On Thu, Sep 3, 2020 at 11:20 AM luoxhu <luo...@linux.ibm.com> wrote: > > > > On 2020/9/2 17:30, Richard Biener wrote: > >> so maybe bypass convert_vector_to_array_for_subscript for special > >> circumstance > >> like "i = v[n%4]" or "v[n&3]=i" to generate vec_extract or vec_insert > >> builtin > >> call a relative simpler method? > > I think you have it backward. You need to work with what > > convert_vector_to_array_for_subscript > > gives and deal with it during RTL expansion / optimization to generate > > more optimal > > code for power. The goal is to have as little target specific > > builtins during the GIMPLE > > optimization phase (because we cannot work out its semantics in optimizers). > > OK, got it, will add optabs vec_insert and expand > "VIEW_CONVERT_EXPR<int[4]>(v1)[_1] = i_6(D);" > expressions to rs6000_expand_vector_insert instead of builtin call. > vec_extract already has optabs and "i = v[n%4]" should be in another patch > after this.
There is already vec_set and vec_extract - the question is whether the expander tries those for variable index. Richard. > > Thanks, > Xionghu >
