Hello,
because of an other bug, __builtin_constant_p is ignored in some cases,
and this bug in wide_int went unnoticed. I am fixing it by making it match
more closely the comment above.
Bootstrap+regtest together with a fix for __builtin_constant_p on
x86_64-pc-linux-gnu.
2019-07-11 Marc Glisse <[email protected]>
* wide-int.h (wi::lshift): Reject negative values for the fast path.
--
Marc GlisseIndex: gcc/wide-int.h
===================================================================
--- gcc/wide-int.h (revision 273306)
+++ gcc/wide-int.h (working copy)
@@ -3025,22 +3025,22 @@ wi::lshift (const T1 &x, const T2 &y)
handle the case where the shift value is constant and the
result is a single nonnegative HWI (meaning that we don't
need to worry about val[1]). This is particularly common
for converting a byte count to a bit count.
For variable-precision integers like wide_int, handle HWI
and sub-HWI integers inline. */
if (STATIC_CONSTANT_P (xi.precision > HOST_BITS_PER_WIDE_INT)
? (STATIC_CONSTANT_P (shift < HOST_BITS_PER_WIDE_INT - 1)
&& xi.len == 1
- && xi.val[0] <= (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT)
- HOST_WIDE_INT_MAX >> shift))
+ && xi.val[0] >= 0
+ && xi.val[0] <= HOST_WIDE_INT_MAX >> shift)
: precision <= HOST_BITS_PER_WIDE_INT)
{
val[0] = xi.ulow () << shift;
result.set_len (1);
}
else
result.set_len (lshift_large (val, xi.val, xi.len,
precision, shift));
}
return result;
