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<a name="Match-and-Simplify-1"></a>
<h2 class="chapter">26 Match and Simplify</h2>
<a name="index-Match-and-Simplify"></a>

<p>The GIMPLE and GENERIC pattern matching project match-and-simplify
tries to address several issues.
</p>
<ol>
<li> unify expression simplifications currently spread and duplicated
    over separate files like fold-const.c, gimple-fold.c and builtins.c
</li><li> allow for a cheap way to implement building and simplifying
    non-trivial GIMPLE expressions, avoiding the need to go through
    building and simplifying GENERIC via fold_buildN and then
    gimplifying via force_gimple_operand
</li></ol>

<p>To address these the project introduces a simple domain specific language
to write expression simplifications from which code targeting GIMPLE
and GENERIC is auto-generated.  The GENERIC variant follows the
fold_buildN API while for the GIMPLE variant and to address 2) new
APIs are introduced.
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