diff --git a/js/src/gdb/mozilla/unwind.py b/js/src/gdb/mozilla/unwind.py
index 4e7ab91f0679..6020c2d6b40a 100644
--- a/js/src/gdb/mozilla/unwind.py
+++ b/js/src/gdb/mozilla/unwind.py
@@ -40,8 +40,6 @@ SizeOfFramePrefix = {
     'JitFrame_BaselineJS': 'JitFrameLayout',
     'JitFrame_BaselineStub': 'BaselineStubFrameLayout',
     'JitFrame_IonStub': 'JitStubFrameLayout',
-    # Technically EntryFrameLayout, but that doesn't wind up in the
-    # debuginfo because there are no uses of it.
     'JitFrame_Entry': 'JitFrameLayout',
     'JitFrame_Rectifier': 'RectifierFrameLayout',
     'JitFrame_IonAccessorIC': 'IonAccessorICFrameLayout',
diff --git a/js/src/jit/JitFrames.h b/js/src/jit/JitFrames.h
index 2b8df56aabb9..e165a7d52b96 100644
--- a/js/src/jit/JitFrames.h
+++ b/js/src/jit/JitFrames.h
@@ -95,10 +95,11 @@ ScriptFromCalleeToken(CalleeToken token)
 // to. The exact mechanism in which frames are laid out is architecture
 // dependent.
 //
-// Two special frame types exist. Entry frames begin an ion activation, and
-// therefore there is exactly one per activation of jit::Cannon. Exit frames
-// are necessary to leave JIT code and enter C++, and thus, C++ code will
-// always begin iterating from the topmost exit frame.
+// Two special frame types exist:
+// - Entry frames begin a JitActivation, and therefore there is exactly one
+// per activation of EnterIon or EnterBaseline. These reuse JitFrameLayout.
+// - Exit frames are necessary to leave JIT code and enter C++, and thus,
+// C++ code will always begin iterating from the topmost exit frame.
 
 class LSafepoint;
 
@@ -438,15 +439,6 @@ class JitFrameLayout : public CommonFrameLayout
     }
 };
 
-// this is the layout of the frame that is used when we enter Ion code from platform ABI code
-class EntryFrameLayout : public JitFrameLayout
-{
-  public:
-    static inline size_t Size() {
-        return sizeof(EntryFrameLayout);
-    }
-};
-
 class RectifierFrameLayout : public JitFrameLayout
 {
   public: