i965/vec4/nir: allocate two registers for dvec3/dvec4

v2 (Curro):
  - Do not special-case for a bit-size of 64, divide the bit_size by 32
    instead.
  - Use DIV_ROUND_UP so we can handle sub-32-bit types.

v3 (Ian):
  - Make num_regs const.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
1 file changed