[Mesa-dev] [RFC PATCH 1/2] nir: Silently bail on regs for gather_ssa_types

[Alyssa Rosenzweig]

In the future, we'll really need to implement register support for
nir_gather_ssa_types, but at present, for some limited applications it
can be ok to just bail on these and set neither int_types nor
float_types, rather than assert'ing out and crashing. It's not correct,
per se, but existing users will not be regressed, and for the limited
use in Panfrost following the imov/fmov merge, it'll hold us over until
this pass can be extended.

Signed-off-by: Alyssa Rosenzweig <alyssa at rosenzweig.io>
Cc: Jason Ekstrand <jason at jlekstrand.net>
---
 src/compiler/nir/nir_gather_ssa_types.c | 60 ++++++++++++++++++-------
 1 file changed, 43 insertions(+), 17 deletions(-)

diff --git a/src/compiler/nir/nir_gather_ssa_types.c b/src/compiler/nir/nir_gather_ssa_types.c
index 73bd0f9bc6a..a63e9295d27 100644
--- a/src/compiler/nir/nir_gather_ssa_types.c
+++ b/src/compiler/nir/nir_gather_ssa_types.c
@@ -99,7 +99,11 @@ nir_gather_ssa_types(nir_function_impl *impl,
             switch (instr->type) {
             case nir_instr_type_alu: {
                nir_alu_instr *alu = nir_instr_as_alu(instr);
-               assert(alu->dest.dest.is_ssa);
+
+               /* TODO: registers */
+               if (!alu->dest.dest.is_ssa)
+                  continue;
+
                const nir_op_info *info = &nir_op_infos[alu->op];
                switch (alu->op) {
                case nir_op_imov:
@@ -108,7 +112,9 @@ nir_gather_ssa_types(nir_function_impl *impl,
                case nir_op_vec3:
                case nir_op_vec4:
                   for (unsigned i = 0; i < info->num_inputs; i++) {
-                     assert(alu->src[i].src.is_ssa);
+                     if (!alu->src[i].src.is_ssa)
+                        continue;
+
                      copy_types(alu->src[i].src.ssa->index,
                                 alu->dest.dest.ssa.index,
                                 float_types, int_types, &progress);
@@ -117,19 +123,26 @@ nir_gather_ssa_types(nir_function_impl *impl,
 
                case nir_op_bcsel:
                case nir_op_b32csel:
-                  set_type(alu->src[0].src.ssa->index, nir_type_bool,
-                           float_types, int_types, &progress);
-                  copy_types(alu->src[1].src.ssa->index,
-                             alu->dest.dest.ssa.index,
-                             float_types, int_types, &progress);
-                  copy_types(alu->src[2].src.ssa->index,
-                             alu->dest.dest.ssa.index,
-                             float_types, int_types, &progress);
+                  if (alu->src[0].src.is_ssa)
+                     set_type(alu->src[0].src.ssa->index, nir_type_bool,
+                              float_types, int_types, &progress);
+
+                  if (alu->src[1].src.is_ssa)
+                     copy_types(alu->src[1].src.ssa->index,
+                                alu->dest.dest.ssa.index,
+                                float_types, int_types, &progress);
+
+                  if (alu->src[2].src.is_ssa)
+                     copy_types(alu->src[2].src.ssa->index,
+                                alu->dest.dest.ssa.index,
+                                float_types, int_types, &progress);
                   break;
 
                default:
                   for (unsigned i = 0; i < info->num_inputs; i++) {
-                     assert(alu->src[i].src.is_ssa);
+                     if (!alu->src[i].src.is_ssa)
+                        continue;
+
                      set_type(alu->src[i].src.ssa->index, info->input_types[i],
                               float_types, int_types, &progress);
                   }
@@ -142,12 +155,17 @@ nir_gather_ssa_types(nir_function_impl *impl,
             case nir_instr_type_tex: {
                nir_tex_instr *tex = nir_instr_as_tex(instr);
                for (unsigned i = 0; i < tex->num_srcs; i++) {
-                  assert(tex->src[i].src.is_ssa);
+                  if (!tex->src[i].src.is_ssa)
+                     continue;
+
                   set_type(tex->src[i].src.ssa->index,
                            nir_tex_instr_src_type(tex, i),
                            float_types, int_types, &progress);
                }
-               assert(tex->dest.is_ssa);
+
+               if (!tex->dest.is_ssa)
+                  continue;
+
                set_type(tex->dest.ssa.index, tex->dest_type,
                         float_types, int_types, &progress);
                break;
@@ -162,7 +180,9 @@ nir_gather_ssa_types(nir_function_impl *impl,
                case nir_intrinsic_load_deref: {
                   nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
 
-                  assert(intrin->dest.is_ssa);
+                  if (!intrin->dest.is_ssa)
+                     break;
+
                   set_type(intrin->dest.ssa.index,
                            nir_get_nir_type_for_glsl_type(deref->type),
                            float_types, int_types, &progress);
@@ -172,7 +192,9 @@ nir_gather_ssa_types(nir_function_impl *impl,
                case nir_intrinsic_store_deref: {
                   nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
 
-                  assert(intrin->src[1].is_ssa);
+                  if (!intrin->src[1].is_ssa)
+                     break;
+
                   set_type(intrin->src[1].ssa->index,
                            nir_get_nir_type_for_glsl_type(deref->type),
                            float_types, int_types, &progress);
@@ -187,7 +209,9 @@ nir_gather_ssa_types(nir_function_impl *impl,
                    */
                   nir_src *offset_src = nir_get_io_offset_src(intrin);
                   if (offset_src) {
-                     assert(offset_src->is_ssa);
+                     if (!offset_src->is_ssa)
+                        break;
+
                      set_type(offset_src->ssa->index, nir_type_int,
                               float_types, int_types, &progress);
                   }
@@ -201,7 +225,9 @@ nir_gather_ssa_types(nir_function_impl *impl,
                nir_phi_instr *phi = nir_instr_as_phi(instr);
                assert(phi->dest.is_ssa);
                nir_foreach_phi_src(src, phi) {
-                  assert(src->src.is_ssa);
+                  if (!src->src.is_ssa)
+                     continue;
+
                   copy_types(src->src.ssa->index, phi->dest.ssa.index,
                              float_types, int_types, &progress);
                }
-- 
2.20.1