Remove dead code assignments and variable declarations.

This pass only works on assignments where the variable is never
referenced.  There is no code flow analysis, so it can't do a better
job of avoiding redundant assignments.

For now, the optimizer only does do_dead_code_unlinked(), so it won't
trim the builtin variable list or initializers outside of the scope of
functions.  This is because we don't have the visibility into other
functions that might get linked in in order to eliminate work on
global variables.

1 files changed, 2 insertions, 0 deletions

diff --git a/glsl_parser_extras.cpp b/glsl_parser_extras.cpp
index 455bf0c7a4..f7ee891eeb 100644
--- a/glsl_parser_extras.cpp
+++ b/glsl_parser_extras.cpp
@@ -35,6 +35,7 @@
 #include "glsl_parser_extras.h"
 #include "glsl_parser.h"
 #include "ir_constant_folding.h"
+#include "ir_dead_code.h"
 #include "ir_function_inlining.h"
 #include "ir_if_simplification.h"
 #include "ir_print_visitor.h"
@@ -761,6 +762,7 @@ main(int argc, char **argv)
 
 	 progress = do_function_inlining(&instructions) || progress;
 	 progress = do_if_simplification(&instructions) || progress;
+	 progress = do_dead_code_unlinked(&instructions) || progress;
 
 	 /* Constant folding */
 	 ir_constant_folding_visitor constant_folding;