Bug 928889: Baseline: Return the correct *pc when in prologue, r=jandem

js/src/jit/IonFrames.cpp

@@ -184,9 +184,10 @@ IonFrameIterator::baselineScriptAndPc(JSScript **scriptRes, jsbytecode **pcRes)
         *scriptRes = script;
     uint8_t *retAddr = returnAddressToFp();
     if (pcRes) {
-        // If the return address is into the prologue entry addr, then assume PC 0.
+        // If the return address is into the prologue entry address, then assume start
+        // of script.
         if (retAddr == script->baselineScript()->prologueEntryAddr()) {
-            *pcRes = 0;
+            *pcRes = script->code;
             return;
         }