[Bug tree-optimization/102583] [x86] Failure to optimize 32-byte integer vector conversion to 16-byte float vector properly when converting upper part with -mavx2

[crazylht at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102583

--- Comment #3 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Hongtao.liu from comment #2)
> Simplify
>   _4 = VEC_PERM_EXPR <_1, _1, { 4, 5, 6, 7, 4, 5, 6, 7 }>;
>   _5 = BIT_FIELD_REF <_4, 128, 0>;
> 
> to
> 
> _5 = BIT_FIELD_REF <_1, 128, 128>;
> 
> in match.pd?

maybe forwprop this
15  _1 = *srcp_7(D);
16  _2 = BIT_FIELD_REF <_1, 32, 128>;
17  _3 = BIT_FIELD_REF <_1, 32, 160>;
18  _4 = BIT_FIELD_REF <_1, 32, 192>;
19  _5 = BIT_FIELD_REF <_1, 32, 224>;
20  b_9 = {_2, _3, _4, _5};

directly into

b_9 = BIT_FIELD_REF <*srcp_7, 128, 128>;