Displaying 20 results from an estimated 4000 matches similar to: "Differentiate array access at IR level"
2020 Apr 23
2
Incorrect behavior in the LLVM dependence analyzer
Hi all,
I am trying to use the dependence analyzer in a pass that I am writing and I was surprised to see an incorrect behavior when I try to query DependenceInfo for dependences between instructions. Specifically, if the two instructions are loads/stores accessing an array in a loop, the depend() method would return a dependence regardless of the order of instructions specified. (i.e. if the two
2020 Mar 18
2
valid BasicAA behavior?
As far
Am Mi., 18. März 2020 um 11:34 Uhr schrieb Chawla, Pankaj
<pankaj.chawla at intel.com>:
> >> There seems to be a bug in DI, see Felipe's answer.
> Maybe I missed something. There seems to be no resolution to the problem. How can DA fix this without help from alias analysis?
DependenceInfo is not using the AA interface correctly. Either DI has
to be fixed, or another
2015 Jan 13
2
[LLVMdev] question about enabling cfl-aa and collecting a57 numbers
Hi folks,
Moving the discussion to llvm.dev.
None of the changes we talked earlier help.
Find attached the C source code that you can use to reproduce the issue.
clang --target=aarch64-linux-gnu -c -mcpu=cortex-a57 -Ofast -fno-math-errno test.c -S -o test.s -mllvm -debug-only=licm
LICM hoisting to while.body.lr.ph: %21 = load double** %arrayidx8, align 8, !tbaa !5
LICM hoisting to
2013 May 30
3
[LLVMdev] Expected behavior of calling bitcasted functions?
Hi,
I'm not sure what the expected behavior of calling a bitcasted function is. Suppose you have a case like this (which you get on the source level from attribute alias):
@alias_f32 = alias bitcast (i32 (i32)* @func_i32 to float (float)*)
define internal i32 @func_i32(i32 %v) noinline nounwind {
entry:
ret i32 %v
}
define void @bitcast_alias_scalar(float* noalias %source, float* noalias
2015 Jan 14
2
[LLVMdev] question about enabling cfl-aa and collecting a57 numbers
Can you send me actual LLVM IR or a preprocessed source from using -E?
I don't have a machine handy that has headers that target that arch.
On Tue Jan 13 2015 at 4:33:29 PM Daniel Berlin <dberlin at dberlin.org> wrote:
> Anything other than noalias or mustalias should be getting passed down the
> stack, so either that is not happening or CFL aa is giving better answers
> and
2020 Mar 19
2
valid BasicAA behavior?
Am Mi., 18. März 2020 um 18:15 Uhr schrieb Chawla, Pankaj
<pankaj.chawla at intel.com>:
>
> >> DependenceInfo is not using the AA interface correctly. Either DI has to be fixed, or another method added to AA that gives additional guarantees. Please see the bug report for details.
>
> Thanks for updating the bug report but GetUnderlyingObject() doesn't help in this case.
2015 Jan 14
4
[LLVMdev] question about enabling cfl-aa and collecting a57 numbers
Inline
- George
> On Jan 14, 2015, at 10:49 AM, Daniel Berlin <dberlin at dberlin.org> wrote:
>
>
>
>> On Tue, Jan 13, 2015 at 11:26 PM, Nick Lewycky <nlewycky at google.com> wrote:
>>> On 13 January 2015 at 22:11, Daniel Berlin <dberlin at dberlin.org> wrote:
>>> This is caused by CFLAA returning PartialAlias for a query that BasicAA can
2016 Mar 24
3
Polly as an Analysis pass in LLVM
On 03/23, Hongbin Zheng wrote:
> Hi Johannes,
>
> On Mon, Mar 21, 2016 at 6:35 PM, Johannes Doerfert <
> doerfert at cs.uni-saarland.de> wrote:
>
> > Hey Utpal,
> >
> > First of, I think you made nice process here and have some very good
> > ideas of what we could do in the future.
> >
> > [NOTE: I CC'ed some people that have shown
2016 Mar 21
3
Polly as an Analysis pass in LLVM
Hey Utpal,
First of, I think you made nice process here and have some very good
ideas of what we could do in the future.
[NOTE: I CC'ed some people that have shown interest in this topic but I
might have forgotten some, therefor I also added the llvm-dev list.]
For the upcoming GSoC proposal we should slow down a little bit and
reevaluate our goals. After talking to a couple of LLVM and
2015 Jan 14
3
[LLVMdev] question about enabling cfl-aa and collecting a57 numbers
On 13 January 2015 at 22:11, Daniel Berlin <dberlin at dberlin.org> wrote:
> This is caused by CFLAA returning PartialAlias for a query that BasicAA
> can prove is NoAlias.
>
One of them is wrong. Which one?
I'm not sure from your description that this is a chaining issue.
PartialAlias doesn't chain and isn't supposed to, it's a final answer just
like NoAlias and
2015 Jan 14
3
[LLVMdev] question about enabling cfl-aa and collecting a57 numbers
Oh, sorry, i didn't rebase it when i changed the fix, you would have had to
apply the first on top of the second.
Here is one against HEAD
On Wed, Jan 14, 2015 at 12:32 PM, Ana Pazos <apazos at codeaurora.org> wrote:
> Daniel, your patch does not apply cleanly. Are you on the tip?
>
> The code I see there is no line if (QueryResult == MayAlias|| QueryResult == PartialAlias)
2014 Sep 18
2
[LLVMdev] [Vectorization] Mis match in code generated
Hi Nadav,
Thanks for the quick reply !!
Ok, so as of now we are lacking capability to handle flat large reductions.
I did go through function vectorizeChainsInBlock() (line number 2862). In
this function,
we try to vectorize if we have phi nodes in the IR (several if's check for
phi nodes) i.e we try to
construct tree that starts at chains.
Any pointers on how to join multiple trees? I
2015 Feb 07
3
how to draw paired mosaic plot?
If there are many character variables,and I want to get the mosaic plot of every pair of each variable,how to do then?
If the variables are numeric, I can use pairs to get paired scatter plot.
But as to the character variables, how to get the "paired mosaic plot"?
Many thanks.
--
QQ: 1733768559
At 2015-02-07 17:04:26,"Jim Lemon" <drjimlemon at gmail.com>
2015 Jul 16
4
[LLVMdev] Improving loop vectorizer support for loops with a volatile iteration variable
----- Original Message -----
> From: "Hal Finkel" <hfinkel at anl.gov>
> To: "Chandler Carruth" <chandlerc at google.com>
> Cc: llvmdev at cs.uiuc.edu
> Sent: Thursday, July 16, 2015 1:58:02 AM
> Subject: Re: [LLVMdev] Improving loop vectorizer support for loops
> with a volatile iteration variable
> ----- Original Message -----
> >
2014 Sep 19
3
[LLVMdev] [Vectorization] Mis match in code generated
Hi Arnold,
Thanks for your reply.
I tried test case as suggested by you.
*void foo(int *a, int *sum) {*sum =
a[0]+a[1]+a[2]+a[3]+a[4]+a[5]+a[6]+a[7]+a[8]+a[9]+a[10]+a[11]+a[12]+a[13]+a[14]+a[15];}*
so that it has a 'store' in its IR.
*IR before vectorization :*target datalayout =
"e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128"
target triple =
2016 May 07
3
[GSoC 2016] Introduction - Polly as an Analysis pass in LLVM
Dear All,
I am glad to be part of GSoC 2016 with LLVM organization. I am a first year
PhD student at IIT Hyderabad, India and my research area is compiler
optimizations using polyhedral model.
My GSoC 2016 project is to implement Polly as an Analysis pass in LLVM [1].
We have a discussion on Polly-dev mailing list [2] on taking a better
approach to implement this project. Based upon this
2016 Jul 21
3
Fwd: Problem of array index manipulation collection of LLVM IR
Hi there,
I am a newbie of llvm and here is my question situation. Assume that there
is a function F which contains a loop named L, a array b[100]. I want to
collect the statistical information of array index operation op(i) (take
add and mul simply) of i in the loop L. Pseudocode lists below.
void F(arg1, arg2){
int b[100];
for(int i=0; i<n; i++){
op1(i);
op2(i);
2007 Sep 13
5
Apache mod_proxy_balancer hang on high traffic hour
more info
just 1 server
webserver + appserver + dbserver
On 9/14/07, Yan Meng <dreamwords at gmail.com> wrote:
>
> Hi, Guys
>
> Our team is running a web2.0 finance site in China
>
> http://www.caibangzi.com/
>
> We use APACHE + mod_proxy_balancer + mongrel to deploy our application, it
> workd super in the past few monthes.
>
> However, just from last
2016 Mar 23
0
Polly as an Analysis pass in LLVM
Hi Johannes,
On Mon, Mar 21, 2016 at 6:35 PM, Johannes Doerfert <
doerfert at cs.uni-saarland.de> wrote:
> Hey Utpal,
>
> First of, I think you made nice process here and have some very good
> ideas of what we could do in the future.
>
> [NOTE: I CC'ed some people that have shown interest in this topic but I
> might have forgotten some, therefor I also added the
2014 Sep 18
2
[LLVMdev] [Vectorization] Mis match in code generated
Hi,
I am trying to understand LLVM vectorization implementation and was looking
into both loop and SLP vectorization.
test case 1:
*int foo(int *a) {int sum = 0,i;for(i=0; i<16; i++) sum += a[i];return
sum;}*
This code is vectorized by loop vectorizer where we calculate scalar loop
cost as 4 and vector loop cost as 2.
Since vector loop cost is less and above reduction is legal to