--- a/js/src/jit/IonFrames-inl.h
+++ b/js/src/jit/IonFrames-inl.h
@@ -75,24 +75,12 @@ GetTopBaselineFrame(JSContext *cx)
     MOZ_ASSERT(iter.type() == JitFrame_Exit);
     ++iter;
     if (iter.isBaselineStub())
         ++iter;
     MOZ_ASSERT(iter.isBaselineJS());
     return iter.baselineFrame();
 }
 
-inline JSScript *
-GetTopIonJSScript(JSContext *cx, void **returnAddrOut = nullptr)
-{
-    return GetTopIonJSScript(cx->mainThread().jitTop, returnAddrOut, SequentialExecution);
-}
-
-inline JSScript *
-GetTopIonJSScript(ForkJoinContext *cx, void **returnAddrOut = nullptr)
-{
-    return GetTopIonJSScript(cx->perThreadData->jitTop, returnAddrOut, ParallelExecution);
-}
-
 } // namespace jit
 } // namespace js
 
 #endif /* jit_IonFrames_inl_h */

--- a/js/src/jit/IonFrames.h
+++ b/js/src/jit/IonFrames.h
@@ -287,19 +287,19 @@ void UpdateJitActivationsForMinorGC(PerT
 static inline uint32_t
 MakeFrameDescriptor(uint32_t frameSize, FrameType type)
 {
     return (frameSize << FRAMESIZE_SHIFT) | type;
 }
 
 // Returns the JSScript associated with the topmost Ion frame.
 inline JSScript *
-GetTopIonJSScript(uint8_t *jitTop, void **returnAddrOut, ExecutionMode mode)
+GetTopIonJSScript(ThreadSafeContext *cx, void **returnAddrOut = nullptr)
 {
-    JitFrameIterator iter(jitTop, mode);
+    JitFrameIterator iter(cx);
     MOZ_ASSERT(iter.type() == JitFrame_Exit);
     ++iter;
 
     MOZ_ASSERT(iter.returnAddressToFp() != nullptr);
     if (returnAddrOut)
         *returnAddrOut = (void *) iter.returnAddressToFp();
 
     if (iter.isBaselineStub()) {