i965/vec4: Use NIR remapping for VS attributes

The NIR pass already handles remapping system values to attributes for
us so we delete the system value code as part of the conversion.

We also change nir_lower_vs_inputs to take an explicit inputs_read
bitmask and pass in the inputs_read from prog_data instead from pulling
it out of NIR.  This is because the version in prog_data may get
EDGEFLAG added to it on some old platforms.

Reviewed-by: Alejandro Piñeiro <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

1 files changed, 24 insertions, 36 deletions

diff --git a/src/intel/compiler/brw_vec4.cpp b/src/intel/compiler/brw_vec4.cpp
index a673dd6820b..f936429bbfc 100644
--- a/src/intel/compiler/brw_vec4.cpp
+++ b/src/intel/compiler/brw_vec4.cpp
@@ -1740,40 +1740,23 @@ vec4_visitor::lower_attributes_to_hw_regs(const int *attribute_map,
 int
 vec4_vs_visitor::setup_attributes(int payload_reg)
 {
-   int nr_attributes;
-   int attribute_map[VERT_ATTRIB_MAX + 2];
-   memset(attribute_map, 0, sizeof(attribute_map));
-
-   nr_attributes = 0;
-   GLbitfield64 vs_inputs = vs_prog_data->inputs_read;
-   while (vs_inputs) {
-      GLuint first = ffsll(vs_inputs) - 1;
-      int needed_slots =
-         (vs_prog_data->double_inputs_read & BITFIELD64_BIT(first)) ? 2 : 1;
-      for (int c = 0; c < needed_slots; c++) {
-         attribute_map[first + c] = payload_reg + nr_attributes;
-         nr_attributes++;
-         vs_inputs &= ~BITFIELD64_BIT(first + c);
+   foreach_block_and_inst(block, vec4_instruction, inst, cfg) {
+      for (int i = 0; i < 3; i++) {
+         if (inst->src[i].file == ATTR) {
+            assert(inst->src[i].offset % REG_SIZE == 0);
+            int grf = payload_reg + inst->src[i].nr +
+                      inst->src[i].offset / REG_SIZE;
+
+            struct brw_reg reg = brw_vec8_grf(grf, 0);
+            reg.swizzle = inst->src[i].swizzle;
+            reg.type = inst->src[i].type;
+            reg.abs = inst->src[i].abs;
+            reg.negate = inst->src[i].negate;
+            inst->src[i] = reg;
+         }
       }
    }
 
-   /* VertexID is stored by the VF as the last vertex element, but we
-    * don't represent it with a flag in inputs_read, so we call it
-    * VERT_ATTRIB_MAX.
-    */
-   if (vs_prog_data->uses_vertexid || vs_prog_data->uses_instanceid ||
-       vs_prog_data->uses_basevertex || vs_prog_data->uses_baseinstance) {
-      attribute_map[VERT_ATTRIB_MAX] = payload_reg + nr_attributes;
-      nr_attributes++;
-   }
-
-   if (vs_prog_data->uses_drawid) {
-      attribute_map[VERT_ATTRIB_MAX + 1] = payload_reg + nr_attributes;
-      nr_attributes++;
-   }
-
-   lower_attributes_to_hw_regs(attribute_map, false /* interleaved */);
-
    return payload_reg + vs_prog_data->nr_attribute_slots;
 }
 
@@ -2771,10 +2754,6 @@ brw_compile_vs(const struct brw_compiler *compiler, void *log_data,
    const bool is_scalar = compiler->scalar_stage[MESA_SHADER_VERTEX];
    nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
    shader = brw_nir_apply_sampler_key(shader, compiler, &key->tex, is_scalar);
-   brw_nir_lower_vs_inputs(shader, is_scalar,
-                           use_legacy_snorm_formula, key->gl_attrib_wa_flags);
-   brw_nir_lower_vue_outputs(shader, is_scalar);
-   shader = brw_postprocess_nir(shader, compiler, is_scalar);
 
    const unsigned *assembly = NULL;
 
@@ -2783,15 +2762,24 @@ brw_compile_vs(const struct brw_compiler *compiler, void *log_data,
        * the edge flag from VERT_ATTRIB_EDGEFLAG.  This will be done
        * automatically by brw_vec4_visitor::emit_urb_slot but we need to
        * ensure that prog_data->inputs_read is accurate.
+       *
+       * In order to make late NIR passes aware of the change, we actually
+       * whack shader->info.inputs_read instead.  This is safe because we just
+       * made a copy of the shader.
        */
       assert(!is_scalar);
       assert(key->copy_edgeflag);
-      prog_data->inputs_read |= VERT_BIT_EDGEFLAG;
+      shader->info.inputs_read |= VERT_BIT_EDGEFLAG;
    }
 
    prog_data->inputs_read = shader->info.inputs_read;
    prog_data->double_inputs_read = shader->info.double_inputs_read;
 
+   brw_nir_lower_vs_inputs(shader, use_legacy_snorm_formula,
+                           key->gl_attrib_wa_flags);
+   brw_nir_lower_vue_outputs(shader, is_scalar);
+   shader = brw_postprocess_nir(shader, compiler, is_scalar);
+
    prog_data->base.clip_distance_mask =
       ((1 << shader->info.clip_distance_array_size) - 1);
    prog_data->base.cull_distance_mask =