APAR status
Closed as program error.
Error description
Error Message: An unexpected ArrayIndexOutOfBoundsException was thrown for the customer who reported this problem, but the problem is a incorrect calculation which can result in other symptoms depending on how the incorrect value is used. . Stack Trace: N/A . The problem only effects PowerPC (AIX32/64 and LinuxPPC32/64) on Java5, Java6 and Java6.0.1.
Local fix
The problem can be avoided by excluding the compilation of the method that performs the incorrect calculation. If that method is known then the following java command line option can be used to avoid the problem: -Xjit:exclude={Package/Class.method*} Note: Excluding a method can degrade performance depending on how the excluded method is used by the application. In a typical application, excluding one methods has almost no effect on performance.
Problem summary
When a 'left shift' (or power of 2 multiply) is performed along with an 'and' operation we can use the PowerPC 'rlwimn' instruction. This works for most cases, but if the 'and' bit mask as no bits set to 1, the instruction does not work as you might expect resulting an the 'and' operation not being performed as expected.
Problem conclusion
This defect will be fixed in: 6.0.1 SR2 6.0.0 SR10 5.0.0 SR13 7.0.0 SR1 . The JIT was modified to use a different instruction when doing a 'shift' and an 'and' with a mask of 0. . To obtain the fix: Install build 20110921 or later
Temporary fix
Comments
APAR Information
APAR number
IV07698
Reported component name
JIT
Reported component ID
620700124
Reported release
260
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2011-09-16
Closed date
2011-10-04
Last modified date
2012-05-28
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
JIT
Fixed component ID
620700124
Applicable component levels
R260 PSY
UP
R600 PSY
UP
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Document Information
Modified date:
28 May 2012