CMP.Z doesn't work on Gen4-5 because the boolean isn't guaranteed to be
0 or 0xFFFFFFFF - only the low bit is defined.
We can call emit_bool_to_cond_code to generate the condition in f0.0;
the last instruction will generate the flag value. We can patch it to
use f0.1, and negate the condition.
Fixes discard tests on Gen4-5.
Haswell shader-db stats:
total instructions in shared programs: 5770279 -> 5769112 (-0.02%)
instructions in affected programs: 64342 -> 63175 (-1.81%)
helped: 1069
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
*/
fs_inst *cmp;
if (ir->condition) {
- ir->condition->accept(this);
- cmp = emit(CMP(reg_null_f, this->result, fs_reg(0), BRW_CONDITIONAL_Z));
+ emit_bool_to_cond_code(ir->condition);
+ cmp = (fs_inst *) this->instructions.get_tail();
+ cmp->conditional_mod = brw_negate_cmod(cmp->conditional_mod);
} else {
fs_reg some_reg = fs_reg(retype(brw_vec8_grf(0, 0),
BRW_REGISTER_TYPE_UW));