Problem data saved by first level interrupt handlers

If processing is stopped or an error occurs in one of the first level interrupt handlers (FLIH), you might need to determine the PSW and registers of the interrupted program. Field PSASUPER has bits to indicate if an FLIH was in control:

PSAIO for the IO FLIH
PSASVC for the SVC FLIH
PSAEXT for the external FLIH
PSAPI for the program interrupt FLIH

The following tables show where each FLIH saves the PSW and registers for interrupted tasks or SRB:

Table 1
Table 2
Table 3
Table 4

Table 1. Problem data saved by the SVC FLIH for task and SRB code
Code giving up control	Data saved	Field receiving data	Control block
All SVCs, initially	General purpose registers 7-9	PSAGPREG	PSA
All SVCs, initially	General purpose registers, if a problem occurred	LCCASGPR	LCCA
All SVCs	PSW	RBOPSW	Requestor's RB
	Cross memory status	XSBXMCRS	XSB
	PCLINK stack header	XSBSTKE	XSB
	EAX	XSBEAX	XSB
	Access registers 0-15	STCBARS	STCB
	Current linkage stack entry pointer	STCBLSDP	STCB
Type 1 and 6 SVCs	General purpose registers 0-15	TCBGRS	TCB
Type 2, 3, and 4 SVCs	General purpose registers 0-15	RBGRSAVE	SVRB

Table 2. Problem data saved for a program check for task and SRB code
Code giving up control	Data saved	Field receiving data	Control block
Initially for non-recursive program interruptions	General purpose registers 0-15	LCCAPGR2	LCCA
	PSW	LCCAPPSW	LCCA
	ILC/PINT	LCCAPINT	LCCA
	TEA	LCCAPVAD	LCCA
	TEA AR number	LCCAPTR2	LCCA
	Control registers 0-15	LCCAPCR2	LCCA
	Access registers 0-15	LCCAPAR2	LCCA
Initially for recursive program interruptions	General purpose registers 0-15	LCCAPGR1	LCCA
	PSW	LCCAPPS1	LCCA
	ILC/PINT	LCCAPIC1	LCCA
	TEA	LCCAPTE1	LCCA
	TEA AR number	LCCAPTR2	LCCA
	Control registers 0-15	LCCAPCR1	LCCA
	Access registers 0-15	LCCAPAR1	LCCA
Initially for monitor call interruptions that occur during page fault or segment fault processing	General purpose registers 0-15	LCCAPGR3	LCCA
	PSW	LCCAPPS3	LCCA
	ILC/PINT	LCCAPIC3	LCCA
	TEA	LCCAPTE3	LCCA
	TEA AR number	LCCAPTR3	LCCA
	Control registers 0-15	LCCAPCR3	LCCA
	Access registers 0-15	LCCAPAR3	LCCA
Initially for all trace buffer full interruptions	General purpose registers 0-15	LCCAPGR4	LCCA
For unlocked tasks for page faults or segment faults that require I/O; problem data is moved from the LCCA	Registers		TCB and STCB
	PSW		RB
	Other status		XSB
For locked tasks for page faults or segment faults that require I/O; problem data is moved from the LCCA	Registers		IHSA
	PSW		IHSA
	Other status		XSB for IHSA
For SRBs for page faults or segment faults that require I/O; SRB is suspended, no status is saved

Table 3. Problem data saved by the I/O FLIH for task and SRB code
Code giving up control	Data saved	Field receiving data	Control block
Initially	General purpose registers 0-15	SCFSIGR1	SCFS
	Control registers 0-15	SCFSICR1	SCFS
	Access registers 0-15	SCFSIAR1	SCFS
For unlocked tasks	General purpose registers 0-15	TCBGRS	TCB
	PSW	RBOPSW	RB
	Cross memory status	XSBXMCRS	XSB
	EAX	XSBEAX	XSB
	Access registers 0-15	STCBARS	STCB
	Current linkage stack entry pointer	STCBLSDP	STCB
For locally locked tasks	General purpose registers 0-15	IHSAGPRS	IHSA for locked address space
	PSW	IHSACPSW	IHSA for locked address space
	Access registers 0-15	IHSAARS	IHSA for locked address space
	Current linkage stack entry pointer	IHSALSDP	IHSA for locked address space
	Cross memory status	XSBXMCRS	XSB for locked address space
	EAX	XSBEAX	XSB for locked address space
For SRBs and non-preemptive TCBs	General purpose registers 0-15	SCFSIGR1	SCF
For SRBs and non-preemptive TCBs	PSW	FLCIOPSW	PSA

Table 4. Problem data saved by the external FLIH for task and SRB code
Code giving up control	Data saved	Field receiving data	Control block
Initially	General purpose registers 7-10	PSASLSA	PSA
For locally locked tasks	General purpose registers 0-15	IHSAGPRS	IHSA
	PSW	IHSACPSW	IHSA
	Access registers 0-15	IHSAARS	IHSA
	Current linkage stack entry pointer	IHSALSDP	IHSA
	Cross memory status	XSBXMCRS	XSB
	EAX	XSBEAX	XSB
Unlocked tasks	General purpose registers 0-15	TCBGRS	TCB
	PSW	RBOPSW	RB
	Access registers 0-15	STCBARS	STCB
	Current linkage stack entry pointer	STCBLSDP	STCB
	Cross memory status	XSBXMCRS	XSB
	EAX	XSBEAX	XSB
For SRBs and non-preemptive TCBs	General purpose registers 0-15	SCFSXGR1	SCFS
	PSW	SCFSXPS1	SCFS
	Control registers 0-15	SCFSXCR1	SCFS
	Access registers 0-15	SCFSXAR1	SCFS
If first recursion	General purpose registers 0-15	SCFSXGR1	SCFS
	PSW	SCFSXPS2	SCFS
	Control registers 0-15	SCFSXCR2	SCFS
	Access registers 0-15	SCFSXAR2	SCFS
If second recursion	General purpose registers 0-15	SCFSXGR3	SCFS
	PSW	FLCEOPSW	PSA
	Control registers 0-15	SCFSXCR3	SCFS
	Access registers 0-15	SCFSXAR3	SCFS