similar to: Is there any relationship between IR instruction and execution time

Hi Matt, Thanks you so much for the reply! I've tried the llvm-mca, it is helpful. I was wondering whether the llvm-mca support the assembly code for the ARM? I cross-compile the test file for ARM like that: clang test.c -O2 -target arm-linux-gnueabihf -static -S -o test.s If I want to check the performance using llvm-mca, is there any option of "-mcpu" for ARM ? Thanks, Yin

Hi Yin, MCA does support the –mcpu and –mtriple options. We have one arm test in llvm/test/tools/llvm-mca/ARM for a cortex-9, which is an Out of Order chip. Hope that helps! -Matt From: Yin Liu <yinliu.tiger at gmail.com> Sent: Tuesday, May 8, 2018 2:49 PM To: Davis, Matthew <Matthew.Davis at sony.com> Cc: llvm-dev at lists.llvm.org Subject: Re: [llvm-dev] Is there any relationship

Hi All, I would like to use llvm-mca to estimate the IPC of a given code region. I am interested in the library version (https://reviews.llvm.org/D50929?id=162210 <https://reviews.llvm.org/D50929?id=162210>) but I have troubles understanding how to use it. Could you please point me to some documentations or (better) some code examples if any? Reading the documentation

Hi Lorenzo, I’ll answer the first question you have: > I would like to use llvm-mca to estimate the IPC of a given code region. I am interested in the library version

Hi Sjoerd, On Fri, May 3, 2019 at 8:19 AM Sjoerd Meijer via llvm-dev < llvm-dev at lists.llvm.org> wrote: > > I read that out-of-order cores are supported. How about in-order cores? > Would it be easy/difficult to add support for that? > > Cheers, > Sjoerd. > > I don't think that it would be difficult to support in-order superscalar cores. However, it would

Inspired by https://www.agner.org/optimize/instruction_tables.pdf, which gives us the latency and reciprocal throughput of each instruction in the different architecture of X86, Is there anybody taking the effort to do a similar job for LLVM IR? Thanks! -------------- next part -------------- An HTML attachment was scrubbed... URL:

The summary stats for the xin and yin variables below are correct. However, if I use plot(xin,yin), an exception is thrown saying that "object xin is not found." Also, it is apparent that I can't successfully replace the x and y vectors with values from xin and yin. The four plots on one panel are showing but the range of x and y is only [0,1], and therefore, it seems like an

Hi Duncan, Yes, exactly. However, we need define Opcode MIN/MAX Into ISDOpcodes.h. Do you like to add those two definitions Into the tree? Thanks, Yin -----Original Message----- From: Duncan Sands [mailto:duncan.sands at gmail.com] On Behalf Of Duncan Sands Sent: Tuesday, October 30, 2012 12:10 PM To: Yin Ma Cc: llvmdev at cs.uiuc.edu Subject: Re: [LLVMdev] Any plan to

On Thu, Nov 7, 2013 at 11:02 AM, Yin Ma <yinma at codeaurora.org> wrote: > Hi John, > > > > It seems the dereferencing a NULL pointer is undefined behavior but > > Calling a function through a null pointer seems o.k. > What is the well defined behavior of calling a null function pointer? > > > If so , for this place, we need comment out the check. >

Hi John, It seems the dereferencing a NULL pointer is undefined behavior but Calling a function through a null pointer seems o.k. If so , for this place, we need comment out the check. http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#232 look at Notes from the October 2003 meeting. Yin From: John Criswell [mailto:criswell at illinois.edu] Sent: Wednesday,

Hi Yin, > To use select, usually, there is a compare before select. > Presence of comparison will disable some opportunities to > optimize some code. Select and Compare is not associative > neither. at the IR level LLVM already has pattern matching helpers for identifying min/max idioms, here is part of a transform using this, from InstructionSimplify.cpp: // Signed variants

Hi I found basically all llvm libraries are statically linked into each executable and LLVMgold.so, This make the clang/llvm package larger and larger with a lot of duplicated code. If I build debug version, the disk space required is even larger. Is there any particular reason to keep doing this way? If we separate several shared libraries something like libclang.so, libllvm.so and let

Hi Yin, I second David's words. I use shared libs myself on debug builds, but static builds with gold on a local disk is pretty feasible. Before I used gold, I had to have 16GB of RAM on my laptop, now I need less than 8GB for static builds. On 28 January 2016 at 23:58, Yin Ma via cfe-dev <cfe-dev at lists.llvm.org> wrote: > It is O.K. I just hope BUILD_SHARED_LIBS=ON is tested

Hi Duncan, To use select, usually, there is a compare before select. Presence of comparison will disable some opportunities to optimize some code. Select and Compare is not associative neither. Thanks, Yin -----Original Message----- From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On Behalf Of Duncan Sands Sent: Tuesday, October 30, 2012

Hello, As is known to all, there is a relationship between program's instructions and its execution time. In other words, we can estimate the execution time based on the number of program instructions. I'm curious about what the relationship between IR instruction and execution time. I know the number of program instructions and the execution time is highly related to the platform and

On 11/6/13 6:36 PM, Yin Ma wrote: > > Hi, > > For a small case, that calls NULL pointer function. LLVM explicitly > converts > > It to a store because it thinks it is not reachable like calling > undefvalue. > > In InstCombineCalls.cpp:930 > > I think it is not a right approach because calling null pointer function > > Will segfault the program.

Hi David, I assume you have a powerful machine. Our drive space is on network mounted machined by IT department. The machine is default Ubuntu setup with 8 cores. Shared build is showing huge advantage due to size reduction. I will try those two debug options to see how it works. Thanks, Yin From: David Blaikie [mailto:dblaikie at gmail.com] Sent: Thursday, January 28, 2016

----- Original Message ----- > From: "Yin Ma" <yinma at codeaurora.org> > To: "Andrew Trick" <atrick at apple.com> > Cc: llvmdev at cs.uiuc.edu > Sent: Thursday, March 14, 2013 4:21:50 PM > Subject: Re: [LLVMdev] Suggestion About Adding Target Dependent Decision in LSR Please > > > > > > Hi Andy, > > > > Actually,

On Thu, Jan 28, 2016 at 3:06 PM, Jonathan Roelofs <jonathan at codesourcery.com > wrote: > > > On 1/28/16 4:00 PM, Yin Ma via cfe-dev wrote: > >> Hi David, >> >> I assume you have a powerful machine. Our drive space is on network >> mounted >> >> machined by IT department. The machine is default Ubuntu setup with 8 >> cores. >>

Hi, For a small case, that calls NULL pointer function. LLVM explicitly converts It to a store because it thinks it is not reachable like calling undefvalue. In InstCombineCalls.cpp:930 I think it is not a right approach because calling null pointer function Will segfault the program. Converting to a store will make program pass Silently. This changes the behavior of a program.