similar to: llvm 3.9 Alias Analysis result for function's by-ref arguments

Hi, I have an analysis pass which collects information about functions based on their call sites. There are problems I'm facing with processing virtual function calls, namely . How identify virtual call sites in my pass? . How Identify candidate callees for the given virtual call site? For the following example, the information I want to get would be identify call of F and as a possible

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

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

On Fri, Sep 21, 2012 at 3:08 PM, Welson Sun <welson.sun at gmail.com> wrote: > OK, with the restrict type qualifier, it is a little bit better: > > The IR's function signature becomes: > define void @foo(i32* noalias %a, i32* noalias %b, i32* noalias %c) nounwind > { > > Now the AA result: > Function: foo: 13 pointers, 0 call sites > NoAlias: i32* %a,

Hi, all According to the document "LLVM Alias Analysis Infrastructure", I evaluated the AA performance by using the paramenters '-basicaa -ds-aa -anders-aa'. The source code 'test.c' is listed as follow: //------------=== Source code ===------------// #include<stdlib.h> typedef struct { int x; int y; } Location; Location* getNewLocation(int x, int y) {

On 2009-06-29 11:16, Wenzhi Tao wrote: > Hi, all > > According to the document "LLVM Alias Analysis Infrastructure", I > evaluated the AA performance by using the paramenters '-basicaa -ds-aa > -anders-aa'. The source code 'test.c' is listed as follow: > [...] > The whole process: > > llvm-gcc -emit-llvm -O0 -c test.c -o test.bc > > opt

Here is the result of running mem2reg then basicaa, it is even worse: (%a should be alias to %0, and partial alias to %3) opt -mem2reg -basicaa -aa-eval -print-all-alias-modref-info < foo.s > /dev/null Function: foo: 6 pointers, 0 call sites NoAlias: i32* %a, i32* %b NoAlias: i32* %a, i32* %c NoAlias: i32* %b, i32* %c PartialAlias: i32* %1, i32* %a NoAlias:

to compile it to bitcode I give the following command : llvm-gcc -emit-llvm -c -o s.bc s.c and then I run different alias analysis passes like -anders-aa, -basicaa using following: opt -anders-aa -aa-eval -print-all-alias-modref-info s.bc From this I get the following output: Function: main: 8 pointers, 1 call sites NoAlias: i32* %retval, i32** %j NoAlias: i32* %retval, i32**

On Fri, Jun 12, 2015 at 2:03 PM, Andrew Trick <atrick at apple.com> wrote: > > On Jun 12, 2015, at 1:51 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > > So, you can't have disjoint sets, and have one of set that says "i > access everything". Because it would contain everything :) > > Thus, I assume by your description you meant "we want to

Hi, Using this option I do get all the vars as may alias ie MayAlias: i32* %j.0, i32* %k MayAlias: i32* %i.0, i32* %k MayAlias: i32* %i.0, i32* %j.0 Is there any other analysis which will give them as must aliases. Actually what I want to do is implement a flow sensitive points-to(not alias) analysis and then use that information for some optimizations like PRE. Will that be

----- Original Message ----- > From: "Alex Bradbury" <asb at asbradbury.org> > To: llvm-dev at lists.llvm.org > Cc: "Hal Finkel" <hfinkel at anl.gov> > Sent: Sunday, November 8, 2015 10:30:09 AM > Subject: Re: noalias parameter attribute not currently exploited by alias analysis? > > On 2 November 2015 at 20:20, Alex Bradbury <asb at

Hi Ambika, > to compile it to bitcode I give the following command : > > llvm-gcc -emit-llvm -c -o s.bc s.c > > and then I run different alias analysis passes like -anders-aa, -basicaa > using following: > > opt -anders-aa -aa-eval -print-all-alias-modref-info s.bc alias analysis will work poorly if you don't run any optimizers. The alias analysis passes

Hi Ambika, > Oh m sorry for that mistake as I had points to in mind. > But still what about the following prog: > > int main() > { > int *i,*j,k; > i=&k; > j=&k; > k=4; > printf("%d,%d,%d",*i,*j,k); > return 0; > } > > > here too i dont get <i,j> alias each other. how are you

Hi, On 02/10/2016 01:23 AM, haicheng at codeaurora.org wrote: > Thank you, Mikael. I can reproduce what you saw and am looking into it. Great! > Just curious, why do you run loop-deletion before licm and loop-idiom? As part of our internal testing we use Csmith to generate C-programs and then we run the compiler with random generated compiler flags on that input. This bug was

Hi again! Replying in chronological order: > On Thu, Jul 9, 2020 at 6:51 PM Shuai Wang <wangshuai901 at gmail.com > <mailto:wangshuai901 at gmail.com>> wrote: > > Hey Matt, > > That's awesome. Thank you very much for all the information and > clarification! Just a few follow up questions. Could you kindly shed > some lights on it? Thank

Oh m sorry for that mistake as I had points to in mind. But still what about the following prog: int main() { int *i,*j,k; i=&k; j=&k; k=4; printf("%d,%d,%d",*i,*j,k); return 0; } here too i dont get <i,j> alias each other. Duncan Sands wrote: > Hi ambika, > >> main() { >> int i,*k; >> k =

Hi Welson, the default alias analysis is -no-aa. As the name suggests it just returns MayAlias for everything. Maybe you are using that one? Best wishes, Duncan.

Hello all, I observed that BasicAA alias query returns PartialAlias between different fields of a structure. Following is the test program and -print–all-alias-modref-info output: --- ; test.ll target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" %"type" = type { [10 x i32], i64 } define void

Greetings all, I'm working on refactoring the alias analysis layers to remove the usage of analysis groups and make the logic sharable between old and new pass managers, and I have a couple of questions below. As background, the overall plan that I've discussed with Hal and a few others previously is as follows: - Create an AliasAnalysisManager which is provided by a normal analysis

Hi Yi, I didn't get a chance to run your code. But from the debug information you posted about tbaa alias analysis: Alias Set Tracker: 1 alias sets for 7 pointer values. AliasSet[0x207f860, 7] may alias, Mod/Ref Pointers: (i32* %1, 4), (i32* %x, 4), (i32** %p, 8), (i32** %q, 8), (float* %z, 4), (float** %t, 8), (i32* %2, 4) I guess it is because of the way how TBAA alias analysis treats