https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99863
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Also time to fix this stupid veclower behavior:
_7 = (unsigned int) _14;
_5 = {_7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7};
- v512u32_0_16 = _5 * v512u32_0_15(D);
+ _53 = {_7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7};
+ _54 = BIT_FIELD_REF <_53, 32, 0>;
+ _55 = BIT_FIELD_REF <v512u32_0_15(D), 32, 0>;
+ _56 = _54 * _55;
+ _57 = {_7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7};
+ _58 = BIT_FIELD_REF <_57, 32, 32>;
+ _59 = BIT_FIELD_REF <v512u32_0_15(D), 32, 32>;
+ _60 = _58 * _59;
...
instead of
_5 = {_7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7};
- v512u32_0_16 = _5 * v512u32_0_15(D);
_54 = BIT_FIELD_REF <_5, 32, 0>;
...
or even better
_5 = {_7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7, _7};
- v512u32_0_16 = _5 * v512u32_0_15(D);
+ _55 = BIT_FIELD_REF <v512u32_0_15(D), 32, 0>;
+ _56 = _7 * _55;
it's all "fixed" later by CSE of course.
The error might be involving the clever handling of
- v256u8_r_17 = _8 + _19;
+ _117 = BIT_FIELD_REF <_8, 64, 0>;
+ _118 = BIT_FIELD_REF <_19, 64, 0>;
+ _119 = _117 ^ _118;
+ _120 = _118 & 9187201950435737471;
+ _121 = _117 & 9187201950435737471;
+ _122 = _119 & 9259542123273814144;
+ _123 = _120 + _121;
+ _124 = _122 ^ _123;
+ _125 = BIT_FIELD_REF <_8, 64, 64>;
+ _126 = BIT_FIELD_REF <_19, 64, 64>;
...
+ _149 = {_124, _132, _140, _148};
+ _150 = VIEW_CONVERT_EXPR<v256u8>(_149);
+ v256u8_r_17 = _150;
it's enough to -fdisable-tree-forwprop4 (forwprop after veclower) to make
the problem show up so it might be as well an RTL optimization issue.
