8353276: C2: simplify PhaseMacroExpand::opt_bits_test

Reviewed-by: chagedorn, thartmann

Author: Saranya Natarajan

src/hotspot/share/opto/macro.cpp

@@ -93,14 +93,8 @@ void PhaseMacroExpand::migrate_outs(Node *old, Node *target) {
   assert(old->outcnt() == 0, "all uses must be deleted");
 }
 
-Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) {
-  Node* cmp;
-  if (mask != 0) {
-    Node* and_node = transform_later(new AndXNode(word, MakeConX(mask)));
-    cmp = transform_later(new CmpXNode(and_node, MakeConX(bits)));
-  } else {
-    cmp = word;
-  }
+Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word) {
+  Node* cmp = word;
   Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne));
   IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN );
   transform_later(iff);
@@ -111,13 +105,8 @@ Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node*
   // Fast path not-taken, i.e. slow path
   Node *slow_taken = transform_later(new IfTrueNode(iff));
 
-  if (return_fast_path) {
-    region->init_req(edge, slow_taken); // Capture slow-control
-    return fast_taken;
-  } else {
     region->init_req(edge, fast_taken); // Capture fast-control
     return slow_taken;
-  }
 }
 
 //--------------------copy_predefined_input_for_runtime_call--------------------
@@ -2220,7 +2209,7 @@ void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
   mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
 
   // Optimize test; set region slot 2
-  slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0);
+  slow_path = opt_bits_test(ctrl, region, 2, flock);
   mem_phi->init_req(2, mem);
 
   // Make slow path call
@@ -2281,7 +2270,7 @@ void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) {
   FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box );
   funlock = transform_later( funlock )->as_FastUnlock();
   // Optimize test; set region slot 2
-  Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0);
+  Node *slow_path = opt_bits_test(ctrl, region, 2, funlock);
   Node *thread = transform_later(new ThreadLocalNode());
 
   CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(),

src/hotspot/share/opto/macro.hpp

@@ -182,7 +182,7 @@ class PhaseMacroExpand : public Phase {
 
   int replace_input(Node *use, Node *oldref, Node *newref);
   void migrate_outs(Node *old, Node *target);
-  Node* opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path = false);
+  Node* opt_bits_test(Node* ctrl, Node* region, int edge, Node* word);
   void copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call);
   CallNode* make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type, address slow_call,
                            const char* leaf_name, Node* slow_path, Node* parm0, Node* parm1,