similar to: [LLVMdev] setOnlyReadsMemory / setDoesNotAccessMemory

Nyx wrote: > Hello, > > I'm in a situation where my code is calling many native functions. > Sometimes, these calls are simply calls to static "accessor" methods that > read a variable in some class object (object pointer as input, member > variable value returned as output). I was wondering if using the > setOnlyReadsMemory method on the native function objects

But, which optimization pass will take advantage of those flags? As for nounwind, that means "can't throw an exception"? - Maxime John McCall-2 wrote: > > Nyx wrote: >> Hello, >> >> I'm in a situation where my code is calling many native functions. >> Sometimes, these calls are simply calls to static "accessor" methods that >>

----- Original Message ----- > From: "James Molloy via llvm-dev" <llvm-dev at lists.llvm.org> > To: "Vaivaswatha Nagaraj" <vn at compilertree.com> > Cc: "LLVM Dev" <llvm-dev at lists.llvm.org> > Sent: Thursday, December 3, 2015 4:41:46 AM > Subject: Re: [llvm-dev] Function attributes for LibFunc and its impact on GlobalsAA > >

Hi Mehdi, The ISO C specification does permit the math functions to modify ‘errno’, but I thought that the ‘-fno-math-errno’ option was to tell the optimiser to assume that ‘errno’ is not modified by the math functions. Explicitly providing ‘-fno-math-errno’ is not restoring the elision optimisation that was performed by LLVM v3.8, and this is really only a driver option, with ‘-fmath-errno’

A little while ago I asked a question on CFE-Dev about a change in the behaviour of programs using the ISO C math functions, although that question should have been put to LLVM-Dev. But I got excellent clarification of the problem anyway. However, since then I have been trying to adapt our out-of-tree implementation to get the previous behaviour. The problem is that something like: #include

Aiming at a release later in October (before Xen Summit I would hope), I''d like to cut RC1 next week. Please indicate any bug fixes that so far may have been missed in the backports already done. Jan

Hello, I''m scheduled to give a rspec brown bag this Wednesday (11/22) for my company (Pivotal Computer Systems, http://www.pivotalsf.com). I did see Dave Astel''s talk as well as several of my coworkers. The developers at my workplace are experienced Agile developers. What would be some good things to focus on for this brown bag? Are there slides to presentations that would be

I have a two part question Part 1) I am trying to remove characters in a string based on the position of a key character in another string.? I have a solution that works but it requires a for-loop.? A vectorized way of doing this has alluded me.? CleanRead<-function(x,y) { ? if (!is.character(x)) ??? x <- as.character(x) ? if (!is.character(y)) ??? y <- as.character(y) ?

On 5/25/2017 3:43 PM, Robert Moskowitz wrote: > > Note that you do not have xfce-utils or leafpad. > > Do you have themes? What is your background. > > I have actually gotten Xfce working. Kindof. I am into Xfce via > vncserver. It pretty much looks like Xfce on my Fedora systems. > Backleveled a bit of course. No sensor applet to show the cpu temp > for example.

On 24/02/13 09:02, Duncan Sands wrote: > in order to do this, the optimizers need to know that the call to > @trace_integer does not modify the contents of @pt. Is it logically > possible for them to deduce this? If not, no optimizer can do what > you want. Yeah, I thought about that and then realized in this context they could not (it's an external function). Is there some

On 23 May 2014 09:42, Robert Lougher <rob.lougher at gmail.com> wrote: > Hi Nick, > > Thanks for replying. Bug filed: > http://llvm.org/bugs/show_bug.cgi?id=19842 Thank you! Strangely enough, my first conclusion was that %p was being marked > readnone incorrectly as it wasn't handling the copy via @get_addr. > Sorry -- saying %p alone is ambiguous because

Confirmed, this is a bug. This define i32* @get_pntr(i32* %p) nounwind uwtable { entry: ret i32* %p } define void @store(i32* %p) noinline nounwind uwtable { entry: %call = call i32* @get_pntr(i32* %p) store i32 10, i32* %call, align 4 ret void } run through opt -functionattrs gets a 'readnone' on @store's %p. That's wrong, it clearly stores to it. The bug is due to

Hi, I'm investigating a bug which I have so far been able to narrow down to the following small testcase: ======== test.c =========== int *get_pntr(int *p) { return p; } __attribute__((noinline)) void store(int *p) { int *p2 = get_pntr(p); *p2 = 10; } int test() { int i; store(&i); return i; } ----------------------------- If this is compiled in two steps as

On 05/21/2014 02:52 PM, Robert Lougher wrote: > On 21 May 2014 21:40, Robert Lougher <rob.lougher at gmail.com> wrote: >> define i32* @get_pntr(i32* readnone %p) { >> entry: >> ret i32* %p >> } >> >> define void @store(i32* nocapture readnone %p) { >> entry: >> store i32 10, i32* %p, align 4, !tbaa !1 >> ret void >> }

On 01/05/2017 03:10 PM, Reid Kleckner wrote: > On Thu, Jan 5, 2017 at 10:39 AM, Hal Finkel <hfinkel at anl.gov > <mailto:hfinkel at anl.gov>> wrote: > > I don't understand why that's desirable, and I think it would > severely limit our ability to infer these attributes for functions > that unwind. You'd need to prove things -- likely

LLVM today does not clearly specify if a function specified to not write to memory (i.e. readonly or readnone) is allowed to throw exceptions. LangRef is ambiguous on this issue. The normative statement is "[readnone/readonly functions] cannot unwind exceptions by calling the C++ exception throwing methods" which does not decide an answer for non C++ languages. It used to say (h/t

On 01/05/2017 12:17 PM, Reid Kleckner wrote: > On Thu, Jan 5, 2017 at 9:19 AM, Hal Finkel via llvm-dev > <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: > > > On 01/05/2017 10:55 AM, Sanjoy Das wrote: > > Hi Hal, > > On Thu, Jan 5, 2017 at 6:12 AM, Hal Finkel <hfinkel at anl.gov > <mailto:hfinkel

On 01/05/2017 10:55 AM, Sanjoy Das wrote: > Hi Hal, > > On Thu, Jan 5, 2017 at 6:12 AM, Hal Finkel <hfinkel at anl.gov> wrote: >> On 01/04/2017 10:35 PM, Sanjoy Das via llvm-dev wrote: >>> I just realized that there's an annoying corner case to this scheme -- >>> I can't DSE stores across readnone maythrow function calls because the >>>

Dear All, Are functions marked as readnone or readonly in the LLVM IR allowed to generate output or to exhibit exceptional behavior (e.g., calling abort(), generating an MMU fault, etc.)? The SAFECode compiler has a set of run-time checks that pass or fail based solely on the input arguments and, in some cases, global state. They do not modify a program's global state, but they do print

Hi, The last time the AVX backend was mentioned on this list seems to be from November 2010, so I would like to ask about the current status. Is anybody (e.g. at Cray?) still actively working on it? I have tried both LLVM 2.9 final and the latest trunk, and it seems like some trivial stuff is already working and produces nice code for code using <8 x float>. Unfortunately, the backend