agx/opt_preamble: improve preamble cost function
save lots of uniforms by no longer pushing silly things.
total instructions in shared programs: 2039473 -> 2039480 (<.01%)
instructions in affected programs: 28335 -> 28342 (0.02%)
helped: 51
HURT: 47
Inconclusive result (value mean confidence interval includes 0).
total bytes in shared programs: 13983778 -> 13983802 (<.01%)
bytes in affected programs: 451678 -> 451702 (<.01%)
helped: 151
HURT: 79
Inconclusive result (value mean confidence interval includes 0).
total regs in shared programs: 590373 -> 590670 (0.05%)
regs in affected programs: 2354 -> 2651 (12.62%)
helped: 13
HURT: 65
Regs are HURT.
total uniforms in shared programs: 1532271 -> 1516549 (-1.03%)
uniforms in affected programs: 295709 -> 279987 (-5.32%)
helped: 2302
HURT: 0
Uniforms are helped.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28483>
diff --git a/src/asahi/compiler/agx_nir_opt_preamble.c b/src/asahi/compiler/agx_nir_opt_preamble.c
index d7cf487..79451c8 100644
--- a/src/asahi/compiler/agx_nir_opt_preamble.c
+++ b/src/asahi/compiler/agx_nir_opt_preamble.c
@@ -6,6 +6,8 @@
#include "compiler/nir/nir_builder.h"
#include "agx_compiler.h"
+#include "nir.h"
+#include "nir_opcodes.h"
static void
def_size(nir_def *def, unsigned *size, unsigned *align)
@@ -16,6 +18,41 @@
*align = bit_size / 16;
}
+static bool
+all_uses_float(nir_def *def)
+{
+ nir_foreach_use_including_if(use, def) {
+ if (nir_src_is_if(use))
+ return false;
+
+ nir_instr *use_instr = nir_src_parent_instr(use);
+ if (use_instr->type != nir_instr_type_alu)
+ return false;
+
+ nir_alu_instr *use_alu = nir_instr_as_alu(use_instr);
+ unsigned src_index = ~0;
+ for (unsigned i = 0; i < nir_op_infos[use_alu->op].num_inputs; i++) {
+ if (&use_alu->src[i].src == use) {
+ src_index = i;
+ break;
+ }
+ }
+
+ assert(src_index != ~0);
+ nir_alu_type src_type = nir_alu_type_get_base_type(
+ nir_op_infos[use_alu->op].input_types[src_index]);
+
+ if (src_type != nir_type_float)
+ return false;
+
+ /* No float modifiers on G13 */
+ if (use_alu->op == nir_op_fmax || use_alu->op == nir_op_fmin)
+ return false;
+ }
+
+ return true;
+}
+
static float
instr_cost(nir_instr *instr, const void *data)
{
@@ -37,12 +74,21 @@
/* Texturing involes lots of memory bandwidth */
return 20.0;
- case nir_instr_type_alu:
- /* We optimistically assume that moves get coalesced */
- if (nir_op_is_vec_or_mov(nir_instr_as_alu(instr)->op))
- return 0.0;
- else
- return 2.0;
+ case nir_instr_type_alu: {
+ nir_alu_instr *alu = nir_instr_as_alu(instr);
+
+ switch (alu->op) {
+ case nir_op_fneg:
+ case nir_op_fabs:
+ case nir_op_f2f32:
+ /* Float source modifiers will be propagated */
+ return all_uses_float(&alu->def) ? 0.0 : 2.0;
+
+ default:
+ /* We optimistically assume that moves get coalesced */
+ return nir_op_is_vec_or_mov(alu->op) ? 0.0 : 2.0;
+ }
+ }
default:
return 1.0;
