llvm/docs
Hiroshi Yamauchi dd33e177dd Irreducible loop metadata for more accurate block frequency under PGO.
Summary:
Currently the block frequency analysis is an approximation for irreducible
loops.

The new irreducible loop metadata is used to annotate the irreducible loop
headers with their header weights based on the PGO profile (currently this is
approximated to be evenly weighted) and to help improve the accuracy of the
block frequency analysis for irreducible loops.

This patch is a basic support for this.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: mehdi_amini, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D39028

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317278 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-02 22:26:51 +00:00
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_ocamldoc [OCaml] Use a nicer style for documentation than OCaml default. 2015-07-17 06:37:59 +00:00
_static Fix some typos in the doc 2016-08-28 20:29:18 +00:00
_templates
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CommandGuide [dsymutil][doc] Improve wording in manpage and rename file. 2017-11-02 18:44:54 +00:00
Frontend [docs][PerformanceTips] Add text on allocas and alignment 2015-09-10 17:03:10 +00:00
HistoricalNotes
PDB Add documentation for the PDB Module Info stream. 2016-11-29 22:14:56 +00:00
Proposals fix various typos 2017-06-26 02:45:39 +00:00
TableGen Improvements to TableGen/LangIntro.rst 2017-05-02 13:47:10 +00:00
tutorial [ORC][Kaleidoscope] Update ORCJit tutorial. 2017-09-17 00:24:43 +00:00
AdvancedBuilds.rst Fixing autocorrect changing cmake->make 2016-03-18 22:11:51 +00:00
AliasAnalysis.rst [docs] AliasAnalysis: clarify that PartialAlias doesn't enforce 2017-07-15 09:09:24 +00:00
AMDGPUUsage.rst [AMDGPU] Emit metadata for hidden arguments for kernel enqueue 2017-10-30 14:30:28 +00:00
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Atomics.rst fix some various typos in the doc 2016-07-02 19:28:40 +00:00
Benchmarking.rst Add some tips on benchmarking. 2017-05-24 16:39:12 +00:00
BigEndianNEON.rst
BitCodeFormat.rst Represent runtime preemption in the IR. 2017-10-26 15:00:26 +00:00
BlockFrequencyTerminology.rst
BranchWeightMetadata.rst [Doc] Document prof metadata in LangRef 2017-06-15 15:57:12 +00:00
Bugpoint.rst Correct 'teh' and other typos / repeated words. 2015-04-14 20:52:58 +00:00
CFIVerify.rst Introduce the llvm-cfi-verify tool (resubmission of D37937). 2017-09-20 20:38:14 +00:00
CMake.rst [tools] Add option to install binutils symlinks 2017-11-02 21:43:32 +00:00
CMakeLists.txt [dsymutil][doc] Improve wording in manpage and rename file. 2017-11-02 18:44:54 +00:00
CMakePrimer.rst [docs] In the CMake primer, correct the description of the ARGV/ARGN variables. 2017-08-24 05:38:39 +00:00
CodeGenerator.rst Add documentation for various aspects of the AMDGPU backend. 2017-06-06 20:31:59 +00:00
CodeOfConduct.rst [Conduct] Refine what "rare cases" means wrt violations outside our spaces. 2016-07-06 19:32:41 +00:00
CodingStandards.rst [docs] Add a note on iteration of unordered containers to coding standards 2017-09-06 20:19:10 +00:00
CommandLine.rst Remove references to response file argument in CommandLine.rst 2017-09-20 22:41:34 +00:00
CompileCudaWithLLVM.rst [Docs] Update docs to indicate that CUDA compilation is supported on Windows. 2017-01-05 16:54:28 +00:00
CompilerWriterInfo.rst Fix broken links to the Itanium CXX ABI 2017-09-12 00:19:11 +00:00
conf.py Update trunk version to 6.0.0svn 2017-07-19 12:19:01 +00:00
Coroutines.rst fix trivial typos in documents; NFC 2017-07-02 12:44:27 +00:00
CoverageMappingFormat.rst [Coverage] Use gap regions to select better line exec counts 2017-09-18 23:37:28 +00:00
DebuggingJITedCode.rst
DeveloperPolicy.rst Fixed broken links in docs. 2017-09-22 21:10:37 +00:00
Docker.rst Made a script to build docker images easier to use. 2017-07-06 12:46:51 +00:00
doxygen-mainpage.dox [docs] Updated docs to work with Doxygen 1.8.11 2016-03-06 03:50:08 +00:00
doxygen.cfg.in Sync with changes from r300825 in clang. 2017-04-27 17:23:53 +00:00
ExceptionHandling.rst Fix broken links to the Itanium CXX ABI 2017-09-12 00:19:11 +00:00
ExtendedIntegerResults.txt
ExtendingLLVM.rst [WinEH] Add llvm.eh.exceptionpointer intrinsic 2015-09-03 09:15:32 +00:00
Extensions.rst Change section flag character for SHF_LINK_ORDER to "o". 2017-04-04 22:35:08 +00:00
FAQ.rst fix some typos in the doc 2016-07-28 09:28:58 +00:00
FaultMaps.rst Fix the docs build 2017-02-07 20:36:03 +00:00
FuzzingLLVM.rst [llvm-demangle-fuzzer] Add a fuzz target for ItaniumDemangler. 2017-10-13 17:35:37 +00:00
GarbageCollection.rst Tidy up example of getting the pointer size. 2016-10-14 05:45:46 +00:00
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GetElementPtr.rst [docs] change a few code-blocks to llvm from text 2017-07-26 14:11:23 +00:00
GettingStarted.rst Added instructions for obtaining clang-tools-extra to the Getting Started page. 2017-10-24 17:28:39 +00:00
GettingStartedVS.rst Update the documentation and CMake file for Visual Studio generators. 2017-05-25 21:01:30 +00:00
GlobalISel.rst [globalisel] Add very brief docs summarizing the ISel part of the LLVMDev tutorial. 2017-10-23 17:18:44 +00:00
GoldPlugin.rst [docs] As of binutils 2.21.51.0.2, ld.bfd supports plugins too, represent this in docs 2017-06-23 13:54:10 +00:00
HowToAddABuilder.rst Added more info on silent master to the doc. 2017-07-05 20:45:44 +00:00
HowToBuildOnARM.rst [Docs] Change ARM build info to CMake 2015-11-06 18:39:34 +00:00
HowToCrossCompileLLVM.rst [docs] Fix unexpected indentation in HowToCrossCompileLLVM.rst 2016-05-10 14:02:46 +00:00
HowToReleaseLLVM.rst docs: Fix formatting in HowToReleaseLLVM 2017-09-19 03:27:26 +00:00
HowToSetUpLLVMStyleRTTI.rst [docs][LLVM-style RTTI] Add a mention of multiple inheritance. 2015-02-07 01:16:26 +00:00
HowToSubmitABug.rst Update Bugzilla URLs in docs 2017-02-17 08:26:11 +00:00
HowToUseAttributes.rst Fix RST docs AttributeList heading underline 2017-03-21 17:05:00 +00:00
HowToUseInstrMappings.rst [docs] Fixing Sphinx warnings to unclog the buildbot 2016-07-20 12:16:38 +00:00
InAlloca.rst [docs] Fixing Sphinx warnings to unclog the buildbot 2016-07-20 12:16:38 +00:00
index.rst docs: Add some information about Fuzzing LLVM itself 2017-10-12 01:44:24 +00:00
LangRef.rst Irreducible loop metadata for more accurate block frequency under PGO. 2017-11-02 22:26:51 +00:00
Lexicon.rst [Lexicon] Add "GEP" 2017-08-18 15:35:53 +00:00
LibFuzzer.rst docs: Add some information about Fuzzing LLVM itself 2017-10-12 01:44:24 +00:00
LinkTimeOptimization.rst [docs] Typos and whitespace fixed in LTO docs. 2016-11-29 18:00:31 +00:00
linpack-pc.png
LLVMBuild.rst Fix LLVMBuild.txt typo. NFC 2017-04-03 18:21:50 +00:00
LLVMBuild.txt
make.bat
Makefile.sphinx Bring back Makefile.sphinx 2016-03-23 00:30:57 +00:00
MarkedUpDisassembly.rst [docs] Fixing Sphinx warnings to unclog the buildbot 2016-07-20 12:16:38 +00:00
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MCJITDesignAndImplementation.rst Fix several accidental DOS line endings in source files 2016-01-03 17:22:03 +00:00
MemorySSA.rst Fix some typos in the doc 2016-08-28 20:29:18 +00:00
MergeFunctions.rst [docs] Fixing Sphinx warnings to unclog the buildbot 2016-07-20 12:16:38 +00:00
MIRLangRef.rst MIParser/MIRPrinter: Compute block successors if not explicitely specified 2017-05-05 21:09:30 +00:00
NVPTXUsage.rst Update NVVMReflect usage doc to new idiom for adding target-specific early passes. 2017-01-27 19:44:24 +00:00
OptBisect.rst Remove opt-bisect support for "cases" in favor of debug counters 2017-03-11 01:41:03 +00:00
Packaging.rst
Passes.rst Remove the ScalarReplAggregates pass 2016-06-15 00:19:09 +00:00
Phabricator.rst docs/Phabricator: Better git examples to produce full context patches 2017-06-15 22:09:30 +00:00
ProgrammersManual.rst [docs] Code example fix 2017-10-24 10:23:10 +00:00
Projects.rst Rename all references to old mailing lists to new lists.llvm.org address. 2015-08-05 03:51:17 +00:00
re_format.7
README.txt Remove test commit change. 2017-06-24 20:13:32 +00:00
ReleaseNotes.rst Add a ReleaseNotes blurb for Execute.*Wait API change 2017-09-15 11:45:30 +00:00
ReleaseProcess.rst [OPENMP] Make -fopenmp to turn on OpenMP support by default. 2015-12-10 05:45:58 +00:00
ReportingGuide.rst fix some various typos in the doc 2016-07-02 19:28:40 +00:00
ScudoHardenedAllocator.rst [docs] Fix Scudo documentation error 2017-08-29 19:54:19 +00:00
SegmentedStacks.rst [docs] Fixing Sphinx warnings to unclog the buildbot 2016-07-20 12:16:38 +00:00
SourceLevelDebugging.rst [docs] Fix a small typo 2017-10-26 17:58:05 +00:00
SphinxQuickstartTemplate.rst
StackMaps.rst [StackMaps] Increase the size of the "location size" field 2017-04-28 04:48:42 +00:00
Statepoints.rst [docs] change a few code-blocks to llvm from text 2017-07-26 14:11:23 +00:00
SystemLibrary.rst
TableGenFundamentals.rst
TestingGuide.rst Revert "lit.py: Add new %{shared_output(LABEL)} substitution" 2017-10-14 04:01:27 +00:00
TestSuiteMakefileGuide.rst Fix the docs I broke 2016-03-11 23:31:02 +00:00
TypeMetadata.rst Fixed broken links in docs. 2017-09-22 21:10:37 +00:00
Vectorizers.rst [docs] Update name of vectorization interleave flag. 2017-05-31 23:02:55 +00:00
WritingAnLLVMBackend.rst [docs] Document how to debug instruction scheduling model generation 2017-07-19 14:10:42 +00:00
WritingAnLLVMPass.rst [docs] Make WritingAnLLVMPass.rst up-to-date with current state of things 2016-09-27 12:07:21 +00:00
XRay.rst [XRay] [docs] Document how to generate flamegraphs from xray traces. 2017-10-19 22:35:09 +00:00
XRayExample.rst [XRay] [docs] Document how to generate flamegraphs from xray traces. 2017-10-19 22:35:09 +00:00
XRayFDRFormat.rst [XRay][tools] Support tail-call exits before we write them in the runtime 2017-09-18 06:08:46 +00:00
yaml2obj.rst Summary: 2015-07-28 16:18:17 +00:00
YamlIO.rst fix some typos in the doc 2017-01-14 11:37:01 +00:00

LLVM Documentation
==================

LLVM's documentation is written in reStructuredText, a lightweight
plaintext markup language (file extension `.rst`). While the
reStructuredText documentation should be quite readable in source form, it
is mostly meant to be processed by the Sphinx documentation generation
system to create HTML pages which are hosted on <http://llvm.org/docs/> and
updated after every commit. Manpage output is also supported, see below.

If you instead would like to generate and view the HTML locally, install
Sphinx <http://sphinx-doc.org/> and then do:

    cd <build-dir>
    cmake -DLLVM_ENABLE_SPHINX=true -DSPHINX_OUTPUT_HTML=true <src-dir>
    make -j3 docs-llvm-html
    $BROWSER <build-dir>/docs//html/index.html

The mapping between reStructuredText files and generated documentation is
`docs/Foo.rst` <-> `<build-dir>/docs//html/Foo.html` <-> `http://llvm.org/docs/Foo.html`.

If you are interested in writing new documentation, you will want to read
`SphinxQuickstartTemplate.rst` which will get you writing documentation
very fast and includes examples of the most important reStructuredText
markup syntax.

Manpage Output
===============

Building the manpages is similar to building the HTML documentation. The
primary difference is to use the `man` makefile target, instead of the
default (which is `html`). Sphinx then produces the man pages in the
directory `<build-dir>/docs/man/`.

    cd <build-dir>
    cmake -DLLVM_ENABLE_SPHINX=true -DSPHINX_OUTPUT_MAN=true <src-dir>
    make -j3 docs-llvm-man
    man -l >build-dir>/docs/man/FileCheck.1

The correspondence between .rst files and man pages is
`docs/CommandGuide/Foo.rst` <-> `<build-dir>/docs//man/Foo.1`.
These .rst files are also included during HTML generation so they are also
viewable online (as noted above) at e.g.
`http://llvm.org/docs/CommandGuide/Foo.html`.

Checking links
==============

The reachability of external links in the documentation can be checked by
running:

    cd docs/
    make -f Makefile.sphinx linkcheck

Doxygen page Output
==============

Install doxygen <http://www.stack.nl/~dimitri/doxygen/download.html> and dot2tex <https://dot2tex.readthedocs.io/en/latest>.

    cd <build-dir>
    cmake -DLLVM_ENABLE_DOXYGEN=On <llvm-top-src-dir>
    make doxygen-llvm # for LLVM docs
    make doxygen-clang # for clang docs

It will generate html in
    
    <build-dir>/docs/doxygen/html # for LLVM docs
    <build-dir>/tools/clang/docs/doxygen/html # for clang docs