Clang windows vs llvm performance. 4 comparison is appended to that.

Clang windows vs llvm performance There are multiple dimensions to compatibility. All in all, this makes Clang/LLVM an excellent compiler toolchain for modern times. LLVM Clang Compilers. By Zachary Turner; Jan 8, 2018; #clang-cl, #lld, #Windows; 18 minute read; One of our goals in bringing clang and lld to Windows has always been to improve developer experience, and what is it that developers want Here are some up-to-date albeit narrow findings of mine with GCC 4. 7 Target: x86_64-pc-windows-msvc See benchmark code: Dear All, Could you please let me know techniques to optimize performance with clang-14. At the same time, adding better support for bare-metal arm into clang’s driver would give other benefits: other clang-based tools, like clang-tidy, would work without extra configuration; Last week I posted a number of fresh GCC vs. k. From bugs to performance to perfection: pushing code quality in mobile apps. Eclipse CDT indexer MSVC’s cl. 24. 0 benchmarking against the open-source LLVM/Clang and AOCC compilers. 8. to help the compiler and close the gap between the msvc and clang performance. This installs and opens the Visual Studio Installer. How does LLVm fit in? I know that it is a C/C++ Compiler, The LLVM testing infrastructure contains three major categories of tests: unit tests, regression tests and whole programs. Hi, I am trying to build a code with OpenMP offloading to nVidia GPU with сlang++: h:\llvm-project-15. LLVM is well known for supporting JIT compilation, and moreover, Clang, LLVM's best-in-class C++ frontend, enables the highly-optimized compilation of C++ code. Layers of GPU computing GPU accelerated apps and libraries CUDA OpenCL AMD proprietary compiler Libclc, LLVM, Mesa, and amdgpu/nouveau AMD proprietary driver NVIDIA proprietary driver Clang Our work NVIDIA GCC is a fine compiler, and can produce code that has pretty much the same performance, if not better, than MSVC. 0\build\Debug\bin\clang++ -fopenmp -fopenmp-targets=nvptx64 --offload-arch=sm_52 --libomptarget-nvptx-bc-path="c:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v11. With LLVM/Clang 14. 0 version so we can manually check our build used the correct compiler (the Visual Studio ClangCL bundled one is version 14) It is completely possible to use a different VS version when using LLVM/Clang. 5x as fast as just /O2. Those flags included: Here is that more extensive round of AOCC 4. 5. It's not going to work perfectly out of the box, especially since we are missing exception-handling support for MinGW. Practically both are well optimized, however, LLVM IR is much more robust and modular, than Replacing the memory allocation subroutines with TC malloc, JE malloc or HOARD malloc all yielded *massive* uplifts in performance, leading to GCC-12 surpassing clang is slightly faster than MSVC at parsing the non templated Visual Studio header files. You seem surprised that gcc beat llvm on your benchmark. 0, make sure to set "i686" to "x86_64" when asked); Install Clang for Windows (64-bit) (currently 5. 2. Controls whether ANSI escape codes are used instead of the Windows Console API to output colored So from the performance perspective, it's gotten rather boring except for cases of targeted CPU tuning or new instruction capabilities being added. Hi All, I have spent a better part of my 32 years on this earth writing Solaris software and more recently leaving that and returning back to Mac OS. libc, which determine the "env" or "abi" part of the target triple). We use clang to compile IR code, then execute the IR in some place. I ran the test many times on both clang and cl to make sure all header We're going to compare three compilers: The Intel C++ compiler, the GNU C++ compiler (g++), and the LLVM clang compiler. The problems occur when I try to call C++ code from C# using P/Invoke. Follow Windows 10 / VS 2017 / Clang 4. exe supports several new command-line flags for C++ module interface and implementation files, detailed here. But that was ~10 years ago and I guess it’s not a common setup. not only improve SPEC. 14, better vcpkg integration, and many more enhancements. I found that the performance of executable from gcc always better than LLVM one. I called clang with the -O2 option as this was the default LLC option, and the difference with -O0 is negligible. Hi, I was wondering if there are plans (in the near future/today) to “port” libc++ to the Windows platform? This would make the project a lot more useful than it is right now, as clang is starting to get better at Windows stuff. Extensions. A plugin makes it possible to run extra user defined actions during a compilation. 1) from the Individual Components tab. I downloaded and installed the Build Tools for Visual Studio 2022. 1 v clang 3. Building and installing the libc 3. exe and the project finally got compiled, but I still know GCC has a 1% to 4% performance advantage over Clang and LLVM for most programs at the O2 and O3 levels, and on average has an approximately 3% performance advantage for SPEC CPU2017 INT Speed. You would use it if you want to compile against the MinGW-w64 runtime. Please see <https://clang-analyzer. exe”, or LLD, the LLVM project’s linker – see below) I also understand that the huge performance gap between LLVM 16 and Apple Clang is likely a temporary situation, but this is perhaps even worse for Homebrew users, because bottles don’t seem to be recompiled due to compiler updates. I think your research thus far shows that swapping between current version of Clang or Use clang: this is the clang driver that understands GCC-like options. Any help would be appreciated. 2 and Clang 3. But if you just want to use the compiler, I suggest using one of the better-supported LLVM/Clang continues to impress with its very competitive and often times leading performance these days over GCC. We use GCC 13 and ld setup with lto. Description of the project: The Clang compiler is part of the LLVM compiler infrastructure and supports various languages such as C, C++, ObjC and ObjC++. My remaining tasks include landing the Mustache support library and Clang-Doc’s Mustache backend, as well as gathering feedback from the LLVM community regarding Clang-Doc’s current output. Clang 17 were tested as what's readily available on Ubuntu 23. CPython, including native modules) so you may have to use it. 28315. h in C code. If NO_COLOR is defined and -fcolor-diagnostics is passed on the command line, Clang will honor the command line argument. gcc_s/O2, GCC has a great performance advantage (more than 10%). This makes many optimizations to be easily performed on the IR. GCC uses its own IR generation where Clang uses LLVM IR. The LLVM tool llvm-profgen can convert output of either Perf or SEP. LLVM/Clang. I wrote a blog post on one of the large LLVM compile-time improvements I worked on this year: How single-iteration InstCombine improves LLVM compile time | Red Hat Developer • "performance measurements that can be used to compare compute-intensive workloads on different computer systems. But as a whole when looking at the C/C++ performance of LLVM Clang 14 vs. The design of LLVM and Clang allows the compiler to be extended with plugins[1]. exe as the compile but failed on CMake configuration (lot’s of library not found, for example clang. Using the libc to link real applications It’s full name is The GNU Compiler Collection, available for Linux, Windows, Clang/LLVM. 04 LTS release will be sticking to GCC 13 while on the LLVM side it should be shipping Clang 18 so it will be interesting to see what performance changes are there for that next six-month compiler update. The latest release includes Clang/LLVM support, CMake 3. Our GCC flash footprint of a stripped application with (–strip-all) is 29402kb. In this article is a look at the GCC 13 vs. 6 version compiler while building c/c++ code on linux machine? Regards Koti Hi, I’ve started investigating the clang source code. 3 comparison appended below. •We will focus on SPEC2017Int rate. Place them both in your system path (accessible for all users). 5\nvvm\libdevice" -Ih:\llvm-project . Hello, I’m developing cross platform C++ library which will be used by both C++ and C# projects. exe clang Clang Static Analyzer. TLDR; Programs compiled with GCC (version 7-12) are taking up to 50% longer to complete vs those compiled by open rouce LLVM based CLang (11-13) and Intel ICX, and closed source Intel ICC compilers. In general, we see clang being faster than gcc on linux/mac, and about as fast as cl. This is how I As we have been seeing on other systems, the latest GCC and LLVM Clang compilers on x86_64 are really delivering neck-and-neck performance. Does anyone know why clang-cl only enables -O2 instead of -O3 with /O2 ? Is it by design? clang version 18. a. Inline functions and link time optimizations. org; Improving Link Time on Windows with clang-cl and lld. A similar GCC 13 vs. What I am trying to achieve is to compile a simpliest hello world application using Clang under Eclipse on a Windows 7 x64 machine. I’ve built LLVM and Clang from source in Windows 10 using Visual Studio (I’ll try again with Ninja at some point). It sounds like you don’t configure your build correctly. For some reasons, we add "-fno-inline" in compile options, which brings very bad performance. The unit tests and regression tests are contained inside the LLVM repository itself under llvm/unittests and llvm/test respectively and are expected to always pass – they should be run before every commit. g. LLVM Clang has made many strides in the past few years where for x86_64 (and AArch64) is largely at parity to the GNU Compiler Collection in terms of the performance of the generated binaries. I would like to add some performance data of LLVM vs. In my test, I get a 40% speedup with ClangCL. fallback mechanism in case we hit a toolchain not well-supported by clang. I’d like to only build the C tools if possible? I found documentation on cmake options for building clang (e. I doubt this works for clang-cl, but I haven't tried that to be honest. exe" is being called. bat). 0 missing stdlib. GCC performance on Intel Meteor Lake. GNU also allows flexible build configuration options to tradeoff between speed and size. Why doesn't clang/llvm optimize this? 4. Clang/LLVM Support. I am looking to have more freedom and flexibility along with producing better quality software. Over the years it has been very reliable for both Unix and Windows however, Cling is heavily used to interact with GCC-compiled codebases and is sensitive to ABI incompatibilities between GCC and Clang with respect to the Itanium ABI specification. Before the IR code takes less than 1ms, after open "-fno-inline", the IR code takes more than 20ms. exe -- Check for working C compiler: C:/Program Files (x86)/LLVM/bin/clang. Windows, and FreeBSD. exe”, or LLD, the LLVM project’s linker – see below) On Windows, I encountered a benchmark where, compiled with clang-cl, -Xclang -O3 produces code about 2. Are there resources available that shows the latest performance numbers of LLVM 4. LLVM Clang compiler performance benchmarks on AArch64. (clang-built-by-clang is a bit faster than clang-built-by-cl on windows; I don’t know how clang-built-by-clang and clang-built-by-gcc on windows compare. Intel Core Ultra 9 285K "Arrow Lake" Windows 11 vs. Tiling optimization gcc vs clang. Key use cases include: - Operating Systems: LLVM and Clang are widely used in operating systems like macOS and FreeBSD. In terms of 600. LLVM Clang compiler performance benchmarks using an AMD Ryzen Threadripper PRO 7995WX (Zen 4) system using the HP Z6 G5 A workstation running Ubuntu One can build and install libc++ together with clang in Windows by setting LLVM_FORCE_BUILD_RUNTIME cmake's variable to ON. I configured the llvm-project with the following parameters: I'm really keen to get clang and LLVM working as they sound great from what I've read. Ubuntu Linux Performance. Hi Ladies and Gents, I've been working on profiling the ins and outs of how alder lake works with You do provide a means of building clang on Windows through the VS Studio solution. I used LLVM_TARGETS_TO_BUILD:STRING=all on cmake to include all the targets (to be able to compare with what Rafael Espindola posted on LLVM-Dev. 0 benchmarking comparison the following compilers were tested: - AOCC 4. 0. exe on windows on our bots. Hi, I did some benchmarking of clang on Windows this morning, just for fun. exe -- works -- Detecting C compiler ABI info -- Detecting C compiler ABI info - done -- Detecting C compile Agenda 1. An external project, AutoFDO, also provides a create_llvm_prof tool which supports Linux Perf output. ) I compiled 4 versions of clang: win32 and /O1 win32 and /O2 win64 and /O1 win64 and /O2 /O1 is Minimize Size (configuration In the future I plan to work on Clang-Doc until an MVP product can be generated and evaluated for the LLVM project. 0 due out in the early months of 2022 will be more performance work with one recent commit in particular showing a lot of promise. 4 comparison is appended to that. This tool uses many parts of Clang and is built into the same driver. 6 builds do have several integrated supported Clang build environments on Windows (e. The following details setting up for and building Clang on Windows using Visual Studio: Get the required tools: Git. ; In the Visual Studio Installer I selected three things: . As part of our ongoing benchmarks of GCC 11 vs. See details of the Nowadays, I compiled two different executable from two compiler (LLVM and gcc), and ran 100,000 times on both of them. Phoronix hosts a bunch of interesting benchmarks in this area. LLVM Clang 16 compiler performance on Raptor Lake as Intel's latest-generation desktop processors. LLVM/Clang on AArch64 is in particularly good standing given the widespread use of Clang for compiling software targeting AArch64 mobile devices, Apple relying on its LLVM/Clang-based compiler stack for ARM, and a lot of other Clang use by Benchmarking Clang on Windows Arm using SPEC CPU 2017 SPEC Rate INT clang-cl consistently performs better than cl across all three optimization levels. For instance, have a look at: Benchmarking LLVM & Clang Against GCC 4. exe”), other parts with Clang, and when linked together (either by MSVC’s linker, “link. Using clang on Windows what program is supposed to be called to do the link step after compilation ? In the Boost toolset for clang, admittedly created for clang on Linux, it appears that the program "link. Also “ found my system much more responsive overall ” very much sounds A snapshot build is something generated by an automated build process, typically invoked by some source code change, where the resulting snapshot build is typically exercised by a set of so-called regression tests to assess said changes. There are several straightforward equivalents between the two compiler front-ends: cl. Our optimzation level is O2 for release builds. I installed LLVM on a clear Windows 10 machine, without anything else. The upcoming Ubuntu 24. - Mobile Platforms: Android’s NDK uses LLVM, and iOS development relies on Clang as its primary compiler. While the performance of LLVM/Clang has improved a lot over the years and for x86_64 and AArch64 can be neck-and-neck with the GCC compiler, the fierce performance battle is not over. I know they are different type of compiler even different architecture. For more information about Clang or LLVM, including information about the latest release, please see the Clang Web Site or the LLVM Web Site. Brief introduction to LLVM’s libc and its current status 2. If you're willing to dig into the guts of the compiler, debug issues, and write patches, that's great. Hot Network Questions What is the correct way on uninstall software on Windows? LLVM AMDGPU for High Performance Computing: are we competitive yet? Vedran Miletić, HITS gGmbH Szilárd Páll, KTH Frauke Gräter, HITS gGmbH. Apart from this, to answer your questions: To get VS to use GCC as a compiler, you'd pretty much need to turn to makefiles or custom build steps all the way. GCC regarding compilation time and overall code generation quality. on Windows, we have -msvc vs -gnu (vs -gnullvm); on Linux, we have mainly -gnu vs -musl, (there are many other environments too, mostly for specific hardware or embedded systems, such as -androideabi, clang file. dll per Mingw-w64 — though historically Microsoft's UCRT LLVM Project News and Details from the Trenches. Let us now get into the GCC Vs Clang head-to-head comparisons between these two If you're on Windows often enough it's useful to how to use and operate the MSVC toolchain (via vcvars. AlmaLinux 10 Beta Running Great With Nice Performance As Free/Community Alternative To RHEL 10. c++; mingw; eclipse-cdt; codeblocks; clang; Share. LLVM and Clang set themselves apart with an architecture optimized for faster compiles. Our ld linktime is ~10min. About; Posts; Tags; llvm. Potentially Breaking Changes ¶ These changes are ones which we think may surprise users when upgrading to Clang 19. c -S -O3 -o - (output native machine code) Run the testsuite: make check-clang; Using Visual Studio. If you are not familiar with Visual Studio’s CMake support, check out how to get started. Clang, however, uses purely an ahead-of-time compilation model, and so we leave on the table performance which might come from dynamic specialization. In general both the GCC and Clang builds run on windows 11. 2 v clang 3. 2 for C++. . Just like Clang, Cling can be extended by plugins. I remember doing so at one point when I was still using Windows, and found my system much more responsive overall. 0. Clang is a part of high-performance debugger. perlbench_s and 602. ) This was Ubuntu gcc 9. 7. e. Clang has an option to select its C++ standard library: -stdlib=libc++ selects the LLVM libc++. Some software only supports MSVC on Windows (e. Commented Dec 15, 2020 at 13:23. 10 Linux plus a look ahead in using the latest GCC 14 and LLVM Clang 18 development snapshots as of this week. So, I have the following questions: Clang is the first-ever open-source C++ compiler that’s ABI-compatible with Microsoft Visual C++ (MSVC) – meaning you can build some parts of your program (for example, system libraries) with the MSVC compiler (“cl. LLVM Clang 16 compiler benchmark comparison will be Compiling your Windows software with ClangCL may lead to better performance (in Release mode). 0 because of the opportunity they pose for disruption to existing code bases. I've just run a successful test with The difference is not much compared to gcc, clang with asserts off is a bit faster than gcc, and with asserts on a bit slower. Note how the Visual Studio ClangCL and the LLVM/Clang versions are different, in this case, we are using the LLVM/Clang 13. Loading It’s time for an update on Clang’s support for building native Windows programs, compatible with Visual C++! We’ve been working hard over the last few months and have improved the toolchain in a variety of ways. 3 running on the same machine vs Windows msvc 19. " I think I downloaded and installed it. UPDATE: GCC 4. " • Family of benchmarks: SPEC2006, SPEC2017. The latest CMake 3. 1. 10 years ago does not seem very relevant, both Windows and VS are very different now. GCC and Clang (the compiler you're referring to when you write LLVM) both support essentially equal features and both cover the entire current standard (C++17). Plugins are supported on unix and darwin Sorry to barge in. GCC 13 vs. exe: error: no such file or directory: ‘/DWIN32’ ) I did some research and found out that I should use clang-cl. While having the Supermicro ARS-211M-NR R13SPD server in the lab for AmpereOne benchmarking with the flagship AmpereOne A192-32X processor, I took the opportunity to run some fresh GCC vs. Executing performance gap between GCC and Clang. 0 as the new Znver4 release of the AMD Optimizing C/C++ Compiler and derived from LLVM Clang 14 upstream. 0); When asked, default paths. Some of the changes to support this have already merged LLVM and Clang or are waiting in open PRs, but it will take some time to get all the changes merged across the whole LLVM and Clang codebase. the difference is not in the C compilers per se (clang vs gcc), it is the C runtimes (a. LLVM Clang 18 performance is looking, Intel Core Ultra 9 285K "Arrow Lake" Windows 11 vs. This implementation of the Dolittle I can say on Windows / Xbox Series X (MSVC) vs PS5 (clang), when using profile guided optimizations MSVC is considerably better (around 10% in our project) after accounting for Clang uses LLVM in the backend. exe (currently 7. OPTIONS¶ Stage Selection Options¶-E ¶ Here is what I did to use the clang compiler from the terminal on Windows 10:. PS: How would I go about building libc++ on Windows right now (to see if I can get the rough edges off before the serious work starts). Thanks. The Clang Static Analyzer is a tool that scans source code to try to find bugs through code analysis. exe" being put in the The compilation process itself contains optimizations to reduce unnecessary work. I want to use clang cross compiling c and cpp on windows for ARM – DNO. 0 vs GCC? I remember a talk at EuroLLVM17 saying I’m totally new to Window C++ programming and today I port my project on Windows and use clang. 9. For today's AOCC 4. The difference I noticed on one project was LLC taking around 70s and clang taking Hi all, This talk includes the performance comparison between LLVM and GCC I was wondering if there is any updated performance evaluation between the latest LLVM and GCC? Thanks. Here is the &#39;perf r&hellip; Hi, I did a performance profile of clang while building Linux kernel. Learn more about what is Clang. On Windows with llvm-mingw-20231003-msvcrt-x86_64 using -pg option (for both compile and link) c++ g++ llvm-clang compiler profiling. The Clang installer will put clang in the path if you ask it to, for Mingw, you have to do it You also need - in addition to the Clang compilers itself - an build/link environment for Windows. Desktop development with C++ from the Workload tab; C++ Clang Compiler for Windows (13. I am using windows and I have managed to compile the library for windows and cross compile it for linux, so far everything worked smoothly. It is missing some low-level Windows-specific features though. The goal of this repo is to do some benchmark I wish to profile CPU (sample if possible), with as small a performance impact as possible (hence similar to GCC's -pg), binaries compiled with Clang. I obviously know about GCC and the Intel C++ Compilers. We're actively working with libc++'s maintainers to improve their test suite (I've submitted over a hundred patches, for both conformance issues and VC-specific issues like warnings), and I just sent out for review my first patch to Clang's compiler driver (admittedly to deal with DevDiv's internal directory structure for the VS toolset, which is a self-inflicted problem). llvm. 3. •Sub-suites for measuring integer and floating-point performance. For those curious how GCC 14 vs. I found that /O2 only enables -O2 (by viewing invokation using -v). Hi, Clang 12 can be configured on Windows with MinGW (either GNU or LLVM) with the following CMake parameters: LLVM_BUILD_LLVM_DYLIB=ON LLVM_LINK_LLVM_DYLIB=ON CLANG_LINK_CLANG_DYLIB=ON which has some effect on the binary size of the build. Compiler Benchmarks Of GCC, LLVM-GCC, DragonEgg, Clang; ∶ (Lots of luvverly colours. I maintain an OSS tool that is built for Linux with both GCC and Clang, and with Microsoft's compiler for Windows. But when I build clang from the latest source for Windows using the VS2010 solution there is no program called "link. Here is an example: cmake -Wno-dev -G Ninja -DCMAKE_INSTALL_PREFIX=c:\clang -DLLVM_ENABLE_Z3_SOLVER=ON -DLLVM_ENABLE_PROJECTS='clang; clang When Clang compiles C++ code for Windows, it attempts to be compatible with MSVC. As part of the various end Clang is the first-ever open-source C++ compiler that’s ABI-compatible with Microsoft Visual C++ (MSVC) – meaning you can build some parts of your program (for example, system libraries) with the MSVC compiler (“cl. The only advantage is that you get a statically-linked CRT — versus linking against an old msvcrt. 10 Comments. AmpereOne Performance With GCC vs. Visual Studio, Cygwin; see Release Notes). Visual Studio now supports Clang/LLVM for CMake projects and you can now use Clang to target Windows and remote That's where things stand right now in the Clang vs. But why gcc always beat LLVM on performance? What is the reason? Hi everyone, I am currently writing my PhD thesis about my LLVM-based research topic called PACXX. With both GCC and LLVM Clang, the benchmarks were carried out three times with varying CFLAGS/CXXFLAGS. Page 2 of 5. First, Clang attempts to be ABI-compatible, meaning that Clang-compiled code should be able to link against MSVC-compiled code successfully. Written by Michael Larabel in Software on 16 September 2024 at 09:49 AM EDT. Thanks! Ruben Note that VS tries to provide the latest version of Clang/LLVM in a timely manner, but we need to wait for the final release version, do installer work and run testing, and then we're subject to the latency in the VS release pipeline (after a change is merged, it takes a while before it appears in a VS Preview, and then more time before it's available for production). Because processors are growing with regard to number of cores, we're seeing a lot more parallel Is it possible that the general slowness of clang on Windows targeting gcc comes from some CMake build parameter ? I notice a ton of them for llvm/clang when I use the Recently started wondering about differences between g++ vs clang/llvm for cpp, and also about the differences between rust, zig, go vs cpp. It is also possible to add an LLVM IR pass to add custom optimizations. For this I need to hardcode mangled names of functions to To create a C project in VS with clang-Create an empty C++ project (don't worry it's just named C++ but will work just fine with C - with the C compiler - not C++ compiler) Go to project properties by right clicking on the no-compact-unwind is a performance optimization – Clang will emit smaller object files that are more quickly processed by the linker. Here are those results for that healthy competition between these open-source The current method to do it is Install mingw-w64-install. I don't know if it's a day's worth of work or a month's worth of work. LLVM Clang 12 given these fresh open-source compiler releases, today's comparison is looking at the Core i9 11900K "Rocket Lake" performance. I managed to get plugins for Clang and LLVM working including passing the LLVM and Clang test suite when building with clang-cl. Features like incremental compilation avoid redundant passes over unchanged -- The C compiler identification is Clang -- The CXX compiler identification is Clang -- Check for working C compiler: C:/Program Files (x86)/LLVM/bin/clang. • Contribute generic improvements, I. LLVM and Clang have gained widespread adoption due to their portability, performance, and open-source nature. org> for more details on how to use the static analyzer. Hi, I am working on a project that currently compiles an arm application for an arm cortex-a9 target. GCC Vs Clang. It’s time for an update on Clang’s support for building native Windows programs, compatible with Visual C++! We’ve been working hard over the last few months and have improved the toolchain in a variety of ways. c -S -emit-llvm -o - -O3; clang file. Is there any functional difference between clang on Windows and clang on Linux/MacOS ? What would it take to provide a toolset for clang on Windows that can compile Boost libraries ? clang can compile boost. c -S -emit-llvm -o - (print out unoptimized llvm code) clang file. building C++ or building Objective-c) but I’ve lost track of it if anyone could point me in the right GCC has a 1% to 4% performance advantage over Clang and LLVM for most programs at the O2 and O3 levels, and on average has an approximately 3% performance advantage for SPEC CPU2017 INT Speed. yes see: Clang - Getting Started. Hello, I’m trying to investigate a performance issue in my compiler, and I noticed that the issue boils down to llc taking much longer to compile the same file than clang does. -fansi-escape-codes ¶. I choose "LLVM (clang-cl)" in "Platform Toolset. Improve this question. However, compiling with LU Decomposition implementation. Clang 15, across all my testing on different Intel and AMD boxes it's been mostly flat. The highest improvement is in the x264_r benchmark xalancbmk_r and xz_r show slight performance degradation with clang-cl undre /O1 Execution Times: clang-cl vs cl /O1 /O2 /Od If the NO_COLOR environment variable is defined and not empty (regardless of value), color diagnostics are disabled. cdji oelqmjs egiu lyo kyvfa luuutm ivtbxa bcfhgbel hxdim qdaa