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author | Chris Lattner <sabre@nondot.org> | 2005-05-16 16:56:09 +0000 |
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committer | Chris Lattner <sabre@nondot.org> | 2005-05-16 16:56:09 +0000 |
commit | bf307010c5e0c7da519039aa46ab95c0b981f97a (patch) | |
tree | 9f04aa680849f2e4c662ae907eec07c3048fa06c /docs | |
parent | 775afa5ec028df7a2b64c29787cb04d907ba13c0 (diff) | |
download | external_llvm-bf307010c5e0c7da519039aa46ab95c0b981f97a.zip external_llvm-bf307010c5e0c7da519039aa46ab95c0b981f97a.tar.gz external_llvm-bf307010c5e0c7da519039aa46ab95c0b981f97a.tar.bz2 |
more edits, include stuff from the status update
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22086 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs')
-rw-r--r-- | docs/ReleaseNotes.html | 86 |
1 files changed, 62 insertions, 24 deletions
diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index 9c0824f..99d7209 100644 --- a/docs/ReleaseNotes.html +++ b/docs/ReleaseNotes.html @@ -62,10 +62,9 @@ href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p> <p>This is the sixth public release of the LLVM Compiler Infrastructure.</p> -<p> At this time, LLVM is known to correctly compile a wide range of C and C++ -programs, including the SPEC CPU95 & 2000 suite. It includes bug fixes for -those problems found since the 1.4 release and a large number of new features -and enhancements, described below.</p> +<p>LLVM 1.5 is known to correctly compile a wide range of C and C++ programs, +includes bug fixes for those problems found since the 1.4 release, and includes +a large number of new features and enhancements, described below.</p> </div> @@ -101,7 +100,7 @@ easy to get wrong) details of writing the instruction selector, such as generating efficient code for <a href="LangRef.html#i_getelementptr">getelementptr</a> instructions, promoting small integer types to larger types (e.g. for RISC targets with one size of -integer registers), expanding 64-bit integer operations for 32-bit hosts, etc. +integer registers), expanding 64-bit integer operations for 32-bit targets, etc. Currently, the X86, PowerPC, Alpha, and IA-64 backends use this framework. The SPARC backends will be migrated when time permits. </p> @@ -138,7 +137,7 @@ Proper Tail Calls</a></div> href="http://doi.acm.org/10.1145/277650.277719">proper tail calls</a>, as required to implement languages like Scheme. Tail calls make use of two features: custom calling conventions (described above), which allow the code -generator to emit code for the caller to deallocate its own stack when it +generator to use a convention where the caller deallocates its stack before it returns. The second feature is a flag on the <a href="LangRef.html#i_call">call instruction</a>, which indicates that the callee does not access the caller's stack frame (indicating that it is acceptable to deallocate the caller stack @@ -149,11 +148,11 @@ than the caller, etc. The only case not supported are varargs calls, but that could be added if desired. </p> -<p>In order for a front-end to get guaranteed tail call, it must mark functions -as "fastcc", mark calls with the 'tail' marker, and follow the call with a -return of the called value (or void). The optimizer and code generator attempt -to handle more general cases, but the simple case will always work if the code -generator supports tail calls. Here is a simple example:</p> +<p>In order for a front-end to get a guaranteed tail call, it must mark +functions as "fastcc", mark calls with the 'tail' marker, and follow the call +with a return of the called value (or void). The optimizer and code generator +attempt to handle more general cases, but the simple case will always work if +the code generator supports tail calls. Here is an example:</p> <pre> fastcc int %bar(int %X, int(double, int)* %FP) { ;<i> fastcc</i> @@ -198,7 +197,8 @@ multiple of 8 bytes in size. <li>LLVM 1.5 is now about 15% faster than LLVM 1.4 and its core data structures use about 30% less memory.</li> <li>Support for Microsoft Visual Studio is improved, and <a - href="GettingStartedVS.html">now documented</a>.</li> + href="GettingStartedVS.html">now documented</a>. Most LLVM tools build + natively with Visual C++ now.</li> <li><a href="GettingStarted.html#config">Configuring LLVM to build a subset of the available targets</a> is now implemented, via the <tt>--enable-targets=</tt> option.</li> @@ -215,7 +215,13 @@ multiple of 8 bytes in size. <li>LLVM now includes workarounds in the code generator generator which reduces the likelyhood of <a href="http://llvm.cs.uiuc.edu/PR448">GCC hitting swap during optimized builds</a>.</li> - <li>The PowerPC backend generates far better code than in LLVM 1.4.</li> + <li>The <a href="http://llvm.cs.uiuc.edu/ProjectsWithLLVM/#llvmtv">LLVM + Transformation Visualizer</a> (llvm-tv) project has been updated to + work with LLVM CVS.</li> + <li>Nightly tester output is now archived on the <a + href="http://mail.cs.uiuc.edu/pipermail/llvm-testresults/"> + llvm-testresults</a> mailing list.</li> + </ol> </div> @@ -226,31 +232,62 @@ multiple of 8 bytes in size. <div class="doc_text"> <ol> -<li>The -globalopt pass now promotes non-address-taken static globals that are -only accessed in main to SSA registers.</li> - <li>The new -simplify-libcalls pass improves code generated for well-known library calls. The pass optimizes calls to many of the string, memory, and standard I/O functions (e.g. replace the calls with simpler/faster calls) when possible, given information known statically about the arguments to the call. </li> +<li>The -globalopt pass now promotes non-address-taken static globals that are +only accessed in main to SSA registers.</li> + <li>Loops with trip counts based on array pointer comparisons (e.g. "<tt>for (i -= 0; &A[i] != &A[100]; ++i) ...</tt>") are optimized better than before, += 0; &A[i] != &A[n]; ++i) ...</tt>") are optimized better than before, which primarily helps iterator-intensive C++ codes.</li> -<li>The code generator now can provide and use information about commutative -two-address instructions when performing register allocation.</li> - <li>The optimizer now eliminates simple cases where redundant conditions exist -between neighboring blocks.</li> + between neighboring blocks.</li> <li>The reassociation pass (which turns (1+X+3) into (X+1+3) among other -things), is more aggressive an intelligent.</li> - +things), is more aggressive and intelligent.</li> + +<li>The -prune-eh pass now detects no-return functions in addition to the + no-unwind functions it did before.</li> + +<li>The -globalsmodref alias analysis generates more precise results in some + cases.</li> +</ol> +</div> + + +<!--=========================================================================--> +<div class="doc_subsection"> +<a name="codequality">Code Generator Improvements in LLVM 1.5</a> +</div> + +<div class="doc_text"> +<ol> +<li>The code generator now can provide and use information about commutative + two-address instructions when performing register allocation.</li> + +<li>The code generator now tracks function live-in registers explicitly, + instead of requiring the target to generate 'implicit defs' at the + entry to a function.</li> + +<li>The code generator can lower integer division by a constant to + multiplication by a magic constant and multiplication by a constant into + shift/add sequences.</li> + +<li>The code generator compiles fabs/fneg/sin/cos/sqrt to assembly instructions + when possible.</li> + +<li>The PowerPC backend generates better code in many cases, making use of + FMA instructions and the recording ("dot") forms of various PowerPC + instructions.</li> </ol> </div> + <!--=========================================================================--> <div class="doc_subsection"> <a name="bugfix">Significant Bugs Fixed in LLVM 1.5</a> @@ -266,7 +303,7 @@ things), is more aggressive an intelligent.</li> <li><a href="http://llvm.cs.uiuc.edu/PR548">[instcombine] miscompilation of setcc or setcc in one case</a></li> <li>Transition code for LLVM 1.0 style varargs was removed from the .ll file - parser. LLVM 1.0 bytecode files are still supported. </li> + parser. LLVM 1.0 bytecode files are still supported. </li> </ol> <p>Code Generator Bugs:</p> @@ -277,6 +314,7 @@ things), is more aggressive an intelligent.</li> respect 'volatile'</a>.</li> <li>The JIT sometimes miscompiled globals and constant pool entries for 64-bit integer constants on 32-bit hosts.</li> + <li>The C backend should no longer produce code that crashes ICC 8.1.</li> </ol> <p>Bugs in the C/C++ front-end:</p> |