search for: unoptimal

I am seeing this with llvm generated code, and before also saw this with gcc generated code. In unoptimized code, debugger would say something like this when the variable isn't used any more, but is still in scope: (gdb) p this $11 = <optimized out> Looking at the debug records, I don't see what is wrong, for example: call void @llvm.dbg.declare(metadata !{%struct.Object* %1},

Dear All, I am Zahurul Islam. I have found LLVM always generate optimize byte code, but I want to stop this. Actually, I want unoptimized LLVM assembly code from C code. Please help me to do that. regards, Zahurul Islam BRAC University Dhaka,Bangladesh

Hi Devs, Consider testcase here https://godbolt.org/z/qHZzqw When optimization is O1 or above it produces unoptimized code because it calls __tls_get_address in loops. While with optimization disabled It produce single call to __tls_get_address outside of loop. is this a missed optimization by llvm? ./Kamlesh

I've been chasing down a bug for a few days in some RTOS code I'm building with clang. In the end it comes down to this code: void external(void); void test(char *x) { x--; if (!x) { external(); } } When compiled for ARM with TOT clang (r183249) at -O1 or greater, no calls to 'external()' appear in the output code at all. I have an example

Hi, I've restarted my Elsa/LLVM project after three months of having real life intrude. I upgraded my LLVM source to the current trunk. I had to make a few changes to my source, e.g. LLVMFoldingBuilder became IRBuilder and several instances of "new" became "Create". Now, a test case that previously succeeded fails. I run the following script: #!/bin/sh if [ 1 -ne 0 ]

On Thu, Oct 31, 2019 at 11:17 AM Jorg Brown via llvm-dev < llvm-dev at lists.llvm.org> wrote: > On Thu, Oct 31, 2019 at 8:50 AM kamlesh kumar via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> Hi Devs, >> Consider testcase here >> https://godbolt.org/z/qHZzqw >> When optimization is O1 or above it produces unoptimized code >> because it

Hi, I am planning to use LLVM for a compiler validation project that checks if the optimized version of the code is the correct translation of the unoptimized code. And I have a couple of questions. I need two pieces of information from the compiler: 1) Some kind of mapping between the structure of the unoptimized and optimized code. It seems, that can be obtained via the llvm.dbg.stoppoint

On Wednesday 09 July 2008 12:16, Eli Friedman wrote: > On Wed, Jul 9, 2008 at 9:56 AM, David Greene <dag at cray.com> wrote: > > I seem to recall havbing asked this before but I can't find it by > > searching. > > > > What's the right way to clone a Function? I need to save off the text at > > a certain point and spit it out later, after other

On 02/02/2014 01:48, David Chisnall wrote: > In most calling conventions, this is a callee-save register. After its last use, the register allocator may reuse that register. On x86 and ARM, the register that contains this is also (usually) the register used for But the rule "after the last use, the register allocator may reuse it" is also introduced by llvm, since register

My colleague Will Schmidt recently discovered (http://llvm.org/bugs/show_bug.cgi?id=21048) that the LLVM optimizers are converting sqrt(n), where n is negative, into 0.0. Now, as Sanjay pointed out, the value of sqrt(n) for negative n other than -0.0 is undefined according to the C99 standard, so this is allowable behavior. But I think that it's not necessarily good behavior, nonetheless.

> The fast and local register allocators are meant to be used on unoptimized code, a 'Debug build'. While they do work on optimized code, they do not give good results. Their primary goal is compile time, not code quality. Yes, we have a somewhat uncommon use case. It is fine to spend time optimizing bitcode (LTO is a OK), but we want to make the final IL -> Executable translation

On Jul 9, 2008, at 10:43 AM, David Greene wrote: > On Wednesday 09 July 2008 12:16, Eli Friedman wrote: >> On Wed, Jul 9, 2008 at 9:56 AM, David Greene <dag at cray.com> wrote: >>> I seem to recall havbing asked this before but I can't find it by >>> searching. >>> >>> What's the right way to clone a Function? I need to save off the

Hi everyone, Llvm-gcc compiles the programs into bytecodes with some optimizations. How can I get unoptimized bytecodes? Thanks. Regards, -Ying -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20070530/5f793e95/attachment.html>

Hello, I m trying to test individual O3 optimizations/ replicating O3 behavior on IR. I took unoptimized IR (O0), used disable-o0-optnone via (*clang -O0 -Xclang -disable-O0-optnone*). I read somewhere about *clang -O1 -Xclang -disable-O0-optnone,* so I also tested on this initial IR. I have observed by using individual optimizations, the performance (i.e time) is better when the base/initial

Hi, I am interested in obtaining LLVM IR without any optimization performed on it.( IR obtained from cfrontend's AST). Is this LLVM IR in SSA form? Secondly, I want to make a transformation on this unoptimized IR, and convert it back to C. I believe llc -c does that. Thirdly, is it possible to use LLVM tool suite on LLVM IR that's not in SSA form, if we have such LLVM so.

On May 17, 2010, at 9:09 PM, Rafael Espindola wrote: >> The fast and local register allocators are meant to be used on unoptimized code, a 'Debug build'. While they do work on optimized code, they do not give good results. Their primary goal is compile time, not code quality. > > Yes, we have a somewhat uncommon use case. It is fine to spend time > optimizing bitcode (LTO

Hi Praveen, On Sat, 10 Aug 2019 at 21:05, Praveen Velliengiri <praveenvelliengiri at gmail.com> wrote: > > Could you please send me your unoptimized and expected optimized code? The default implementation only contains some transformations. It would be helpful to know what you are actually trying. > Optimize Module is just a function object. > You can view the code here:

While compiling some sources, translating from my compiler's IR to LLVM using the C++ API requires 2.5 seconds. If the resulting LLVM module is dumped as LLVM assembler, the file is 240,000 lines long. Generating LLVM code is fast. However, generating the native code is quite slow: 33 seconds. I force native code generation calling ExecutionEngine::getPointerToFunction for each function on

Hello, I am very slowly working on the NHW Project.I recently made a speed comparison with x265 and wanted to share it with you. On my processor Intel Core i5-6400, in average the NHW encoder (totally unoptimized) is x10 times faster to encode than x265 (png decoding time removed), in average 30ms vs 300ms for a 512x512 24bit color image, and in average the NHW decoder (totally unoptimized) is

I downloaded the latest 1.8 (27922) but got some segmentation faults. The first one was when it loaded cdr_odb, and so I changed menuselect not to compile that one, but the second one was when it tried to load chan_agent and so I stopped there to see if anyone else was seeing this. The agents.conf is all commented out except for [general] . Anyone know what is happening? Thanks. P.S. I deleted