We have seen failures on AIX while running java/util/zip/ZipFile/ZipFileSharedSourceTest.java. There were wrong ArrayIndexOutOfBoundsException like "Index 10 out of bounds for length 10".

The issue disappeared when excluding a method:
make run-test TEST=java/util/zip/ZipFile/ZipFileSharedSourceTest.java JTREG=VM_OPTIONS="-XX:CompileCommand=exclude,java.nio.charset.CharsetDecoder::decode"

Or when disabling the intrinsic (usable as workaround):
-XX:DisableIntrinsic=_countPositives

We noticed that the current implementation requires the "len" argument to be a properly zero (or sign) extended 32 bit integer value. However, this assumption can break due to C2 compiled computations and optimizations.