I am attempting to upgrade some existing subroutines to 31-bit
addressing, so that programs which call them aren't restricted to 24-bit
addressing.

I thought I understood the requirements, but after compiling the COBOL
programs and assembling the ALC, I _sometimes_ get addressing
exceptions.  Naturally, it's never when I test, but only after I install
in production!

The following Assembler subroutine, used to enqueue a data set that is
shared among many users while a record is written to it, is one that has
caused problems.  A caller running AMODE 31, RMODE ANY, and loaded above
the 16M line statically calls the "Enqueue Manager", and the code
fails.  When I look at the PSW, bit 32 is ON, so that word 2 of the PSW
is X'8xxxxxxx'.  The address in Register 15 is that of ZENQMGR, and the
instruction that fails is the branch around the 'module id' assembled
into the program by the SAVE macro.

Does someone know what I'm forgetting to do correctly?

Here is a portion of the Assembler listing:
(I hope you can read it; my browser let me put it in with a fixed font
from a 3270 Mod 5 emulator.)

ZENQMGR  MVS/ESA: GENERAL ENQUEUE/DEQUEUE MANAGEMENT
ROUTINE                                                   Page    3
  Active Usings: None
  Loc  Object Code    Addr1 Addr2  Stmt   Source
Statement                                  HLASM R2.0  1999/02/01 09.21
                                      2 *AUTHOR. COLIN
CAMPBELL                                                 00020000
                                      3 *        PRINT
NOGEN                                                    00030001
000000                                4 ZENQMGR
CSECT                                                          00040000
                                      5 ZENQMGR  AMODE
31                                                       00050000
                                      6 ZENQMGR  RMODE
ANY                                                      00060000
                                      7 ENQ      CSAVE
R12,RETCODE                                              00070000

8+***********************************************************************

                                      9+* CSAVE MACRO - COMPLETE
TRANSFER AND RETURN OF CONTROL LOGIC         *
                                     10+*     OPTIONS - CREATE SYMBOLIC
REGISTERS, SET BASE REGISTER,         *
                                     11+*               PLACE RETURN
CODE IN REG 15 FROM A HALF- OR FULLWORD, *
                                     12+*               AND GENERATE OR
SUPPRESS A NEW SAVE AREA.             *
                                     13+*        NOTE - ALWAYS USE IN
CONJUNCTION WITH 'EXIT' MACRO.          *

14+***********************************************************************

                            00000    15+R0       EQU
0                                                        02-REGS
                            00001    16+R1       EQU
1                                                        02-REGS
                            00002    17+R2       EQU
2                                                        02-REGS
                            00003    18+R3       EQU
3                                                        02-REGS
                            00004    19+R4       EQU
4                                                        02-REGS
                            00005    20+R5       EQU
5                                                        02-REGS
                            00006    21+R6       EQU
6                                                        02-REGS
                            00007    22+R7       EQU
7                                                        02-REGS
                            00008    23+R8       EQU
8                                                        02-REGS
                            00009    24+R9       EQU
9                                                        02-REGS
                            0000A    25+R10      EQU
10                                                       02-REGS
                            0000B    26+R11      EQU
11                                                       02-REGS
                            0000C    27+R12      EQU
12                                                       02-REGS
                            0000D    28+R13      EQU
13                                                       02-REGS
                            0000E    29+R14      EQU
14                                                       02-REGS
                            0000F    30+R15      EQU
15                                                       02-REGS
000000 47F0 F00C            0000C    31+ENQ      B
12(0,15)                          BRANCH AROUND ID       02-SAVE
000004 07                            32+         DC
AL1(7)                            LENGTH OF IDENTIFIER   02-SAVE
000005 E9C5D5D8D4C7D9                33+         DC
CL7'ZENQMGR'                      IDENTIFIER             02-SAVE
00000C 90EC D00C            0000C    34+         STM
14,12,12(13)                      SAVE REGISTERS         02-SAVE
000010 18CF                          35+         LR    R12,15     SET
BASE REGISTER                             01-CSAVE
                 R:C  00000          36+         USING
ZENQMGR,R12                                              01-CSAVE
000012 47F0 C074            00074    37+         B
B0001                                                    01-CSAVE
000016 58D0 C030            00030    38+         L
13,A0001+4                                               01-CSAVE
00001A 48F0 C194            00194    39+         LH
15,RETCODE                                              X01-CSAVE
                                       +                         SET
RETURN CODE
00001E 58E0 D00C            0000C    40+         L

000022 980C D014            00014    41+         LM
0,12,20(13)                       RESTORE THE REGISTERS  02-RETUR
000026 9601 D00F      0000F          42+         OI
15(13),X'01'                      SET RETURN INDICATION  02-RETUR
00002A 07FE                          43+         BR
14                                RETURN                 02-RETUR
00002C 0000000000000000              44+A0001    DC    18F'0' DEFINE
SAVE AREA                                  01-CSAVE
000074 50D0 C030            00030    45+B0001    ST
13,A0001+4                                               01-CSAVE
000078 18ED                          46+         LR
14,13                                                    01-CSAVE
00007A 41D0 C02C            0002C    47+         LA    13,A0001    CHAIN
SAVE AREAS                             01-CSAVE
00007E 50DE 0008            00008    48+         ST
13,8(14)                                                 01-CSAVE
000082 1BFF                          49          SR
R15,R15                                                  00080000
000084 40F0 C194            00194    50          STH
R15,RETCODE                                              00090000

CSAVE and its companion macros EP (Entry Point) and EXIT are in-house
developed code.  (CSAVE can be told to generate reentrant code, and to
skip generation of a Save Area entirely.)  As you can see, CSAVE uses
IBM standard SAVE & RETURN macros.

Your ideas are appreciated.
Colin Campbell

Do you really mean "addressing exception" as in S0C5 or program
interrupt 0005? These are very rare except in programs that mess with
real addresses.

Perhaps you could show us the symptom dump and the last few entries in
the trace table if you have this.

Andy Wood

[Posted and mailed]

:>I am attempting to upgrade some existing subroutines to 31-bit
:>addressing, so that programs which call them aren't restricted to 24-bit
:>addressing.

:>I thought I understood the requirements, but after compiling the COBOL
:>programs and assembling the ALC, I _sometimes_ get addressing
:>exceptions.  Naturally, it's never when I test, but only after I install
:>in production!

:>The following Assembler subroutine, used to enqueue a data set that is
:>shared among many users while a record is written to it, is one that has
:>caused problems.  A caller running AMODE 31, RMODE ANY, and loaded above
:>the 16M line statically calls the "Enqueue Manager", and the code
:>fails.  When I look at the PSW, bit 32 is ON, so that word 2 of the PSW
:>is X'8xxxxxxx'.  The address in Register 15 is that of ZENQMGR, and the
:>instruction that fails is the branch around the 'module id' assembled
:>into the program by the SAVE macro.

:>Does someone know what I'm forgetting to do correctly?

What are the PSW contents?

What is the xxxxxxx compared to the value of R15?

What is the exact PIC?

If 10 or 11, what is the address that failed translation?

If 4, is the program linked as reentrant?

   [ listing snipped ]

--

Director, Dissen Software, Bar & Grill - Israel

I looked at the code very carefully, and saw nothing wrong.  It could be
a loop back to +0.

If the program is doing an ENQ, look at the ENQ parm list very, very carefully.

I have not seen an S0C5 (the classic addressing exception) since the advent
of virtual storage; the _only_ way to get one is if the page tables are
seriously screwed up.  If they are in that bad a shape, the system may well
nose dive before the S0C5 is reported!

We need more information!

[snip]

-- Steve Myers

The E-mail addresses in this message are private property.  Any use of them
to  send  unsolicited  E-mail  messages  of  a  commerical  nature  will be
considered trespassing,  and the originator of the message will be  sued in
small claims court in Camden County,  New Jersey,  for the  maximum penalty
allowed by law.