,
tree chrec)
{
tree ct;
if (automatically_generated_chrec_p (chrec))
return chrec;
ct = chrec_type (chrec);
if (ct == type)
return chrec;
if (TYPE_PRECISION (ct) < TYPE_PRECISION (type))
return count_ev_in_wider_type (type, chrec);
switch (TREE_CODE (chrec))
{
case POLYNOMIAL_CHREC:
return build_polynomial_chrec (CHREC_VARIABLE (chrec),
chrec_convert (type,
CHREC_LEFT (chrec)),
chrec_convert (type,
CHREC_RIGHT (chrec)));
default:
{
tree res = fold_convert (type, chrec);
/* Don't propagate overflows. */
TREE_OVERFLOW (res) = 0;
if (CONSTANT_CLASS_P (res))
TREE_CONSTANT_OVERFLOW (res) = 0;
/* But reject constants that don't fit in their type after conversion.
This can happen if TYPE_MIN_VALUE or TYPE_MAX_VALUE are not the
natural values associated with TYPE_PRECISION and TYPE_UNSIGNED,
and can cause problems later when computing niters of loops. Note
that we don't do the check before converting because we don't want
to reject conversions of negative chrecs to unsigned types. */
if (TREE_CODE (res) == INTEGER_CST
&& TREE_CODE (type) == INTEGER_TYPE
&& !int_fits_type_p (res, type))
res = chrec_dont_know;
return res;
}
}
}
