gistfile1.diff

diff --git a/js/src/ion/Ion.cpp b/js/src/ion/Ion.cpp
index 8766100..b6c667c 100644
--- a/js/src/ion/Ion.cpp
+++ b/js/src/ion/Ion.cpp
@@ -1428,7 +1428,8 @@ Compile(JSContext *cx, HandleScript script, HandleFunction fun, jsbytecode *osrP
         return Method_Compiled;
     }
 
-    if (executionMode == SequentialExecution) {
+    switch (executionMode) {
+      case SequentialExecution:
         if (cx->methodJitEnabled) {
             // If JM is enabled we use getUseCount instead of incUseCount to avoid
             // bumping the use count twice.
@@ -1439,6 +1440,12 @@ Compile(JSContext *cx, HandleScript script, HandleFunction fun, jsbytecode *osrP
             if (script->incUseCount() < js_IonOptions.usesBeforeCompileNoJaeger)
                 return Method_Skipped;
         }
+        break;
+      case ParallelExecution:
+        // Bump the use count, but do not use it as a heuristic here.
+        if (!cx->methodJitEnabled)
+            script->incUseCount();
+        break;
     }
 
     AbortReason reason = IonCompile(cx, script, fun, osrPc, constructing, compileContext);