glsl: Pass _mesa_glsl_parse_state into matching_signature and such.

During compilation, we'll use this to determine built-in availability.
The plan is to have a single shader containing every built-in in every
version of the language, but filter out the ones that aren't actually
available to the shader being compiled.

At link time, we don't actually need this filtering capability: we've
already imported prototypes for every built-in that the shader actually
calls, and they're flagged as is_builtin().  The linker doesn't import
any additional prototypes, so it won't pull in any unavailable
built-ins.  When resolving prototypes to function definitions, the
linker ensures the values of is_builtin() match, which means that a
shader can't trick the linker into importing the body of an unavailable
built-in by defining a suspiciously similar prototype.

In other words, during linking, we can just pass in NULL.  It will work
out fine.

Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Matt Turner <[email protected]>
Reviewed-by: Paul Berry <[email protected]>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/glsl/link_functions.cpp b/src/glsl/link_functions.cpp
index c5398f5ff04..9e96365e6de 100644
--- a/src/glsl/link_functions.cpp
+++ b/src/glsl/link_functions.cpp
@@ -113,7 +113,7 @@ public:
       }
 
       ir_function_signature *linked_sig =
-	 f->exact_matching_signature(&callee->parameters);
+	 f->exact_matching_signature(NULL, &callee->parameters);
       if ((linked_sig == NULL)
 	  || ((linked_sig != NULL)
 	      && (linked_sig->is_builtin() != ir->use_builtin))) {
@@ -288,7 +288,8 @@ find_matching_signature(const char *name, const exec_list *actual_parameters,
       if (f == NULL)
 	 continue;
 
-      ir_function_signature *sig = f->matching_signature(actual_parameters);
+      ir_function_signature *sig =
+         f->matching_signature(NULL, actual_parameters);
 
       if ((sig == NULL) || !sig->is_defined)
 	 continue;