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diff --git a/docs/Passes.html b/docs/Passes.html index c366808c1d..a0b233711b 100644 --- a/docs/Passes.html +++ b/docs/Passes.html @@ -75,7 +75,6 @@ perl -e '$/ = undef; for (split(/\n/, <>)) { s:^ *///? ?::; print " <p>\n" if ! <tr><th colspan="2"><b>ANALYSIS PASSES</b></th></tr> <tr><th>Option</th><th>Name</th></tr> <tr><td><a href="#aa-eval">-aa-eval</a></td><td>Exhaustive Alias Analysis Precision Evaluator</td></tr> -<tr><td><a href="#anders-aa">-anders-aa</a></td><td>Andersen's Interprocedural Alias Analysis</td></tr> <tr><td><a href="#basicaa">-basicaa</a></td><td>Basic Alias Analysis (default AA impl)</td></tr> <tr><td><a href="#basiccg">-basiccg</a></td><td>Basic CallGraph Construction</td></tr> <tr><td><a href="#codegenprepare">-codegenprepare</a></td><td>Optimize for code generation</td></tr> @@ -204,80 +203,6 @@ perl -e '$/ = undef; for (split(/\n/, <>)) { s:^ *///? ?::; print " <p>\n" if ! <!-------------------------------------------------------------------------- --> <div class="doc_subsection"> - <a name="anders-aa">Andersen's Interprocedural Alias Analysis</a> -</div> -<div class="doc_text"> - <p> - This is an implementation of Andersen's interprocedural alias - analysis - </p> - - <p> - In pointer analysis terms, this is a subset-based, flow-insensitive, - field-sensitive, and context-insensitive algorithm pointer algorithm. - </p> - - <p> - This algorithm is implemented as three stages: - </p> - - <ol> - <li>Object identification.</li> - <li>Inclusion constraint identification.</li> - <li>Offline constraint graph optimization.</li> - <li>Inclusion constraint solving.</li> - </ol> - - <p> - The object identification stage identifies all of the memory objects in the - program, which includes globals, heap allocated objects, and stack allocated - objects. - </p> - - <p> - The inclusion constraint identification stage finds all inclusion constraints - in the program by scanning the program, looking for pointer assignments and - other statements that effect the points-to graph. For a statement like - <code><var>A</var> = <var>B</var></code>, this statement is processed to - indicate that <var>A</var> can point to anything that <var>B</var> can point - to. Constraints can handle copies, loads, and stores, and address taking. - </p> - - <p> - The offline constraint graph optimization portion includes offline variable - substitution algorithms intended to computer pointer and location - equivalences. Pointer equivalences are those pointers that will have the - same points-to sets, and location equivalences are those variables that - always appear together in points-to sets. - </p> - - <p> - The inclusion constraint solving phase iteratively propagates the inclusion - constraints until a fixed point is reached. This is an O(<var>n</var>³) - algorithm. - </p> - - <p> - Function constraints are handled as if they were structs with <var>X</var> - fields. Thus, an access to argument <var>X</var> of function <var>Y</var> is - an access to node index <code>getNode(<var>Y</var>) + <var>X</var></code>. - This representation allows handling of indirect calls without any issues. To - wit, an indirect call <code><var>Y</var>(<var>a</var>,<var>b</var>)</code> is - equivalent to <code>*(<var>Y</var> + 1) = <var>a</var>, *(<var>Y</var> + 2) = - <var>b</var></code>. The return node for a function <var>F</var> is always - located at <code>getNode(<var>F</var>) + CallReturnPos</code>. The arguments - start at <code>getNode(<var>F</var>) + CallArgPos</code>. - </p> - - <p> - Please keep in mind that the current andersen's pass has many known - problems and bugs. It should be considered "research quality". - </p> - -</div> - -<!-------------------------------------------------------------------------- --> -<div class="doc_subsection"> <a name="basicaa">Basic Alias Analysis (default AA impl)</a> </div> <div class="doc_text"> @@ -1848,7 +1773,7 @@ if (X < 3) {</pre> <a href="mailto:rspencer@x10sys.com">Reid Spencer</a><br> <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br> - Last modified: $Date: 2009-10-27 21:47:06 -0700 (Tue, 27 Oct 2009) $ + Last modified: $Date: 2010-03-02 03:24:17 +0800 (二, 02 3月 2010) $ </address> </body> |