llvm/docs
Adrian Prantl 02474a32eb Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:55:02 +00:00
..
_static [docs] Update HTML pages to refer to CSS in a way that works locally and with Sphinx. 2012-04-19 20:20:34 +00:00
_templates [docs] Convert docs index page into Sphinx. 2012-04-19 16:31:37 +00:00
_themes/llvm-theme Sphinx CSS: remove negative letter-spacing, it makes some fonts look really 2012-09-30 20:43:24 +00:00
CommandGuide [LIT] Remove documentation for method since it does not exist 2014-08-21 18:52:58 +00:00
HistoricalNotes [typo] An LLVM. 2013-08-16 23:30:19 +00:00
TableGen Document !and. Fix !shl and friends -- they provide binary operations. 2014-09-03 13:17:03 +00:00
tutorial [docs] Clean up some more llvm-gcc stuff 2014-02-19 00:12:34 +00:00
AliasAnalysis.rst Update some AliasAnalysis pass docs for getAdjustedAnalysisPointer. 2014-05-22 19:38:25 +00:00
ARM-BE-bitcastfail.png [ARM64-BE] Add sphinx documentation for the ARM64 NEON implementation. 2014-05-12 15:13:39 +00:00
ARM-BE-bitcastsuccess.png [ARM64-BE] Add sphinx documentation for the ARM64 NEON implementation. 2014-05-12 15:13:39 +00:00
ARM-BE-ld1.png [ARM64-BE] Add sphinx documentation for the ARM64 NEON implementation. 2014-05-12 15:13:39 +00:00
ARM-BE-ldr.png [ARM64-BE] Add sphinx documentation for the ARM64 NEON implementation. 2014-05-12 15:13:39 +00:00
Atomics.rst [docs] Fixed a typo in Atomics.rst 2014-09-23 17:35:28 +00:00
BigEndianNEON.rst Fix typos 2014-05-15 01:52:21 +00:00
BitCodeFormat.rst Fix sphinx warning. 2014-09-18 21:54:02 +00:00
BlockFrequencyTerminology.rst Fix typos 2014-05-15 01:52:21 +00:00
BranchWeightMetadata.rst blockfreq: Document BlockFrequencyInfo terminology 2014-04-11 23:21:07 +00:00
Bugpoint.rst [docs] Fix up some links to the preferred style. 2014-04-08 21:06:22 +00:00
CMake.rst Introduce -DLLVM_USE_SANITIZER=Undefined CMake option to build UBSan-ified version of LLVM/Clang. 2014-08-29 00:50:36 +00:00
CMakeLists.txt Added Sphinx documentation generation to CMake build system. 2014-04-18 21:45:25 +00:00
CodeGenerator.rst [sphinx cleanup] 2014-09-10 20:43:03 +00:00
CodingStandards.rst CodingStandards: Document std::equal misbehaviour 2014-08-19 16:49:40 +00:00
CommandLine.rst Correct word hyphenations 2013-12-05 05:44:44 +00:00
CompilerWriterInfo.rst Fix some doc and comment typos 2014-04-09 14:47:27 +00:00
conf.py Update LLVM version: 3.5 => 3.6 2014-07-28 22:10:52 +00:00
CoverageMappingFormat.rst Docs: add documentation for the coverage mapping format. 2014-08-19 17:05:58 +00:00
DebuggingJITedCode.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
DeveloperPolicy.rst Document what backwards compatibility we provide for bitcode. 2014-07-23 22:43:22 +00:00
doxygen.cfg.in [docs] Teach CMake docs build how to generate Qt Creator help/documentation files. 2014-03-07 19:19:28 +00:00
doxygen.css [docs] Update Makefile for images removal. 2012-04-20 17:27:12 +00:00
doxygen.footer Update the copyright credits -- Happy new year 2014! 2014-01-01 08:27:31 +00:00
doxygen.header Tidy up. s/Low Level Virtual Machine/LLVM/. 2012-01-25 22:00:23 +00:00
doxygen.intro Tidy up. s/Low Level Virtual Machine/LLVM/. 2012-01-25 22:00:23 +00:00
Dummy.html Add a dummy documentation file to unbreak 'make install'. We need to find how 2012-12-13 13:37:35 +00:00
ExceptionHandling.rst Exception handling docs: Clarify how the llvm.eh.* intrinsics are used 2014-03-28 17:08:57 +00:00
ExtendedIntegerResults.txt
ExtendingLLVM.rst Fix documentation on the path to Bitcode reader/writer 2013-06-11 18:09:21 +00:00
Extensions.rst ARM: add VLA extension for WoA Itanium ABI 2014-06-09 20:18:42 +00:00
FAQ.rst remove an old entry whose link is broken anyway 2014-03-02 06:37:03 +00:00
GarbageCollection.rst Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
gcc-loops.png Update the gcc-loops benchmark 2013-01-20 07:01:04 +00:00
GetElementPtr.rst [docs] Clean up some more llvm-gcc stuff 2014-02-19 00:12:34 +00:00
GettingStarted.rst Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
GettingStartedVS.rst Document how to select build configuration with Visual C++ IDE or command line. 2014-06-05 16:42:26 +00:00
GoldPlugin.rst Update the LTO GoldPlugin documentation 2013-12-02 07:15:33 +00:00
HowToAddABuilder.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
HowToBuildOnARM.rst Adding some info about stability of ARM boards 2013-11-15 08:42:14 +00:00
HowToCrossCompileLLVM.rst [docs] Some typographical fixes. 2013-09-09 19:05:03 +00:00
HowToReleaseLLVM.rst docs: Update relaease documents to include the patch number in the RELEASE tags 2014-07-21 14:28:31 +00:00
HowToSetUpLLVMStyleRTTI.rst [C++11] Replace LLVM-style type traits with C++11 standard ones. 2014-03-07 14:42:25 +00:00
HowToSubmitABug.rst [docs] Nuke some references to llvm-gcc 2014-02-18 23:56:43 +00:00
HowToUseAttributes.rst Documentation: HowToUseAttributes: formatting (use monospaced font) 2013-02-12 18:26:08 +00:00
HowToUseInstrMappings.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
InAlloca.rst inalloca: *Really* fix the docs 2014-03-27 01:38:48 +00:00
index.rst fix a typo in doumentation index. 2014-09-26 06:59:15 +00:00
LangRef.rst [docs] Mention character array constants in docs/LangRef.rst 2014-09-11 12:02:59 +00:00
Lexicon.rst [docs] Document what "NFC" means in a commit message. 2014-09-06 00:19:16 +00:00
LinkTimeOptimization.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
linpack-pc.png Update the linpack benchmark with different array sizes. 2013-01-20 06:52:47 +00:00
LLVMBuild.rst [docs] Fix some links 2014-04-07 22:46:40 +00:00
LLVMBuild.txt LLVMBuild: Remove trailing newline, which irked me. 2011-12-12 19:48:00 +00:00
make.bat [docs] Stub out structure for Sphinx-based docs. 2012-04-19 16:31:19 +00:00
Makefile docs: Remove incompatibility with Solaris shell 2013-10-15 08:30:07 +00:00
Makefile.sphinx Revert "Treat warnings in Sphinx as errors. The reasons for doing this are..." 2014-07-22 18:09:17 +00:00
MakefileGuide.rst Remove projects/sample. 2014-03-12 22:40:22 +00:00
MarkedUpDisassembly.rst undo test commit (whitespace only) 2014-06-30 08:09:35 +00:00
MCJIT-creation.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJIT-dyld-load.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJIT-engine-builder.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJIT-load-object.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJIT-load.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJIT-resolve-relocations.png Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +00:00
MCJITDesignAndImplementation.rst Minor typo. 2014-09-05 04:56:43 +00:00
NVPTXUsage.rst Fix documentation typos 2013-12-20 00:33:39 +00:00
Packaging.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
Passes.rst docs: Remove documentation for legacy PGO options 2014-06-04 06:29:38 +00:00
Phabricator.rst Phabricator doc: Explicit the fact that the patch needs to be there before the commit 2014-07-04 09:00:35 +00:00
ProgrammersManual.rst Update my previous commit to fit 80 cols... 2014-09-25 10:58:16 +00:00
Projects.rst Remove projects/sample. 2014-03-12 22:40:22 +00:00
re_format.7
README.txt [docs] Add a note to docs/README.txt 2014-04-22 21:47:53 +00:00
ReleaseNotes.rst LTO: introduce object file-based on-disk module format. 2014-09-18 21:28:49 +00:00
ReleaseProcess.rst Update Release Process doc 2013-06-12 11:35:33 +00:00
SegmentedStacks.rst Move the segmented stack switch to a function attribute 2014-04-10 22:58:43 +00:00
SourceLevelDebugging.rst Move the complex address expression out of DIVariable and into an extra 2014-10-01 18:55:02 +00:00
SphinxQuickstartTemplate.rst [docs] Provide pointer for building Sphinx docs. 2013-02-27 18:33:21 +00:00
StackMaps.rst Stack map docs. Remove some stray markup. 2014-04-03 07:08:21 +00:00
SystemLibrary.rst remove the rest of the "written by" lines in the documentation. It is 2013-01-10 21:24:04 +00:00
TableGenFundamentals.rst Recover TableGen/LangRef, make it official 2014-04-01 09:51:49 +00:00
TestingGuide.rst Reduce verbiage of lit.local.cfg files 2014-06-09 22:42:55 +00:00
TestSuiteMakefileGuide.rst remove the rest of the "written by" lines in the documentation. It is 2013-01-10 21:24:04 +00:00
Vectorizers.rst Vectorization documentation for loop hint pragmas and Rpass diagnostics. 2014-06-27 18:30:08 +00:00
WritingAnLLVMBackend.rst [docs] Fix some links 2014-04-07 22:46:40 +00:00
WritingAnLLVMPass.rst docs: Remove documentation for legacy PGO options 2014-06-04 06:29:38 +00:00
yaml2obj.rst Object: rename ARMV7 to ARMNT 2014-03-11 03:08:37 +00:00
YamlIO.rst [YAML] Add an optional argument EnumMask to the yaml::IO::bitSetCase(). 2014-05-23 08:07:09 +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 docs/
    make -f Makefile.sphinx
    $BROWSER _build/html/index.html

The mapping between reStructuredText files and generated documentation is
`docs/Foo.rst` <-> `_build/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/man/`.

    cd docs/
    make -f Makefile.sphinx man
    man -l _build/man/FileCheck.1

The correspondence between .rst files and man pages is
`docs/CommandGuide/Foo.rst` <-> `_build/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 reachibility of external links in the documentation can be checked by
running:

    cd docs/
    make -f Makefile.sphinx linkcheck