Bugs

From JopWiki

Contents 1 checkcast/instanceof for arrays 2 bcfetch.vhd 3 TDMA arbiter 4 Array Exceptions 5 invokespecial 6 Stack overflow

[edit] checkcast/instanceof for arrays

instanceof/checkcast fail when testing arrays, e.g,

A[] a = new B[2];
boolean ok = a instanceof B[];

should return true, but returns false on JOP.

[edit] bcfetch.vhd

exception and int in the same cycle: int gets lost

[edit] TDMA arbiter

Memory pipelining over slot boundaries is not implemented. If an access of core 0 is at the last possible cycle within its slot, the next core's access (either pending or started at slot begin) is kept pending. Issue: WCET numbers are underestimates.

[edit] Array Exceptions

Upper bound exception comes too late -- in the next bytecode

arraylength does no null pointer check

[edit] invokespecial

is missing the null pointer check. Will be invoked on a null reference as it is statically linked.

[edit] Stack overflow

Stack overflow is detected by a = comparison. However, on a method invoke the SP is incremented by more than 1 and the stack overflow is not detected. Changing the test to >= will result in more than one generation of stack overflow. Would a state bit in the detection help?