search for: memoryused

Hi, I am new to MemorySSA and wanted to understand its capabilities. Hence I wrote the following program (test.c): int N; void test(int *restrict a, int *restrict b, int *restrict c, int *restrict d, int *restrict e) { int i; for (i = 0; i < N; i = i + 5) { a[i] = b[i] + c[i]; } for (i = 0; i < N - 5; i = i + 5) { e[i] = a[i] * d[i]; } } I compiled this program using

In particular, if you want to add support, the right way to know what to rename is (off the top of my head) add a flag or something to have renamepass reset all uses it sees (you only have to change the uses, defs are all linked together and thus already fixed by the updater). Right now it only does that if they have no defining access. Make it skip blocks already in the visited set (the

...tion. Is there a something I can do to prevent this memory leak? Any help would be greatly appreciated. By the way, if you execute the code, please run it in a new R session. # Start of code ================================================================ # Function that returns memory being used MemoryUsed <- function(){ pid <- Sys.getpid() system(paste0("top -n 1 -p ", pid, " -b"), intern = TRUE)[c(7,8)] } # Initial memory (VIRT memory equals about 400,000 bytes on my machine) MemoryUsed() # Create a large list of large data, remove it, and perform garbarge collection...

On Tue, Dec 19, 2017 at 9:10 AM, Siddharth Bhat via llvm-dev < llvm-dev at lists.llvm.org> wrote: > I could be entirely wrong, but from my understanding of memorySSA, each > def defines an "abstract heap state" which has the coarsest possible > definition - any write will be modelled as a "new heap state". > This is true for def-def relationships, but

Hi guys, I think I have run into another CachingMemorySSAWalker cache bug. It's a bit tricky to reproduce, so I'd like to start by trying to show you what is happening when running EarlyCSE with my local changes to use MemorySSA. I've attached a debug log that shows that the value returned by getClobberingMemoryAccess(Inst) after a call to removeMemoryAccess is wrong. The

I've put my changes to EarlyCSE that trigger this case up on phab here: http://reviews.llvm.org/D19821. These changes depend on http://reviews.llvm.org/D19664 so that will need to be applied first. With these changes applied, the original attached .ll file should trigger this bug when compiled with opt -early-cse -early-cse-use-memoryssa On 5/2/2016 2:34 PM, Daniel Berlin wrote: >

Hi, I have a question about how llvm MemorySSA works, as seems I misunderstand something. Consider following code snippet and corresponding IR with MemorySSA annotations (got with opt -print-memoryssa) void foo(int* b) { int a = 0; int d = 12; if (b) { a = 42; d = 32; } int c = a; int e = d; } ; Function Attrs: noinline nounwind optnone uwtable

Hey All, I've come across what I believe to be a bug in MemorySSA. George, I wasn't sure if this was a known issue that you'll be addressing in your upcoming walker caching changes or not, so I haven't investigated it very much. The test case is attached. The bug is that the defining access for the second load is set to the loop MemoryPhi node instead of being liveOnEntry as

Dear Daniel Berlin, I just tried MemorySSA analysis and get the next IR. However, I feel confused by the result. Specifically, why instruction *%3* relates to a *MemoryDef*. According to my understanding, I think *%3* should be related to a *MemoryUse*, right? ; Function Attrs: uwtable define void @_Z2f1v() #3 personality i32 (...)* @__gxx_personality_v0 { entry: ; 1 = MemoryDef(liveOnEntry)

This is definitely a caching bug related to this code: 1038 // Don't try to optimize this phi again if we've already tried to do so. 1039 if (!Q.Visited.insert(PHIPair).second) { 1040 ModifyingAccess = CurrAccess; 1041 break; 1042 } We don't differentiate elsewhere between having stopped at a phi because we were path walking and discovered that path

Hi guys, a question about updating memory SSA: Is it expected that e.g insertion of MemoryDef doesn't change all dominated uses? For example test case CreateLoadsAndStoreUpdater produces: define void @F(i8*) { ; 1 = MemoryDef(liveOnEntry) store i8 16, i8* %0 ; 4 = MemoryDef(1) store i8 16, i8* %0 br i1 true, label %2, label %3 ; <label>:2: ;

Hi, try adding some alias analysis to the pipeline: see examples in llvm/test/Analysis/MemorySSA/*.ll for example assume.ll has ; RUN: opt -aa-pipeline=basic-aa -passes='print<memoryssa>,verify<memoryssa>' without basic-aa the memory ssa will safely assume that the stores to %a and %d alias which may be proven disjoint by one of the alias analyses. On Thu, Aug 9, 2018 at 8:37

...prevent this memory leak? Any help would > be greatly appreciated. By the way, if you execute the code, please run it > in a new R session. > > # Start of code > ================================================================ > > # Function that returns memory being used > MemoryUsed <- function(){ > pid <- Sys.getpid() > system(paste0("top -n 1 -p ", pid, " -b"), intern = TRUE)[c(7,8)] > } > > # Initial memory (VIRT memory equals about 400,000 bytes on my machine) > MemoryUsed() > > # Create a large list of large data, remo...

I suspect something is pulling the RHS of the memorydef and caching it for calls it should not be used for. In particular, i suspect we are about to discover we can't cache the results from both versions of getClobberingMemoryAccess together, or that the cache is not always getting consistently written. On Mon, May 2, 2016 at 11:16 AM, George Burgess IV < george.burgess.iv at

On Mon, Apr 27, 2015 at 4:21 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > You can't win here (believe me, i've tried, and better people than me have > tried, for years :P). > No matter what you do, the partitioning will never be 100% precise. The > only way to solve that in general is to pairwise query over the > partitioning. > > Your basic problem is

Let me try to help. On Thu, Feb 8, 2018 at 12:13 PM, Qiuping Yi via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Thanks for your explanation. > > Do you mean that LLVM will not maintain the def-use chain for atomic > variables? > It is not a variable at the LLVM level. At the source level, it is a variable. At the LLVM IR level, it is lowered into memory operations. All

Dear all, I have a few questions regarding the 64 bit version of R and the cache memory R uses. ----------------------------------- Computer & software info: OS: kUbuntu Feasty Fawn 7.04 (64-bit) Processor: AMD Opteron 64-bit R: version 2.7.0 (64-bit) Cache memory: currently 16 GB (was 2 GB) Outcome of 'limit' command in shell: cputime unlimited, filesize unlimited, datasize

Thanks for your explanation. Do you mean that LLVM will not maintain the def-use chain for atomic variables? So it is impossible to directly catch the fact that the load of x at the statement 'data1 = x; ' dependents on data4 (because of the statement x=data4 )? If I want to get such information, may be the only solution is to traverse all the predecessors of the statement 'data1 =

Hi, We started working with rsync to sync data between remote sites. We started seeing many stuck rsync processes. Usually it happens in the ssh stage while the ssh issues a "select" syscall on fd #4 while it is long gone. Here is an example: root@ptsl2171:/root# ps -efwww |grep ekrimer ekrimer 28619 4979 0 Jan28 ? 00:00:00

On 12/20/2017 03:49 PM, Alina Sbirlea via llvm-dev wrote: > +Philip to get his input too. > I've talked with George offline, and here's a summary: > > In D16875 <https://reviews.llvm.org/D16875>, the decision made was: > "The LLVM spec is ambiguous about whether we can hoist a non-volatile > load above a volatile load when the loads alias. It's probably