[Mesa-dev] [PATCH 1/3] glsl_parser_extra: Add utility to copy symbols between symbol tables

[Eduardo Lima Mitev]

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 input and output 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 built-in input and output blocks too.

The function will be used in a subsequent patch.
---
 src/compiler/glsl/glsl_parser_extras.cpp | 35 ++++++++++++++++++++++++++++++++
 src/compiler/glsl/glsl_parser_extras.h   |  5 +++++
 2 files changed, 40 insertions(+)

diff --git a/src/compiler/glsl/glsl_parser_extras.cpp b/src/compiler/glsl/glsl_parser_extras.cpp
index 3d2fc1429b4..9f6ab801b13 100644
--- a/src/compiler/glsl/glsl_parser_extras.cpp
+++ b/src/compiler/glsl/glsl_parser_extras.cpp
@@ -1838,6 +1838,41 @@ set_shader_inout_layout(struct gl_shader *shader,
    }
 }
 
+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);
+
+            const glsl_type *iface = var->get_interface_type();
+            if (iface && strstr(iface->name, "gl_") == iface->name) {
+               const glsl_type *entry =
+                  src->get_interface(iface->name, ir_var_shader_in);
+               if (entry)
+                  dest->add_interface(iface->name, entry, ir_var_shader_in);
+
+               entry = src->get_interface(iface->name, ir_var_shader_out);
+               if (entry)
+                  dest->add_interface(iface->name, entry, ir_var_shader_out);
+            }
+         }
+         break;
+      }
+      default:
+         break;
+      }
+   }
+}
+
 extern "C" {
 
 static void
diff --git a/src/compiler/glsl/glsl_parser_extras.h b/src/compiler/glsl/glsl_parser_extras.h
index 424cab5023c..cce69e51767 100644
--- a/src/compiler/glsl/glsl_parser_extras.h
+++ b/src/compiler/glsl/glsl_parser_extras.h
@@ -921,6 +921,11 @@ 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
-- 
2.11.0