llvm/docs
Adam Nemet 8d171c8f85 [LoopDist] Add llvm.loop.distribute.enable loop metadata
Summary:
D19403 adds a new pragma for loop distribution.  This change adds
support for the corresponding metadata that the pragma is translated to
by the FE.

As part of this I had to rethink the flag -enable-loop-distribute.  My
goal was to be backward compatible with the existing behavior:

  A1. pass is off by default from the optimization pipeline
  unless -enable-loop-distribute is specified

  A2. pass is on when invoked directly from opt (e.g. for unit-testing)

The new pragma/metadata overrides these defaults so the new behavior is:

  B1. A1 + enable distribution for individual loop with the pragma/metadata

  B2. A2 + disable distribution for individual loop with the pragma/metadata

The default value whether the pass is on or off comes from the initiator
of the pass.  From the PassManagerBuilder the default is off, from opt
it's on.

I moved -enable-loop-distribute under the pass.  If the flag is
specified it overrides the default from above.

Then the pragma/metadata can further modifies this per loop.

As a side-effect, we can now also use -enable-loop-distribute=0 from opt
to emulate the default from the optimization pipeline.  So to be precise
this is the new behavior:

  C1. pass is off by default from the optimization pipeline
  unless -enable-loop-distribute or the pragma/metadata enables it

  C2. pass is on when invoked directly from opt
  unless -enable-loop-distribute=0 or the pragma/metadata disables it

Reviewers: hfinkel

Subscribers: joker.eph, mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D19431

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267672 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-27 05:28:18 +00:00
..
_ocamldoc [OCaml] Use a nicer style for documentation than OCaml default. 2015-07-17 06:37:59 +00:00
_static
_templates
_themes/llvm-theme
CommandGuide Document standard substitutions defined by lit. 2016-04-04 17:14:45 +00:00
Frontend [docs][PerformanceTips] Add text on allocas and alignment 2015-09-10 17:03:10 +00:00
HistoricalNotes
TableGen Rename all references to old mailing lists to new lists.llvm.org address. 2015-08-05 03:51:17 +00:00
tutorial Remove every uses of getGlobalContext() in LLVM (but the C API) 2016-04-14 21:59:01 +00:00
AdvancedBuilds.rst Fixing autocorrect changing cmake->make 2016-03-18 22:11:51 +00:00
AliasAnalysis.rst fix typo 2016-01-13 16:46:41 +00:00
AMDGPUUsage.rst AMDGPU: Document address space mapping 2016-04-06 01:29:19 +00:00
ARM-BE-bitcastfail.png
ARM-BE-bitcastsuccess.png
ARM-BE-ld1.png
ARM-BE-ldr.png
Atomics.rst Add __atomic_* lowering to AtomicExpandPass. 2016-04-12 20:18:48 +00:00
BigEndianNEON.rst
BitCodeFormat.rst Swift Calling Convention: add swiftcc. 2016-04-05 22:41:47 +00:00
BitSets.rst docs: Document how bitsets may be used to encode type information. 2016-02-03 02:01:08 +00:00
BlockFrequencyTerminology.rst
BranchWeightMetadata.rst Fix typos. 2015-09-12 01:17:08 +00:00
Bugpoint.rst
CMake.rst [Docs] Updating CMake docs to include LLVM_OPTIMIZED_TABLEGEN 2016-03-24 18:46:43 +00:00
CMakeLists.txt Doxygen: add build option to use svg instead of png files for graphs 2015-08-17 23:24:17 +00:00
CodeGenerator.rst [docs] "Straightforward" is one word. 2016-03-14 20:18:51 +00:00
CodingStandards.rst Disable Visual C++ 2013 Debug mode assert on null pointer in some STL algorithms, 2015-08-21 17:31:03 +00:00
CommandLine.rst Add missing underlines for a docs section. NFC 2015-07-24 00:29:50 +00:00
CompileCudaWithLLVM.rst [docs] Add gpucc publication and tutorial. 2016-03-30 05:05:40 +00:00
CompilerWriterInfo.rst Update psabi link for x86-64. Add link to linux gabi supplement. 2016-04-12 21:54:57 +00:00
conf.py Update version to 3.9. 2016-01-13 17:32:32 +00:00
CoverageMappingFormat.rst [docs] Corrections w.r.t V2 of the coverage mapping format 2016-03-28 22:16:01 +00:00
DebuggingJITedCode.rst
DeveloperPolicy.rst Point link to CODE_OWNERS.txt to klaus instead of viewvc. 2016-04-22 17:41:12 +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 [docs] Updated docs to work with Doxygen 1.8.11 2016-03-06 03:50:08 +00:00
Dummy.html
ExceptionHandling.rst [WinEH] Disallow cyclic unwinds 2016-01-10 04:31:05 +00:00
ExtendedIntegerResults.txt
ExtendingLLVM.rst [WinEH] Add llvm.eh.exceptionpointer intrinsic 2015-09-03 09:15:32 +00:00
Extensions.rst
FAQ.rst FAQ: Remove the entire Build Problems section 2016-03-23 06:54:42 +00:00
FaultMaps.rst [FaultMaps] Let the frontend pre-select implicit null check candidates. 2015-06-30 21:22:32 +00:00
GarbageCollection.rst
gcc-loops.png
GetElementPtr.rst
GettingStarted.rst docs: Fix footnote after r260042. 2016-03-28 21:24:46 +00:00
GettingStartedVS.rst Clarifying some of the requirements for building with Visual Studio on Windows. Namely, we require the latest Update to be installed (for sanity purposes), and we require CMake 2.8.12.2 for building LLVM with Visual Studio. 2016-03-29 20:23:55 +00:00
GoldPlugin.rst [docs] Remove references to autotools build. 2016-01-30 01:10:15 +00:00
HowToAddABuilder.rst
HowToBuildOnARM.rst [Docs] Change ARM build info to CMake 2015-11-06 18:39:34 +00:00
HowToCrossCompileLLVM.rst
HowToReleaseLLVM.rst Fix some typos in the llvm doc 2016-02-14 20:16:22 +00:00
HowToSetUpLLVMStyleRTTI.rst
HowToSubmitABug.rst
HowToUseAttributes.rst
HowToUseInstrMappings.rst
InAlloca.rst
index.rst Updates based on post-commit review of r263834 2016-03-18 21:57:51 +00:00
LangRef.rst [LoopDist] Add llvm.loop.distribute.enable loop metadata 2016-04-27 05:28:18 +00:00
Lexicon.rst
LibFuzzer.rst [libFuzzer] more trophies 2016-04-19 22:37:44 +00:00
LinkTimeOptimization.rst
linpack-pc.png
LLVMBuild.rst Fixing the documentation builds 2016-01-26 22:53:12 +00:00
LLVMBuild.txt
make.bat
Makefile.sphinx Bring back Makefile.sphinx 2016-03-23 00:30:57 +00:00
MarkedUpDisassembly.rst
MCJIT-creation.png
MCJIT-dyld-load.png
MCJIT-engine-builder.png
MCJIT-load-object.png
MCJIT-load.png
MCJIT-resolve-relocations.png
MCJITDesignAndImplementation.rst Fix several accidental DOS line endings in source files 2016-01-03 17:22:03 +00:00
MergeFunctions.rst Fix some typos in the llvm doc 2016-02-14 20:16:22 +00:00
MIRLangRef.rst MIRLangRef: Add documentation for the subregister indices. 2015-09-08 11:39:47 +00:00
NVPTXUsage.rst [NVPTX] Make NVVMReflect a function pass. 2016-03-30 20:40:11 +00:00
Packaging.rst
Passes.rst
Phabricator.rst [docs] Improve the documentation on committing code reviewed on 2016-01-14 13:39:29 +00:00
ProgrammersManual.rst Remove every uses of getGlobalContext() in LLVM (but the C API) 2016-04-14 21:59:01 +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 [docs] Update the docs to describe how to build the docs with cmake 2016-02-07 15:42:12 +00:00
ReleaseNotes.rst [ppc64] Reenable sibling call optimization on ppc64 since fixed tsan library tail-call issue 2016-04-26 07:38:24 +00:00
ReleaseProcess.rst [OPENMP] Make -fopenmp to turn on OpenMP support by default. 2015-12-10 05:45:58 +00:00
SegmentedStacks.rst
SourceLevelDebugging.rst testcase gardening: update the emissionKind enum to the new syntax. (NFC) 2016-04-01 00:16:49 +00:00
SphinxQuickstartTemplate.rst
StackMaps.rst List supported architectures for StackMap section and related intrinsics 2015-07-16 21:10:46 +00:00
Statepoints.rst [Statepoint docs] Delete trailing whitespace 2016-03-04 18:14:09 +00:00
SystemLibrary.rst
TableGenFundamentals.rst
TestingGuide.rst Fixing the documentation builds 2016-01-26 22:53:12 +00:00
TestSuiteMakefileGuide.rst Fix the docs I broke 2016-03-11 23:31:02 +00:00
Vectorizers.rst
WritingAnLLVMBackend.rst
WritingAnLLVMPass.rst Fix typo. 2016-03-06 12:37:34 +00:00
yaml2obj.rst Summary: 2015-07-28 16:18:17 +00:00
YamlIO.rst [docs] Fix typo in YamlIO.rst 2016-02-04 20:42:43 +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