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gerrit-public.fairphone.software / toolchain / llvm-project / 0327f0bc91d3a7fd016f280c9622f749e8bdae4a / . / llvm / docs / ReleaseNotes.html
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4<head>
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Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]7 <title>LLVM 2.4 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]11<div class="doc_title">LLVM 2.4 Release Notes</div>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]13<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]14 <li><a href="#intro">Introduction</a></li>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]15 <li><a href="#subproj">Sub-project Status Update</a></li>
16 <li><a href="#whatsnew">What's New in LLVM?</a></li>
Chris Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]17 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]18 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]19 <li><a href="#knownproblems">Known Problems</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]20 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]21</ol>
22
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]23<div class="doc_author">
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]24 <p>Written by the <a href="http://llvm.org">LLVM Team</a><p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]25</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]26
27<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]28<div class="doc_section">
29 <a name="intro">Introduction</a>
30</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]31<!-- *********************************************************************** -->
32
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]33<div class="doc_text">
34
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]35<p>This document contains the release notes for the LLVM Compiler
36Infrastructure, release 2.4. Here we describe the status of LLVM, including
37major improvements from the previous release and significant known problems.
38All LLVM releases may be downloaded from the <a
39href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]40
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]41<p>For more information about LLVM, including information about the latest
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]42release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]43web site</a>. If you have questions or comments, the <a
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]44href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's Mailing
45List</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]46
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]47<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]48main LLVM web page, this document applies to the <i>next</i> release, not the
49current one. To see the release notes for a specific releases, please see the
50<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]51
52</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]53
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]54<!-- Unfinished features in 2.4:
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]55 Machine LICM
56 Machine Sinking
57 LegalizeDAGTypes
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]58 llc -enable-value-prop, propagation of value info (sign/zero ext info) from
59 one MBB to another
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]60 -->
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]61
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]62 <!-- for announcement email:
63 mention dev mtg
Chris Lattnere3df07e2008-10-12 22:57:58 +0000[diff] [blame]64 Xcode 3.1 and 3.1.1.
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]65 -->
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]66
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]67<!-- *********************************************************************** -->
68<div class="doc_section">
69 <a name="subproj">Sub-project Status Update</a>
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]70</div>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]71<!-- *********************************************************************** -->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]72
73<div class="doc_text">
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]74<p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]75The LLVM 2.4 distribution currently consists of code from the core LLVM
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]76repository (which roughly includes the LLVM optimizers, code generators and
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]77supporting tools) and the llvm-gcc repository. In addition to this code, the
78LLVM Project includes other sub-projects that are in development. The two which
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]79are the most actively developed are the <a href="#clang">Clang Project</a> and
Duncan Sandsb34d5902008-10-13 18:33:28 +0000[diff] [blame]80the <a href="#vmkit">vmkit Project</a>.
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]81</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]82
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]83</div>
84
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]85
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]86<!--=========================================================================-->
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]87<div class="doc_subsection">
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]88<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]89</div>
90
91<div class="doc_text">
92
93<p>The <a href="http://clang.llvm.org/">Clang project</a> is an effort to build
94a set of new 'LLVM native' front-end technologies for the LLVM optimizer
95and code generator. Clang is continuing to make major strides forward in all
96areas. Its C and Objective-C parsing support is very solid, and the code
97generation support is far enough along to build many C applications. While not
98yet production quality, it is progressing very nicely. In addition, C++
99front-end work has started to make significant progress.</p>
100
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]101<p>Codegen progress/state
102</p>
103
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]104</div>
105
106<!--=========================================================================-->
107<div class="doc_subsection">
108<a name="clangsa">Clang Static Analyzer</a>
109</div>
110
111<div class="doc_text">
112
113<p>The
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]114<a href="http://clang.llvm.org/StaticAnalysis.html">static analysis tool</a>
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]115.</p>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]116
117</div>
118
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]119<!--=========================================================================-->
120<div class="doc_subsection">
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]121<a name="vmkit">vmkit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]122</div>
123
124<div class="doc_text">
125<p>
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]126The <a href="http://vmkit.llvm.org/">vmkit project</a> is an implementation of
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]127a JVM and a CLI Virtual Machines (Microsoft .NET is an
128implementation of the CLI) using the Just-In-Time compiler of LLVM.</p>
129
130<p>...</p>
131
132</div>
133
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]134
135<!-- *********************************************************************** -->
136<div class="doc_section">
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]137 <a name="whatsnew">What's New in LLVM?</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]138</div>
139<!-- *********************************************************************** -->
140
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]141<div class="doc_text">
142
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]143<p>This release includes a huge number of bug fixes, performance tweaks and
144minor improvements. Some of the major improvements and new features are listed
145in this section.
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]146</p>
147</div>
148
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]149<!--=========================================================================-->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]150<div class="doc_subsection">
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]151<a name="majorfeatures">Major New Features</a>
152</div>
153
154<div class="doc_text">
155
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]156<p>LLVM 2.4 includes several major new capabilities:</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]157
158<ul>
Chris Lattner591ef272008-10-13 20:47:20 +0000[diff] [blame]159<li><p>The most visible end-user change in LLVM 2.4 is that it includes many
160optimizations and changes ot make -O0 compile times much faster. You should see
161improvements on the order of 30% or more faster than LLVM 2.3. There are many
162pieces to this change, described in more detail below. The speedups and new
163components can also be used for JIT compilers that want fast compilation as
164well.</p></li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]165
Chris Lattner591ef272008-10-13 20:47:20 +0000[diff] [blame]166<li><p>The biggest change to the LLVM IR is that Multiple Return Values (which
167were introduced in LLVM 2.3) have been generalized to full support for "First
168Class Aggregate" values in LLVM 2.4. This means that LLVM IR supports using
169structs and arrays as values in a function. This capability is mostly useful
170for front-end authors, who prefer to treat things like complex numbers, simple
171tuples, dope vectors, etc as Value*'s instead of as a tuple of Value*'s or as
172memory values.</p></li>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]173
Chris Lattner591ef272008-10-13 20:47:20 +0000[diff] [blame]174<li><p>LLVM 2.4 also includes an initial port for the PIC16 microprocessor. This
175is the LLVM targer that only has support for 8 bit registers, and a number of
176other crazy constraints. While the port is still in early development stages,
177it shows some interesting things you can do with LLVM.</p></li>
Chris Lattner618a99f2008-06-05 06:57:39 +0000[diff] [blame]178
Chris Lattner458e79f2008-02-10 08:18:42 +0000[diff] [blame]179</ul>
180
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]181</div>
182
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]183
184<!--=========================================================================-->
185<div class="doc_subsection">
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]186<a name="llvm-gcc">llvm-gcc 4.2 Improvements</a>
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]187</div>
188
189<div class="doc_text">
190
Chris Lattner591ef272008-10-13 20:47:20 +0000[diff] [blame]191<p>LLVM fully supports the llvm-gcc 4.2 front-end, which marries the GCC
192front-ends and driver with the LLVM optimizer and code generator. It currently
193includes support for the C, C++, Objective-C, Ada, and Fortran front-ends.</p>
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]194
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]195<ul>
Chris Lattner0327f0b2008-10-13 20:59:32 +0000[diff] [blame^]196<li>LLVM 2.4 supports the full set of atomic <tt>__sync_*</tt> builtins. LLVM
1972.3 only supported those used by OpenMP, but 2.4 supports them all. While
198llvm-gcc supports all of these builtins, note that not all targets do. X86 and
199PowerPC are known to support them all in both 32-bit and 64-bit mode.</li>
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]200
Chris Lattner0327f0b2008-10-13 20:59:32 +0000[diff] [blame^]201<li>llvm-gcc now supports an <tt>-flimited-precision</tt> option, which tells
202the compiler that it is ok to use low-precision approximations of certain libm
Chris Lattner591ef272008-10-13 20:47:20 +0000[diff] [blame]203functions (like tan, log, etc). This allows you to get high performance if you
204only need (say) 14-bits of precision.</li>
205
206<li>llvm-gcc now supports a C language extension known as "<a
207href="http://lists.cs.uiuc.edu/pipermail/cfe-dev/2008-August/002670.html">Blocks
208</a>. This feature is similar to nested functions and closures, but does not
209require stack trampolines (with most ABIs) and supports returning closures
210from functions that define them. Note that actually <em>using</em> Blocks
211requires a small runtime that is not included with llvm-gcc.</li>
212
213<li>llvm-gcc now supports a new <tt>-flto</tt> option. On systems that support
214transparent Link Time Optimization (currently Darwin systems with Xcode 3.1 and
215later) this allows the use of LTO with other optimization levels like -Os.
216Previously, LTO could only be used with -O4, which implied optimizations in
217-O3 that can increase code size.</li>
Gabor Greif7f39fb52008-06-09 06:06:18 +0000[diff] [blame]218</ul>
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]219
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]220</div>
221
222
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]223<!--=========================================================================-->
224<div class="doc_subsection">
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]225<a name="coreimprovements">LLVM Core Improvements</a>
226</div>
227
228<div class="doc_text">
229<p>New features include:
230</p>
231
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]232<ul>
Chris Lattner0327f0b2008-10-13 20:59:32 +0000[diff] [blame^]233<li>A major change to the "Use" class landed, which shrank it by 25%. Since
234this is a pervasive part of the LLVM, it ended up reducing the memory use of
235LLVM IR in general by 15% for most programs.</li>
236
237<li>Values with no names are now pretty printed by <tt>llvm-dis</tt> more
238nicely. They now print as "<tt>%3 = add i32 %A, 4</tt>" instead of
239"<tt>add i32 %A, 4 ; &lt;i32&gt;:3</tt>", which makes it much easier to read.
240</li>
241
242<li>LLVM 2.4 includes some changes for better vector support. First, the shift
243operations (<tt>shl</tt>, <tt>ashr</tt>, <tt>lshr</tt>) now all support vectors
244and do an element-by-element shift (shifts of the whole vector can be
245accomplished by bitcasting the vector to &lt;1 x i128&gt; for example). Second,
246there is support in development for vector comparisons. LLVM 2.4 actually
247supports two ways to do vector comparisons: the vicmp/vfcmp instructions and the
248icmp/fcmp instructions. The vicmp/vfcmp instructions are temporary and will be
249removed (do not use them). The icmp/fcmp instructions compare two vectors and
250return a vector of i1's for each result. Note that there is very little codegen
251support available for any of these IR features though.</li>
252
253<li>A new <tt>DebugInfoBuilder</tt> class is available, which makes it much
254easier for front-ends to create debug info descriptors, similar to the way that
255IRBuilder makes it easier to create LLVM IR.</li>
256
257<li>LLVM now supports "function attributes", which allows us to seperate return
258value attributes from function attributes. LLVM now supports attributes on a
259function itself, a return value, and its parameters. New supported function
260attributes include noinline/alwaysinline and the "opt-size" flag which says the
261function should be optimized for code size.</li>
262
Chris Lattner63969522008-10-12 18:30:33 +0000[diff] [blame]263<li>LLVM IR now directly represents "common" linkage, instead of
264 representing it as a form of weak linkage.</li>
Chris Lattner0327f0b2008-10-13 20:59:32 +0000[diff] [blame^]265
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]266</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]267
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]268</div>
269
270<!--=========================================================================-->
271<div class="doc_subsection">
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]272<a name="optimizer">Optimizer Improvements</a>
273</div>
274
275<div class="doc_text">
276
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]277<p>In addition to a huge array of bug fixes and minor performance tweaks, the
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]278LLVM 2.4 optimizers support a few major enhancements:</p>
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]279
280<ul>
281
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]282<li>GVN now does local PRE?</li>
283
284<li>Matthijs' Dead argument elimination rewrite</li>
285
Chris Lattner63969522008-10-12 18:30:33 +0000[diff] [blame]286<li>Old-ADCE used control dependence and deleted output-free infinite loops.
287Added a new Loop deletion pass (for deleting output free provably-finite loops)
288and rewrote ADCE to be simpler faster, and not need control dependence.</li>
289
290<li>SparsePropagation framework for lattice-based dataflow solvers.</li>
291
Chris Lattnere3df07e2008-10-12 22:57:58 +0000[diff] [blame]292<li>Tail duplication was removed from the standard optimizer sequence.</li>
Chris Lattner63969522008-10-12 18:30:33 +0000[diff] [blame]293
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]294<li>Various helper functions (ComputeMaskedBits, ComputeNumSignBits, etc) were
295pulled out of instcombine and put into a new ValueTracking.h file, where they
296can be reused by other passes.</li>
297
Duncan Sands8547c2d2008-10-13 18:42:43 +0000[diff] [blame]298<li>The new AddReadAttrs pass works out which functions are read-only or
299read-none (these correspond to 'pure' and 'const' in C) and marks them
300with the appropriate attribute.</li>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]301</ul>
302
303</div>
304
305<!--=========================================================================-->
306<div class="doc_subsection">
307<a name="codegen">Code Generator Improvements</a>
308</div>
309
310<div class="doc_text">
311
312<p>We put a significant amount of work into the code generator infrastructure,
313which allows us to implement more aggressive algorithms and make it run
314faster:</p>
315
316<ul>
Chris Lattnere3df07e2008-10-12 22:57:58 +0000[diff] [blame]317<li>asm writers split out to their own library to avoid JITs having to link
318 them in.</li>
319<li>Big asm writer refactoring + TargetAsmInfo</li>
320<li>2-addr pass and coalescer can now remat trivial insts to avoid a copy.</li>
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]321<li>spiller to commute instructions in order to fold a reload</li>
322<li>Stack slot coloring?</li>
323<li>Live intervals renumbering? Is this useful to external people?</li>
324<li>'is as cheap as a move' instruction flag</li>
325<li>Improvements to selection dag viewing</li>
326<li>fast isel</li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]327<li>Selection dag speedups</li>
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]328<li>asmwriter + raw_ostream -> fastah</li>
Chris Lattner3fc6e592008-10-13 17:12:51 +0000[diff] [blame]329<li>Partitioned Boolean Quadratic Programming (PBQP) based register
330allocator.</li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]331<li>...</li>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]332
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]333</ul>
334
335</div>
336
337
338<!--=========================================================================-->
339<div class="doc_subsection">
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]340<a name="x86specific">X86/X86-64 Specific Improvements</a>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]341</div>
Chris Lattner727c3742007-05-18 06:33:02 +0000[diff] [blame]342
Chris Lattner89e761c2006-04-18 06:32:08 +0000[diff] [blame]343<div class="doc_text">
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]344<p>New target-specific features include:
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]345</p>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]346
347<ul>
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]348<li>Exception handling is supported by default on Linux/x86-64.</li>
Duncan Sands719f7782008-10-13 17:32:15 +0000[diff] [blame]349<li>Position Independent Code (PIC) is now supported on Linux/x86-64.</li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]350<li>...</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]351
Chris Lattner8ce1ba42007-05-17 21:41:31 +0000[diff] [blame]352</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]353
Chris Lattner8ce1ba42007-05-17 21:41:31 +0000[diff] [blame]354</div>
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]355
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]356<!--=========================================================================-->
357<div class="doc_subsection">
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]358<a name="targetspecific">Other Target Specific Improvements</a>
359</div>
360
361<div class="doc_text">
362<p>New target-specific features include:
363</p>
364
365<ul>
Chris Lattnere3df07e2008-10-12 22:57:58 +0000[diff] [blame]366<li>MIPS floating point support?</li>
Duncan Sands719f7782008-10-13 17:32:15 +0000[diff] [blame]367<li>PowerPC now supports trampolines.</li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]368<li>....</li>
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]369</ul>
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]370
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]371</div>
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]372
373
374<!--=========================================================================-->
375<div class="doc_subsection">
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]376<a name="otherimprovements">Other Improvements</a>
377</div>
378
379<div class="doc_text">
380<p>New features include:
381</p>
382
383<ul>
Mikhail Glushenkovd3ec89e2008-10-13 02:46:01 +0000[diff] [blame]384<li><tt>llvmc2</tt> (the generic compiler driver) gained plugin
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]385 support. It is now easier to experiment with <tt>llvmc2</tt> and
386 build your own tools based on it. </li>
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]387<li>raw_ostream + formatting</li>
Chris Lattnere3df07e2008-10-12 22:57:58 +0000[diff] [blame]388<li>Recycler + pool allocation stuff?</li>
Chris Lattnerd8b33e02008-10-11 18:18:28 +0000[diff] [blame]389<li>...</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]390</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]391
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]392</div>
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]393
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]394<!--=========================================================================-->
395<div class="doc_subsection">
396<a name="changes">Major Changes and Removed Features</a>
397</div>
398
399<div class="doc_text">
400
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]401<p>If you're already an LLVM user, this section lists some "gotchas" that you
402may run into upgrading from the previous release.</p>
403
Duncan Sandsb34d5902008-10-13 18:33:28 +0000[diff] [blame]404<p>The LLVM IR generated by llvm-gcc no longer names all instructions.
405 Use the instnamer pass if you want everything named.</p>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]406
Duncan Sandsb34d5902008-10-13 18:33:28 +0000[diff] [blame]407<li>The LoadVN and GCSE passes have been removed.</li>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]408
409
410<p>LLVM API Changes:</p>
411
412<ul>
413
414<li>... Attributes changes ... </li>
415
416<li>The <tt>DbgStopPointInst</tt> methods <tt>getDirectory</tt> and
417<tt>getFileName</tt> now return <tt>Value*</tt> instead of strings. These can be
418converted to strings using <tt>llvm::GetConstantStringInfo</tt> defined via
419"llvm/Analysis/ValueTracking.h".</li>
420
421<li>API change: BinaryOperator::create -> Create (CmpInst, CastInst too)</li>
422<li>Various header files like "llvm/ADT/iterator" were given a .h suffix.
423 Change your code to #include "llvm/ADT/iterator.h" instead.</li>
424
425</ul>
426
427</div>
428
429
430
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]431<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]432<div class="doc_section">
433 <a name="portability">Portability and Supported Platforms</a>
434</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]435<!-- *********************************************************************** -->
436
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]437<div class="doc_text">
438
John Criswell64307722004-12-08 20:35:47 +0000[diff] [blame]439<p>LLVM is known to work on the following platforms:</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]440
441<ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]442<li>Intel and AMD machines (IA32) running Red Hat Linux, Fedora Core and FreeBSD
Reid Spencer9803b402005-05-17 02:47:27 +0000[diff] [blame]443 (and probably other unix-like systems).</li>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]444<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit and
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]445 64-bit modes.</li>
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]446<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]447<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
448 support is available for native builds with Visual C++).</li>
Gabor Greif80ae8a72008-06-05 18:39:01 +0000[diff] [blame]449<li>Sun UltraSPARC workstations running Solaris 10.</li>
John Criswelld5234922005-05-13 20:28:15 +0000[diff] [blame]450<li>Alpha-based machines running Debian GNU/Linux.</li>
Gabor Greif80ae8a72008-06-05 18:39:01 +0000[diff] [blame]451<li>Itanium-based (IA64) machines running Linux and HP-UX.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]452</ul>
453
Chris Lattner618a99f2008-06-05 06:57:39 +0000[diff] [blame]454<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]455to the machine and operating system on which it is built. However, minor
456porting may be required to get LLVM to work on new platforms. We welcome your
457portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]458
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]459</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]460
461<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462<div class="doc_section">
463 <a name="knownproblems">Known Problems</a>
464</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]465<!-- *********************************************************************** -->
466
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]467<div class="doc_text">
468
469<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]470component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]471sections. If you run into a problem, please check the <a
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]472href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]473there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]474
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]475</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]476
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]477<!-- ======================================================================= -->
478<div class="doc_subsection">
479 <a name="experimental">Experimental features included with this release</a>
480</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]481
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]482<div class="doc_text">
483
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]484<p>The following components of this LLVM release are either untested, known to
485be broken or unreliable, or are in early development. These components should
486not be relied on, and bugs should not be filed against them, but they may be
487useful to some people. In particular, if you would like to work on one of these
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]488components, please contact us on the <a
489href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]490
491<ul>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]492<li>The MSIL, IA64, Alpha, SPU, and MIPS backends are experimental.</li>
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]493<li>The llc "<tt>-filetype=asm</tt>" (the default) is the only supported
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]494 value for this option.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]495</ul>
496
497</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]498
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]499<!-- ======================================================================= -->
500<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]501 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]502</div>
503
504<div class="doc_text">
505
506<ul>
Anton Korobeynikov486c7d32008-06-08 10:24:13 +0000[diff] [blame]507 <li>The X86 backend does not yet support
508 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
509 floating point stack</a>. It supports the 'f' and 't' constraints, but not
510 'u'.</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]511 <li>The X86 backend generates inefficient floating point code when configured
512 to generate code for systems that don't have SSE2.</li>
Duncan Sands0bc15262008-06-08 19:38:43 +0000[diff] [blame]513 <li>Win64 code generation wasn't widely tested. Everything should work, but we
Anton Korobeynikov486c7d32008-06-08 10:24:13 +0000[diff] [blame]514 expect small issues to happen. Also, llvm-gcc cannot build mingw64 runtime
515 currently due
516 to <a href="http://llvm.org/PR2255">several</a>
Chris Lattner54d12102008-06-08 23:12:47 +0000[diff] [blame]517 <a href="http://llvm.org/PR2257">bugs</a> due to lack of support for the
518 'u' inline assembly constraint and X87 floating point inline assembly.</li>
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]519 <li>The X86-64 backend does not yet support the LLVM IR instruction
520 <tt>va_arg</tt>. Currently, the llvm-gcc front-end supports variadic
521 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]522</ul>
523
524</div>
525
526<!-- ======================================================================= -->
527<div class="doc_subsection">
528 <a name="ppc-be">Known problems with the PowerPC back-end</a>
529</div>
530
531<div class="doc_text">
532
533<ul>
Nicolas Geoffray77d99502007-05-15 09:21:28 +0000[diff] [blame]534<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]535compilation, and lacks support for debug information.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]536</ul>
537
538</div>
539
540<!-- ======================================================================= -->
541<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]542 <a name="arm-be">Known problems with the ARM back-end</a>
543</div>
544
545<div class="doc_text">
546
547<ul>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]548<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]549processors, thumb programs can crash or produce wrong
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]550results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]551<li>Compilation for ARM Linux OABI (old ABI) is supported, but not fully tested.
552</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]553<li>There is a bug in QEMU-ARM (&lt;= 0.9.0) which causes it to incorrectly
554 execute
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]555programs compiled with LLVM. Please use more recent versions of QEMU.</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]556</ul>
557
558</div>
559
560<!-- ======================================================================= -->
561<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]562 <a name="sparc-be">Known problems with the SPARC back-end</a>
563</div>
564
565<div class="doc_text">
566
567<ul>
568<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32), it does not
569 support the 64-bit SPARC ABI (-m64).</li>
570</ul>
571
572</div>
573
574<!-- ======================================================================= -->
575<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]576 <a name="alpha-be">Known problems with the Alpha back-end</a>
577</div>
578
579<div class="doc_text">
580
581<ul>
582
583<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
584appropriate nops inserted to ensure restartability.</li>
585
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]586</ul>
587</div>
588
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]589<!-- ======================================================================= -->
590<div class="doc_subsection">
591 <a name="ia64-be">Known problems with the IA64 back-end</a>
592</div>
593
594<div class="doc_text">
595
596<ul>
Chris Lattner54d12102008-06-08 23:12:47 +0000[diff] [blame]597<li>The Itanium backend is highly experimental, and has a number of known
598 issues. We are looking for a maintainer for the Itanium backend. If you
599 are interested, please contact the llvmdev mailing list.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]600</ul>
601
602</div>
603
604<!-- ======================================================================= -->
605<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]606 <a name="c-be">Known problems with the C back-end</a>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]607</div>
608
609<div class="doc_text">
610
611<ul>
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]612<li><a href="http://llvm.org/PR802">The C backend has only basic support for
613 inline assembly code</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]614<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
615 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]616 C++ code compiled with llc or native compilers.</li>
Duncan Sandse09506a2008-02-10 13:40:55 +0000[diff] [blame]617<li>The C backend does not support all exception handling constructs.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]618</ul>
619
620</div>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]621
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]622
623<!-- ======================================================================= -->
624<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]625 <a name="c-fe">Known problems with the llvm-gcc C front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]626</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]627
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]628<div class="doc_text">
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]629
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]630<p>llvm-gcc does not currently support <a href="http://llvm.org/PR869">Link-Time
631Optimization</a> on most platforms "out-of-the-box". Please inquire on the
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]632llvmdev mailing list if you are interested.</p>
Chris Lattner44124232006-08-08 17:27:28 +0000[diff] [blame]633
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]634<p>The only major language feature of GCC not supported by llvm-gcc is
635 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
636 are only supported on some targets. For example, trampolines are only
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]637 supported on some targets (these are used when you take the address of a
638 nested function).</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]639
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]640<p>If you run into GCC extensions which are not supported, please let us know.
641</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]642
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]643</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]644
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]645<!-- ======================================================================= -->
646<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]647 <a name="c++-fe">Known problems with the llvm-gcc C++ front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]648</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]649
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]650<div class="doc_text">
651
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]652<p>The C++ front-end is considered to be fully
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]653tested and works for a number of non-trivial programs, including LLVM
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]654itself, Qt, Mozilla, etc.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]655
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]656<ul>
Anton Korobeynikov28f08aa2008-10-11 18:27:16 +0000[diff] [blame]657<li>Exception handling works well on the X86 and PowerPC targets. Currently
658 only linux and darwin targets are supported (both 32 and 64 bit).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]659</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]660
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]661</div>
662
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]663
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]664<!-- ======================================================================= -->
665<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]666 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]667</div>
668
669<div class="doc_text">
670The llvm-gcc 4.2 Ada compiler works fairly well, however this is not a mature
671technology and problems should be expected.
672<ul>
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]673<li>The Ada front-end currently only builds on X86-32. This is mainly due
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]674to lack of trampoline support (pointers to nested functions) on other platforms,
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]675however it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]676which does support trampolines.</li>
677<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
678Workaround: configure with --disable-bootstrap.</li>
Duncan Sandsaef747f2008-10-13 17:27:23 +0000[diff] [blame]679<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
680and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
681(c380004 also fails with gcc-4.2 mainline).</li>
682<li>Some gcc specific Ada tests continue to crash the compiler.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]683<li>The -E binder option (exception backtraces)
684<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
685crashing if an exception is raised. Workaround: do not use -E.</li>
686<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
687or finish at a non-byte offset</a> in a record. Workaround: do not pack records
688or use representation clauses that result in a field of a non-discrete type
689starting or finishing in the middle of a byte.</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]690<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
691'main' as generated by the Ada binder to be invalid</a>.
692Workaround: hand edit the file to use pointers for <tt>argv</tt> and
693<tt>envp</tt> rather than integers.</li>
694<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
695ignored</a>.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]696</ul>
697</div>
698
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]699<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]700<div class="doc_section">
701 <a name="additionalinfo">Additional Information</a>
702</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]703<!-- *********************************************************************** -->
704
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]705<div class="doc_text">
706
Chris Lattnercb5596d2005-05-16 17:13:10 +0000[diff] [blame]707<p>A wide variety of additional information is available on the <a
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]708href="http://llvm.org">LLVM web page</a>, in particular in the <a
709href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencerc7f87f22007-07-09 08:04:31 +0000[diff] [blame]710contains versions of the API documentation which is up-to-date with the
711Subversion version of the source code.
Misha Brukman96158092005-03-30 19:14:24 +0000[diff] [blame]712You can access versions of these documents specific to this release by going
713into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]714
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]715<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]716us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]717lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]718
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]719</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]720
721<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]722
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]723<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]724<address>
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