All normal RTL expressions can be used with vector modes; they are interpreted as operating on each part of the vector independently. Additionally, there are a few new expressions to describe specific vector operations.
(vec_merge:m vec1 vec2 items
const_int; a zero bit indicates the corresponding element in the result vector is taken from vec2 while a set bit indicates it is taken from vec1.
(vec_select:m vec1 selection
parallelthat contains a
const_intfor each of the subparts of the result vector, giving the number of the source subpart that should be stored into it. The result mode m is either the submode for a single element of vec1 (if only one subpart is selected), or another vector mode with that element submode (if multiple subparts are selected).
(vec_concat:m x1 x2