llvm dev - Oct 2008 - [LLVMdev] Default implementations for __ashldi3, __ashrdi3, __divdi3, __udivdi3, etc?

Are there existing "generic" implementations for these functions under
the same license as LLVM? By generic I mean C or IR that doesn't use  
any particular HW intrinsics.

I read up on divides in Knuth's Seminumerical book, but decided to use  
base-2 long division on the first go-around for simplicity. I know  
it's not very efficient and I'm looking for shortcuts to something  
better.

Pointers to divide algo's could also be of use.

Thanks,

Dan

Dan, 
 For the shifts, check out chapter 2 of hacker's delight by Guy Steele.

http://www.hackersdelight.org/

-----Original Message-----
From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu]
On Behalf Of Daniel M Gessel
Sent: Friday, October 31, 2008 10:13 AM
To: LLVM Developers Mailing List
Subject: [LLVMdev] Default implementations for __ashldi3, __ashrdi3,
__divdi3,__udivdi3, etc?

Are there existing "generic" implementations for these functions under
the same license as LLVM? By generic I mean C or IR that doesn't use  
any particular HW intrinsics.

I read up on divides in Knuth's Seminumerical book, but decided to use  
base-2 long division on the first go-around for simplicity. I know  
it's not very efficient and I'm looking for shortcuts to something  
better.

Pointers to divide algo's could also be of use.

Thanks,

Dan

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On Oct 31, 2008, at 10:13 AM, Daniel M Gessel wrote:
> Are there existing "generic" implementations for these functions
under
> the same license as LLVM? By generic I mean C or IR that doesn't use
> any particular HW intrinsics.
Hi Daniel,

We're working on a complete ground-up implementation of the API vended  
by libgcc, including these routines, under the LLVM license.  We need  
to finish it and get approval to release them as part of llvm.org, but  
I expect it to happen in the next month or two.  I don't know if this  
will align with your needs or not, but I thought I would mention it.

-Chris

That's great; it will really fill out 64 bit integer support on 32 bit  
machines.

Thanks,

Dan

On Oct 31, 2008, at 4:07 PM, Chris Lattner wrote:
>
> On Oct 31, 2008, at 10:13 AM, Daniel M Gessel wrote:
>
>> Are there existing "generic" implementations for these
functions
>> under
>> the same license as LLVM? By generic I mean C or IR that doesn't
use
>> any particular HW intrinsics.
>
> Hi Daniel,
>
> We're working on a complete ground-up implementation of the API vended
> by libgcc, including these routines, under the LLVM license.  We need
> to finish it and get approval to release them as part of llvm.org, but
> I expect it to happen in the next month or two.  I don't know if this
> will align with your needs or not, but I thought I would mention it.
>
> -Chris
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev