*---------------------------------------------------------------------*
* *
* Copyright (c) 1995, SAS Institute, Inc. *
* Unpublished - All Rights Reserved *
* *
* S A S / C S A M P L E *
* *
* Name: C2ASMA *
* *
* Language: Assembler *
* *
* EntryPoint: SUMINT *
* *
* EntryType : C2ASMA expects to be called with a C framework *
* in place and standard OS Linkage VL-type parameter *
* list. The parameter list is expected to be of *
* variable length, with at least one(1) argument, *
* all arguments are expected to be pointers to int. *
* The high-order bit of the last argument (a pointer) *
* is expected to be set on. *
* *
* Files Note: 'prefix' is the installation defined high level *
* qualifier for the SAS/C product. *
* *
* Function: Sum the list of integers passed in the parameter list *
* and return the result in R15 to the caller. *
* *
* Purpose: C#AMSA demonstrates assembler communications by using *
* CENTRY, CEXIT, CREGS, along with the CRAB and DSA. *
* It also shows how to process a VL-type parameter list, *
* such as the one produced by SAS/C __asm keyword, and *
* how to return a value to a caller via CEXIT. *
* *
* C2ASMA is designed to be statically linked to a C *
* program and expects to be provided with a normal *
* C framework. *
* *
* Attributes: Re-entrant *
* *
* MVS - See prolog for prefix.SAMPLE.ASM(C2ASMC) *
* *
* CMS - See prolog for SAMPLASM MACLIB(C2ASMC) *
* *
* Misc Notes: *
* - C2ASMA is not assembler dependent, use either *
* Assembler H or High Level Assembler. *
* *
*---------------------------------------------------------------------*
EJECT
PRINT ON,GEN
SUMINT@ CSECT
CREGS USING
SPACE
SUMINT CENTRY INDEP=NO,DSA=0
*---------------------------------------------------------------------*
* Make sure we actually got a plist address on the call. *
*---------------------------------------------------------------------*
SR R3,R3 Clear R3 for sum'ing
LTR R1,R1 Is there a plist?
BZ DONE Nope, just leave w/R3=0!
SPACE
*---------------------------------------------------------------------*
* Sum integers passed via VL-Type parameter list. *
*---------------------------------------------------------------------*
SR R3,R3 Clear R3 for summing
NEXTADD DS 0H
L R4,0(R1) Load pointer
A R3,0(R4) Add integer to sum
TM 0(R1),X'80' End of VL-Plist? <---Note This Check
BNZ DONE Yes, finish up and exit
LA R1,4(R1) No, bump to next argument
B NEXTADD Start again
DONE DS 0H Yes, prepare to return
SPACE
*---------------------------------------------------------------------*
* Exit with the sum of the integers provided to CEXIT in R3. *
*---------------------------------------------------------------------*
CEXIT RC=(R3),INDEP=NO,DSA=0
EJECT
*---------------------------------------------------------------------*
* Constants *
*---------------------------------------------------------------------*
LTORG Area for Literal Pool
*---------------------------------------------------------------------*
* Working Storage *
*---------------------------------------------------------------------*
COPY DSA Required for CENTRY/CEXIT
*---------------------------------------------------------------------*
* Dsects *
*---------------------------------------------------------------------*
COPY CRAB Required for CENTRY/CEXIT
END SUMINT
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