--- a/src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp	Mon Jul 06 23:11:37 2020 -0700
+++ b/src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp	Tue Apr 21 10:35:53 2020 +0200
@@ -65,9 +65,7 @@
 }
 
 void ShenandoahBarrierSetC2State::remove_enqueue_barrier(ShenandoahEnqueueBarrierNode * n) {
-  if (_enqueue_barriers->contains(n)) {
-    _enqueue_barriers->remove(n);
-  }
+  _enqueue_barriers->remove_if_existing(n);
 }
 
 int ShenandoahBarrierSetC2State::load_reference_barriers_count() const {

--- a/src/hotspot/share/opto/compile.hpp	Mon Jul 06 23:11:37 2020 -0700
+++ b/src/hotspot/share/opto/compile.hpp	Tue Apr 21 10:35:53 2020 +0200
@@ -667,23 +667,20 @@
     assert(!_macro_nodes->contains(n), "duplicate entry in expand list");
     _macro_nodes->append(n);
   }
-  void remove_macro_node(Node * n) {
-    // this function may be called twice for a node so check
-    // that the node is in the array before attempting to remove it
-    if (_macro_nodes->contains(n))
-      _macro_nodes->remove(n);
+  void remove_macro_node(Node* n) {
+    // this function may be called twice for a node so we can only remove it
+    // if it's still existing.
+    _macro_nodes->remove_if_existing(n);
     // remove from _predicate_opaqs list also if it is there
-    if (predicate_count() > 0 && _predicate_opaqs->contains(n)){
-      _predicate_opaqs->remove(n);
+    if (predicate_count() > 0) {
+      _predicate_opaqs->remove_if_existing(n);
     }
   }
-  void add_expensive_node(Node * n);
-  void remove_expensive_node(Node * n) {
-    if (_expensive_nodes->contains(n)) {
-      _expensive_nodes->remove(n);
-    }
+  void add_expensive_node(Node* n);
+  void remove_expensive_node(Node* n) {
+    _expensive_nodes->remove_if_existing(n);
   }
-  void add_predicate_opaq(Node * n) {
+  void add_predicate_opaq(Node* n) {
     assert(!_predicate_opaqs->contains(n), "duplicate entry in predicate opaque1");
     assert(_macro_nodes->contains(n), "should have already been in macro list");
     _predicate_opaqs->append(n);
@@ -692,9 +689,7 @@
   // Range check dependent CastII nodes that can be removed after loop optimizations
   void add_range_check_cast(Node* n);
   void remove_range_check_cast(Node* n) {
-    if (_range_check_casts->contains(n)) {
-      _range_check_casts->remove(n);
-    }
+    _range_check_casts->remove_if_existing(n);
   }
   Node* range_check_cast_node(int idx) const { return _range_check_casts->at(idx);  }
   int   range_check_cast_count()       const { return _range_check_casts->length(); }
@@ -703,9 +698,7 @@
 
   void add_opaque4_node(Node* n);
   void remove_opaque4_node(Node* n) {
-    if (_opaque4_nodes->contains(n)) {
-      _opaque4_nodes->remove(n);
-    }
+    _opaque4_nodes->remove_if_existing(n);
   }
   Node* opaque4_node(int idx) const { return _opaque4_nodes->at(idx);  }
   int   opaque4_count()       const { return _opaque4_nodes->length(); }

--- a/src/hotspot/share/prims/jvmtiRawMonitor.hpp	Mon Jul 06 23:11:37 2020 -0700
+++ b/src/hotspot/share/prims/jvmtiRawMonitor.hpp	Tue Apr 21 10:35:53 2020 +0200
@@ -137,12 +137,7 @@
 
   // Return false if monitor is not found in the list.
   static bool exit(JvmtiRawMonitor* monitor) {
-    if (monitors()->contains(monitor)) {
-      monitors()->remove(monitor);
-      return true;
-    } else {
-      return false;
-    }
+    return monitors()->remove_if_existing(monitor);
   }
 
   static void transition_raw_monitors();

--- a/src/hotspot/share/utilities/growableArray.hpp	Mon Jul 06 23:11:37 2020 -0700
+++ b/src/hotspot/share/utilities/growableArray.hpp	Tue Apr 21 10:35:53 2020 +0200
@@ -207,21 +207,31 @@
     return -1;
   }
 
+  // Order preserving remove operations.
+
   void remove(const E& elem) {
-    for (int i = 0; i < _len; i++) {
-      if (_data[i] == elem) {
-        for (int j = i + 1; j < _len; j++) _data[j-1] = _data[j];
-        _len--;
-        return;
-      }
-    }
+    // Assuming that element does exist.
+    bool removed = remove_if_existing(elem);
+    if (removed) return;
     ShouldNotReachHere();
   }
 
-  // The order is preserved.
+  bool remove_if_existing(const E& elem) {
+    // Returns TRUE if elem is removed.
+    for (int i = 0; i < _len; i++) {
+      if (_data[i] == elem) {
+        remove_at(i);
+        return true;
+      }
+    }
+    return false;
+  }
+
   void remove_at(int index) {
     assert(0 <= index && index < _len, "illegal index");
-    for (int j = index + 1; j < _len; j++) _data[j-1] = _data[j];
+    for (int j = index + 1; j < _len; j++) {
+      _data[j-1] = _data[j];
+    }
     _len--;
   }