1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 03:33:20 +01:00
llvm-mirror/docs
Michael J. Spencer eeeb060307 [IR] Make {extract,insert}element accept an index of any integer type.
Given the following C code llvm currently generates suboptimal code for
x86-64:

__m128 bss4( const __m128 *ptr, size_t i, size_t j )
{
    float f = ptr[i][j];
    return (__m128) { f, f, f, f };
}

=================================================

define <4 x float> @_Z4bss4PKDv4_fmm(<4 x float>* nocapture readonly %ptr, i64 %i, i64 %j) #0 {
  %a1 = getelementptr inbounds <4 x float>* %ptr, i64 %i
  %a2 = load <4 x float>* %a1, align 16, !tbaa !1
  %a3 = trunc i64 %j to i32
  %a4 = extractelement <4 x float> %a2, i32 %a3
  %a5 = insertelement <4 x float> undef, float %a4, i32 0
  %a6 = insertelement <4 x float> %a5, float %a4, i32 1
  %a7 = insertelement <4 x float> %a6, float %a4, i32 2
  %a8 = insertelement <4 x float> %a7, float %a4, i32 3
  ret <4 x float> %a8
}

=================================================

        shlq    $4, %rsi
        addq    %rdi, %rsi
        movslq  %edx, %rax
        vbroadcastss    (%rsi,%rax,4), %xmm0
        retq

=================================================

The movslq is uneeded, but is present because of the trunc to i32 and then
sext back to i64 that the backend adds for vbroadcastss.

We can't remove it because it changes the meaning. The IR that clang
generates is already suboptimal. What clang really should emit is:

  %a4 = extractelement <4 x float> %a2, i64 %j

This patch makes that legal. A separate patch will teach clang to do it.

Differential Revision: http://reviews.llvm.org/D3519

llvm-svn: 207801
2014-05-01 22:12:39 +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 [docs] Fix some links 2014-04-07 22:46:40 +00:00
HistoricalNotes [typo] An LLVM. 2013-08-16 23:30:19 +00:00
TableGen [docs] VCS contains a record of authorship 2014-04-08 21:12:56 +00:00
tutorial [docs] Clean up some more llvm-gcc stuff 2014-02-19 00:12:34 +00:00
AliasAnalysis.rst [docs] Fix up some links to the preferred style. 2014-04-08 21:06:22 +00:00
Atomics.rst Small correction to unordered memory code generation of ARM LDRD 2013-06-18 23:07:16 +00:00
BitCodeFormat.rst Remove the linker_private and linker_private_weak linkages. 2014-03-13 23:18:37 +00:00
BlockFrequencyTerminology.rst blockfreq: Document BlockFrequencyInfo terminology 2014-04-11 23:21:07 +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 Document recently added sphinx documentation options in 2014-04-29 16:13:27 +00:00
CMakeLists.txt Added Sphinx documentation generation to CMake build system. 2014-04-18 21:45:25 +00:00
CodeGenerator.rst [docs] Fix up some links to the preferred style. 2014-04-08 21:06:22 +00:00
CodingStandards.rst C++11: Compatibility with (C++03 => MSVC) 2014-04-17 18:02:36 +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 the copyright credits -- Happy new year 2014! 2014-01-01 08:27:31 +00:00
DebuggingJITedCode.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +00:00
DeveloperPolicy.rst [docs] Clean up some more llvm-gcc stuff 2014-02-19 00:12:34 +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: support stack probe emission for Windows on ARM 2014-04-30 07:05:07 +00:00
FAQ.rst remove an old entry whose link is broken anyway 2014-03-02 06:37:03 +00:00
GarbageCollection.rst Remove projects/sample. 2014-03-12 22:40:22 +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 Remove projects/sample. 2014-03-12 22:40:22 +00:00
GettingStartedVS.rst [docs] Fix up some links to the preferred style. 2014-04-08 21:06:22 +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] Fix some Sphinx warnings. 2014-03-02 00:21:42 +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 blockfreq: Document BlockFrequencyInfo terminology 2014-04-11 23:21:07 +00:00
LangRef.rst [IR] Make {extract,insert}element accept an index of any integer type. 2014-05-01 22:12:39 +00:00
Lexicon.rst [docs] PR15254: Add "AST" to the lexicon. 2013-02-13 21:17:20 +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 Makefile.sphinx: reST conversion is complete! 2012-12-12 21:35:43 +00:00
MakefileGuide.rst Remove projects/sample. 2014-03-12 22:40:22 +00:00
MarkedUpDisassembly.rst docs: Fix long standing linking antipattern. 2013-01-11 02:28:08 +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 Adding a document to describe the MCJIT execution engine implementation. 2013-08-21 22:15:09 +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 Remove -simplify-libcalls pass form Passes documentation 2014-04-18 21:19:06 +00:00
Phabricator.rst Make docs point to new domain. 2014-04-07 10:21:33 +00:00
ProgrammersManual.rst Update post-r203364 http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140303/207915.html 2014-05-01 12:33:26 +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 Update release notes with EHABI current behaviour 2014-03-24 11:02:38 +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 Switch the type field in DIVariable and DIGlobalVariable over to DITypeRefs. 2014-03-18 02:34:58 +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 Cleanup docs about lit substitutions 2014-02-15 08:35:56 +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 Fix whitespace in vectorizer example 2014-03-12 23:58:07 +00:00
WritingAnLLVMBackend.rst [docs] Fix some links 2014-04-07 22:46:40 +00:00
WritingAnLLVMPass.rst fix RST reference in Writing an LLVM Pass 2013-10-30 17:09:32 +00:00
yaml2obj.rst Object: rename ARMV7 to ARMNT 2014-03-11 03:08:37 +00:00
YamlIO.rst YAMLIO: Allow scalars to dictate quotation rules 2014-04-10 07:37:33 +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