[rvm-research] question regarding raw memory access

Hi All,

I am trying to access the bytes that make up an object using the utility function Magic.getByteAtOffset(Object, Offset). I am doing this during a GC pause after all edges in an object are processed in scanObject(ObjectReference). This procedure is useful, for instance, in creating a unique hash for each object. Given that idx is of type int ranging from 0 to sizeof_object_minus_one, offset is initialized to zero, and objectRef is of type ObjectReference, I use the following statement to access the bytes stored in each object in memory. 

byte next_byte = Magic.getByteAtOffset(objectRef.toObject(), offset.plus(idx));

This statement results in a hardware trap (after a few GC pauses). Is this the correct and safe approach to access raw memory in this part of JikesRVM (SpecializedScanMethod::scanObject(ObjectReference))?

Regards,
Shoaib.
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