glsl: Simplify the built-in function linking code.

Previously, we stored an array of up to 16 additional shaders to link,
as well as a count of how many each shader actually needed.

Since the built-in functions rewrite, all the built-ins are stored in a
single shader.  So all we need is a boolean indicating whether a shader
needs to link against built-ins or not.

During linking, we can avoid creating the temporary array if none of the
shaders being linked need built-ins.  Otherwise, it's simply a copy of
the array that has one additional element.  This is much simpler.

This patch saves approximately 128 bytes of memory per gl_shader object.

Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>

2 files changed, 2 insertions, 4 deletions

diff --git a/src/mesa/main/ff_fragment_shader.cpp b/src/mesa/main/ff_fragment_shader.cpp
index 01edd3ff8af..0d75702835e 100644
--- a/src/mesa/main/ff_fragment_shader.cpp
+++ b/src/mesa/main/ff_fragment_shader.cpp
@@ -1344,7 +1344,7 @@ create_new_program(struct gl_context *ctx, struct state_key *key)
 
    p.shader->CompileStatus = true;
    p.shader->Version = state->language_version;
-   p.shader->num_builtins_to_link = state->num_builtins_to_link;
+   p.shader->uses_builtin_functions = state->uses_builtin_functions;
    p.shader_program->Shaders =
       (gl_shader **)malloc(sizeof(*p.shader_program->Shaders));
    p.shader_program->Shaders[0] = p.shader;
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index b4b432f4023..05fb3d59f0b 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2352,9 +2352,7 @@ struct gl_shader
    struct exec_list *ir;
    struct glsl_symbol_table *symbols;
 
-   /** Shaders containing built-in functions that are used for linking. */
-   struct gl_shader *builtins_to_link[16];
-   unsigned num_builtins_to_link;
+   bool uses_builtin_functions;
 
    /**
     * Geometry shader state from GLSL 1.50 layout qualifiers.