glsl: add helper for counting varyings

This will be used to get a count of the number of varying name
strings we are required to generate for use with the query api.

Reviewed-by: Dave Airlie <airlied@redhat.com>

src/compiler/glsl_types.cpp

@@ -1350,6 +1350,38 @@ glsl_type::uniform_locations() const
    }
 }
 
+unsigned
+glsl_type::varying_count() const
+{
+   unsigned size = 0;
+
+   switch (this->base_type) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+   case GLSL_TYPE_FLOAT:
+   case GLSL_TYPE_DOUBLE:
+   case GLSL_TYPE_BOOL:
+      return 1;
+
+   case GLSL_TYPE_STRUCT:
+   case GLSL_TYPE_INTERFACE:
+      for (unsigned i = 0; i < this->length; i++)
+         size += this->fields.structure[i].type->varying_count();
+      return size;
+   case GLSL_TYPE_ARRAY:
+      /* Don't count innermost array elements */
+      if (this->without_array()->is_record() ||
+          this->without_array()->is_interface() ||
+          this->fields.array->is_array())
+         return this->length * this->fields.array->varying_count();
+      else
+         return this->fields.array->varying_count();
+   default:
+      assert(!"unsupported varying type");
+      return 0;
+   }
+}
+
 bool
 glsl_type::can_implicitly_convert_to(const glsl_type *desired,
                                      _mesa_glsl_parse_state *state) const

src/compiler/glsl_types.h

@@ -326,6 +326,12 @@ struct glsl_type {
     */
    unsigned uniform_locations() const;
 
+   /**
+    * Used to count the number of varyings contained in the type ignoring
+    * innermost array elements.
+    */
+   unsigned varying_count() const;
+
    /**
     * Calculate the number of attribute slots required to hold this type
     *