[Mesa-dev] [PATCH 03/10] i965/nir: Report NIR instruction counts (in SSA form) via KHR_debug.

[Kenneth Graunke]

This allows us to count NIR instructions via shader-db.

Use "run" as normal.  The results file will contain both NIR and
assembly.

Then, to generate a NIR report:
./report.py <(grep    NIR results/foo) <(grep    NIR results/bar)

Or, to generate an i965 report:
./report.py <(grep -v NIR results/foo) <(grep -v NIR results/bar)

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_fs_nir.cpp | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

I'm guessing the counting should really go in nir proper.
This is what I used to generate the statistics, in case people were
wondering.

diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
index 2d30321..0eb137f 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
@@ -49,6 +49,28 @@ nir_optimize(nir_shader *nir)
    } while (progress);
 }
 
+static bool
+count_nir_instrs_in_block(nir_block *block, void *state)
+{
+   int *count = (int *) state;
+   nir_foreach_instr(block, instr) {
+      *count = *count + 1;
+   }
+   return true;
+}
+
+static int
+count_nir_instrs(nir_shader *nir)
+{
+   int count = 0;
+   nir_foreach_overload(nir, overload) {
+      if (!overload->impl)
+         continue;
+      nir_foreach_block(overload->impl, count_nir_instrs_in_block, &count);
+   }
+   return count;
+}
+
 void
 fs_visitor::emit_nir_code()
 {
@@ -99,6 +121,16 @@ fs_visitor::emit_nir_code()
       nir_print_shader(nir, stderr);
    }
 
+   if (dispatch_width == 8) {
+      static GLuint msg_id = 0;
+      _mesa_gl_debug(&brw->ctx, &msg_id,
+                     MESA_DEBUG_SOURCE_SHADER_COMPILER,
+                     MESA_DEBUG_TYPE_OTHER,
+                     MESA_DEBUG_SEVERITY_NOTIFICATION,
+                     "FS NIR shader: %d inst\n",
+                     count_nir_instrs(nir));
+   }
+
    nir_convert_from_ssa(nir);
    nir_validate_shader(nir);
    nir_lower_vec_to_movs(nir);
-- 
2.2.2