Free space in program .

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

Hi ,

Is it possibel to determine the free space in the ASM program by looking at listing . I want to know know how much space is still left with the base registers .

Thanks

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enrico-sorichetti · Posted: Fri Aug 14, 2009 6:13 pm

reading a listing will let You discover anything You want to know about an assembler program

Bill O'Boyle · Posted: Fri Aug 14, 2009 6:15 pm

Are you referring to CSECT Base-Registers? What does your CSECT USING statement specify?

What is the LENGTH of the program after Assembly?

Is this CICS/Assembler or Batch?

Actually, the question should refer to register "addressability" and not "space".

Bill

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

I am using this calculation for free space :

(Number of base register * 4096 - 1) - ( current location counter - start of pgm LC)

But this is taking some time to find all the parametrs . The PGm is batch.
Is it possible ..does soemthing in listing can tell me directly without going thru the above cal.

enrico-sorichetti · Posted: Fri Aug 14, 2009 6:38 pm

any suggestion might be wrong unless You tell the base register allocation/use strategy

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

For example , I am declaring the base registers as :

PGM START 0
LM R3,R5,ADD
USING PGM,R3,R4,R5

.......
ADD DC A(PGM),A(PGM+4095),A(PGM+8191)

But this code being know to me , is easy to figure out the free space . My task gets time consuming when i analyze some complex modules having multiple csect . Is there any trick some listing data ..which can solve the purpose without doing manual calculation .

dick scherrer · Posted: Fri Aug 14, 2009 8:35 pm

Hello,

I must be having a brain-slow Friday. . .

I'm confused on exactly what the goal is.

Does each new csect not "start over" using a new set of registers?

How will the "answer" be used?

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

doing this whole thing on the real code(listing) is taking some time to figure out ,going in each csect and finding the number of registers used in base addressing , task becomes bit more time consuming when the program is having a number of USING declarative to establish desct addresiblity also , if the base addres registers is declared at two diff location in the same csect , it again consumes time to find the Total number of base registers used in csect .
Is this the only way to do this .can something be done to estimate this without going thu the trouble of this much analysis , is any tool available ?

Thanks

dick scherrer · Posted: Fri Aug 14, 2009 10:10 pm

Hello,

Yes, this will surely take an inordinate amount of time. . .

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

I am developing a tool for debugging pgm in my application , wherien It will implant WTO macros in pgm to trace the trajectory of a record in pgm . I have to calculate the free space in pgm to decide how many WTO my tool can implant in the pgm .

MBabu · Posted: Sat Aug 15, 2009 6:08 am

can you put a DC AL4(*-csectname) at the end and see what it gets as a value in the listing?

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

Babu ,

I don't have system with me now so cant experiment with this code , But i believe DC AL4(*-csectname) wont solve the problem , as it will just give the length/size of CSECT.For free space anyhow the base registers should be identified .

Robert Sample · Posted: Sat Aug 15, 2009 6:23 pm

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

Please could you cross check this statement again , I guess may be some confusion is here or may be you are saying this in context to some specific situation .

Robert Sample · Posted: Sat Aug 15, 2009 7:26 pm

And you're not able to figure out how to generalize the formula?

You might want to rethink your approach and come up with a solution that you can understand and implement -- or if you cannot, perhaps you're not ready to develop such a tool yet.

enrico-sorichetti · Posted: Sat Aug 15, 2009 8:11 pm

Robert Sample · Posted: Sat Aug 15, 2009 8:22 pm

With the advent of baseless assembler programming, it'll be interesting to see how you handle this the first time you come across it. Without a base register, how are you going to proceed?

MBabu · Posted: Sat Aug 15, 2009 9:06 pm

enrico-sorichetti · Posted: Sat Aug 15, 2009 9:20 pm

the statement as stated is just plain wrong
csect size and number of base registers are UNRELATED
all depends on the techniques being used

for a beginner it might be easier to use as many registers as needed ( csect_size / 4096 )
for a more experienced programmer not true

MBabu · Posted: Sun Aug 16, 2009 11:28 am

because the original question was related to addressability, I took "CSECT size" to mean "addressability within a CSECT", but strictly speaking, Enrico, you are correct that the way it is written states that the total length of the csect, not addresability within it, depends on the number of base registers and that statement, as written, is definitely wrong. I read too much into it.

It is not uncommon to have data areas at the end of a nonreentrant CSECT that are not addressable by the base registers which access the code but are addressed by index registers or temporary 'base' registers (pointers). An even more common case is a data only CSECT which has no base registers at all because it has no code.

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

I guess discussion is moving in to CSECT size , and what i said is in context to my problem , wherein I need to find the frees space spared by the base registers.

CSECT size - Area(bytes) my base registers are capable to address. It can go way beyond 4096 if I use more than 1 BR.

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

I am trying to read the listing of a compiled program in order to find an alternative of knowing the base registers . The program is having one CSECT only . In the following USING map , Registers 3,4,9,12 are for DSECT addressability and Registers 10 and 11 are the base registers declared for the CSECT .

So this CSECT is capable of addr 8192 bytes . Please correct me as I am just guessing and dont know how to decipher the USING map.

MBabu · Posted: Tue Aug 18, 2009 9:41 am

This has been explained already, but a CSECT is just a block of memory that contains code and data. It does not address anything and the number of base registers used in the program has nothing to do with the total size of a CSECT. If you want the size of a CSECT, the USING MAP will not give you anything useful. I think you need to get the terminology correct because now it seems no one can figure out what you are asking.

Pankaj Shrivastava · New User Joined: 24 Jul 2009 Posts: 51 Location: Pune

sorry i asked this question , but still cant understand what was so confusing in the question , Did no body ever find such a situation where a need to find the free space arose . I agree that there are special techniques as pointed by Enrico to address without base registers , But i have been asking right from the begining that my requirement is,given a set of base registers to establish the addresibilty ..is there any convinient way to find the free space .
Anyways thanks all for giving time in the discussion...this surely has given some valauble info

..but not a perfect solution

enrico-sorichetti · Posted: Tue Aug 18, 2009 2:12 pm