Bug 1148 - support byte reverse instructions in PowerISA v3.1B in binutils
Summary: support byte reverse instructions in PowerISA v3.1B in binutils
Status: RESOLVED INVALID
Alias: None
Product: Libre-SOC's first SoC
Classification: Unclassified
Component: Source Code (show other bugs)
Version: unspecified
Hardware: PC Windows
: --- enhancement
Assignee: Dmitry Selyutin
URL:
Depends on:
Blocks:
 
Reported: 2023-08-30 16:08 BST by Dmitry Selyutin
Modified: 2023-08-30 17:18 BST (History)
3 users (show)

See Also:
NLnet milestone: ---
total budget (EUR) for completion of task and all subtasks: 0
budget (EUR) for this task, excluding subtasks' budget: 0
parent task for budget allocation:
child tasks for budget allocation:
The table of payments (in EUR) for this task; TOML format:

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Description Dmitry Selyutin 2023-08-30 16:08:46 BST 
All instructions listed in #1119 need binutils support.
Comment 1 Dmitry Selyutin 2023-08-30 16:10:15 BST 
These instructions, like instructions from #1147, are present in vanilla binutils, but lack corresponding SVP64 code.
Comment 2 Jacob Lifshay 2023-08-30 16:13:43 BST 
(In reply to Dmitry Selyutin from comment #0)
> All instructions listed in #1119 need binutils support.

iirc #1119 has the budget for these, since lkcl was expecting you to just do them as part of #1119 and I assigned budget based on that. so, do you want to move that budget here or close this and just use #1119?
Comment 3 Jacob Lifshay 2023-08-30 16:17:46 BST 
(In reply to Jacob Lifshay from comment #2)
> (In reply to Dmitry Selyutin from comment #0)
> > All instructions listed in #1119 need binutils support.
> 
> iirc #1119 has the budget for these, since lkcl was expecting you to just do
> them as part of #1119 and I assigned budget based on that. so, do you want
> to move that budget here or close this and just use #1119?

or we could close this and add the budget to bug #1047 so they're all in one place?
Comment 4 Dmitry Selyutin 2023-08-30 16:20:09 BST 
(In reply to Jacob Lifshay from comment #3)
> or we could close this and add the budget to bug #1047 so they're all in one
> place?

I assume you mean #1147, right? Well, it were you to add "except byte reverses". :-)
Comment 5 Jacob Lifshay 2023-08-30 16:24:31 BST 
(In reply to Dmitry Selyutin from comment #4)
> (In reply to Jacob Lifshay from comment #3)
> > or we could close this and add the budget to bug #1047 so they're all in one
> > place?
> 
> I assume you mean #1147, right?

yes, oops.

> Well, it were you to add "except byte
> reverses". :-)

i can always undo that...I just did it since I thought the plan was to do byte reverses as part of #1119
Comment 6 Jacob Lifshay 2023-08-30 16:49:31 BST 
(In reply to Jacob Lifshay from comment #5)
> i can always undo that...I just did it since I thought the plan was to do
> byte reverses as part of #1119

lkcl requested merging into #1147 unless you think the task is big enough that you'd need more money before fully completing it:
https://libre-soc.org/irclog/%23libre-soc.2023-08-30.log.html#t2023-08-30T16:43:44
ghostmansd, what do you think?
Comment 7 Dmitry Selyutin 2023-08-30 17:02:37 BST 
(In reply to Jacob Lifshay from comment #6)
> (In reply to Jacob Lifshay from comment #5)
> > i can always undo that...I just did it since I thought the plan was to do
> > byte reverses as part of #1119
> 
> lkcl requested merging into #1147 unless you think the task is big enough
> that you'd need more money before fully completing it:
> https://libre-soc.org/irclog/%23libre-soc.2023-08-30.log.html#t2023-08-30T16:
> 43:44
> ghostmansd, what do you think?


I'm totally fine with having one big task. Some rationale on why things ended up this way: we had two tasks for supporting these instructions in ISACaller, I just made two symmetrical tasks for binutils.

As for the payment, I'm not sure what sum to put. Based on my experience with 1068 and similar tasks, there might be issues on openpower-isa side (be it codegen, new operands or states, etc.). Even 700 EUR for 1147 was an arbitrary choice based on the fact that 1119 (which gave birth to 1148) had 300 EUR...