In article <[email protected]> you wrote:
> In article <[email protected]> you 
> wrote:
> > On Wed, 20 Jul 2016 15:21:58 -0400, Don Poitras wrote:

> > >I have an IPCS exec that broke recently and that
> > >made me look at where I first got the magic numbers to pull registers
> > >out of the linkage stack. I opened an SR with IBM which gave me enough
> > >hints to fix my issue, so it's all rather moot at this point.
> > The format of the linkage stack is well documented in the Principles of 
> > Operation.
> > -- 
> > Tom Marchant

> It is for most of it, but I needed to know what bit represents a BAKR
> call vs. a PC. This is all I could find:

> ---
> Bytes 288-295 contain the entry
> descriptor. EXTRACT STACKED STATE sets the
> condition code to indicate whether the entry-type
> code in the entry descriptor specifies a branch state
> entry or a program-call state entry.
> ---

> I can't very well issue ESTA looking at a dump. For BAKR and non-
> fastpath PC calls that create the linkage stack, the registers are
> stored in the USTA which also I can't find documented anywhere other
> than the aforementioned Share presentation.

Aha! There is some more info doc'd under the ESTA description: 

---
When the entry-type code in the entry descriptor of
the state entry is 0001100 binary, indicating a branch
state entry, the condition code is set to 0. When the
entry-type code is 0001101 binary, indicating a program-
call state entry, the condition code is set to 1.
---

I had already come to the conclusion that I just needed to test
the right-most bit. I had seen dumps with the the high-bit sometimes
on, but this doc says it's not significant. On the other hand,
I believe I've seen some cases where the byte _didn't_ have those
higher-order bits on.

-- 
Don Poitras - SAS Development  -  SAS Institute Inc. - SAS Campus Drive
[email protected]           (919) 531-5637                Cary, NC 27513

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