similar to: [LLVMdev] setAlreadyVectorized does not delete obsolete metadata?

----- Original Message ----- > From: "Renato Golin" <renato.golin at linaro.org> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: "Arnold Schwaighofer" <aschwaighofer at apple.com>, "Arch Robison" <arch.robison at intel.com>, "LLVM Dev" > <llvmdev at cs.uiuc.edu> > Sent: Wednesday, August 20, 2014 2:21:08

Here's an attempt to nail down the annotation semantics with support for respecting forward lexical dependences. Each load, store, call, or invoke instruction can be labeled with !llvm.mem.vector_loop_access, which has two operands: * The first operand is an integer denoting lexical position. The positions need not be consecutive, and may contain duplicates. * The second operand is the

----- Original Message ----- > From: "Arnold Schwaighofer" <aschwaighofer at apple.com> > To: "Johannes Doerfert" <doerfert at cs.uni-saarland.de> > Cc: llvmdev at cs.uiuc.edu, "Arch Robison" <arch.robison at intel.com> > Sent: Wednesday, August 20, 2014 11:29:16 AM > Subject: Re: [LLVMdev] Proposal for

Dear LLVM community, LLVM IR has a concept of 'LoopID' [1] which is a misnomer: (a) LoopIDs are not unique: Any pass that duplicates IR will do it including its metadata (e.g. LoopVersioning) such that thereafter multiple loops are linked with the same LoopID. There is even a test case (Transforms/LoopUnroll/unroll-pragmas-disabled.ll) for multiple loops with the same LoopID. (b)

----- Original Message ----- > From: "Renato Golin" <renato.golin at linaro.org> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: "Arnold Schwaighofer" <aschwaighofer at apple.com>, "Arch Robison" <arch.robison at intel.com>, "LLVM Dev" > <llvmdev at cs.uiuc.edu> > Sent: Wednesday, August 20, 2014 2:16:56

Thanks! That’s probably close enough for practical purposes. I looked at the overrides on various targets, and they all return true if the FMA hardware exists. - Arch From: Jingyue Wu [mailto:jingyue at google.com] Sent: Wednesday, December 10, 2014 2:56 PM To: Robison, Arch Cc: llvmdev at cs.uiuc.edu Subject: Re: [LLVMdev] Best way for JIT to query whether llvm.fma.* is fast? Does

Yes, the modeling of floating-point is trickier. The wrap-around trick used by ConstantRange seems less applicable, and there are the unordered NaNs. Though in all cases, the key abstraction is a lattice of values, so an instance of FPRange should be thought of as a point on a lattice, not an interval. The lattice needs to be complicated enough the cover the cases of interest, but not so

With floating point, won't you need to model a partial order for the end points? I thought there were pairs of floating point values which are incomparable. Not sure if partial order is the right abstraction, but I'm pretty sure a total order isn't. This may make implementing the range comparisons (which are themselves partially ordered) a bit tricky... Philip (Who knows just

Hi, I am trying to use the DependenceAnalysis pass to get the Distance vector for the innermost loop. I am in LLVM learing process. I have used the following code inside my original code to get the distance vector. It is not giving any syntax error but it is has some logical but and giving segmentation fault. void getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesAll();

> Checks against 1.0 are also common. Why not just add a FP range class, like our constant range, and go from there? That's certainly another way to go. My worry is that a more complicated lattice gets us deeper into rounding-mode issues and considerably more work for smaller gain. I like the idea of creating an FPRange class. We could start with a simple one and extend it as experience

More precisely, for a simd loop, if the safelen(VL) clause is specified, there should have no loop-carried lexical backward data dependency within the specified safe vector length VL. We will make this clear in the OpenMP 4.1 spec. Xinmin Tian (Intel) -----Original Message----- From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On Behalf Of Hal Finkel Sent:

I mistakenly not cc’ed the list. On Oct 23, 2013, at 8:28 AM, Renato Golin <renato.golin at linaro.org> wrote: > On 23 October 2013 14:13, Arnold <aschwaighofer at apple.com> wrote: >> What I am proposing for interleaved data vectorization would not transform the loop before vectorization (because there is not much you can do in the general case). There would not be a need

On 02/17/2013 11:15 PM, Hal Finkel wrote: > If the unroller somehow differentiates the metadata coming from different > loop iterations, then BBVectorize can use this information as well. Even > better, we could make BasicAA understand that appropriately marked loads > and stores from different iterations don't alias. Then the AA-based > dependency breaker in the scheduler could

Thanks for the pointers. Looks like LazyValueInfo has the sort of infrastructure I had in mind. LVILatticeVal could be extended to floating point. (The comment "this can be made a lot more rich in the future" is an invitation :-). I'm thinking a simple lattice would address most cases of interest for floating-point checks. The lattice points for floating-point could be all

Yes, I think the 2 outcomes are: - the current spec is unclear and will be clarified - in order to support safelen() and even the simd construct itself, LLVM will require infrastructure work to know when a lexically backwards dependence may have been introduced. Jon -----Original Message----- From: Tian, Xinmin [mailto:xinmin.tian at intel.com] Sent: Monday, September 29, 2014 10:43 AM To:

Oops, meant to send this to the mailing list instead of to Reid privately. (Why cc the mailing list instead of just sending to the mailing list?) In article <CACs=tyJ6zaHeiS0eNhBkdcZE--JY4k7yH9_P1yFbGqod6uymMw at mail.gmail.com>, Reid Kleckner <rnk at google.com> writes: > Looks like a bug. This can probably be simplified with C++11. > > On Fri, Apr 4, 2014 at 10:39

For the Julia language JIT, we'd like be able to tell whether the llvm.fma.* intrinsic has hardware support. What's the best way to query LLVM (JIT) for this information? The information would be used in situations where the user wants to use different algorithms depending on whether FMA hardware is present or not. - Arch D. Robison -------------- next part -------------- An HTML

tools/llvm-objdump/COFFDump.cpp has two loops that advance the loop iterator using "I = ++I" instead of the usual "++I". For example: import_directory_iterator I = Obj->import_directory_begin(); import_directory_iterator E = Obj->import_directory_end(); if (I == E) return; outs() << "The Import Tables:\n"; for (; I != E; I = ++I) {

Hi all, Running LLVM 3.4 to create a custom pass for OpenCL transformations. I am attempting to GEP into a struct using IRBuilder's CreateStructGEP, but I keep getting this assert: aoc: ../../../../../../compiler/llvm/include/llvm/Instructions.h:703: llvm::Type* llvm::checkGEPType(llvm::Type*): Assertion `Ty && "Invalid GetElementPtrInst indices for type!"' failed.

It's a problem in the OpenMP specification. The authors (including some from Intel) intended that the OpenMP simd construct assert no lexically backward dependences exist, but as you say, it's not obvious from the spec. One of our OpenMP community members is going to bring up the ambiguity with the OpenMP committee. - Arch -----Original Message----- From: Humphreys, Jonathan