[CFE] Fixes for instrumenter

Change-Id: Ib63140b2a64a9ab1a235d1b8e2e8872e13eecd34
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/448401
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>
diff --git a/pkg/front_end/tool/flame/instrumenter.dart b/pkg/front_end/tool/flame/instrumenter.dart
index 2884758..16f7732 100644
--- a/pkg/front_end/tool/flame/instrumenter.dart
+++ b/pkg/front_end/tool/flame/instrumenter.dart
@@ -247,7 +247,7 @@
     Set<String> procedureNamesWantedInFile =
         wanted[p.fileUri.pathSegments.last] ?? const {};
     return procedureNamesWantedInFile.contains(name) ||
-        !procedureNamesWantedInFile.contains("*");
+        procedureNamesWantedInFile.contains("*");
   }
 
   @override
diff --git a/pkg/front_end/tool/flame/instrumenter_lib.dart b/pkg/front_end/tool/flame/instrumenter_lib.dart
index 2b08302..7f18970 100644
--- a/pkg/front_end/tool/flame/instrumenter_lib.dart
+++ b/pkg/front_end/tool/flame/instrumenter_lib.dart
@@ -112,22 +112,18 @@
             "${withOutputInfo.names[enterProcedureNumber]}.",
           );
         }
-        bool foundMatch = false;
-        int steps = 1;
+        int? foundAt;
         for (int i = _activeStack.length - 2; i >= 0; i -= 2) {
-          steps++;
           if (_activeStack[i] == procedureNumber) {
-            foundMatch = true;
+            foundAt = i;
             break;
           }
         }
-        if (foundMatch) {
+        if (foundAt != null) {
           _activeStack.add(enterProcedureNumber);
           _activeStack.add(enterTicks);
-          enterProcedureNumber = _activeStack.removeAt(
-            _activeStack.length - steps * 2,
-          );
-          enterTicks = _activeStack.removeAt(_activeStack.length - steps * 2);
+          enterProcedureNumber = _activeStack.removeAt(foundAt);
+          enterTicks = _activeStack.removeAt(foundAt);
           assert(enterProcedureNumber != procedureNumber);
         } else {
           throw "Mismatching enter/exit with no matching "