If we unwind a stack frame for a VM_DynamicBridge method, then we must restore some of the registers saved in the dynamic bridge frame. This is not done on either of the platforms (PPC or IA32). Restoring the volatiles is probably not actually required (since the caller would have expected them to get killed anyways), but we must restore the nonvolatiles. The code to look at is VM_BaselineExceptionDeliverer.unwindStackFrame on both platforms. See SF: https://sourceforge.net/tracker/index.php?func=detail&aid=1147172&group_id=128805&atid=712768