search for: unoptimized

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}, metadata...

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

...); } } 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 project I can send out if anyone's interested, but it's just the above source file and this makefile: .PHONY: all optimized unoptimized clean all: optimized unoptimized grep external *.s optimized: ./clang -S -O1 example.c -o example-optimized.s unoptimized: ./clang -S -O0 example.c -o example-unoptimized.s clean: rm -f *.s When run, I get this output: $ make ./clang -S -O1 example.c -o example-optimized.s ./cl...

...e /usr/bin/gcc -E -o huffman.i huffman.c preprocess decompress.c to become a preprocessed C file /usr/bin/gcc -E -o decompress.i decompress.c preprocess bzlib.c to become a preprocessed C file /usr/bin/gcc -E -o bzlib.i bzlib.c Phase: Translation compile bzip2.i to become an unoptimized LLVM bitcode file bzip2.i has been deleted compile crctable.i to become an unoptimized LLVM bitcode file crctable.i has been deleted compile randtable.i to become an unoptimized LLVM bitcode file randtable.i has been deleted compile compress.i to become an unoptimized LLVM bitcode...

...; 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 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? >> > > It's interesting to me that there's a big difference...

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 intrinsic functions. 2) Mapping between the variables of the...

...efore the next function appears. This also means the global symbol table changes as we process functions. So what I need to do is somehow clone the final module (so I capture all of the needed global symbols) and then replace the functions in the cloned module (which have been optimized) with the unoptimized LLVM IR. So it seems I need to do something like this: 1. Call CloneFunction for each function as it comes across to LLVM. This captures the unoptimized LLVM IR. 2. Call CloneModule at the end of all processing to capture all globals. 3. ??!? 4. Profit! The ??!? is something like, replace...

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

...onverting 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 problem is that an unoptimized call to sqrt(n) in libm will produce a NaN, at least in the implementations I have access to. So this particular choice changes the behavior of optimized versus unoptimized code, which of course is allowable, but probably to be avoided when possible. However, there's a de facto standard of pr...

> 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 -> Exe...

...? I need to save off the >>> text at >>> a certain point and spit it out later, after other optimizations >>> have >>> run. But I need to spit out the original text, not the optimized >>> version. Is it possible to explain intended use of original unoptimized version ? >>> You can use CloneFunction (in llvm/Transforms/Utils/Cloning.h) to >> duplicate a function within a module. >> >> That said, I'm not completely sure what you're trying to do, so I >> don't know if that's what you're looking for. &gt...

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 IR is...

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 is a OK), but we want to make the fin...

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: https://github.com/dibyendumajumdar/ravi/blob/master/include/ravi_...

.... I force native code generation calling ExecutionEngine::getPointerToFunction for each function on the module. This is on x86/Windows/MinGW. The only pass is TargetData, so no fancy optimizations. I don't think that a static compiler (llvm-gcc, for instance) needs so much time for generating unoptimized native code for a similarly sized module. Is there something special about the JIT that makes it so slow? -- Óscar

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 x3 times faster to decode than x265 (output to .ppm file), in average 10ms vs 30ms. As a reminder, x265 is ultra o...

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