Bug 1172076 - Improve js::DumpBacktrace to include raw frame pointers and types. r=jandem

js/src/jsobj.cpp

@@ -3511,8 +3511,15 @@ js::DumpBacktrace(JSContext* cx)
         const char* filename = JS_GetScriptFilename(i.script());
         unsigned line = PCToLineNumber(i.script(), i.pc());
         JSScript* script = i.script();
-        sprinter.printf("#%d %14p   %s:%d (%p @ %d)\n",
-                        depth, (i.isJit() ? 0 : i.interpFrame()), filename, line,
+        char frameType =
+            i.isInterp() ? 'i' :
+            i.isBaseline() ? 'b' :
+            i.isIon() ? 'I' :
+            i.isAsmJS() ? 'A' :
+            '?';
+
+        sprinter.printf("#%d %14p %c   %s:%d (%p @ %d)\n",
+                        depth, i.rawFramePtr(), frameType, filename, line,
                         script, script->pcToOffset(i.pc()));
     }
     fprintf(stdout, "%s", sprinter.string());

js/src/vm/Stack.cpp

@@ -853,6 +853,21 @@ FrameIter::copyDataAsAbstractFramePtr() const
     return frame;
 }
 
+void*
+FrameIter::rawFramePtr() const
+{
+    switch (data_.state_) {
+      case DONE:
+      case ASMJS:
+        return nullptr;
+      case JIT:
+        return data_.jitFrames_.fp();
+      case INTERP:
+        return interpFrame();
+    }
+    MOZ_CRASH("Unexpected state");
+}
+
 JSCompartment*
 FrameIter::compartment() const
 {

js/src/vm/Stack.h

@@ -2040,6 +2040,9 @@ class FrameIter
     // This can only be called when isPhysicalIonFrame():
     inline jit::CommonFrameLayout* physicalIonFrame() const;
 
+    // This is used to provide a raw interface for debugging.
+    void* rawFramePtr() const;
+
   private:
     Data data_;
     jit::InlineFrameIterator ionInlineFrames_;