llvm-project/llvm/docs
Peter Collingbourne 21521891a2 IR: Allow metadata attachments on declarations, and fix lazy loaded metadata issue with globals.
This change is motivated by an upcoming change to the metadata representation
used for CFI. The indirect function call checker needs type information for
external function declarations in order to correctly generate jump table
entries for such declarations. We currently associate such type information
with declarations using a global metadata node, but I plan [1] to move all
such metadata to global object attachments.

In bitcode, metadata attachments for function declarations appear in the
global metadata block. This seems reasonable to me because I expect metadata
attachments on declarations to be uncommon. In the long term I'd also expect
this to be the case for CFI, because we'd want to use some specialized bitcode
format for this metadata that could be read as part of the ThinLTO thin-link
phase, which would mean that it would not appear in the global metadata block.

To solve the lazy loaded metadata issue I was seeing with D20147, I use the
same bitcode representation for metadata attachments for global variables as I
do for function declarations. Since there's a use case for metadata attachments
in the global metadata block, we might as well use that representation for
global variables as well, at least until we have a mechanism for lazy loading
global variables.

In the assembly format, the metadata attachments appear after the "declare"
keyword in order to avoid a parsing ambiguity.

[1] http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21052

llvm-svn: 273336
2016-06-21 23:42:48 +00:00
..
CommandGuide [FileCheck] Document --check-prefixes. 2016-06-14 16:42:05 +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
_ocamldoc [OCaml] Use a nicer style for documentation than OCaml default. 2015-07-17 06:37:59 +00:00
_static
_templates
_themes/llvm-theme
tutorial [Kaleidoscope][BuildingAJIT] Remove some superfluous commas in Chapter 2. 2016-06-20 18:37:52 +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
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
Atomics.rst Remove the ScalarReplAggregates pass 2016-06-15 00:19:09 +00:00
BigEndianNEON.rst
BitCodeFormat.rst IR: Allow metadata attachments on declarations, and fix lazy loaded metadata issue with globals. 2016-06-21 23:42:48 +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 Correct 'teh' and other typos / repeated words. 2015-04-14 20:52:58 +00:00
CMake.rst Try to fix docs build after rL271440 2016-06-02 00:26:18 +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
CMakePrimer.rst [Docs] Add CMake Primer document 2016-04-29 20:34:54 +00:00
CodeGenerator.rst [docs] Update AMDGPU relocation information 2016-06-14 17:20:29 +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 [CUDA] Add section to docs about controlling fp optimizations. 2016-05-25 23:11:31 +00:00
CompilerWriterInfo.rst Update psabi link for x86-64. Add link to linux gabi supplement. 2016-04-12 21:54:57 +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 Most common problem is that I get md5 hashes, not crypt hashes. 2016-05-11 03:47:36 +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 Use a comma after the unique keyword. 2015-04-06 16:34:41 +00:00
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 Document the CoreCLR GC Strategy 2015-05-21 00:50:10 +00:00
GetElementPtr.rst Update LangRef for getelementptr explicit type changes 2015-03-04 22:02:58 +00:00
GettingStarted.rst [CMake] Update to requiring CMake 3.4.3 2016-05-31 20:21:32 +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 [docs] Fix unexpected indentation in HowToCrossCompileLLVM.rst 2016-05-10 14:02:46 +00:00
HowToReleaseLLVM.rst Fix some typos in the llvm doc 2016-02-14 20:16:22 +00:00
HowToSetUpLLVMStyleRTTI.rst [docs][LLVM-style RTTI] Add a mention of multiple inheritance. 2015-02-07 01:16:26 +00:00
HowToSubmitABug.rst
HowToUseAttributes.rst
HowToUseInstrMappings.rst
InAlloca.rst
LLVMBuild.rst Fixing the documentation builds 2016-01-26 22:53:12 +00:00
LLVMBuild.txt
LangRef.rst LangRef: Note expectations when loading with extra alignment 2016-06-16 16:33:41 +00:00
Lexicon.rst [docs] Document "LGTM" in the lexicon. 2015-06-04 20:28:09 +00:00
LibFuzzer.rst [libFuzzer] docs: merge two lines with cmake instructions, add -DLLVM_ENABLE_ASSERTIONS=ON 2016-06-08 01:31:40 +00:00
LinkTimeOptimization.rst Fix a typo in the documentation of LTO 2014-12-03 07:32:36 +00:00
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
MIRLangRef.rst MIRLangRef: Add documentation for the subregister indices. 2015-09-08 11:39:47 +00:00
Makefile.sphinx Bring back Makefile.sphinx 2016-03-23 00:30:57 +00:00
MarkedUpDisassembly.rst
MergeFunctions.rst Fix some typos in the llvm doc 2016-02-14 20:16:22 +00:00
NVPTXUsage.rst [NVPTX:doc] Update code examples to conform to the latest IR. 2016-05-04 17:34:57 +00:00
Packaging.rst
Passes.rst Remove the ScalarReplAggregates pass 2016-06-15 00:19:09 +00:00
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
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 Fix list of deprecated C API attribute functions 2016-06-14 22:23:29 +00:00
ReleaseProcess.rst [OPENMP] Make -fopenmp to turn on OpenMP support by default. 2015-12-10 05:45:58 +00:00
ScudoHardenedAllocator.rst [sanitizer] Initial implementation of a Hardened Allocator 2016-06-07 01:20:26 +00:00
SegmentedStacks.rst
SourceLevelDebugging.rst Add info to SourceLevelDebugging about CodeView 2016-06-07 20:27:30 +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
TestSuiteMakefileGuide.rst Fix the docs I broke 2016-03-11 23:31:02 +00:00
TestingGuide.rst [Docs] Add some requirements to the Testing Guide 2016-05-14 14:27:40 +00:00
Vectorizers.rst Correct 'teh' and other typos / repeated words. 2015-04-14 20:52:58 +00:00
WritingAnLLVMBackend.rst [Docs][WritingAnLLVMBackend] Makefiles are deprecated 2016-05-26 21:31:56 +00:00
WritingAnLLVMPass.rst Fix typo. 2016-03-06 12:37:34 +00:00
YamlIO.rst [docs] Fix typo in YamlIO.rst 2016-02-04 20:42:43 +00:00
conf.py Update version to 3.9. 2016-01-13 17:32:32 +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
gcc-loops.png
index.rst [docs] fix the build by including ScudoHardenedAllocator into toc; mention SourceBasedCodeCoverage.html in libFuzzer docs 2016-06-07 23:13:54 +00:00
linpack-pc.png
make.bat
re_format.7
yaml2obj.rst Summary: 2015-07-28 16:18:17 +00:00

README.txt

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