<li><a href="#c-fe">Known problems with the C Front-end</a>
<li><a href="#c++-fe">Known problems with the C++ Front-end</a>
<li><a href="#x86-be">Known problems with the X86 Back-end</a>
- <li><a href="#sparc-be">Known problems with the Sparc Back-end</a>
+ <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
<li><a href="#c-be">Known problems with the C back-end</a>
</ul></li>
<li><a href="#additionalinfo">Additional Information</a></li>
</ol>
-<div class="doc_text">
- <p><b>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM team</a></b><p>
+<div class="doc_author">
+ <p>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM team</a><p>
</div>
<!-- *********************************************************************** -->
<div class="doc_text">
-<p>
-This is the fourth public release of the LLVM compiler infrastructure. This
+<p>This is the fourth public release of the LLVM compiler infrastructure. This
release primarily improves the <a href="#codequality">performance of the
-code</a> produced by all aspects of the LLVM compiler and adds some <a
-href="#newfeatures">new features</a>, though it does <a href="#bugfix">fix a few
-bugs</a> as well.
-</p>
-
-<p>
-At this time, LLVM is known to correctly compile and run all C & C++ SPEC
-CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks. It has
-also been used to compile <b>many</b> other programs. LLVM now also works with
-a broad variety of C++ programs, though it has still received less testing than
-the C front-end.
-</p>
+code</a> produced by all aspects of the LLVM compiler and adds many <a
+href="#newfeatures">new features</a>, and <a href="#bugfix">fixes a few
+bugs</a> as well.</p>
+
+<p> At this time, LLVM is known to correctly compile and run all C & C++
+SPEC CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks. It
+has also been used to compile <b>many</b> other programs. LLVM now also works
+with a broad variety of C++ programs, though it has still received less testing
+than the C front-end.</p>
+
+</div>
<!--=========================================================================-->
<div class="doc_subsubsection">
<a name="newfeatures">This release implements the following new features:</a>
</div>
+<div class="doc_text">
+
<ol>
<li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is
now fully implemented and supported by all transformations, native code
<li>LLVM now has new loop unrolling and loop unswitching passes.</li>
<li>The induction variable substitution pass performs linear function test
replacement and exit value replacement optimizations.</li>
+<li>LLVM now has first-class support for <a
+href="GarbageCollection.html">Accurate Garbage Collection</a>, enabling the use
+of aggressive copying and generational collectors.</li>
+<li>LLVM now includes an implementation of Andersen's interprocedural alias
+analysis algorithm.</li>
+<li>Bugpoint can <a href="http://llvm.cs.uiuc.edu/PR327">extract individual
+basic blocks</a> to track down reduce miscompilation testcases.</li>
+<li>LLVM and the C front-end now work under Win32 using the
+<a href="http://www.cygwin.com">Cygwin</a> runtime libraries.
+This includes the JIT compiler.</li>
+<li>The LLVM code generator is now being <a
+href="CodeGenerator.html">documented</a>.</li>
+<li>There is a new tool, llvm-bcanalyzer. This tool can compute basic
+statistics and bytecode density statistics on a module or function basis and
+also dump out bytecode in a textual format that is lower level than assembly
+(values are not resolved from slot numbers). It should only be of interest to
+(a) those who are working to improve the bytecode format and (b) those who
+really want to understand or document the details of the bytecode format.</li>
+<li>The <a href="BytecodeFormat.html">LLVM Bytecode file format</a> is now
+documented.</li>
+<li>LLVM now provides an <a
+href="LangRef.html#i_isunordered">llvm.isunordered</a> intrinsic for efficient
+implementation of unordered floating point comparisons.</li>
+<li>The llvmgcc front-end now supports the GCC builtins for ISO C99 floating
+point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
+<li>Now that there are more source files than can fit on a 32Kbyte command
+line (Linux's limit), there's a new utility for searching the sources. The
+llvmgrep tool in the utils directory combines an egrep and a find without
+passing filenames through the command line. This improves performance
+slightly. Simply run llvmgrep like you might egrep but leave off the file
+names.</li>
+<li>We now generate HTML documentation and man pages for the tools from a single
+source (perl-style POD files).</li>
+<li>The LLVM code generator can now dynamically load targets from shared
+objects.</li>
</ol>
+</div>
+
<!--=========================================================================-->
<div class="doc_subsubsection">
In this release, the following missing features were implemented:
</div>
+<div class="doc_text">
+
<ol>
<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
more than 256 elements</a></li>
uses of external fns by immediate constant exprs</a></li>
</ol>
+</div>
<!--=========================================================================-->
<div class="doc_subsubsection">
issues were fixed:</a>
</div>
+<div class="doc_text">
+
<ol>
<li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew
bytecode onto your terminal</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted for structure typedefs</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted
+for structure typedefs</a></li>
+<li>All documentation is now conformant to the HTML 4.01 (Strict) level.</li>
+<li>The spurious "WARNING: Found global types that are not compatible" warning
+produced when linking C++ programs has been fixed.</li>
+<li><a href="http://llvm.cs.uiuc.edu/PR391">lli Doesn't Handle Exceptions From
+Bytecode Reader</a></li>
</ol>
+</div>
+
<!--=========================================================================-->
<div class="doc_subsubsection">
In this release, the following build problems were fixed:
</div>
+<div class="doc_text">
<ol>
-<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with -disable/enable-povray and -disable-spec</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't work if you change PATH</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with
+-disable/enable-povray and -disable-spec</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't
+work if you change PATH</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR364">[llvmgcc] llvmgcc does not compile
+with gcc 3.4</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR373">[llvmgcc] obstack.h relies on
+obsolete casts-as-lvalues GCC extension</a></li>
</ol>
+</div>
<!--=========================================================================-->
<div class="doc_subsubsection">
improvements:</a>
</div>
+<div class="doc_text">
<ol>
<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem
due to long operand of getelementptr</a></li>
<li>LLVM now has infrastructure for (simple and sparse conditional) constant
propagation of function calls. It currently supports a few math library
functions like sqrt/sin/cos/etc.</li>
-</ol>
+<li>The C backend now emits <a href="http://llvm.cs.uiuc.edu/PR334">Syntactic
+loops</a> in the code to help C compilers whose optimizers do not recognize
+loops formed from gotos (like GCC).</li>
+
+<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR368">[sparcv9] null
+often spilled to constant pool</a>.</li>
+</ol>
+</div>
<!--=========================================================================-->
<div class="doc_subsubsection">
were fixed:</a>
</div>
+<div class="doc_text">
+
<p>Bugs in the LLVM Core:</p>
<ol>
-<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
-asssertion</a></li>
<li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify
incorrectly updates dominator information</a></li>
<li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack
breaks SSA form</a></li>
<li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short
to floating point cast</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable code that unwinds</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions of
-the same name, both having constant pools</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed physical register use of aliased definition</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR315">[jit] abort, don't warn, when
+missing external functions encountered</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
+asssertion</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable
+code that unwinds</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparcv9] LLC can't emit 2 functions
+of the same name, both having constant pools</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed
+physical register use of aliased definition</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR340">Verifier misses malformed switch
+instruction</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR365">[asmwriter] Asm writer aborts if
+an instruction is not embedded into a function</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR369">[X86] stackifier crash on floating
+point setcc X, X</a></li>
</ol>
<p>Bugs in the C/C++ front-end:</p>
<ol>
-<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared enum type</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array indexing miscompiled</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array
+indexing miscompiled</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared
+enum type</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR355">[llvmgcc] Errors handling function
+prototypes that take opaque structs by-value</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR374">[llvmgcc] Crash compiling variable
+length array of structures</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR377">[llvmgcc] miscompilation of staticly
+initialized unsigned bitfields</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR396">[llvm-gcc] Crash casting function to void</a></li>
</ol>
-
</div>
<!-- *********************************************************************** -->
<div class="doc_text">
-<p>LLVM has been extensively tested on Intel and AMD machines running Red Hat
-Linux. It has also been tested under FreeBSD, and on Sun UltraSPARC
-workstations running Solaris 8. Additionally, LLVM works on Mac OS X 10.3 and
-above, but only with the C backend and interpreter; no native machine-code
-generator for the PowerPC is available yet.</p>
+<p>LLVM is known to work in the following platforms:</p>
+
+<ul>
+<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
+ other unix-like systems).</li>
+<li>Sun UltraSPARC workstations running Solaris 8.</li>
+<li>PowerPC-based Mac OS X boxes, running 10.3 and above (C backend and
+ interpreter only, no native codegen is available yet).</li>
+<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
+</ul>
+
<p>The core LLVM infrastructure uses
<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
porting may be required to get LLVM to work on new platforms. We welcome your
portability patches and reports of successful builds or error messages.</p>
+<p>Note that the LLVM build system does not currently support directories with
+spaces on them when running on Win32/cygwin. We strongly recommend running
+LLVM and the C frontend out of a top-level directory without spaces (e.g.,
+<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
+cygwin packages. By default, many important tools are not installed that
+are needed by the LLVM build process or test suite (e.g., /bin/time).</p>
+
</div>
<!--=========================================================================-->
In this release, the following portability problems were fixed:
</div>
+<div class="doc_text">
+
<ol>
-<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler on Mac OS X</a></li>
-<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't understand abbreviated names in headers</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler
+on Mac OS X</a></li>
+<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't
+understand abbreviated names in headers</a></li>
</ol>
+</div>
+
<!-- *********************************************************************** -->
<div class="doc_section">
<a name="knownproblems">Known Problems</a>
<div class="doc_text">
-<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 llvmdev list.
-</p>
+<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 llvmdev list.</p>
<ul>
<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
- -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
+ -ipmodref, -cee</tt></li>
<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
it should) and not thoroughly tested.</li>
}
</pre></li>
-<li>
-Initialization of global union variables can only be done
-<a href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest
-union member</a>.
-</li>
+<li>Initialization of global union variables can only be done <a
+href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
+member</a>.</li>
<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
external function is re-declared as static</a></li>
We support all builtins which have a C language equivalent (e.g.,
<tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
<tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
- <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
-
+ <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
+ (currently ignored). We also support builtins for ISO C99 floating
+ point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
</ol>
<p>The following extensions <b>are</b> known to be supported:</p>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Typeof.html#Typeof">Typeof</a>: <code>typeof</code>: referring to the type of an expression.</li>
- <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
+ <li><a href="http://gcc.gnu.org/onlinedocs/gcc-3.4.0/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
<li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
<div class="doc_text">
<ul>
-<li>None so far.
+ <li>Optimized (Release) versions of LLVM built with GCC 3.3.2 or 3.3.3 will
+ produce an llc tool that always enters an infinite loop due to what
+ appears to be an optimization bug (-O2 and -O3) in those versions of GCC.
+ This problem does not happen in GCC 3.3.1 nor GCC 3.4.0 nor does it happen if
+ you build a Debug version of LLVM. You are cautioned not to use GCC 3.3.2 or
+ GCC 3.3.3 to build Optimized versions of LLVM. It is unclear whether this problem
+ affects other backends but it is unlikely.</li>
</ul>
</div>
<!-- ======================================================================= -->
<div class="doc_subsection">
- <a name="sparc-be">Known problems with the Sparc back-end</a>
+ <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
</div>
<div class="doc_text">
<ul>
-<li>There are several programs in the LLVM testsuite that the Sparc code generator is known to miscompile.</li>
+<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
+several programs in the LLVM test suite</a></li>
</ul>
</div>