On Tue, 13 Aug 2019, Robin Dapp wrote:
+/* ((T)(A)) + CST -> (T)(A + CST) */
+#if GIMPLE
+ (simplify
+ (plus (convert SSA_NAME@0) INTEGER_CST@1)
+ (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
+ && INTEGRAL_TYPE_P (type)
I have become rather wary of INTEGRAL_TYPE_P recently because it includes
enum types, which with -fstrict-enum can have a surprising behavior. If I
have
enum E { A, B, C };
and e has type enum E, with -fstrict-enum, do your tests manage to prevent
(long)e+1 from becoming (long)(e+1) with an unsafe operation done in the
enum type?
+ && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (@0))
+ && int_fits_type_p (@1, TREE_TYPE (@0)))
+ /* Perform binary operation inside the cast if the constant fits
+ and (A + CST)'s range does not overflow. */
+ (with
+ {
+ wi::overflow_type min_ovf = wi::OVF_OVERFLOW,
+ max_ovf = wi::OVF_OVERFLOW;
+ tree inner_type = TREE_TYPE (@0);
+
+ wide_int w1 = w1.from (wi::to_wide (@1), TYPE_PRECISION (inner_type),
+ TYPE_SIGN (inner_type));
+
+ wide_int wmin0, wmax0;
+ if (get_range_info (@0, &wmin0, &wmax0) == VR_RANGE)
+ {
+ wi::add (wmin0, w1, TYPE_SIGN (inner_type), &min_ovf);
+ wi::add (wmax0, w1, TYPE_SIGN (inner_type), &max_ovf);
+ }
+ }
+ (if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
+ (convert (plus @0 { {wide_int_to_tree (TREE_TYPE (@0), w1)}; })))
+ )))
+#endif
+
--
Marc Glisse