From 21f957195a740726806b2ae3162cab0367361cfb Mon Sep 17 00:00:00 2001
From: Nathan Braswell <miloignis@gmail.com>
Date: Fri, 20 Jan 2017 01:31:28 -0500
Subject: [PATCH] Fix dreferencing function_call refs. Now need to make sure
 new pass method works with defer_lower, which currently does very crazy defer
 double stack chains

---
 stdlib/ref_lower.krak | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/stdlib/ref_lower.krak b/stdlib/ref_lower.krak
index 6c66841..884e386 100644
--- a/stdlib/ref_lower.krak
+++ b/stdlib/ref_lower.krak
@@ -38,7 +38,7 @@ fun remove_ref(t: *type) {
 
 fun ref_lower(name_ast_map: *map<string, pair<*tree<symbol>,*ast_node>>, ast_to_syntax: *map<*ast_node, *tree<symbol>>) {
     var remove_ref_type_set = set<pair<string,*type>>()
-    var modify_identifier_set = set<pair<*ast_node, *ast_node>>()
+    var modify_reference_use_set = set<pair<*ast_node, *ast_node>>()
     var modify_return_set = set<*ast_node>()
     var visited = set<*ast_node>()
     name_ast_map->for_each(fun(name: string, syntax_ast_pair: pair<*tree<symbol>,*ast_node>) {
@@ -46,7 +46,7 @@ fun ref_lower(name_ast_map: *map<string, pair<*tree<symbol>,*ast_node>>, ast_to_
             match(*node) {
                 ast_node::identifier(backing) {
                     if (backing.type->is_ref)
-                        modify_identifier_set.add(make_pair(node, parent_chain->top()))
+                        modify_reference_use_set.add(make_pair(node, parent_chain->top()))
                     if (has_ref_inside(backing.type)) {
                         remove_ref_type_set.add(make_pair("identifier: " + backing.name, backing.type))
                     }
@@ -65,6 +65,9 @@ fun ref_lower(name_ast_map: *map<string, pair<*tree<symbol>,*ast_node>>, ast_to_
                     for (var i = 0; i < func_type_params.size; i++;)
                         if (func_type_params[i]->is_ref)
                             backing.parameters[i] = make_operator_call("&", vector(backing.parameters[i]))
+                    // add the function call to the modify_reference_use set if the function returns a ref
+                    if (get_ast_type(backing.func)->return_type->is_ref)
+                        modify_reference_use_set.add(make_pair(node, parent_chain->top()))
                 }
                 ast_node::return_statement(backing) {
                     // check to see if it's returning a ref, if so add in the &
@@ -81,15 +84,15 @@ fun ref_lower(name_ast_map: *map<string, pair<*tree<symbol>,*ast_node>>, ast_to_
         remove_ref(t)
         println("after" + p.first + ": " + t->to_string())
     })
-    modify_identifier_set.for_each(fun(p: pair<*ast_node, *ast_node>) {
+    modify_reference_use_set.for_each(fun(p: pair<*ast_node, *ast_node>) {
         // if we haven't modified it's indirection yet
-        if (p.first->identifier.type->is_ref) {
+        if (is_identifier(p.first) && p.first->identifier.type->is_ref) {
             // remove ref, add 1 to indirection
             p.first->identifier.type = p.first->identifier.type->clone_with_increased_indirection(1, false);
         }
         // note that we definitly want to replace the type for unused parameters, but we don't want to add the * for paramters
         // in function declarations or declaration statements
-        if (!is_function(p.second) && !is_declaration_statement(p.second))
+        if (!is_identifier(p.first) || (!is_function(p.second) && !is_declaration_statement(p.second)))
             replace_with_in(p.first, make_operator_call("*", vector(p.first)), p.second);
     })
     modify_return_set.for_each(fun(r: *ast_node) {