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@ -44,21 +44,21 @@ Release Notes</a>.</h1>
<div>
<p>This document contains the release notes for the LLVM Compiler
Infrastructure, release 3.0. Here we describe the status of LLVM, including
major improvements from the previous release and significant known problems.
All LLVM releases may be downloaded from the <a
href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Infrastructure, release 3.0. Here we describe the status of LLVM, including
major improvements from the previous release and significant known problems.
All LLVM releases may be downloaded from
the <a href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
<p>For more information about LLVM, including information about the latest
release, please check out the <a href="http://llvm.org/">main LLVM
web site</a>. If you have questions or comments, the <a
href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
Mailing List</a> is a good place to send them.</p>
release, please check out the <a href="http://llvm.org/">main LLVM web
site</a>. If you have questions or comments,
the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM
Developer's Mailing List</a> is a good place to send them.</p>
<p>Note that if you are reading this file from a Subversion checkout or the
main LLVM web page, this document applies to the <i>next</i> release, not the
current one. To see the release notes for a specific release, please see the
<a href="http://llvm.org/releases/">releases page</a>.</p>
<p>Note that if you are reading this file from a Subversion checkout or the main
LLVM web page, this document applies to the <i>next</i> release, not the
current one. To see the release notes for a specific release, please see the
<a href="http://llvm.org/releases/">releases page</a>.</p>
</div>
@ -78,13 +78,12 @@ current one. To see the release notes for a specific release, please see the
<!-- *********************************************************************** -->
<div>
<p>
The LLVM 3.0 distribution currently consists of code from the core LLVM
repository (which roughly includes the LLVM optimizers, code generators
and supporting tools), the Clang repository and the llvm-gcc repository. In
addition to this code, the LLVM Project includes other sub-projects that are in
development. Here we include updates on these subprojects.
</p>
<p>The LLVM 3.0 distribution currently consists of code from the core LLVM
repository (which roughly includes the LLVM optimizers, code generators and
supporting tools), the Clang repository and the llvm-gcc repository. In
addition to this code, the LLVM Project includes other sub-projects that are
in development. Here we include updates on these subprojects.</p>
<!--=========================================================================-->
<h3>
@ -94,35 +93,47 @@ development. Here we include updates on these subprojects.
<div>
<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
C++, and Objective-C languages. Clang aims to provide a better user experience
through expressive diagnostics, a high level of conformance to language
standards, fast compilation, and low memory use. Like LLVM, Clang provides a
modular, library-based architecture that makes it suitable for creating or
integrating with other development tools. Clang is considered a
production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
(32- and 64-bit), and for darwin/arm targets.</p>
C++, and Objective-C languages. Clang aims to provide a better user
experience through expressive diagnostics, a high level of conformance to
language standards, fast compilation, and low memory use. Like LLVM, Clang
provides a modular, library-based architecture that makes it suitable for
creating or integrating with other development tools. Clang is considered a
production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
(32- and 64-bit), and for darwin/arm targets.</p>
<p>In the LLVM 3.0 time-frame, the Clang team has made many improvements:</p>
<ul>
<li>Greatly improved support for building C++ applications, with greater stability and better diagnostics.</li>
<li>Greatly improved support for building C++ applications, with greater
stability and better diagnostics.</li>
<li><a href="http://clang.llvm.org/cxx_status.html">Improved support</a> for the <a href="http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50372 ">C++ 2011</a> standard, including implementations of non-static data member initializers, alias templates, delegating constructors, the range-based for loop, and implicitly-generated move constructors and move assignment operators, among others.</li>
<li><a href="http://clang.llvm.org/cxx_status.html">Improved support</a> for
the <a href="http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50372">C++
2011</a> standard, including implementations of non-static data member
initializers, alias templates, delegating constructors, the range-based
for loop, and implicitly-generated move constructors and move assignment
operators, among others.</li>
<li>Implemented support for some features of the upcoming C1x standard, including static assertions and generic selections.</li>
<li>Implemented support for some features of the upcoming C1x standard,
including static assertions and generic selections.</li>
<li>Better detection of include and linking paths for system headers and libraries, especially for Linux distributions.</li>
<li>Better detection of include and linking paths for system headers and
libraries, especially for Linux distributions.</li>
<li>Implemented support for <a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">Automatic Reference Counting</a> for Objective-C.</li>
<li>Implemented support
for <a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">Automatic
Reference Counting</a> for Objective-C.</li>
<li>Implemented a number of optimizations in <tt>libclang</tt>, the Clang C interface, to improve the performance of code completion and the mapping from source locations to abstract syntax tree nodes.</li>
<li>Implemented a number of optimizations in <tt>libclang</tt>, the Clang C
interface, to improve the performance of code completion and the mapping
from source locations to abstract syntax tree nodes.</li>
</ul>
<p>If Clang rejects your code but another compiler accepts it, please take a
look at the <a href="http://clang.llvm.org/compatibility.html">language
compatibility</a> guide to make sure this is not intentional or a known issue.
</p>
look at the <a href="http://clang.llvm.org/compatibility.html">language
compatibility</a> guide to make sure this is not intentional or a known
issue.</p>
</div>
@ -132,20 +143,17 @@ compatibility</a> guide to make sure this is not intentional or a known issue.
</h3>
<div>
<p>
<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
optimizers and code generators with LLVM's.
Currently it requires a patched version of gcc-4.5.
The plugin can target the x86-32 and x86-64 processor families and has been
used successfully on the Darwin, FreeBSD and Linux platforms.
The Ada, C, C++ and Fortran languages work well.
The plugin is capable of compiling plenty of Obj-C, Obj-C++ and Java but it is
not known whether the compiled code actually works or not!
</p>
<p><a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
optimizers and code generators with LLVM's. Currently it requires a patched
version of gcc-4.5. The plugin can target the x86-32 and x86-64 processor
families and has been used successfully on the Darwin, FreeBSD and Linux
platforms. The Ada, C, C++ and Fortran languages work well. The plugin is
capable of compiling plenty of Obj-C, Obj-C++ and Java but it is not known
whether the compiled code actually works or not!</p>
<p>The 3.0 release has the following notable changes:</p>
<p>
The 3.0 release has the following notable changes:
<ul>
<!--
<li></li>
@ -160,15 +168,15 @@ The 3.0 release has the following notable changes:
</h3>
<div>
<p>
The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
is a simple library that provides an implementation of the low-level
target-specific hooks required by code generation and other runtime components.
For example, when compiling for a 32-bit target, converting a double to a 64-bit
unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
function. The compiler-rt library provides highly optimized implementations of
this and other low-level routines (some are 3x faster than the equivalent
libgcc routines).</p>
<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
is a simple library that provides an implementation of the low-level
target-specific hooks required by code generation and other runtime
components. For example, when compiling for a 32-bit target, converting a
double to a 64-bit unsigned integer is compiled into a runtime call to the
"__fixunsdfdi" function. The compiler-rt library provides highly optimized
implementations of this and other low-level routines (some are 3x faster than
the equivalent libgcc routines).</p>
<p>In the LLVM 3.0 timeframe,</p>
@ -180,19 +188,12 @@ libgcc routines).</p>
</h3>
<div>
<p>
<a href="http://lldb.llvm.org/">LLDB</a> is a brand new member of the LLVM
umbrella of projects. LLDB is a next generation, high-performance debugger. It
is built as a set of reusable components which highly leverage existing
libraries in the larger LLVM Project, such as the Clang expression parser, the
LLVM disassembler and the LLVM JIT.</p>
<p>
LLDB is has advanced by leaps and bounds in the 3.0 timeframe. It is
dramatically more stable and useful, and includes both a new <a
href="http://lldb.llvm.org/tutorial.html">tutorial</a> and a <a
href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
GDB</a>.</p>
<p>LLDB has advanced by leaps and bounds in the 3.0 timeframe. It is
dramatically more stable and useful, and includes both a
new <a href="http://lldb.llvm.org/tutorial.html">tutorial</a> and
a <a href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
GDB</a>.</p>
</div>
@ -202,20 +203,10 @@ GDB</a>.</p>
</h3>
<div>
<p>
<a href="http://libcxx.llvm.org/">libc++</a> is another new member of the LLVM
family. It is an implementation of the C++ standard library, written from the
ground up to specifically target the forthcoming C++'0X standard and focus on
delivering great performance.</p>
<p>
In the LLVM 3.0 timeframe,</p>
<p>
Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
licensed</a> under the MIT and UIUC license, allowing it to be used more
permissively.
</p>
<p>Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
licensed</a> under the MIT and UIUC license, allowing it to be used more
permissively.</p>
</div>
@ -226,13 +217,14 @@ Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
</h3>
<div>
<p>
<a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
module and displays its contents as an expandable tree view, facilitating an
easy way to inspect types, functions, global variables, or metadata nodes. It
is fully cross-platform, being based on the popular wxWidgets GUI toolkit.
</p>
<p><a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
module and displays its contents as an expandable tree view, facilitating an
easy way to inspect types, functions, global variables, or metadata nodes. It
is fully cross-platform, being based on the popular wxWidgets GUI
toolkit.</p>
</div>
<!--=========================================================================-->
@ -241,13 +233,14 @@ Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
</h3>
<div>
<p>The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation
of a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
just-in-time compilation. As of LLVM 3.0, VMKit now supports generational
garbage collectors. The garbage collectors are provided by the MMTk framework,
and VMKit can be configured to use one of the numerous implemented collectors
of MMTk.
</p>
of a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
just-in-time compilation. As of LLVM 3.0, VMKit now supports generational
garbage collectors. The garbage collectors are provided by the MMTk
framework, and VMKit can be configured to use one of the numerous implemented
collectors of MMTk.</p>
</div>
@ -501,14 +494,14 @@ object-oriented programming, operator overloading and strong typing.</p>
co-design flow from C/C++ programs down to synthesizable VHDL and parallel
program binaries. Processor customization points include the register files,
function units, supported operations, and the interconnection network.</p>
<p>TCE uses Clang and LLVM for C/C++ language support, target independent
optimizations and also for parts of code generation. It generates new
LLVM-based code generators <i>on the fly</i> for the designed TTA processors
and loads them in to the compiler backend as runtime libraries to avoid
LLVM-based code generators "on the fly" for the designed TTA processors and
loads them in to the compiler backend as runtime libraries to avoid
per-target recompilation of larger parts of the compiler chain.</p>
</div>
</div>
<!--=========================================================================-->
<h3>Tart Programming Language</h3>
@ -657,9 +650,8 @@ Faust compiler can now generate LLVM bitcode, and works with LLVM 2.7-3.0.</p>
<div>
<p>This release includes a huge number of bug fixes, performance tweaks and
minor improvements. Some of the major improvements and new features are listed
in this section.
</p>
minor improvements. Some of the major improvements and new features are
listed in this section.</p>
<!--=========================================================================-->
<h3>
@ -686,8 +678,9 @@ in this section.
</h3>
<div>
<p>LLVM IR has several new features for better support of new targets and that
expose new optimization opportunities:</p>
expose new optimization opportunities:</p>
<p>One of the biggest changes is that 3.0 has a new exception handling
system. The old system used LLVM intrinsics to convey the exception handling
@ -810,7 +803,8 @@ Builder.CreateResume(UnwindData);
<div>
<p>In addition to a large array of minor performance tweaks and bug fixes, this
release includes a few major enhancements and additions to the optimizers:</p>
release includes a few major enhancements and additions to the
optimizers:</p>
<ul>
<!--
@ -828,11 +822,11 @@ release includes a few major enhancements and additions to the optimizers:</p>
</h3>
<div>
<p>
The LLVM Machine Code (aka MC) subsystem was created to solve a number
of problems in the realm of assembly, disassembly, object file format handling,
and a number of other related areas that CPU instruction-set level tools work
in.</p>
<p>The LLVM Machine Code (aka MC) subsystem was created to solve a number of
problems in the realm of assembly, disassembly, object file format handling,
and a number of other related areas that CPU instruction-set level tools work
in.</p>
<ul>
<!--
@ -840,10 +834,9 @@ in.</p>
-->
</ul>
<p>For more information, please see the <a
href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the
LLVM MC Project Blog Post</a>.
</p>
<p>For more information, please see
the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro
to the LLVM MC Project Blog Post</a>.</p>
</div>
@ -855,8 +848,8 @@ LLVM MC Project Blog Post</a>.
<div>
<p>We have put a significant amount of work into the code generator
infrastructure, which allows us to implement more aggressive algorithms and make
it run faster:</p>
infrastructure, which allows us to implement more aggressive algorithms and
make it run faster:</p>
<ul>
<!--
@ -871,14 +864,16 @@ it run faster:</p>
</h3>
<div>
<p>New features and major changes in the X86 target include:
</p>
<p>New features and major changes in the X86 target include:</p>
<ul>
<li>The CRC32 intrinsics have been renamed. The intrinsics were previously
@llvm.x86.sse42.crc32.[8|16|32] and @llvm.x86.sse42.crc64.[8|64]. They have
been renamed to @llvm.x86.sse42.crc32.32.[8|16|32] and
@llvm.x86.sse42.crc32.64.[8|64].</li>
<li>The CRC32 intrinsics have been renamed. The intrinsics were previously
<code>@llvm.x86.sse42.crc32.[8|16|32]</code>
and <code>@llvm.x86.sse42.crc64.[8|64]</code>. They have been renamed to
<code>@llvm.x86.sse42.crc32.32.[8|16|32]</code> and
<code>@llvm.x86.sse42.crc32.64.[8|64]</code>.</li>
</ul>
@ -890,8 +885,8 @@ it run faster:</p>
</h3>
<div>
<p>New features of the ARM target include:
</p>
<p>New features of the ARM target include:</p>
<ul>
<!--
@ -906,11 +901,13 @@ it run faster:</p>
</h3>
<div>
<ul>
<!--
<li></li>
-->
</ul>
</div>
<!--=========================================================================-->
@ -942,10 +939,12 @@ it run faster:</p>
<h4>Windows (32-bit)</h4>
<div>
<ul>
<li>On Win32(MinGW32 and MSVC), Windows 2000 will not be supported.
Windows XP or higher is required.</li>
</ul>
</div>
</div>
@ -961,24 +960,25 @@ it run faster:</p>
LLVM API changes are:</p>
<ul>
<li>The biggest and most pervasive change is that llvm::Type's are no longer
returned or accepted as 'const' values. Instead, just pass around non-const
Type's.</li>
<li>The biggest and most pervasive change is that llvm::Type's are no longer
returned or accepted as 'const' values. Instead, just pass around
non-const Type's.</li>
<li><code>PHINode::reserveOperandSpace</code> has been removed. Instead, you
must specify how many operands to reserve space for when you create the
PHINode, by passing an extra argument into <code>PHINode::Create</code>.</li>
<li><code>PHINode::reserveOperandSpace</code> has been removed. Instead, you
must specify how many operands to reserve space for when you create the
PHINode, by passing an extra argument
into <code>PHINode::Create</code>.</li>
<li>PHINodes no longer store their incoming BasicBlocks as operands. Instead,
the list of incoming BasicBlocks is stored separately, and can be accessed
with new functions <code>PHINode::block_begin</code>
and <code>PHINode::block_end</code>.</li>
<li>PHINodes no longer store their incoming BasicBlocks as operands. Instead,
the list of incoming BasicBlocks is stored separately, and can be accessed
with new functions <code>PHINode::block_begin</code>
and <code>PHINode::block_end</code>.</li>
<li>Various functions now take an <code>ArrayRef</code> instead of either a pair
of pointers (or iterators) to the beginning and end of a range, or a pointer
and a length. Others now return an <code>ArrayRef</code> instead of a
reference to a <code>SmallVector</code> or <code>std::vector</code>. These
include:
<li>Various functions now take an <code>ArrayRef</code> instead of either a
pair of pointers (or iterators) to the beginning and end of a range, or a
pointer and a length. Others now return an <code>ArrayRef</code> instead
of a reference to a <code>SmallVector</code>
or <code>std::vector</code>. These include:
<ul>
<!-- Please keep this list sorted. -->
<li><code>CallInst::Create</code></li>
@ -1021,44 +1021,45 @@ it run faster:</p>
<li><code>TargetData::getIndexedOffset</code></li>
</ul></li>
<li>All forms of <code>StringMap::getOrCreateValue</code> have been remove
except for the one which takes a <code>StringRef</code>.</li>
<li>All forms of <code>StringMap::getOrCreateValue</code> have been remove
except for the one which takes a <code>StringRef</code>.</li>
<li>The <code>LLVMBuildUnwind</code> function from the C API was removed. The
LLVM <code>unwind</code> instruction has been deprecated for a long time and
isn't used by the current front-ends. So this was removed during the
exception handling rewrite.</li>
<li>The <code>LLVMBuildUnwind</code> function from the C API was removed. The
LLVM <code>unwind</code> instruction has been deprecated for a long time
and isn't used by the current front-ends. So this was removed during the
exception handling rewrite.</li>
<li>The <code>LLVMAddLowerSetJmpPass</code> function from the C API was removed
because the <code>LowerSetJmp</code> pass was removed.</li>
<li>The <code>LLVMAddLowerSetJmpPass</code> function from the C API was
removed because the <code>LowerSetJmp</code> pass was removed.</li>
<li>The <code>DIBuilder</code> interface used by front ends to encode debugging
information in the LLVM IR now expects clients to use <code>DIBuilder::finalize()</code>
at the end of translation unit to complete debugging information encoding.</li>
<li>The <code>DIBuilder</code> interface used by front ends to encode
debugging information in the LLVM IR now expects clients to
use <code>DIBuilder::finalize()</code> at the end of translation unit to
complete debugging information encoding.</li>
<li>The way the type system works has been rewritten: <code>PATypeHolder</code>
and <code>OpaqueType</code> are gone, and all APIs deal with <code>Type*</code>
instead of <code>const Type*</code>.
If you need to create recursive structures, then create a named structure,
and use <code>setBody()</code> when all its elements are built.
Type merging and refining is gone too: named structures are not
merged with other structures, even if their layout is identical.
(of course anonymous structures are still uniqued by layout).
</li>
<li>The way the type system works has been
rewritten: <code>PATypeHolder</code> and <code>OpaqueType</code> are gone,
and all APIs deal with <code>Type*</code> instead of <code>const
Type*</code>. If you need to create recursive structures, then create a
named structure, and use <code>setBody()</code> when all its elements are
built. Type merging and refining is gone too: named structures are not
merged with other structures, even if their layout is identical. (of
course anonymous structures are still uniqued by layout).</li>
<li>TargetSelect.h moved to Support/ from Target/</li>
<li>TargetSelect.h moved to Support/ from Target/</li>
<li>UpgradeIntrinsicCall no longer upgrades pre-2.9 intrinsic calls
(for example <code>llvm.memset.i32</code>).</li>
<li>UpgradeIntrinsicCall no longer upgrades pre-2.9 intrinsic calls (for
example <code>llvm.memset.i32</code>).</li>
<li>It is mandatory to initialize all out-of-tree passes too and their dependencies now with
<code>INITIALIZE_PASS{BEGIN,END,}</code> and <code>INITIALIZE_{PASS,AG}_DEPENDENCY</code>.</li>
<li>The interface for MemDepResult in MemoryDependenceAnalysis has been enhanced
with new return types Unknown and NonFuncLocal, in addition to the existing
types Clobber, Def, and NonLocal.</li>
<li>It is mandatory to initialize all out-of-tree passes too and their dependencies now with
<code>INITIALIZE_PASS{BEGIN,END,}</code>
and <code>INITIALIZE_{PASS,AG}_DEPENDENCY</code>.</li>
<li>The interface for MemDepResult in MemoryDependenceAnalysis has been
enhanced with new return types Unknown and NonFuncLocal, in addition to
the existing types Clobber, Def, and NonLocal.</li>
</ul>
</div>
</div>
@ -1071,10 +1072,10 @@ merged with other structures, even if their layout is identical.
<div>
<p>This section contains significant known problems with the LLVM system,
listed by component. If you run into a problem, please check the <a
href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
there isn't already one.</p>
<p>This section contains significant known problems with the LLVM system, listed
by component. If you run into a problem, please check
the <a href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
there isn't already one.</p>
<!-- ======================================================================= -->
<h3>
@ -1084,18 +1085,19 @@ there isn't already one.</p>
<div>
<p>The following components of this LLVM release are either untested, known to
be broken or unreliable, or are in early development. These components should
not be relied on, and bugs should not be filed against them, but they may be
useful to some people. In particular, if you would like to work on one of these
components, please contact us on the <a
href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
be broken or unreliable, or are in early development. These components
should not be relied on, and bugs should not be filed against them, but they
may be useful to some people. In particular, if you would like to work on
one of these components, please contact us on
the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
list</a>.</p>
<ul>
<li>The Alpha, CellSPU, MicroBlaze, MSP430, MIPS, PTX,
and XCore backends are experimental.</li>
<li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets
other than darwin and ELF X86 systems.</li>
<li>The Alpha, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PTX, SystemZ and
XCore backends are experimental.</li>
<li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets other
than darwin and ELF X86 systems.</li>
</ul>
</div>
@ -1109,23 +1111,28 @@ href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
<ul>
<li>The X86 backend does not yet support
all <a href="http://llvm.org/PR879">inline assembly that uses the X86
floating point stack</a>. It supports the 'f' and 't' constraints, but not
'u'.</li>
all <a href="http://llvm.org/PR879">inline assembly that uses the X86
floating point stack</a>. It supports the 'f' and 't' constraints, but
not 'u'.</li>
<li>The X86-64 backend does not yet support the LLVM IR instruction
<tt>va_arg</tt>. Currently, front-ends support variadic
argument constructs on X86-64 by lowering them manually.</li>
<tt>va_arg</tt>. Currently, front-ends support variadic argument
constructs on X86-64 by lowering them manually.</li>
<li>Windows x64 (aka Win64) code generator has a few issues.
<ul>
<li>llvm-gcc cannot build the mingw-w64 runtime currently
due to lack of support for the 'u' inline assembly
constraint and for X87 floating point inline assembly.</li>
<li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt>
due to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>.
It is fixed in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li>
<li>llvm-gcc cannot build the mingw-w64 runtime currently due to lack of
support for the 'u' inline assembly constraint and for X87 floating
point inline assembly.</li>
<li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt> due
to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>.
It is fixed
in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li>
<li>Miss-aligned MOVDQA might crash your program. It is due to
<a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>,
lack of handling aligned internal globals.</li>
<a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>, lack
of handling aligned internal globals.</li>
</ul>
</li>
@ -1141,8 +1148,8 @@ href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
<div>
<ul>
<li>The Linux PPC32/ABI support needs testing for the interpreter and static
compilation, and lacks support for debug information.</li>
<li>The Linux PPC32/ABI support needs testing for the interpreter and static
compilation, and lacks support for debug information.</li>
</ul>
</div>
@ -1155,11 +1162,12 @@ compilation, and lacks support for debug information.</li>
<div>
<ul>
<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
processors, thumb programs can crash or produce wrong
results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
</li>
<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
processors, thumb programs can crash or produce wrong results
(<a href="http://llvm.org/PR1388">PR1388</a>).</li>
<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully
tested.</li>
</ul>
</div>
@ -1172,8 +1180,8 @@ results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
<div>
<ul>
<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
support the 64-bit SPARC ABI (-m64).</li>
<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
support the 64-bit SPARC ABI (-m64).</li>
</ul>
</div>
@ -1186,7 +1194,7 @@ results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
<div>
<ul>
<li>64-bit MIPS targets are not supported yet.</li>
<li>64-bit MIPS targets are not supported yet.</li>
</ul>
</div>
@ -1199,11 +1207,10 @@ results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
<div>
<ul>
<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
appropriate nops inserted to ensure restartability.</li>
<li>On 21164s, some rare FP arithmetic sequences which may trap do not have
the appropriate nops inserted to ensure restartability.</li>
</ul>
</div>
<!-- ======================================================================= -->
@ -1214,16 +1221,19 @@ appropriate nops inserted to ensure restartability.</li>
<div>
<p>The C backend has numerous problems and is not being actively maintained.
Depending on it for anything serious is not advised.</p>
Depending on it for anything serious is not advised.</p>
<ul>
<li><a href="http://llvm.org/PR802">The C backend has only basic support for
inline assembly code</a>.</li>
<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
C++ code compiled with <tt>llc</tt> or native compilers.</li>
<li>The C backend does not support all exception handling constructs.</li>
<li>The C backend does not support arbitrary precision integers.</li>
<li><a href="http://llvm.org/PR802">The C backend has only basic support for
inline assembly code</a>.</li>
<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
C++ programs</a>, preventing intermixing between C++ compiled by the CBE
and C++ code compiled with <tt>llc</tt> or native compilers.</li>
<li>The C backend does not support all exception handling constructs.</li>
<li>The C backend does not support arbitrary precision integers.</li>
</ul>
</div>
@ -1236,7 +1246,7 @@ Depending on it for anything serious is not advised.</p>
<div>
<p><b>LLVM 3.0 will be the last release of llvm-gcc.</b></p>
<p><b>LLVM 2.9 was the last release of llvm-gcc.</b></p>
<p>llvm-gcc is generally very stable for the C family of languages. The only
major language feature of GCC not supported by llvm-gcc is the
@ -1253,8 +1263,9 @@ Depending on it for anything serious is not advised.</p>
<a href="#dragonegg">dragonegg</a> instead.</p>
<p>The llvm-gcc 4.2 Ada compiler has basic functionality, but is no longer being
actively maintained. If you are interested in Ada, we recommend that you
consider using <a href="#dragonegg">dragonegg</a> instead.</p>
actively maintained. If you are interested in Ada, we recommend that you
consider using <a href="#dragonegg">dragonegg</a> instead.</p>
</div>
</div>
@ -1267,17 +1278,16 @@ consider using <a href="#dragonegg">dragonegg</a> instead.</p>
<div>
<p>A wide variety of additional information is available on the <a
href="http://llvm.org/">LLVM web page</a>, in particular in the <a
href="http://llvm.org/docs/">documentation</a> section. The web page also
contains versions of the API documentation which is up-to-date with the
Subversion version of the source code.
You can access versions of these documents specific to this release by going
into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
<p>A wide variety of additional information is available on
the <a href="http://llvm.org/">LLVM web page</a>, in particular in
the <a href="http://llvm.org/docs/">documentation</a> section. The web page
also contains versions of the API documentation which is up-to-date with the
Subversion version of the source code. You can access versions of these
documents specific to this release by going into the "<tt>llvm/doc/</tt>"
directory in the LLVM tree.</p>
<p>If you have any questions or comments about LLVM, please feel free to contact
us via the <a href="http://llvm.org/docs/#maillist"> mailing
lists</a>.</p>
us via the <a href="http://llvm.org/docs/#maillist"> mailing lists</a>.</p>
</div>