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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><title>LLVM 1.1 Release Notes</title></head>
<body bgcolor=white>

<table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
<tr><td>&nbsp; <font size=+3 color="#EEEEFF" face="Georgia,Palatino,Times,Roman"><b>LLVM 1.1 Release Notes</b></font></td>
</tr></table>
 
<ol>
  <li><a href="#intro">Introduction</a>
  <li><a href="#whatsnew">What's New?</a>
  <li><a href="#portability">Portability and Supported Platforms</a>
  <li><a href="#install-instructions">Installation Instructions</a>
  <li><a href="#knownproblems">Known Problems</a>
  <ul>
<!--    <li><a href="#portabilityprobs">Portability Problems</a> -->
    <li><a href="#core">Known problems with the LLVM Core</a>
    <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="#c-be">Known problems with the C back-end</a>
  </ul>
  <li><a href="#additionalinfo">Additional Information</a>
  </ul>

  <p><b>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a></b><p>
</ol>


<!-- *********************************************************************** -->
<table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
<a name="intro">Introduction
</b></font></td></tr></table><ul>
<!-- *********************************************************************** -->

This document contains the release notes for the LLVM compiler infrastructure,
release 1.1.  Here we describe the status of LLVM, including any known problems,
and bug fixes from the previous release.  The most up-to-date version of this
document can be found on the <a
href="http://llvm.cs.uiuc.edu/releases/1.1/">LLVM 1.1 web site</a>.  If you are
not reading this on the LLVM web pages, you should probably go there, because
this document may be updated after the release.<p>

For more information about LLVM, including information about potentially more
current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
web site</a>.  If you have questions or comments, the <a
href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
list</a> is a good place to send them.<p>

Note that if you are reading this file from CVS, that this document applies to
the <i>next</i> release, not the previous one.  To see the release notes for the
previous release, see the <a href="http://llvm.cs.uiuc.edu/releases/">releases
page</a>.<p>

<!-- *********************************************************************** -->
</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
<a name="whatsnew">What's New?
</b></font></td></tr></table><ul>
<!-- *********************************************************************** -->

This is the second public release of the LLVM compiler infrastructure.  This
release implements the following new features:<p>

<ol>
<li>temp</li>
<li>temp</li>
<li>temp</li>
</ol><p>

In this release, the following Quality of Implementation issues were fixed:<p>

<ol>
<li><a href="http://llvm.cs.uiuc.edu/PR29">C++ front-end is not generating linkonce linkage type when it can</a></li>
</ol><p>

In this release, the following bugs in the previous release were fixed:<p>

<ol>
<li><a href="http://llvm.cs.uiuc.edu/PR57">[inliner] Inlining invoke with PHI in unwind target is broken</a></li>
<li><a href="http://llvm.cs.uiuc.edu/PR58">[linker] linkonce globals should link successfully to external globals</a></li>
</ol><p>

At this time, LLVM is known to work properly with SPEC CPU 2000, the Olden
benchmarks, and the Ptrdist benchmarks among many other programs.  Note however
that the Sparc and X86 backends do not currently support exception throwing or
long jumping (including 253.perlbmk in SPEC).  For these programs you must use
the C backend.<p>


<!-- *********************************************************************** -->
</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
<a name="portability">Portability and Supported Platforms
</b></font></td></tr></table><ul>
<!-- *********************************************************************** -->

LLVM has only been extensively tested on Intel and AMD machines running Red
Hat Linux, and Sun UltraSPARC workstations running Solaris 8.
The core LLVM infrastructure uses "autoconf" for portability, so hopefully we
work on more platforms than that.  However, it is extremely likely that we
missed something.  We welcome portability patches and error messages.<p>


<!-- *********************************************************************** -->
</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
<a name="knownproblems">Known Problems
</b></font></td></tr></table><ul>
<!-- *********************************************************************** -->

This section contains all known problems with the LLVM system, listed by
component.  As new problems are discovered, they will be added to these
sections.


<!-- _______________________________________________________________________ -->
<!--
</ul><h4><a name="portability"><hr size=0>Portability Problems</h4><ul>
-->


<!-- _______________________________________________________________________ -->
</ul><h4><a name="core"><hr size=0>Known problems with the LLVM Core</h4><ul>

<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not work.<p>

<li>The JIT does not use mutexes to protect its internal data structures.  As
    such, execution of a threaded program could cause these data structures to
    be corrupted.<p>

<li>It is not possible to <tt>dlopen</tt> an LLVM bytecode file in the JIT.<p>

<li>Linking in static archive files (.a files) is very slow (there is no symbol
table in the archive).

<!-- _______________________________________________________________________ -->
</ul><h4><a name="c-fe"><hr size=0>Known problems with the C front-end</h4><ul>

<li>Inline assembly is not yet supported.<p>

<li>"long double" is transformed by the front-end into "double".  There is no
    support for floating point data types of any size other than 32 and 64 bits.
    <p>
<li>C99 Variable sized arrays do not release stack memory when they go out of 
    scope.  Thus, the following program may run out of stack space:
<pre>
    for (i = 0; i != 1000000; ++i) {
      int X[n];
      foo(X);
    }
</pre><p>

<li>The following Unix system functionality has not been tested and may not work:
<ol>
   <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
       appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions.  Note that
       <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
   <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
       - These functions have not been tested.
</ol><p>

<li>Bugs:<br>
  <a href="http://llvm.cs.uiuc.edu/PR6">Oversized integer bitfields cause crash</a>.<br>
<p>

<li>Although many GCC extensions are supported, some are not.  In particular,
    the following extensions are known to <b>not be</b> supported:
  <ol>
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block. 
  <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><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. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: 	Dispatching a call to another function. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>:  Constraints for asm operands
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Asm-Labels.html#Asm%20Labels">Asm Labels</a>:   Specifying the assembler name to use for a C symbol. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Vector-Extensions.html#Vector%20Extensions">Vector Extensions</a>: Using vector instructions through built-in functions. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Target-Builtins.html#Target%20Builtins">Target Builtins</a>:   Built-in functions specific to particular targets. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables. 
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC. 
  </ol><p>

  The following GCC extensions are <b>partially</b> supported.  An ignored
  attribute means that the LLVM compiler ignores the presence of the attribute,
  but the code should still work.  An unsupported attribute is one which is
  ignored by the LLVM compiler, which will cause a different interpretation of
  the program.<p>

  <ol>
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
      Arrays whose length is computed at run time.<br>
      Supported, but allocated stack space is not freed until the function returns (noted above).

  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
      Declaring that functions have no side effects, or that they can never return.<br>
      <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>, <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>, <tt>deprecated</tt>,
                 <tt>warn_unused_result</tt>, <tt>weak</tt><br>
      <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>, <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,  <tt>malloc</tt>
               <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
      <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>, <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
               <tt>fastcall</tt>, all other target specific attributes
   
  <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
      Specifying attributes of variables.<br>
      <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt