Request for reviews (S): 7063674: Wrong results from basic comparisons after calls to Long.bitCount(long)
christian.thalinger at oracle.com
Mon Jun 11 15:35:53 PDT 2012
7063674: Wrong results from basic comparisons after calls to Long.bitCount(long)
We are scheduling popcnt instructions between compare and branch/conditional
move instructions because AD instructs are not defined to kill flags.
But the Intel Instruction Set Reference says for POPCNT:
OF, SF, ZF, AF, CF, PF are all cleared. ZF is set if SRC = 0, otherwise ZF is cleared
The fix is to kill the flags in instructs that are using popcnt instructions.
Tested with test case of CR.
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