From: Ian Romanick <ian.d.romanick@intel.com>
Date: Tue, 8 Jun 2010 01:53:06 +0000 (-0700)
Subject: Don't process empty shaders
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=15d162d7b1ebe09b0bdaf43194529f9ef995c623;p=mesa.git

Don't process empty shaders

Some valid shaders, such as 'precision highp float;', evaluate to
empty sets of instructions.  This causes some of the optimization
stages to enter infinite loops.  Instead, don't bother processing the
empty ones.
---

diff --git a/glsl_parser_extras.cpp b/glsl_parser_extras.cpp
index afce9d9c348..f6b30289ce3 100644
--- a/glsl_parser_extras.cpp
+++ b/glsl_parser_extras.cpp
@@ -737,7 +737,8 @@ main(int argc, char **argv)
 	 ast->print();
       }
 
-      _mesa_ast_to_hir(&instructions, &state);
+      if (!state.translation_unit.is_empty())
+	 _mesa_ast_to_hir(&instructions, &state);
    } else {
       /* FINISHME: We should initialize this to the max GLSL version supported
        * FINISHME: by the driver.  At the moment, we don't know what that is.
@@ -748,7 +749,7 @@ main(int argc, char **argv)
    }
 
    /* Optimization passes */
-   if (!state.error) {
+   if (!state.error && !instructions.is_empty()) {
       bool progress;
       do {
 	 progress = false;