[Mesa-dev] [PATCH v5 08/34] nvir/nir: run some passes to make the conversion easier

[Karol Herbst]

v2: add constant_folding

Signed-off-by: Karol Herbst <kherbst at redhat.com>
---
 .../drivers/nouveau/codegen/nv50_ir_from_nir.cpp   | 40 ++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_nir.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_nir.cpp
index 73527d4800..148db464bd 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_nir.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_nir.cpp
@@ -29,6 +29,12 @@
 #include "codegen/nv50_ir_lowering_helper.h"
 #include "codegen/nv50_ir_util.h"
 
+static int
+type_size(const struct glsl_type *type)
+{
+   return glsl_count_attribute_slots(type, false);
+}
+
 namespace {
 
 using namespace nv50_ir;
@@ -50,6 +56,40 @@ Converter::Converter(Program *prog, nir_shader *nir, nv50_ir_prog_info *info)
 bool
 Converter::run()
 {
+   bool progress;
+
+   if (prog->dbgFlags & NV50_IR_DEBUG_BASIC)
+      nir_print_shader(nir, stderr);
+
+   // converts intrinsic load_var to intrinsic load_uniform
+   NIR_PASS_V(nir, nir_lower_io, nir_var_all, type_size, (nir_lower_io_options)0);
+
+   NIR_PASS_V(nir, nir_lower_regs_to_ssa);
+   NIR_PASS_V(nir, nir_lower_load_const_to_scalar);
+
+   do {
+      progress = false;
+      // we need this to_ssa otherwise the later opts are less effective
+      NIR_PASS_V(nir, nir_lower_vars_to_ssa);
+      NIR_PASS(progress, nir, nir_lower_alu_to_scalar);
+      NIR_PASS(progress, nir, nir_lower_phis_to_scalar);
+      // some ops depend on having constant as sources, but those can also
+      // point to expressions made from constants like 0 + 1
+      NIR_PASS(progress, nir, nir_opt_constant_folding);
+      NIR_PASS(progress, nir, nir_copy_prop);
+      NIR_PASS(progress, nir, nir_opt_dce);
+      NIR_PASS(progress, nir, nir_opt_dead_cf);
+   } while (progress);
+
+   NIR_PASS_V(nir, nir_remove_dead_variables, nir_var_local);
+   NIR_PASS_V(nir, nir_convert_from_ssa, true);
+
+   /* Garbage collect dead instructions */
+   nir_sweep(nir);
+
+   if (prog->dbgFlags & NV50_IR_DEBUG_BASIC)
+      nir_print_shader(nir, stderr);
+
    return false;
 }
 
-- 
2.14.3