[llvm-commits] CVS: llvm-www/releases/2.1/docs/ReleaseNotes.html

Tanya Lattner tonic at nondot.org
Wed Sep 26 22:56:15 PDT 2007



Changes in directory llvm-www/releases/2.1/docs:

ReleaseNotes.html updated: 1.1 -> 1.2
---
Log message:

Add correct release notes.


---
Diffs of the changes:  (+185 -356)

 ReleaseNotes.html |  541 ++++++++++++++++++------------------------------------
 1 files changed, 185 insertions(+), 356 deletions(-)


Index: llvm-www/releases/2.1/docs/ReleaseNotes.html
diff -u llvm-www/releases/2.1/docs/ReleaseNotes.html:1.1 llvm-www/releases/2.1/docs/ReleaseNotes.html:1.2
--- llvm-www/releases/2.1/docs/ReleaseNotes.html:1.1	Thu Sep 27 00:43:13 2007
+++ llvm-www/releases/2.1/docs/ReleaseNotes.html	Thu Sep 27 00:55:55 2007
@@ -4,11 +4,11 @@
 <head>
   <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
   <link rel="stylesheet" href="llvm.css" type="text/css">
-  <title>LLVM 2.0 Release Notes</title>
+  <title>LLVM 2.1 Release Notes</title>
 </head>
 <body>
 
-<div class="doc_title">LLVM 2.0 Release Notes</div>
+<div class="doc_title">LLVM 2.1 Release Notes</div>
  
 <ol>
   <li><a href="#intro">Introduction</a></li>
@@ -32,7 +32,7 @@
 <div class="doc_text">
 
 <p>This document contains the release notes for the LLVM compiler
-infrastructure, release 2.0.  Here we describe the status of LLVM, including
+infrastructure, release 2.1.  Here we describe the status of LLVM, including
 major improvements from the previous release and any known problems.  All LLVM
 releases may be downloaded from the <a href="http://llvm.org/releases/">LLVM
 releases web site</a>.</p>
@@ -44,10 +44,9 @@
 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 the current or previous releases, see the <a
-href="http://llvm.org/releases/">releases page</a>.</p>
+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 releases, please see the
+<a href="http://llvm.org/releases/">releases page</a>.</p>
 
 </div>
 
@@ -59,416 +58,235 @@
 
 <div class="doc_text">
 
-<p>This is the eleventh public release of the LLVM Compiler Infrastructure. 
-Being the first major release since 1.0, this release is different in several
-ways from our previous releases:</p>
-
-<ol>
-<li>We took this as an opportunity to
-break backwards compatibility with the LLVM 1.x bytecode and .ll file format.
-If you have LLVM 1.9 .ll files that you would like to upgrade to LLVM 2.x, we 
-recommend the use of the stand alone <a href="#llvm-upgrade">llvm-upgrade</a>
-tool (which is included with 2.0).  We intend to keep compatibility with .ll 
-and .bc formats within the 2.x release series, like we did within the 1.x 
-series.</li>
-<li>There are several significant change to the LLVM IR and internal APIs, such
-    as a major overhaul of the type system, the completely new bitcode file
-    format, etc (described below).</li>
-<li>We designed the release around a 6 month release cycle instead of the usual
-    3-month cycle.  This gave us extra time to develop and test some of the
-    more invasive features in this release.</li>
-<li>LLVM 2.0 no longer supports the llvm-gcc3 front-end.  Users are required to
-    upgrade to llvm-gcc4.  llvm-gcc4 includes many features over
-    llvm-gcc3, is faster, and is <a href="CFEBuildInstrs.html">much easier to
-    build from source</a>.</li>
-</ol>
-
-<p>Note that while this is a major version bump, this release has been
-   extensively tested on a wide range of software.  It is easy to say that this
-   is our best release yet, in terms of both features and correctness.  This is
-   the first LLVM release to correctly compile and optimize major software like
-   LLVM itself, Mozilla/Seamonkey, Qt 4.3rc1, kOffice, etc out of the box on
-   linux/x86.
-   </p>
+<p>This is the twelfth public release of the LLVM Compiler Infrastructure. 
+It includes many features and refinements from LLVM 2.0.</p>
 
 </div>
 
 <!--=========================================================================-->
 <div class="doc_subsection">
-<a name="newfeatures">New Features in LLVM 2.0</a>
+<a name="frontends">New Frontends</a>
 </div>
 
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="majorchanges">Major Changes</a></div>
 <div class="doc_text">
 
-<p>Changes to the LLVM IR itself:</p>
-
-<ul>
-
-<li>Integer types are now completely signless. This means that we
-    have types like i8/i16/i32 instead of ubyte/sbyte/short/ushort/int
-    etc. LLVM operations that depend on sign have been split up into 
-    separate instructions (<a href="http://llvm.org/PR950">PR950</a>).  This
-    eliminates cast instructions that just change the sign of the operands (e.g.
-    int -> uint), which reduces the size of the IR and makes optimizers
-    simpler to write.</li>
+<p>LLVM 2.1 brings two new beta C front-ends.  First, a new version of llvm-gcc
+based on GCC 4.2, innovatively called "llvm-gcc-4.2".  This promises to bring
+FORTRAN and Ada support to LLVM as well as features like atomic builtins and
+OpenMP.  None of these actually work yet, but don't let that stop you checking
+it out!</p>
 
-<li>Integer types with arbitrary bitwidths (e.g. i13, i36, i42, i1057, etc) are
-    now supported in the LLVM IR and optimizations (<a 
-    href="http://llvm.org/PR1043">PR1043</a>).  However, neither llvm-gcc
-    (<a href="http://llvm.org/PR1284">PR1284</a>) nor the native code generators
-    (<a href="http://llvm.org/PR1270">PR1270</a>) support non-standard width
-    integers yet.</li>
+<p>Second, LLVM now includes its own native C and Objective-C front-end (C++ is
+in progress, but is not very far along) code named "<a
+href="http://clang.llvm.org/">clang</a>".  This front-end has a number of great
+features, primarily aimed at source-level analysis and speeding up compile-time.
+At this point though, the LLVM Code Generator component is still very early in
+development, so it's mostly useful for people looking to build source-level
+analysis tools or source-to-source translators.</p>
 
-<li>'Type planes' have been removed (<a href="http://llvm.org/PR411">PR411</a>).
-    It is no longer possible to have two values with the same name in the 
-    same symbol table.  This simplifies LLVM internals, allowing significant 
-    speedups.</li>
-
-<li>Global variables and functions in .ll files are now prefixed with
-    @ instead of % (<a href="http://llvm.org/PR645">PR645</a>).</li>
+</div>
 
-<li>The LLVM 1.x "bytecode" format has been replaced with a  
-    completely new binary representation, named 'bitcode'. The <a
-    href="BitCodeFormat.html">Bitcode Format</a> brings a
-    number of advantages to the LLVM over the old bytecode format: it is denser  
-    (files are smaller), more extensible, requires less memory to read,  
-    is easier to keep backwards compatible (so LLVM 2.5 will read 2.0 .bc  
-    files), and has many other nice features.</li>
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="optimizer">Optimizer Improvements</a>
+</div>
 
-<li>Load and store instructions now track the alignment of their pointer
-    (<a href="http://www.llvm.org/PR400">PR400</a>).  This allows the IR to
-    express loads that are not sufficiently aligned (e.g. due to '<tt>#pragma
-    packed</tt>') or to capture extra alignment information.</li>
-</ul>
+<div class="doc_text">
 
-<p>Major new features:</p>
+<p>Some of the most noticable feature improvements this release have been in the
+optimizer, speeding it up and making it more aggressive.  For example:</p>
 
 <ul>
 
-<li>A number of ELF features are now supported by LLVM, including 'visibility',
-    extern weak linkage, Thread Local Storage (TLS) with the <tt>__thread</tt>
-    keyword, and symbol aliases.
-    Among other things, this means that many of the special options needed to
-    configure llvm-gcc on linux are no longer needed, and special hacks to build
-    large C++ libraries like Qt are not needed.</li>
+<li>Owen Anderson wrote the new MemoryDependenceAnalysis pass, which provides 
+    a lazy, caching layer on top of <a 
+    href="AliasAnalysis.html">AliasAnalysis</a>.  He then used it to rewrite
+    DeadStoreElimination which resulted in significantly better compile time in 
+    common cases, </li>
+<li>Owen implemented the new GVN pass, which is also based on 
+    MemoryDependenceAnalysis.  This pass replaces GCSE/LoadVN in the standard
+    set of passes, providing more aggressive optimization at a some-what 
+    improved compile-time cost.</li>
+<li>Owen implemented GVN-PRE, a partial redundancy elimination algorithm that
+    shares some details with the new GVN pass.  It is still in need of compile
+    time tuning, and is not turned on by default.</li>
+<li>Devang merged ETForest and DomTree into a single easier to use data
+    structure.  This makes it more obvious which datastructure to choose
+    (because there is only one) and makes the compiler more memory and time
+    efficient (less stuff to keep up-to-date).</li>
+<li>Nick Lewycky improved loop trip count analysis to handle many more common
+    cases.</li>
 
-<li>LLVM now has a new MSIL backend. <tt>llc -march=msil</tt> will now turn LLVM
-    into MSIL (".net") bytecode.  This is still fairly early development 
-    with a number of limitations.</li>
-
-<li>A new <a href="CommandGuide/html/llvm-upgrade.html">llvm-upgrade</a> tool 
-    exists to migrates LLVM 1.9 .ll files to LLVM 2.0 syntax.</li>
 </ul>
 
 </div>
 
-
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="llvmgccfeatures">llvm-gcc
-Improvements</a></div>
-<div class="doc_text">
-<p>New features include:
-</p>
-
-<ul>
-<li>Precompiled Headers (PCH) are now supported.</li>
-
-<li>"<tt>#pragma packed</tt>" is now supported, as are the various features
-    described above (visibility, extern weak linkage, __thread, aliases,
-    etc).</li>
-
-<li>Tracking function parameter/result attributes is now possible.</li>
-
-<li>Many internal enhancements have been added, such as improvements to
-    NON_LVALUE_EXPR, arrays with non-zero base, structs with variable sized
-    fields, VIEW_CONVERT_EXPR, CEIL_DIV_EXPR, nested functions, and many other
-    things.  This is primarily to supports non-C GCC front-ends, like Ada.</li>
-
-<li>It is simpler to configure llvm-gcc for linux.</li>
-
-</ul>
-  
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="codegen">Code Generator Improvements</a>
 </div>
 
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="optimizer">Optimizer
-Improvements</a></div>
-
 <div class="doc_text">
-<p>New features include:
-</p>
-
-<ul>
-<li>The <a href="WritingAnLLVMPass.html">pass manager</a> has been entirely
-    rewritten, making it significantly smaller, simpler, and more extensible.
-    Support has been added to run <tt>FunctionPass</tt>es interlaced with
-    <tt>CallGraphSCCPass</tt>es, we now support loop transformations
-    explicitly with <tt>LoopPass</tt>, and <tt>ModulePass</tt>es may now use the
-    result of <tt>FunctionPass</tt>es.</li>
-
-<li>LLVM 2.0 includes a new loop rotation pass, which converts "for loops" into 
-    "do/while loops", where the condition is at the bottom of the loop.</li>
-
-<li>The Loop Strength Reduction pass has been improved, and we now support
-    sinking expressions across blocks to reduce register pressure.</li>
-
-<li>The <tt>-scalarrepl</tt> pass can now promote unions containing FP values
-    into a register, it can also handle unions of vectors of the same
-    size.</li>
-
-<li>The [Post]DominatorSet classes have been removed from LLVM and clients
-    switched to use the more-efficient ETForest class instead.</li>
-
-<li>The ImmediateDominator class has also been removed, and clients have been
-    switched to use DominatorTree instead.</li>
-
-<li>The predicate simplifier pass has been improved, making it able to do 
-    simple value range propagation and eliminate more conditionals.  However,
-    note that predsimplify is not enabled by default in llvm-gcc.</li>
 
-</ul>
-  
-</div>
-
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="codegen">Code
-Generator Enhancements</a></div>
-
-<div class="doc_text">
-<p>
-New features include:
-</p>
+<p>One of the main focuses of this release was performance tuning and bug
+   fixing.  In addition to these, several new major changes occurred:</p>
 
 <ul>
 
-<li>LLVM now supports software floating point, which allows LLVM to target
-    chips that don't have hardware FPUs (e.g. ARM thumb mode).</li>
-
-<li>A new register scavenger has been implemented, which is useful for
-    finding free registers after register allocation.  This is useful when
-    rewriting frame references on RISC targets, for example.</li>
+<li>Dale finished up the Tail Merging optimization in the code generator, and
+    enabled it by default.  This produces smaller code that is also faster in
+    some cases.</li>
 
-<li>Heuristics have been added to avoid coalescing vregs with very large live 
-    ranges to physregs.  This was bad because it effectively pinned the physical
-    register for the entire lifetime of the virtual register (<a 
-    href="http://llvm.org/PR711">PR711</a>).</li>
+<li>Christopher Lamb implemented support for virtual register sub-registers,
+    which can be used to better model many forms of subregisters.  As an example
+    use, he modified the X86 backend to use this to model truncates and
+    extends more accurately (leading to better code).</li>
 
-<li>Support now exists for very simple (but still very useful) 
-    rematerialization the register allocator, enough to move  
-    instructions like "load immediate" and constant pool loads.</li>
+<li>Dan Gohman changed the way we represent vectors before legalization,
+    significantly simplifying the SelectionDAG representation for these and
+    making the code generator faster for vector code.</li>
 
-<li>Switch statement lowering is significantly better, improving codegen for 
-    sparse switches that have dense subregions, and implemented support 
-    for the shift/and trick.</li>
+<li>Evan contributed a new target independent if-converter.  While it is 
+    target independent, so far only the ARM backend uses it.</li>
 
-<li>LLVM now supports tracking physreg sub-registers and super-registers 
-    in the code generator, and includes extensive register
-    allocator changes to track them.</li>
+<li>Evan rewrite the way the register allocator handles rematerialization,
+    allowing it to be much more effective on two-address targets like X86,
+    and taught it to fold loads away when possible (also a big win on X86).</li>
 
-<li>There is initial support for virtreg sub-registers 
-    (<a href="http://llvm.org/PR1350">PR1350</a>).</li>
-
-</ul>
+<li>Dan Gohman contributed support for better alignment and volatility handling
+    in the code generator, and significantly enhanced alignment analysis for SSE
+    load/store instructions.  With his changes, an insufficiently-aligned SSE
+    load instruction turns into <tt>movups</tt>, for example.</li>
 
-<p>
-Other improvements include:
-</p>
-
-<ul>
+<li>Duraid Madina contributed a new "bigblock" register allocator, and Roman
+    Levenstein contributed several big improvements.  BigBlock is optimized for
+    code that uses very large basic blocks.  It is slightly slower than the
+    "local" allocator, but produces much better code.</li>
 
-<li>Inline assembly support is much more solid that before.
-    The two primary features still missing are support for 80-bit floating point
-    stack registers on X86 (<a href="http://llvm.org/PR879">PR879</a>), and
-    support for inline asm in the C backend (<a 
-    href="http://llvm.org/PR802">PR802</a>).</li>
-
-<li>DWARF debug information generation has been improved.  LLVM now passes 
-    most of the GDB testsuite on MacOS and debug info is more dense.</li>
-
-<li>Codegen support for Zero-cost DWARF exception handling has been added (<a 
-    href="http://llvm.org/PR592">PR592</a>).  It is mostly
-    complete and just in need of continued bug fixes and optimizations at 
-    this point.  However, support in llvm-g++ is disabled with an
-    #ifdef for the 2.0 release  (<a 
-    href="http://llvm.org/PR870">PR870</a>).</li>
-
-<li>The code generator now has more accurate and general hooks for  
-    describing addressing modes ("isLegalAddressingMode") to  
-    optimizations like loop strength reduction and code sinking.</li>
-
-<li>Progress has been made on a direct Mach-o .o file writer. Many small 
-    apps work, but it is still not quite complete.</li>
+<li>David Greene refactored the register allocator to split coalescing out from
+    allocation, making coalescers pluggable.</li>
 
 </ul>
 
-<p>In addition, the LLVM target description format has itself been extended in
- several ways:</p>
- 
-<ul>
-<li>TargetData now supports better target parameterization in
-    the .ll/.bc files, eliminating the 'pointersize/endianness' attributes
-    in the files (<a href="http://llvm.org/PR761">PR761</a>).</li>
-
-<li>TargetData was generalized for finer grained alignment handling,
-    handling of vector alignment, and handling of preferred alignment</li>
-
-<li>LLVM now supports describing target calling conventions  
-    explicitly in .td files, reducing the amount of C++ code that needs  
-    to be written for a port.</li>
+</div>
 
-</ul>
 
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="targetspecific">Target Specific Improvements</a>
 </div>
 
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="specifictargets">Target-Specific
-Improvements</a></div>
-
 <div class="doc_text">
-
-<p>X86-specific Code Generator Enhancements:
+<p>New features include:
 </p>
 
 <ul>
-<li>The MMX instruction set is now supported through intrinsics.</li>
-<li>The scheduler was improved to better reduce register pressure on  
-    X86 and other targets that are register pressure sensitive.</li>
-<li>Linux/x86-64 support is much better.</li>
-<li>PIC support for linux/x86 has been added.</li>
-<li>The X86 backend now supports the GCC regparm attribute.</li>
-<li>LLVM now supports inline asm with multiple constraint letters per operand 
-    (like "mri") which is common in X86 inline asms.</li>
-</ul>
-
-<p>ARM-specific Code Generator Enhancements:</p>
-
-<ul>
-<li>The ARM code generator is now stable and fully supported.</li>
-
-<li>There are major new features, including support for ARM 
-    v4-v6 chips, vfp support, soft float point support, pre/postinc support,
-    load/store multiple generation, constant pool entry motion (to support
-    large functions), inline asm support, weak linkage support, static
-    ctor/dtor support and many bug fixes.</li>
+<li>Bruno Cardoso Lopes contributed initial MIPS support.  It is sufficient to
+    run many small programs, but is still incomplete and is not yet
+    fully performant.</li>
     
-<li>Added support for Thumb code generation (<tt>llc -march=thumb</tt>).</li>
+<li>Bill Wendling added SSSE3 support to the X86 backend.</li>
 
-<li>The ARM backend now supports the ARM AAPCS/EABI ABI and PIC codegen on 
-    arm/linux.</li>
+<li>Nicholas Geoffray contributed improved linux/ppc ABI and JIT support.</li>
 
-<li>Several bugs were fixed for DWARF debug info generation on arm/linux.</li>
+<li>Dale Johannesen rewrote handling of 32-bit float values in the X86 backend
+    when using the floating point stack, fixing several nasty bugs.</li>
 
+<li>Dan contributed rematerialization support for the X86 backend, in addition
+    to several X86-specific micro optimizations.</li>
 </ul>
+  
+</div>
 
-<p>PowerPC-specific Code Generator Enhancements:</p>
-
-<ul>
-<li>The PowerPC 64 JIT now supports addressing code loaded above the 2G
-     boundary.</li>
-
-<li>Improved support for the Linux/ppc ABI and the linux/ppc JIT is fully 
-    functional now.  llvm-gcc and static compilation are not fully supported 
-    yet though.</li>
-
-<li>Many PowerPC 64 bug fixes.</li>
-
-</ul>
 
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="llvmgccimprovements">llvm-gcc Improvements</a>
 </div>
 
-
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="other">Other Improvements</a></div>
 <div class="doc_text">
-
-<p>More specific changes include:</p>
+<p>New features include:
+</p>
 
 <ul>
-<li>LLVM no longer relies on static destructors to shut itself down.  Instead,
-    it lazily initializes itself and shuts down when <tt>llvm_shutdown()</tt> is 
-    explicitly called.</li>
-
-<li>LLVM now has significantly fewer static constructors, reducing startup time.
-    </li>
-
-<li>Several classes have been refactored to reduce the amount of code that
-    gets linked into apps that use the JIT.</li>
-
-<li>Construction of intrinsic function declarations has been simplified.</li>
-
-<li>The gccas/gccld tools have been replaced with small shell scripts.</li>
+<li>Duncan and Anton made significant progress chasing down a number of problems
+    with C++ Zero-Cost exception handling in llvm-gcc 4.0 and 4.2.  It is now at
+    the point where it "just works" on linux/X86-32 and has partial support on
+    other targets.</li>
+
+<li>Devang and Duncan fixed a huge number of bugs relating to bitfields, pragma
+    pack, and variable sized fields in structures.</li>
+
+<li>Tanya implemented support for <tt>__attribute__((noinline))</tt> in
+    llvm-gcc, and added support for generic variable annotations which are
+    propagated into the LLVM IR, e.g.
+    "<tt>int X __attribute__((annotate("myproperty")));</tt>".</li>
+
+<li>Sheng Zhou and Christopher Lamb implemented alias analysis support for
+"restrict" pointer arguments to functions.</li>
+
+<li>Duncan contributed support for trampolines (taking the address of a nested
+    function).  Currently this is only supported on the X86-32 target.</li>
+
+<li>Lauro Ramos Venancio contributed support to encode alignment info in 
+    load and store instructions, the foundation for other alignment-related
+    work.</li>
+</ul>
+  
+</div>
 
-<li>Support has been added to llvm-test for running on low-memory  
-    or slow machines (make SMALL_PROBLEM_SIZE=1).</li>
 
-</ul>
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="coreimprovements">LLVM Core Improvements</a>
 </div>
 
-<!--_________________________________________________________________________-->
-<div class="doc_subsubsection"><a name="apichanges">API Changes</a></div>
 <div class="doc_text">
-
-<p>LLVM 2.0 contains a revamp of the type system and several other significant
-internal changes.  If you are programming to the C++ API, be aware of the
-following major changes:</p>
+<p>New features include:
+</p>
 
 <ul>
-<li>Pass registration is slightly different in LLVM 2.0 (you now need an
-   <tt>intptr_t</tt> in your constructor), as explained in the <a 
-   href="WritingAnLLVMPass.html#basiccode">Writing an LLVM Pass</a>
-   document.</li>
-   
-<li><tt>ConstantBool</tt>, <tt>ConstantIntegral</tt> and <tt>ConstantInt</tt>
-    classes have been merged together, we now just have
-    <tt>ConstantInt</tt>.</li>
-
-<li><tt>Type::IntTy</tt>, <tt>Type::UIntTy</tt>, <tt>Type::SByteTy</tt>, ... are
-    replaced by <tt>Type::Int8Ty</tt>, <tt>Type::Int16Ty</tt>, etc.  LLVM types
-    have always corresponded to fixed size types
-    (e.g. long was always 64-bits), but the type system no longer includes
-    information about the sign of the type.  Also, the
-    <tt>Type::isPrimitiveType()</tt> method now returns false for integers.</li>
-
-<li>Several classes (<tt>CallInst</tt>, <tt>GetElementPtrInst</tt>,
-    <tt>ConstantArray</tt>, etc), that once took <tt>std::vector</tt> as
-     arguments now take ranges instead.   For example, you can create a
-    <tt>GetElementPtrInst</tt> with code like:
+<li>Neil Booth contributed a new "APFloat" class, which ensures that floating
+    point representation and constant folding is not dependent on the host 
+    architecture that builds the application.  This support is the foundation
+    for "long double" support that will be wrapped up in LLVM 2.2.</li>
     
-    <pre>
-      Value *Ops[] = { Op1, Op2, Op3 };
-      GEP = new GetElementPtrInst(BasePtr, Ops, 3);
-    </pre>
-    
-    This avoids creation of a temporary vector (and a call to malloc/free).  If
-    you have an <tt>std::vector</tt>, use code like this:
-    <pre>
-      std::vector<Value*> Ops = ...;
-      GEP = new GetElementPtrInst(BasePtr, &Ops[0], Ops.size());
-    </pre>
+<li>Based on the APFloat class, Dale redesigned the internals of the ConstantFP
+    class and has been working on extending the core and optimizer components to
+    support various target-specific 'long double's.  We expect this work to be
+    completed in LLVM 2.2.</li>
+
+<li>LLVM now provides an LLVMBuilder class, which makes it significantly easier
+    to create LLVM IR instructions.</li>
+
+<li>Reid contributed support for intrinsics that take arbitrary integer typed
+    arguments.  Dan Gohman and Chandler extended it to support arbitrary
+    floating point arguments and vectors.</li>
+</ul>
+  
+</div>
 
-    </li>
-    
-<li><tt>CastInst</tt> is now abstract and its functionality is split into
-    several parts, one for each of the <a href="LangRef.html#convertops">new
-    cast instructions</a>.</li>
-
-<li><tt>Instruction::getNext()/getPrev()</tt> are now private (along with
-    <tt>BasicBlock::getNext</tt>, etc), for efficiency reasons (they are now no
-    longer just simple pointers).  Please use <tt>BasicBlock::iterator</tt>, etc
-    instead.
-</li>
+<!--=========================================================================-->
+<div class="doc_subsection">
+<a name="otherimprovements">Other Improvements</a>
+</div>
 
-<li><tt>Module::getNamedFunction()</tt> is now called
-    <tt>Module::getFunction()</tt>.</li>
+<div class="doc_text">
+<p>New features include:
+</p>
 
-<li><tt>SymbolTable.h</tt> has been split into <tt>ValueSymbolTable.h</tt> and 
-<tt>TypeSymbolTable.h</tt>.</li>
+<ul>
+<li>Sterling Stein contributed a new BrainF frontend, located in llvm/examples.
+    This shows a some of the more modern APIs for building a front-end, and
+    demonstrates JIT compiler support.</li>
+
+<li>David Green contributed a new <tt>--enable-expensive-checks</tt> configure
+    option which enables STL checking, and fixed several bugs exposed by
+    it.</li>
 </ul>
+  
 </div>
 
-
 <!-- *********************************************************************** -->
 <div class="doc_section">
   <a name="portability">Portability and Supported Platforms</a>
@@ -530,12 +348,11 @@
 components, please contact us on the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
 
 <ul>
-<li>The <tt>-cee</tt> pass is known to be buggy, and may be removed in in a 
+<li>The <tt>-cee</tt> pass is known to be buggy, and may be removed in a 
     future release.</li>
-<li>C++ EH support is disabled for this release.</li>
 <li>The MSIL backend is experimental.</li>
 <li>The IA64 code generator is experimental.</li>
-<li>The Alpha JIT is experimental.</li>
+<li>The Alpha backend is experimental.</li>
 <li>"<tt>-filetype=asm</tt>" (the default) is the only supported value for the 
     <tt>-filetype</tt> llc option.</li>
 </ul>
@@ -552,6 +369,9 @@
 <ul>
 <li>The X86 backend does not yet support <a href="http://llvm.org/PR879">inline
     assembly that uses the X86 floating point stack</a>.</li>
+<li>The X86 backend occasionally has <a href="http://llvm.org/PR1649">alignment
+    problems</a> on operating systems that don't require 16-byte stack alignment
+    (including most non-darwin OS's like linux).</li>
 </ul>
 
 </div>
@@ -581,7 +401,7 @@
 
 <ul>
 <li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
-processors, thumb program can crash or produces wrong
+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>
@@ -661,6 +481,11 @@
 <ul>
 <li><a href="http://llvm.org/PR802">The C backend does not support inline
     assembly code</a>.</li>
+<li><a href="http://llvm.org/PR1126">The C backend does not support vectors
+    yet</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 LLC or native compilers.</li>
 </ul>
 
 </div>
@@ -700,9 +525,12 @@
 
 <li><p>llvm-gcc <b>partially</b> supports these GCC extensions:</p>
   <ol>
-  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html#Nested%20Functions">Nested Functions</a>: As in Algol and Pascal, lexical scoping of functions.<br>
-      Nested functions are supported, but llvm-gcc does not support non-local
-      gotos or taking the address of a nested function.</li>
+  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html#Nested%20Functions">Nested Functions</a>:
+
+      As in Algol and Pascal, lexical scoping of functions.
+      Nested functions are supported, but llvm-gcc does not support
+      taking the address of a nested function (except on the X86-32 target)
+      or non-local gotos.</li>
 
   <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
 
@@ -712,11 +540,11 @@
       <b>Supported:</b> <tt>alias</tt>, <tt>always_inline</tt>, <tt>cdecl</tt>,
       <tt>constructor</tt>, <tt>destructor</tt>,
       <tt>deprecated</tt>, <tt>fastcall</tt>, <tt>format</tt>, 
-      <tt>format_arg</tt>, <tt>non_null</tt>, <tt>noreturn</tt>, <tt>regparm</tt>
+      <tt>format_arg</tt>, <tt>non_null</tt>, <tt>noinline</tt>, <tt>noreturn</tt>, <tt>regparm</tt>
       <tt>section</tt>, <tt>stdcall</tt>, <tt>unused</tt>, <tt>used</tt>, 
       <tt>visibility</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
 
-      <b>Ignored:</b> <tt>noinline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
+      <b>Ignored:</b> <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
       <tt>malloc</tt>, <tt>no_instrument_function</tt></li>
   </ol>
 </li>
@@ -794,8 +622,9 @@
 itself, Qt, Mozilla, etc.</p>
 
 <ul>
-<li>llvm-gcc4 only has partial support for <a href="http://llvm.org/PR870">C++ 
-Exception Handling</a>, and it is not enabled by default.</li>
+<li>Exception handling only works well on the linux/X86-32 target.
+In some cases, illegally throwing an exception does not result
+in a call to terminate.</li>
 
 <!-- NO EH Support!
 
@@ -854,7 +683,7 @@
   src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
 
   <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
-  Last modified: $Date: 2007/09/27 05:43:13 $
+  Last modified: $Date: 2007/09/27 05:55:55 $
 </address>
 
 </body>






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