Enable getting the results of a transform feedback overflow query with a
buffer object.
v4:
- hsw_overflow_result_to_gpr0 a public function, so it can be used
by conditional render. (Kenneth)
- fix typo grp0/gpr0 (Kenneth)
- rename load_gen_written_data_to_regs to
load_overflow_data_to_cs_gprs (Kenneth)
Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>