Editing LLVM (section)

{{Short description|Compiler backend for multiple programming languages}}
{{Infobox software
| name = LLVM
| logo = LLVM logo.png
| logo caption = The LLVM logo, a stylized [[wyvern]]<ref name="logo">{{Cite web |url=https://llvm.org/Logo.html |title=LLVM Logo |website=The LLVM Compiler Infrastructure Project}}</ref>
| author = [[Chris Lattner]], [[Vikram Adve]]
| developer = LLVM Developer Group
| released = {{start date and age|2003}}
| latest release version = {{wikidata|property|preferred|references|edit|Q223490|P348|P548=Q2804309}}
| latest release date = {{wikidata|qualifier|preferred|single|Q223490|P348|P548=Q2804309|P577}}
| latest preview version = {{wikidata|property|preferred|references|edit|Q223490|P348|P548=Q51930650}}
| latest preview date = {{wikidata|qualifier|preferred|single|Q223490|P348|P548=Q51930650|P577}}
| programming language = [[C++]]
| operating system = [[Cross-platform software|Cross-platform]]
| genre = [[Compiler]]
| license = [[Apache License 2.0]] with LLVM Exceptions (v9.0.0 or later)<ref name="License">{{cite web|url=https://releases.llvm.org/9.0.0/LICENSE.TXT|title=LICENSE.TXT|publisher=llvm.org|access-date=2019-09-24}}</ref><br>
Legacy license:<ref>{{Cite web |title=LLVM Developer Policy — LLVM 20.0.0git documentation |url=https://llvm.org/docs/DeveloperPolicy.html#legacy |access-date=2024-11-09 |website=llvm.org}}</ref><!-- "The last paragraph notwithstanding, the LLVM Project is in the middle of a large effort to change licenses .. Starting on 2024-06-01 (first of June 2024), new contributions only need to be covered by the new LLVM license, i.e. Apache-2.0 WITH LLVM-exception. Before this date, the project required all contributions to be made under both the new license and the legacy license. ..

A small portion of LLVM code remains exclusively covered by the legacy license. Contributions after 2024-06-01 are covered exclusively by the new license."--> [[University of Illinois/NCSA Open Source License|UIUC]] ([[BSD licenses|BSD-style]])
| website = {{URL|https://www.llvm.org}}
}}

'''LLVM''', also called LLVM Core, is a target-independent optimizer and code generator.<ref>{{Cite web| title = The LLVM Compiler Infrastructure Project| access-date = March 11, 2016| url = http://llvm.org/}}</ref> It can be used to develop a [[Compiler#Front end|frontend]] for any [[programming language]] and a [[Compiler#Back end|backend]] for any [[instruction set architecture]]. LLVM is designed around a [[language-independent specification|language-independent]] [[intermediate representation]] (IR) that serves as a [[Software portability|portable]], high-level [[assembly language]] that can be [[optimizing compiler|optimized]] with a variety of transformations over multiple passes.<ref name="langref">{{cite web|url=http://llvm.org/docs/LangRef.html|title=LLVM Language Reference Manual|access-date=June 9, 2019}}</ref> The name ''LLVM'' originally stood for ''Low Level Virtual Machine.'' However, the project has since expanded, and the name is no longer an acronym but an [[orphan initialism]].<ref>{{Cite web |title=The LLVM Compiler Infrastructure Project |url=https://llvm.org/|access-date=January 13, 2025 |website=llvm.org|archive-date=December 29, 2024 |archive-url=https://archive.today/20241229083604/https://llvm.org/}}</ref>

LLVM is written in [[C++]] and is designed for [[compile-time]], [[Linker (computing)|link-time]], [[runtime (program lifecycle phase)|runtime]], and "idle-time" optimization. Originally implemented for [[C (programming language)|C]] and C++, the language-agnostic design of LLVM has since spawned a wide variety of frontends: languages with compilers that use LLVM (or which do not directly use LLVM but can generate compiled programs as LLVM IR) include [[ActionScript]], [[Ada (programming language)|Ada]], [[C Sharp (programming language)|C#]] for [[.NET]],<ref>{{Cite web |title=Announcing LLILC - A new LLVM-based Compiler for .NET |url=https://dotnetfoundation.org/blog/2015/04/14/announcing-llilc-llvm-for-dotnet|access-date=2020-09-12 |website=dotnetfoundation.org|archive-date=December 12, 2021 |archive-url=https://web.archive.org/web/20211212184833/https://dotnetfoundation.org/blog/2015/04/14/announcing-llilc-llvm-for-dotnet |url-status=dead}}</ref><ref>{{cite web |url= http://www.mono-project.com/Mono_LLVM |title=Mono LLVM |access-date=March 10, 2013}}</ref><ref>{{cite book |last=Lattner |first=Chris |author-link=Chris Lattner |editor1-last=Brown |editor1-first=Amy |editor2-last=Wilson |editor2-first=Greg |year=2011 |title=The Architecture of Open Source Applications |url=http://www.aosabook.org/ |chapter=LLVM |chapter-url=http://www.aosabook.org/en/llvm.html}}</ref> [[Common Lisp]],<ref>{{cite web |title=Clasp |url=https://clasp-developers.github.io/ |publisher=Clasp Developers |access-date=2 December 2024}}</ref> [[PicoLisp]], [[Crystal (programming language)|Crystal]], [[CUDA]], [[D (programming language)|D]],<ref>{{cite web |title=LDC |url=https://wiki.dlang.org/LDC |website=D Wiki |access-date=2 December 2024}}</ref> [[Delphi (software)|Delphi]],<ref>{{cite web |title=LLVM-based Delphi Compilers |url=https://docwiki.embarcadero.com/RADStudio/Sydney/en/LLVM-based_Delphi_Compilers |publisher=Embarcadero |access-date=26 November 2024}}</ref> [[Dylan (programming language)|Dylan]], [[Forth (programming language)|Forth]],<ref>{{Cite web |url=https://github.com/reschivon/movForth |title=MovForth |website=[[GitHub]] |date=November 28, 2021}}</ref> [[Fortran]],<ref>{{cite web |title=The Flang Compiler |url=https://flang.llvm.org |publisher=LLVM Project |access-date=2 December 2024}}</ref> [[FreeBASIC]], [[Free Pascal]], [[Halide (programming language)|Halide]], [[Haskell]], [[Idris (programming language)|Idris]],<ref>{{Cite web |title=Rapid |url=https://rapid.sinyax.net/ |access-date=2024-11-22 |website=Rapid |language=en-gb}}</ref> [[Jai (programming language)|Jai]] (only for optimized release builds), [[Java bytecode]], [[Julia (programming language)|Julia]], [[Kotlin (programming language)|Kotlin]], [[LabVIEW]]'s G language,<ref>{{cite web|url=http://www.electronicdesign.com/test-measurement/what-s-difference-between-labview-2017-and-labview-nxg|title=What's the Difference Between LabVIEW 2017 and LabVIEW NXG?|author=William Wong|date=May 23, 2017|website=[[Electronic Design (magazine)|Electronic Design]]}}</ref><ref>{{cite web | url=https://www.ni.com/en/support/documentation/supplemental/10/ni-labview-compiler--under-the-hood.html | title=NI LabVIEW Compiler: Under the Hood }}</ref> [[Objective-C]], [[OpenCL]],<ref>{{cite news
 |last = Larabel |first = Michael
 |date = 11 April 2018
 |url = https://www.phoronix.com/scan.php?page=news_item&px=SPIRV-LLVM-Translator
 |title = Khronos Officially Announces Its LLVM/SPIR-V Translator
 |work = Phoronix.com
}}</ref> [[PostgreSQL]]'s SQL and PLpgSQL,<ref>{{Cite web|date=2020-11-12|title=32.1. What is JIT compilation?|url=https://www.postgresql.org/docs/11/jit-reason.html|access-date=2021-01-25 |website=PostgreSQL Documentation|language=en}}</ref> [[Ruby (programming language)|Ruby]],<ref>{{cite web|title=Features|url=http://www.rubymotion.com/tour/features/|website=RubyMotion|publisher=Scratchwork Development LLC|access-date=June 17, 2017|quote=[[RubyMotion]] transforms the Ruby source code of your project into ... machine code using a[n] ... ahead-of-time (AOT) compiler, based on LLVM.}}</ref> [[Rust (programming language)|Rust]],<ref>{{Cite web|url=https://rustc-dev-guide.rust-lang.org/backend/codegen.html|title=Code Generation - Guide to Rustc Development|website=rust-lang.org|access-date=2023-01-04}}</ref> [[Scala (programming language)|Scala]],<ref>{{Cite web|last=Reedy |first=Geoff |date=September 24, 2012 |title=Compiling Scala to LLVM |location=St. Louis, Missouri, United States |access-date=February 19, 2013 |url=http://www.infoq.com/presentations/Scala-LLVM}}</ref><ref>{{cite web |title=Scala Native |url=https://scala-native.org/ |access-date=26 November 2023}}</ref> [[Standard ML]],<ref>{{cite web |title=LLVMCodegen |url=http://mlton.org/LLVMCodegen |website=MLton |access-date=26 November 2024}}</ref> [[Swift (programming language)|Swift]], [[Xojo]], and [[Zig (programming language)|Zig]].