Re: [COFF] [TUHS] Unix quix

FWIW: System 360 uses what was called the 'push down save area' as part of the function calling convention. Each routine declared and creates local storage for the registers. Being reentrant was certainly possible and many languages such as the Algol and APL families were. It's funny since S/360 was the first architecture I knew deeply (*i.e.* got paid to program), and working on support for York/APL at the time (and began learning the Univac 1100 too), I just thought this was natural until I began to learn about other processors ISA's like the PDP-11 family that had an SP. I remember, thinking -- this is so cool. But as you said, originally early Fortran and Cobol didn't require same. The typical calling conventions was something like this was pretty standard for the S/360: WORKAREA DSECT , Reentrant work area (stack like function) DS 18F Save area FIELD1 DS F Some variable FIELD2 DS F Another variable WORKLEN EQU *-WORKAREA Length of reentrant work area SUBRTN1 RSECT , HLASM will perform reentrant checking STM R14,R12,12(R13) Save registers at entry LR R12,R15 Set code base register USING SUBRTN1,R12 Establish code addressability LGHI R0,WORKLEN Get length of reentrant work area STORAGE OBTAIN, Obtain reentrant work area X LENGTH=(0) ..Length is in R0 ST R1,8(,R13) Forward chain in prev save area ST R13,4(,R1) Backward chain in next save area L R14,20(,R13) Get R1 at entry (parameters) LR R13,R1 Set up new save area/reentrant workarea USING WORKAREA,R13 Establish work area addressability LM R2,R3,0(R14) Get addresses of parameters STM R2,R3,FIELD1 Save parameter addresses for later … *** Subroutine Logic goes here … LR R1,R13 Address to be released L R13,4(,R13) Address of prior save area LGHI R0,WORKLEN Length of storage to release STORAGE RELEASE, Release reentrant work area X ADDRESS=(1), ..Address in R1 X LENGTH=(0) ..Length in R0 LM R14,R12,12(R13) Restore registers OI 15(R13),X'01' This bit on means this save area is inactive BR R14 Return to caller On Thu, Jan 23, 2020 at 12:47 AM Peter Jeremy <peter(a)rulingia.com> wrote: