linker: Implement first bits of intrastage linking
This currently involves an ugly hack so that every link doesn't result
in all the built-in functions showing up as multiply defined. As soon
as the built-in functions are stored in a separate compilation unit,
ir_function_signature::is_built_in can be removed.
diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index 04b4efd..3d8f24b 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -473,8 +473,64 @@
struct gl_shader **shader_list,
unsigned num_shaders)
{
- (void) prog;
- assert(num_shaders == 1);
+ /* Check that global variables defined in multiple shaders are consistent.
+ */
+ if (!cross_validate_globals(prog, shader_list, num_shaders, false))
+ return NULL;
+
+ /* Check that there is only a single definition of each function signature
+ * across all shaders.
+ */
+ for (unsigned i = 0; i < (num_shaders - 1); i++) {
+ foreach_list(node, shader_list[i]->ir) {
+ ir_function *const f = ((ir_instruction *) node)->as_function();
+
+ if (f == NULL)
+ continue;
+
+ for (unsigned j = i + 1; j < num_shaders; j++) {
+ ir_function *const other =
+ shader_list[j]->symbols->get_function(f->name);
+
+ /* If the other shader has no function (and therefore no function
+ * signatures) with the same name, skip to the next shader.
+ */
+ if (other == NULL)
+ continue;
+
+ foreach_iter (exec_list_iterator, iter, *f) {
+ ir_function_signature *sig =
+ (ir_function_signature *) iter.get();
+
+ if (!sig->is_defined || sig->is_built_in)
+ continue;
+
+ ir_function_signature *other_sig =
+ other->exact_matching_signature(& sig->parameters);
+
+ if ((other_sig != NULL) && other_sig->is_defined
+ && !other_sig->is_built_in) {
+ linker_error_printf(prog,
+ "function `%s' is multiply defined",
+ f->name);
+ return NULL;
+ }
+ }
+ }
+ }
+ }
+
+ /* Find the shader that defines main, and make a clone of it.
+ *
+ * Starting with the clone, search for undefined references. If one is
+ * found, find the shader that defines it. Clone the reference and add
+ * it to the shader. Repeat until there are no undefined references or
+ * until a reference cannot be resolved.
+ */
+
+
+ /* Resolve initializers for global variables in the linked shader.
+ */
gl_shader *const linked = _mesa_new_shader(NULL, 0, shader_list[0]->Type);
linked->ir = new(linked) exec_list;