glsl_parser_extra: Add utility to copy symbols between symbol tables

Some symbols gathered in the symbols table during parsing are needed
later for the compile and link stages, so they are moved along the
process. Currently, only functions and non-temporary variables are
copied between symbol tables. However, the built-in gl_PerVertex
interface blocks are also needed during the linking stage (the last
step), to match re-declared blocks of inter-stage shaders.

This patch adds a new utility function that will factorize current code
that copies functions and variables between two symbol tables, and in
addition will copy explicitly declared gl_PerVertex blocks too.

The function will be used in a subsequent patch.

v2 (Neil Roberts):
Allow the src symbol table to be NULL and explicitly copy the
gl_PerVertex symbols in case they are not referenced in the exec_list.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Eduardo Lima Mitev <elima@igalia.com>
Signed-off-by: Neil Roberts <nroberts@igalia.com>

diff --git a/src/compiler/glsl/glsl_parser_extras.cpp b/src/compiler/glsl/glsl_parser_extras.cpp
index 94ceb5eb873f63f65fdbbd6a4b5f6502718d1f87..97c7b4d7820040b9122cd981e306ff7b1be3e081 100644 (file)
--- a/src/compiler/glsl/glsl_parser_extras.cpp
+++ b/src/compiler/glsl/glsl_parser_extras.cpp
@@ -1852,6 +1852,49 @@ set_shader_inout_layout(struct gl_shader *shader,
    shader->bound_image = state->bound_image_specified;
 }
 
+/* src can be NULL if only the symbols found in the exec_list should be
+ * copied
+ */
+void
+_mesa_glsl_copy_symbols_from_table(struct exec_list *shader_ir,
+                                   struct glsl_symbol_table *src,
+                                   struct glsl_symbol_table *dest)
+{
+   foreach_in_list (ir_instruction, ir, shader_ir) {
+      switch (ir->ir_type) {
+      case ir_type_function:
+         dest->add_function((ir_function *) ir);
+         break;
+      case ir_type_variable: {
+         ir_variable *const var = (ir_variable *) ir;
+
+         if (var->data.mode != ir_var_temporary)
+            dest->add_variable(var);
+         break;
+      }
+      default:
+         break;
+      }
+   }
+
+   if (src != NULL) {
+      /* Explicitly copy the gl_PerVertex interface definitions because these
+       * are needed to check they are the same during the interstage link.
+       * They can’t necessarily be found via the exec_list because the members
+       * might not be referenced. The GL spec still requires that they match
+       * in that case.
+       */
+      const glsl_type *iface =
+         src->get_interface("gl_PerVertex", ir_var_shader_in);
+      if (iface)
+         dest->add_interface(iface->name, iface, ir_var_shader_in);
+
+      iface = src->get_interface("gl_PerVertex", ir_var_shader_out);
+      if (iface)
+         dest->add_interface(iface->name, iface, ir_var_shader_out);
+   }
+}
+
 extern "C" {
 
 static void

diff --git a/src/compiler/glsl/glsl_parser_extras.h b/src/compiler/glsl/glsl_parser_extras.h
index fb358130878da9cb910bab9ddeffd4bd1482e789..2e98bc72e744eb97b3885789d507509fc2e26960 100644 (file)
--- a/src/compiler/glsl/glsl_parser_extras.h
+++ b/src/compiler/glsl/glsl_parser_extras.h
@@ -948,6 +948,11 @@ extern int glcpp_preprocess(void *ctx, const char **shader, char **info_log,
 extern void _mesa_destroy_shader_compiler(void);
 extern void _mesa_destroy_shader_compiler_caches(void);
 
+extern void
+_mesa_glsl_copy_symbols_from_table(struct exec_list *shader_ir,
+                                   struct glsl_symbol_table *src,
+                                   struct glsl_symbol_table *dest);
+
 #ifdef __cplusplus
 }
 #endif