1 files changed, 207 insertions, 53 deletions

diff --git a/src/compiler/nir/nir_gather_info.c b/src/compiler/nir/nir_gather_info.c
index 380140ad5ce..63c8a420fdf 100644
--- a/src/compiler/nir/nir_gather_info.c
+++ b/src/compiler/nir/nir_gather_info.c
@@ -21,9 +21,189 @@
  * IN THE SOFTWARE.
  */
 
+#include "main/mtypes.h"
 #include "nir.h"
 
 static void
+set_io_mask(nir_shader *shader, nir_variable *var, int offset, int len)
+{
+   for (int i = 0; i < len; i++) {
+      assert(var->data.location != -1);
+
+      int idx = var->data.location + offset + i;
+      bool is_patch_generic = var->data.patch &&
+                              idx != VARYING_SLOT_TESS_LEVEL_INNER &&
+                              idx != VARYING_SLOT_TESS_LEVEL_OUTER &&
+                              idx != VARYING_SLOT_BOUNDING_BOX0 &&
+                              idx != VARYING_SLOT_BOUNDING_BOX1;
+      uint64_t bitfield;
+
+      if (is_patch_generic) {
+         assert(idx >= VARYING_SLOT_PATCH0 && idx < VARYING_SLOT_TESS_MAX);
+         bitfield = BITFIELD64_BIT(idx - VARYING_SLOT_PATCH0);
+      }
+      else {
+         assert(idx < VARYING_SLOT_MAX);
+         bitfield = BITFIELD64_BIT(idx);
+      }
+
+      if (var->data.mode == nir_var_shader_in) {
+         if (is_patch_generic)
+            shader->info->patch_inputs_read |= bitfield;
+         else
+            shader->info->inputs_read |= bitfield;
+
+         /* double inputs read is only for vertex inputs */
+         if (shader->stage == MESA_SHADER_VERTEX &&
+             glsl_type_is_dual_slot(glsl_without_array(var->type)))
+            shader->info->double_inputs_read |= bitfield;
+
+         if (shader->stage == MESA_SHADER_FRAGMENT) {
+            shader->info->fs.uses_sample_qualifier |= var->data.sample;
+         }
+      } else {
+         assert(var->data.mode == nir_var_shader_out);
+         if (is_patch_generic) {
+            shader->info->patch_outputs_written |= bitfield;
+         } else if (!var->data.read_only) {
+            shader->info->outputs_written |= bitfield;
+         }
+
+         if (var->data.fb_fetch_output)
+            shader->info->outputs_read |= bitfield;
+      }
+   }
+}
+
+/**
+ * Mark an entire variable as used.  Caller must ensure that the variable
+ * represents a shader input or output.
+ */
+static void
+mark_whole_variable(nir_shader *shader, nir_variable *var)
+{
+   const struct glsl_type *type = var->type;
+   bool is_vertex_input = false;
+
+   if (nir_is_per_vertex_io(var, shader->stage)) {
+      assert(glsl_type_is_array(type));
+      type = glsl_get_array_element(type);
+   }
+
+   if (shader->stage == MESA_SHADER_VERTEX &&
+       var->data.mode == nir_var_shader_in)
+      is_vertex_input = true;
+
+   set_io_mask(shader, var, 0,
+               glsl_count_attribute_slots(type, is_vertex_input));
+}
+
+static unsigned
+get_io_offset(nir_deref_var *deref, bool is_vertex_input)
+{
+   unsigned offset = 0;
+
+   nir_deref *tail = &deref->deref;
+   while (tail->child != NULL) {
+      tail = tail->child;
+
+      if (tail->deref_type == nir_deref_type_array) {
+         nir_deref_array *deref_array = nir_deref_as_array(tail);
+
+         if (deref_array->deref_array_type == nir_deref_array_type_indirect) {
+            return -1;
+         }
+
+         offset += glsl_count_attribute_slots(tail->type, is_vertex_input) *
+            deref_array->base_offset;
+      }
+      /* TODO: we can get the offset for structs here see nir_lower_io() */
+   }
+
+   return offset;
+}
+
+/**
+ * Try to mark a portion of the given varying as used.  Caller must ensure
+ * that the variable represents a shader input or output.
+ *
+ * If the index can't be interpreted as a constant, or some other problem
+ * occurs, then nothing will be marked and false will be returned.
+ */
+static bool
+try_mask_partial_io(nir_shader *shader, nir_deref_var *deref)
+{
+   nir_variable *var = deref->var;
+   const struct glsl_type *type = var->type;
+
+   if (nir_is_per_vertex_io(var, shader->stage)) {
+      assert(glsl_type_is_array(type));
+      type = glsl_get_array_element(type);
+   }
+
+   /* The code below only handles:
+    *
+    * - Indexing into matrices
+    * - Indexing into arrays of (arrays, matrices, vectors, or scalars)
+    *
+    * For now, we just give up if we see varying structs and arrays of structs
+    * here marking the entire variable as used.
+    */
+   if (!(glsl_type_is_matrix(type) ||
+         (glsl_type_is_array(type) &&
+          (glsl_type_is_numeric(glsl_without_array(type)) ||
+           glsl_type_is_boolean(glsl_without_array(type)))))) {
+
+      /* If we don't know how to handle this case, give up and let the
+       * caller mark the whole variable as used.
+       */
+      return false;
+   }
+
+   bool is_vertex_input = false;
+   if (shader->stage == MESA_SHADER_VERTEX &&
+       var->data.mode == nir_var_shader_in)
+      is_vertex_input = true;
+
+   unsigned offset = get_io_offset(deref, is_vertex_input);
+   if (offset == -1)
+      return false;
+
+   unsigned num_elems;
+   unsigned elem_width = 1;
+   unsigned mat_cols = 1;
+   if (glsl_type_is_array(type)) {
+      num_elems = glsl_get_aoa_size(type);
+      if (glsl_type_is_matrix(glsl_without_array(type)))
+         mat_cols = glsl_get_matrix_columns(glsl_without_array(type));
+   } else {
+      num_elems = glsl_get_matrix_columns(type);
+   }
+
+   /* double element width for double types that takes two slots */
+   if (!is_vertex_input &&
+       glsl_type_is_dual_slot(glsl_without_array(type))) {
+      elem_width *= 2;
+   }
+
+   if (offset >= num_elems * elem_width * mat_cols) {
+      /* Constant index outside the bounds of the matrix/array.  This could
+       * arise as a result of constant folding of a legal GLSL program.
+       *
+       * Even though the spec says that indexing outside the bounds of a
+       * matrix/array results in undefined behaviour, we don't want to pass
+       * out-of-range values to set_io_mask() (since this could result in
+       * slots that don't exist being marked as used), so just let the caller
+       * mark the whole variable as used.
+       */
+      return false;
+   }
+
+   set_io_mask(shader, var, offset, elem_width);
+   return true;
+}
+
+static void
 gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader)
 {
    switch (instr->intrinsic) {
@@ -33,10 +213,24 @@ gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader)
       shader->info->fs.uses_discard = true;
       break;
 
+   case nir_intrinsic_interp_var_at_centroid:
+   case nir_intrinsic_interp_var_at_sample:
+   case nir_intrinsic_interp_var_at_offset:
+   case nir_intrinsic_load_var:
+   case nir_intrinsic_store_var:
+      if (instr->variables[0]->var->data.mode == nir_var_shader_in ||
+          instr->variables[0]->var->data.mode == nir_var_shader_out) {
+         if (!try_mask_partial_io(shader, instr->variables[0]))
+            mark_whole_variable(shader, instr->variables[0]->var);
+      }
+      break;
+
+   case nir_intrinsic_load_draw_id:
    case nir_intrinsic_load_front_face:
    case nir_intrinsic_load_vertex_id:
    case nir_intrinsic_load_vertex_id_zero_base:
    case nir_intrinsic_load_base_vertex:
+   case nir_intrinsic_load_base_instance:
    case nir_intrinsic_load_instance_id:
    case nir_intrinsic_load_sample_id:
    case nir_intrinsic_load_sample_pos:
@@ -47,6 +241,9 @@ gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader)
    case nir_intrinsic_load_local_invocation_index:
    case nir_intrinsic_load_work_group_id:
    case nir_intrinsic_load_num_work_groups:
+   case nir_intrinsic_load_tess_coord:
+   case nir_intrinsic_load_tess_level_outer:
+   case nir_intrinsic_load_tess_level_inner:
       shader->info->system_values_read |=
          (1 << nir_system_value_from_intrinsic(instr->intrinsic));
       break;
@@ -89,62 +286,9 @@ gather_info_block(nir_block *block, nir_shader *shader)
    }
 }
 
-/**
- * Returns the bits in the inputs_read, outputs_written, or
- * system_values_read bitfield corresponding to this variable.
- */
-static inline uint64_t
-get_io_mask(nir_variable *var, gl_shader_stage stage)
-{
-   assert(var->data.mode == nir_var_shader_in ||
-          var->data.mode == nir_var_shader_out ||
-          var->data.mode == nir_var_system_value);
-   assert(var->data.location >= 0);
-
-   const struct glsl_type *var_type = var->type;
-   if (stage == MESA_SHADER_GEOMETRY && var->data.mode == nir_var_shader_in) {
-      /* Most geometry shader inputs are per-vertex arrays */
-      if (var->data.location >= VARYING_SLOT_VAR0)
-         assert(glsl_type_is_array(var_type));
-
-      if (glsl_type_is_array(var_type))
-         var_type = glsl_get_array_element(var_type);
-   }
-
-   bool is_vertex_input = (var->data.mode == nir_var_shader_in &&
-                           stage == MESA_SHADER_VERTEX);
-   unsigned slots = glsl_count_attribute_slots(var_type, is_vertex_input);
-   return ((1ull << slots) - 1) << var->data.location;
-}
-
 void
 nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
 {
-   /* This pass does not yet support tessellation shaders */
-   assert(shader->stage == MESA_SHADER_VERTEX ||
-          shader->stage == MESA_SHADER_GEOMETRY ||
-          shader->stage == MESA_SHADER_FRAGMENT ||
-          shader->stage == MESA_SHADER_COMPUTE);
-
-   bool uses_sample_qualifier = false;
-   shader->info->inputs_read = 0;
-   foreach_list_typed(nir_variable, var, node, &shader->inputs) {
-      shader->info->inputs_read |= get_io_mask(var, shader->stage);
-      uses_sample_qualifier |= var->data.sample;
-   }
-
-   if (shader->stage == MESA_SHADER_FRAGMENT)
-      shader->info->fs.uses_sample_qualifier = uses_sample_qualifier;
-
-   /* TODO: Some day we may need to add stream support to NIR */
-   shader->info->outputs_written = 0;
-   foreach_list_typed(nir_variable, var, node, &shader->outputs)
-      shader->info->outputs_written |= get_io_mask(var, shader->stage);
-
-   shader->info->system_values_read = 0;
-   foreach_list_typed(nir_variable, var, node, &shader->system_values)
-      shader->info->system_values_read |= get_io_mask(var, shader->stage);
-
    shader->info->num_textures = 0;
    shader->info->num_images = 0;
    nir_foreach_variable(var, &shader->uniforms) {
@@ -162,6 +306,16 @@ nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
       }
    }
 
+   shader->info->inputs_read = 0;
+   shader->info->outputs_written = 0;
+   shader->info->outputs_read = 0;
+   shader->info->double_inputs_read = 0;
+   shader->info->patch_inputs_read = 0;
+   shader->info->patch_outputs_written = 0;
+   shader->info->system_values_read = 0;
+   if (shader->stage == MESA_SHADER_FRAGMENT) {
+      shader->info->fs.uses_sample_qualifier = false;
+   }
    nir_foreach_block(block, entrypoint) {
       gather_info_block(block, shader);
    }