similar to: [LLVMdev] loop carried dependence analysis?

Hi all, Unfortunately, all my Hunks are failed when I apply : patch -p1 < da.patch command. The problem might be due to the fact that da.patch file was created against revision 167549, but I am on revision 167719 (I believe the most recent one). I am not sure if this cause the problem ? But Preston may I ask you to generate the patch file against revison 167719 ? Thanks in advance. On

Preston, thanks for the explanation and patch. Now it's printing the direction and distance values. On Tue, Nov 13, 2012 at 12:22 PM, Preston Briggs <preston.briggs at gmail.com>wrote: > Erkan, you're right. Sorry about that. > Attached is the most recent version. > > Preston > > > > Hi Preston, >> I am trying to use DA as well. I used your example

On 13.11.2012, at 10:46, erkan diken <erkandiken at gmail.com> wrote: Hi all, Unfortunately, all my Hunks are failed when I apply : patch -p1 < da.patch command. The problem might be due to the fact that da.patch file was created against revision 167549, but I am on revision 167719 (I believe the most recent one). I am not sure if this cause the problem ? But Preston may I ask you to

Hi, The DependenceAnalysis pass will find loop-carried dependences. However, it is a conservative analysis and will sometimes suggest there may be more dependences than actually exist. In your example, I expect the analysis is confused for some reason and is returning the default confused response. You could test it using the isConfused() method. Note that the DVEntry::ALL direction is always

On 11/02/2012 11:02 AM, Hal Finkel wrote: > ----- Original Message ----- >> From: "Tobias Grosser" <tobias at grosser.es> >> To: "preston briggs" <preston.briggs at gmail.com> >> Cc: "Benjamin Kramer" <benny.kra at gmail.com>, "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> >> Sent: Friday, November

The phi instruction is irrelevant; just the way I think about things. The question is if the allocator believes that t0 and t2 interfere. Perhaps the coalescing example was too simple. In the general case, we can't coalesce without a notion of interference. My worry is that looking at interference by ranges of instruction numbers leads to inaccuracies when a range is introduced by a copy.

On Wed, Oct 3, 2012 at 10:15 AM, Matthieu Moy <Matthieu.Moy at grenoble-inp.fr> wrote: > Preston Briggs <preston.briggs at gmail.com> writes: >> Think about costs asymptotically; that's what matters. Calls and >> returns require constant time, just like addition and multiplication. > > Constant time, but not necessarily constant memory. > > Deep recursion

Yes, I quite liked the things I've read about the PBQP allocator. Given what the hardware folks have to go through to get 1% improvements in scalar code, spending 20% (or whatever) compile time (under control of a flag) seems like nothing. And falling back on "average code" is a little disingenuous. People looking for performance don't care about average code; they care about

Here's the current code (abstracted a bit) const Instruction *Src, const Instruction *Dst, // make sure they are loads and stores, then const Value *SrcPtr = getPointerOperand(Src); // hides a little casting, then Src->getPointerOperand const Value *DstPtr = getPointerOperand(Dst); // ditto // see how underlying objects alias, then const GEPOperator *SrcGEP =

> On Sep 10, 2018, at 5:25 PM, Matthias Braun <mbraun at apple.com> wrote: > > > >> On Sep 10, 2018, at 5:11 PM, Preston Briggs <preston.briggs at gmail.com <mailto:preston.briggs at gmail.com>> wrote: >> >> The phi instruction is irrelevant; just the way I think about things. >> The question is if the allocator believes that t0 and t2

Hi, Using Chaitin's approach, removing a copy via coalescing could expose more opportunities for coalescing. So he would iteratively rebuild the interference graph and check for more opportunities. Chaitin was also careful to make sure that the source and destination of a copy didn't interfere unnecessarily (because of the copy alone); that is, his approach to interference was very

My problem was that the constructor for DenseMap has an undocumented constraint. explicit DenseMap(unsigned NumInitBuckets = 0) { init(NumInitBuckets); } if given an explicit argument, requires that the argument be a power of 2. It's checked by an assert in init(), but for some reason my code didn't trip the assertion. Is there a special way I must make to enable asserts? Thanks,

> Only if the recursion is very deep. In practice, a recursive descent > parser isn't going to run out of stack space, nor will a quicksort or > binary-tree walker, The recursive-descent parser case has happened in practice: http://my.opera.com/hallvors/blog/2012/07/17/twitter-crashes-itself-with-commas?1 Also, I've seen some recursion-related PR's in Clang, although I think

On 11/02/2012 10:21 AM, Preston Briggs wrote: > > My initial guess is that a conservative fix is quick and small (make > sure the underlying pointers are loop invariant, otherwise give up). A > better approach would be to somehow turn code like the example into > array references that can be analyzed. I'll need to think about this and > do some reading. Hi Preston, I looked

----- Original Message ----- > From: "Tobias Grosser" <tobias at grosser.es> > To: "preston briggs" <preston.briggs at gmail.com> > Cc: "Benjamin Kramer" <benny.kra at gmail.com>, "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Friday, November 2, 2012 12:56:53 PM > Subject: Re: [LLVMdev]

Hi Alexandru, On 25/01/13 10:23, Alexandru Ionut Diaconescu wrote: > Thank you a lot for your response. I will try to use your approach with chasing > back along def-use chains to find instructions that define the registers used in > the load. Can you tell me please what class/methods/existing path are good for > this? I assume that I must have a method with arguments like the

Howdy, I'm working on writing a dependence analyzer (rather like what LoopDependenceAnalysis wants to be, except a bit more general). While this is a problem of many parts, I'm currently focusing on finding pairs of memory references to test for dependence. Consider this contrived C code: double test2(int n, double *restrict A, double *restrict B, bool flag) { if (flag) { A[0] =

> The underlying liveness datastructure is a list of ranges where each vreg is alive > (ranges in terms of instructions numbered). I remember a couple of later linear scan > papers describing the same thing (Traub et.al. being the first if I remember correctly). > That should be as accurate as you can get in terms of liveness information. It depends on the details. For example, given

On Tue, Feb 5, 2013 at 3:50 PM, Preston Briggs <preston.briggs at gmail.com>wrote: > The MBlaze backend seems to be essentially unmaintained since 2011. The >> maintainer (Wesley Peck who is BCC'ed) seems to have vanished, and in fact >> all emails to him are bouncing. > > >> I propose to remove the MBlaze backend on Friday if none step forward as >> a

Hi Preston, I was wondering ... "Bottom" is a bit overloaded as far as terms go. Would SCEVNaN be a better name for this beast? Sameer. > -----Original Message----- > From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On > Behalf Of Sameer Sahasrabuddhe > Sent: Monday, October 08, 2012 9:16 AM > To: preston.briggs at gmail.com > Cc: LLVM