IJ36428: FLOATING POINT EXCEPTION DURING JIT COMPILATION.

APAR status

• Closed as program error.

Error description

• Error Message: SIGFPE causes a CICS A147 Abend
  .
  Stack Trace: In Java 7.1
  {libj9jit27.so}{TR_MultipleCallTargetInliner::exceedsSizeThresho
  ld(int,TR_Block*,TR_ByteCodeInfo&,int,TR_ResolvedMethod*,TR_Reso
  lvedMethod*,TR_Node*,bool)}
  {libj9jit27.so}{TR_InlinerBase::findInlineTargets(TR_CallStack*,
  TR_CallSite*)}
  {libj9jit27.so}{TR_EstimateCodeSize::isInlineable(TR_CallStack*,
  TR_CallSite*)}
  {libj9jit27.so}{TR_EstimateCodeSize::estimateCodeSize(TR_CallTar
  get*,TR_CallStack*,bool)}
  {libj9jit27.so}{TR_EstimateCodeSize::calculateCodeSize(TR_CallTa
  rget*,TR_CallStack*,bool)}
  {libj9jit27.so}{TR_InlinerBase::findInlineTargets(TR_CallStack*,
  TR_CallSite*)}
  ...
  In Java 8+ the crashing function would be
  scaleSizeBasedOnBlockFrequency()
  .
  Typically this exception would not result in a FPE being raised,
  but it can still happen when using a custom executable that uses
  JNI to launch the JVM and that executable is setup to raise FPE
  signals rather then ignore the condition. Therefore this issue
  is not possible when using the standard java executable.
  

Local fix

• The issue can be avoiding by disabling inlining for the method
  where the issue is encountered:
  -Xjit:{<package>/<class>.<method>*}(disableInlining)
  or disable inlining globally, which will have a substantial
  performance impact:
  -Xjit:disableInlining
  

Problem summary

• The JIT casts the result of an float calculation into a 32bit
  integer, but the original float might overflow the 32bit integer
  resulting in a FPE if the executable is configured to do so.
  

Problem conclusion

• The JIT was modified so that the target of the float->integer
  cast will be set to MAX_INT when the float is larger then
  MAX_INT.
  .
  This APAR will be fixed in the following Java Releases:
   7 R1 SR5 FP5 (7.1.5.5)
   8 SR7 FP5 (8.0.7.5)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  Service Refreshes and Fix Packs can be found at:
   https://www.ibm.com/developerworks/java/jdk/
  

Temporary fix

Comments

APAR Information

• 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