glsl/ir: add subroutine information storage to ir_function (v1.1)

We need to store two sets of info into the ir_function,
if this is a function definition with a subroutine list
(subroutine_def) or if it a subroutine prototype.

v1.1: add some more documentation.

Reviewed-by: Chris Forbes <chrisf@ijw.co.nz>
Signed-off-by: Dave Airlie <airlied@redhat.com>

src/glsl/ir.cpp

@@ -1855,6 +1855,7 @@ static void
 steal_memory(ir_instruction *ir, void *new_ctx)
 {
    ir_variable *var = ir->as_variable();
+   ir_function *fn = ir->as_function();
    ir_constant *constant = ir->as_constant();
    if (var != NULL && var->constant_value != NULL)
       steal_memory(var->constant_value, ir);
@@ -1862,6 +1863,9 @@ steal_memory(ir_instruction *ir, void *new_ctx)
    if (var != NULL && var->constant_initializer != NULL)
       steal_memory(var->constant_initializer, ir);
 
+   if (fn != NULL && fn->subroutine_types)
+      ralloc_steal(new_ctx, fn->subroutine_types);
+
    /* The components of aggregate constants are not visited by the normal
     * visitor, so steal their values by hand.
     */

src/glsl/ir.h

@@ -1126,6 +1126,21 @@ public:
     * List of ir_function_signature for each overloaded function with this name.
     */
    struct exec_list signatures;
+
+   /**
+    * is this function a subroutine type declaration
+    * e.g. subroutine void type1(float arg1);
+    */
+   bool is_subroutine;
+
+   /**
+    * is this function associated to a subroutine type
+    * e.g. subroutine (type1, type2) function_name { function_body };
+    * would have num_subroutine_types 2,
+    * and pointers to the type1 and type2 types.
+    */
+   int num_subroutine_types;
+   const struct glsl_type **subroutine_types;
 };
 
 inline const char *ir_function_signature::function_name() const

src/glsl/ir_clone.cpp

@@ -267,6 +267,12 @@ ir_function::clone(void *mem_ctx, struct hash_table *ht) const
 {
    ir_function *copy = new(mem_ctx) ir_function(this->name);
 
+   copy->is_subroutine = this->is_subroutine;
+   copy->num_subroutine_types = this->num_subroutine_types;
+   copy->subroutine_types = ralloc_array(mem_ctx, const struct glsl_type *, copy->num_subroutine_types);
+   for (int i = 0; i < copy->num_subroutine_types; i++)
+     copy->subroutine_types[i] = this->subroutine_types[i];
+
    foreach_in_list(const ir_function_signature, sig, &this->signatures) {
       ir_function_signature *sig_copy = sig->clone(mem_ctx, ht);
       copy->add_signature(sig_copy);

src/glsl/ir_print_visitor.cpp

@@ -231,7 +231,7 @@ void ir_print_visitor::visit(ir_function_signature *ir)
 
 void ir_print_visitor::visit(ir_function *ir)
 {
-   fprintf(f, "(function %s\n", ir->name);
+   fprintf(f, "(%s function %s\n", ir->is_subroutine ? "subroutine" : "", ir->name);
    indentation++;
    foreach_in_list(ir_function_signature, sig, &ir->signatures) {
       indent();