v3d: use inc/dec tmu operation with image atomic sub/add of 1

This allows to remove a mov of 1/-1, as it is implicit with the
operation.

As with atomic inc/dec/add, usual shader-db set doesn't include any
GLES shader using it. So using as workaround vk-gl-cts shaders, we get
this:

total instructions in shared programs: 1217013 -> 1217006 (<.01%)
instructions in affected programs: 53 -> 46 (-13.21%)
helped: 2
HURT: 0

One of the helped shader went from 40 to 34 instructions.

Reviewed-by: Eric Anholt <eric@anholt.net>
This commit is contained in:
Alejandro Piñeiro
2019-06-25 15:02:56 +02:00
parent 2e22879115
commit 85b78f96a6

View File

@@ -251,7 +251,7 @@ v3d40_image_load_store_tmu_op(nir_intrinsic_instr *instr)
case nir_intrinsic_image_deref_store:
return V3D_TMU_OP_REGULAR;
case nir_intrinsic_image_deref_atomic_add:
return V3D_TMU_OP_WRITE_ADD_READ_PREFETCH;
return v3d_get_op_for_atomic_add(instr, 3);
case nir_intrinsic_image_deref_atomic_min:
return V3D_TMU_OP_WRITE_UMIN_FULL_L1_CLEAR;
case nir_intrinsic_image_deref_atomic_max:
@@ -292,11 +292,16 @@ v3d40_vir_emit_image_load_store(struct v3d_compile *c,
struct V3D41_TMU_CONFIG_PARAMETER_2 p2_unpacked = { 0 };
/* XXX perf: We should turn add/sub of 1 to inc/dec. Perhaps NIR
* wants to have support for inc/dec?
*/
p2_unpacked.op = v3d40_image_load_store_tmu_op(instr);
/* If we were able to replace atomic_add for an inc/dec, then we
* need/can to do things slightly different, like not loading the
* amount to add/sub, as that is implicit.
*/
bool atomic_add_replaced = (instr->intrinsic == nir_intrinsic_image_deref_atomic_add &&
(p2_unpacked.op == V3D_TMU_OP_WRITE_AND_READ_INC ||
p2_unpacked.op == V3D_TMU_OP_WRITE_OR_READ_DEC));
bool is_1d = false;
switch (glsl_get_sampler_dim(sampler_type)) {
case GLSL_SAMPLER_DIM_1D:
@@ -364,7 +369,8 @@ v3d40_vir_emit_image_load_store(struct v3d_compile *c,
vir_WRTMUC(c, QUNIFORM_CONSTANT, p2_packed);
/* Emit the data writes for atomics or image store. */
if (instr->intrinsic != nir_intrinsic_image_deref_load) {
if (instr->intrinsic != nir_intrinsic_image_deref_load &&
!atomic_add_replaced) {
/* Vector for stores, or first atomic argument */
struct qreg src[4];
for (int i = 0; i < nir_intrinsic_src_components(instr, 3); i++) {