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| author | Chris Lattner <sabre@nondot.org> | 2005-02-28 19:24:19 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2005-02-28 19:24:19 +0000 |
| commit | c8a2c22f3655068e3bff58b42ad4102caa62dd89 (patch) | |
| tree | 9be965ec88d1d75369a45572fd0166285c023baa | |
| parent | 76eff4819526437344cc239c5c36f3ba8347d616 (diff) | |
| download | llvm-c8a2c22f3655068e3bff58b42ad4102caa62dd89.zip llvm-c8a2c22f3655068e3bff58b42ad4102caa62dd89.tar.gz llvm-c8a2c22f3655068e3bff58b42ad4102caa62dd89.tar.bz2 | |
Document llvm.prefetch, patch contributed by Justin Wick!
llvm-svn: 20373
| -rw-r--r-- | llvm/docs/LangRef.html | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/llvm/docs/LangRef.html b/llvm/docs/LangRef.html index 88cf2a6..38229f5 100644 --- a/llvm/docs/LangRef.html +++ b/llvm/docs/LangRef.html @@ -125,6 +125,7 @@ <ol> <li><a href="#i_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li> <li><a href="#i_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a></li> + <li><a href="#i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a></li> </ol> </li> <li><a href="#int_os">Operating System Intrinsics</a> @@ -2499,6 +2500,52 @@ source-language caller. </p> </div> +<!-- _______________________________________________________________________ --> +<div class="doc_subsubsection"> + <a name="i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a> +</div> + +<div class="doc_text"> + +<h5>Syntax:</h5> +<pre> + call void (sbyte *, uint, uint)* %llvm.prefetch(sbyte * <address>, + uint <rw>, + uint <locality>) +</pre> + +<h5>Overview:</h5> + + +<p> +The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert +a prefetch instruction if supported, otherwise it is a noop. Prefetches have no +behavior affect on the program, but can change the performance characteristics +of the code. +</p> + +<h5>Arguments:</h5> + +<p> +<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier +determining if the fetch should be for a read (0) or write (1), and +<tt>locality</tt> is a temporal locality specifier ranging from (0) - no +locality, to (3) - exteremely local keep in cache. The <tt>rw</tt> and +<tt>locality</tt> arguments must be constant integers. +</p> + +<h5>Semantics:</h5> + +<p> +This intrinsic does not modify the behavior of the program. In particular, +prefetches cannot trap and do not produce a value. On targets that support this +intrinsic, the prefetch can provide hints to the processor cache for better +performance. +</p> + +</div> + + <!-- ======================================================================= --> <div class="doc_subsection"> <a name="int_os">Operating System Intrinsics</a> |