Bug 1444604: Part 4: Construct FramePtrs from AbstractFramePtrs. r=jorendorff

--HG--
extra : rebase_source : 27cb8cb393ad666b38b320d9920021de16b74593
extra : histedit_source : ba96218ef2580dc2491e66137b961246068aa8fa

js/src/vm/Stack-inl.h

@@ -998,6 +998,25 @@ LiveSavedFrameCache::FramePtr::create(const FrameIter& iter)
     MOZ_CRASH("unexpected frame type");
 }
 
+/* static */ inline LiveSavedFrameCache::FramePtr
+LiveSavedFrameCache::FramePtr::create(AbstractFramePtr afp)
+{
+    MOZ_ASSERT(afp);
+
+    if (afp.isBaselineFrame()) {
+        js::jit::CommonFrameLayout *common = afp.asBaselineFrame()->framePrefix();
+        return FramePtr(common);
+    }
+    if (afp.isInterpreterFrame())
+        return FramePtr(afp.asInterpreterFrame());
+    if (afp.isWasmDebugFrame())
+        return FramePtr(afp.asWasmDebugFrame());
+    if (afp.isRematerializedFrame())
+        return FramePtr(afp.asRematerializedFrame());
+
+    MOZ_CRASH("unexpected frame type");
+}
+
 struct LiveSavedFrameCache::FramePtr::HasCachedMatcher {
     template<typename Frame>
     bool match(Frame* f) const { return f->hasCachedSavedFrame(); }

js/src/vm/Stack.h

@@ -1264,6 +1264,9 @@ class LiveSavedFrameCache
         // for its frame. Otherwise, return Nothing.
         static inline mozilla::Maybe<FramePtr> create(const FrameIter& iter);
 
+        // Construct a FramePtr from an AbstractFramePtr. This always succeeds.
+        static inline FramePtr create(AbstractFramePtr abstractFramePtr);
+
         inline bool hasCachedSavedFrame() const;
         inline void setHasCachedSavedFrame();