And in order to avoid a double dereference in the dispatcher, directly store
the normalEntry in the map.
The index to the block map becomes ((((DR<<1) | IR) << 30) | (address >> 2)).
This has been chosen since the msr bits change less often than the address,
thus we keep nearby entries together.
Also do not call the C dispatcher in case the assembly dispatcher didn't
find a block, since it wouldn't find a block either due to the 1:1 mapping,
except when falling back to the non shm segment lookup table.
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