search for: optimizating

Hi Mark, This will workaround the problem of "default" branch restriction on the switch instruction. The trouble with this technique is that it will trump later optimization phases such as constant propagation. When a block was part of a case, because of the knowledge of the case value, the block was a candidate for better optimization. However, when we move the body of the case into

I think this is a missed optimization, but maybe I'm missing some significant piece of knowledge(!) as to why this might not be optimizable :) Test case... int A; // some global int B; // some global void Test(int *Out) { *Out = A; // Can't this be optimized away? *Out = B; }; The LLVM backend (tested 3.1 and 3.0 online demo) doesn't optimize

On 11/11/2015 9:36 AM, Hal Finkel wrote: > ----- Original Message ----- >> From: "Krzysztof Parzyszek" <kparzysz at codeaurora.org> >> >> Yeah, the remark about devices I made in my post was a result of a >> "last-minute" thought to add some rationale. It doesn't actually >> apply >> to SROA, since there are no devices that are

On Jul 17, 2013, at 10:09 PM, Milind Chabbi <Milind.Chabbi at rice.edu> wrote: > Hi Mark, > > This will workaround the problem of "default" branch restriction on > the switch instruction. The trouble with this technique is that it > will trump later optimization phases such as constant propagation. > When a block was part of a case, because of the knowledge of

Hi, If the function was called Test(&B) then the first store would affect the second load. Tim. On Fri, Nov 16, 2012 at 11:58 AM, AnonW <wayne.phillips at gmail.com> wrote: > I think this is a missed optimization, but maybe I'm missing some significant > piece of knowledge(!) as to why this might not be optimizable :) Test > case... > > int A; // some global

Hi Milind, Maybe you could annotate the default case value as metadata to the swith instruction. Thanks Hongbin On Thu, Jul 18, 2013 at 1:09 PM, Milind Chabbi <Milind.Chabbi at rice.edu>wrote: > Hi Mark, > > This will workaround the problem of "default" branch restriction on > the switch instruction. The trouble with this technique is that it > will trump later

I'm glad you see the potential of this document. It is very important that everybody joins in and add their pennies so that the document eventually reflects the real experience of people who have actually tried and studied these things, and who are familiar with LLVM IR from using and implementing it for a long time. I sort of hope that this document will one day cover almost all LLVM IR

Hongbin Can you elaborate more on your suggestion? I am not sure I fully understand what you suggested. -Milind On Wed, Jul 17, 2013 at 11:11 PM, Hongbin Zheng <etherzhhb at gmail.com> wrote: > Hi Milind, > > Maybe you could annotate the default case value as metadata to the swith > instruction. > > Thanks > Hongbin > > > On Thu, Jul 18, 2013 at 1:09 PM,

Recently I posted a patch to migrate certain GEPs between basic blocks in cases where doing so would improve the ability of instcombine to merge into more complicated addressing mode (r209049 and r209065). After some build to failures it was rolled back. I now have a patch that no longer causes the regressions I was seeing, but it also no longer can optimize the case I was trying to optimize. As

Just briefly looking over the document, I really like the content. I'm now starting to see a really good "fit" for this document: a "guide for language frontend implementers" illustrating basic techniques along with a discussion of implementation decisions regarding the lowering of certain constructs. I don't think that we currently have any documentation targeted at

James Henderson via llvm-dev <llvm-dev at lists.llvm.org> writes: > Maybe it's just because I work in code around the binary file formats > almost exclusively, but unsigned (or more often uint64_t) is FAR more > common than int everywhere I go. I don't have time right now to read > up on the different links you provided, and I expect this is covered > in them, but it

Hi,     I am planning to follow the steps to install LLVM for the ARM-target (Processor: Xscale, Architecture: armv5te):   1. Install binutils-2.21 (downloaded from gnu.org)   Steps:   $ ./configure --target=arm-unknown-linux-gnueabi --program-prefix=arm- --prefix =/llvm/arm --with-sysroot=/llvm/arms/sys-root   $ make   $ make install   2. Install LLVM   Steps   $ ../llvm-src/configure

On Sat, Nov 30, 2013 at 11:20 PM, Mikael Lyngvig <mikael at lyngvig.org> wrote: > I'm glad you see the potential of this document. It is very important > that everybody joins in and add their pennies so that the document > eventually reflects the real experience of people who have actually tried > and studied these things, and who are familiar with LLVM IR from using and

I have some LLVM IR after the optimization passes defined in createStandardModulePasses with the optimization level set to 3. It contains what appears to me to be an easily optimizable branch statement. In particular, note in the code below that at the end of the "loop" BasicBlock that there is a conditional branch where in the false case, it branches to the label

On Jan 1, 2011, at 8:29 PM, akramul azim wrote: > Hi, > I am planning to follow the steps to install LLVM for the ARM-target (Processor: Xscale, Architecture: armv5te): > > 1. Install binutils-2.21 (downloaded from gnu.org) > > Steps: > > $ ./configure --target=arm-unknown-linux-gnueabi --program-prefix=arm- --prefix > =/llvm/arm

Hi Milind, My suggestion just for your concern that if you eliminate the default block, a block associated with a case value will become the default block of the swhich instruction, since a switch instruction always requires a default block. But when a block associated with a case value become the default block, the associated case value is lost and may confuse the later optimizations such as

> On Jul 23, 2018, at 3:40 PM, Alex Bradbury via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > On 23 July 2018 at 11:56, Arsenault, Matthew via llvm-dev > <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: > >> Hi, >> >> >> The specification for the llvm.minnum/llvm.maxnum intrinsics is too unclear >> right

The thread here should help. http://lists.cs.uiuc.edu/pipermail/llvmdev/2010-May/031624.html On May 28, 2010, at 6:35 AMPDT, Curtis Faith wrote: > I have some LLVM IR after the optimization passes defined in createStandardModulePasses with the optimization level set to 3. It contains what appears to me to be an easily optimizable branch statement. > > In particular, note in the code

e, elemental, is a stack for the data web there are 4 components: earth, air, fire, water earth is a pure-ruby RDF triple-store, with a fs backend. no dependencies on 3rd party databases, just add filesystem (tm). theres also a ram backend built with the Mongrel URI-classifier trie as the primitive datastructure. from these two it should be easy to extrapolate how to write a memcached/hadoop

...and stackmaps features are critical for managed runtimes. However, directly supporting these features in a custom IR is simply more convenient. It takes more time to make design changes to LLVM IR vs. a custom IR. For example, LLVM does not yet support TBAA on calls, which would be very useful for optimizating around patchpoints and runtime calls. >> >> Prior to FTL, JavaScriptCore had no dependence on the LLVM project. Maintaining a dependence on an external project naturally has integration overhead. >> >> So, while LLVM is not the perfect JIT IR, it is very useful for JIT dev...