-<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>
-</div>
-
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-<div class="doc_subsection">
- <a name="basicaa">Basic Alias Analysis (default AA impl)</a>
-</div>
-<div class="doc_text">