OpenHarmony/third_party_mesa3d
2
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

nir: Transform discard_if(true) into discard

Browse Source 
Noticed while reviewing Tim Arceri's NIR inlining series.

Without his series:

instructions in affected programs: 16 -> 14 (-12.50%)
helped: 2

With his series:

instructions in affected programs: 196 -> 174 (-11.22%)
helped: 22

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This commit is contained in:
Matt Turner
2018-04-26 21:25:42 -07:00
parent ea1fff4416
commit ed5af94373
1 changed files with 16 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
src/compiler/nir/nir_opt_constant_folding.c
View File

@@ -167,7 +167,22 @@ constant_fold_intrinsic_instr(nir_intrinsic_instr *instr)
if (instr->intrinsic == nir_intrinsic_discard_if) {
nir_const_value *src_val = nir_src_as_const_value(instr->src[0]);
if (src_val && src_val->u32[0] == 0) {
if (src_val && src_val->u32[0] == NIR_FALSE) {
nir_instr_remove(&instr->instr);
progress = true;
} else if (src_val && src_val->u32[0] == NIR_TRUE) {
/* This method of getting a nir_shader * from a nir_instr is
* admittedly gross, but given the rarity of hitting this case I think
* it's preferable to plumbing an otherwise unused nir_shader *
* parameter through four functions to get here.
*/
nir_cf_node *cf_node = &instr->instr.block->cf_node;
nir_function_impl *impl = nir_cf_node_get_function(cf_node);
nir_shader *shader = impl->function->shader;
nir_intrinsic_instr *discard =
nir_intrinsic_instr_create(shader, nir_intrinsic_discard);
nir_instr_insert_before(&instr->instr, &discard->instr);
nir_instr_remove(&instr->instr);
progress = true;
}