Using CEE3SPM and XUFLOW to enable and disable hardware conditions

You can change the enablement of certain hardware interrupts using the CEE3SPM callable service and XUFLOW runtime option under Language Environment (see z/OS Language Environment Programming Reference for syntax).

Language Environment provides the CEE3SPM callable service to replace assembler language routines that manipulate bits 20 through 23 of the Program Status Word (PSW) to enable or disable the following hardware interrupts:
  • Decimal overflow
  • Exponent underflow
  • Fixed-point overflow
  • Significance

The XUFLOW runtime option specifies whether an exponent underflow exception causes a program interrupt. Both CEE3SPM and XUFLOW can change the condition handling semantics of the HLL or HLLs of your application. Therefore, use CEE3SPM and XUFLOW only if you understand the effect they have on your application.

Parent topic: Enablement step