[syntax tree]: debugging phi-nodes simplification

include/ir/value.h

@@ -86,6 +86,7 @@ public:
 
   // Utils
   void replace_all_uses_with(value *target);
+  void replace_uses_of_with(value *before, value *after);
 
 private:
   std::vector<use> ops_;

lib/ir/value.cpp

@@ -1,4 +1,5 @@
 #include "ir/value.h"
+#include <iostream>
 #include <cassert>
 
 namespace tdl{
@@ -64,10 +65,18 @@ unsigned user::get_num_operands() const {
 }
 
 void user::replace_all_uses_with(value *target) {
-  for(use &u: uses_){
-    u.set(target);
+  for(use &u: uses_)
+  if(auto *usr = dynamic_cast<user*>(u.get())){
+    std::cout << "replacing " << this << " by " << target << " in " << usr << std::endl;
+    usr->replace_uses_of_with(this, target);
   }
 }
 
+void user::replace_uses_of_with(value *before, value *after) {
+  for(use &u: ops_)
+    if(u.get() == before)
+      u.set(after);
+}
+
 }
 }