From: Matt Turner <mattst88@gmail.com>
Date: Thu, 27 Feb 2020 18:48:37 +0000 (-0800)
Subject: intel/compiler: Discount NOPs from instruction counts
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e924181ea89e5e261f8aa24564c32ed22941e752;p=mesa.git

intel/compiler: Discount NOPs from instruction counts

Scheduler changes can cause changes in the number of instructions due to
this workaround, so just don't include NOPs in the instruction counts to
prevent shader-db noise.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4093>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4093>
---

diff --git a/src/intel/compiler/brw_fs_generator.cpp b/src/intel/compiler/brw_fs_generator.cpp
index 58d5fcc67c6..dd2e753abd1 100644
--- a/src/intel/compiler/brw_fs_generator.cpp
+++ b/src/intel/compiler/brw_fs_generator.cpp
@@ -1714,7 +1714,7 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width,
     * effect is already counted in spill/fill counts.
     */
    int spill_count = 0, fill_count = 0;
-   int loop_count = 0, send_count = 0;
+   int loop_count = 0, send_count = 0, nop_count = 0;
    bool is_accum_used = false;
 
    struct disasm_info *disasm_info = disasm_initialize(devinfo, cfg);
@@ -1744,6 +1744,12 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width,
           inst->dst.component_size(inst->exec_size) > REG_SIZE) {
          brw_NOP(p);
          last_insn_offset = p->next_insn_offset;
+
+         /* In order to avoid spurious instruction count differences when the
+          * instruction schedule changes, keep track of the number of inserted
+          * NOPs.
+          */
+         nop_count++;
       }
 
       /* GEN:BUG:14010017096:
@@ -2459,7 +2465,7 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width,
                               "Promoted %u constants, "
                               "compacted %d to %d bytes.",
                               _mesa_shader_stage_to_abbrev(stage),
-                              dispatch_width, before_size / 16,
+                              dispatch_width, before_size / 16 - nop_count,
                               loop_count, cfg->cycle_count,
                               spill_count, fill_count, send_count,
                               shader_stats.scheduler_mode,
@@ -2467,7 +2473,7 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width,
                               before_size, after_size);
    if (stats) {
       stats->dispatch_width = dispatch_width;
-      stats->instructions = before_size / 16;
+      stats->instructions = before_size / 16 - nop_count;
       stats->loops = loop_count;
       stats->cycles = cfg->cycle_count;
       stats->spills = spill_count;