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diff --git a/share/doc/gccint/Gimplification-pass.html b/share/doc/gccint/Gimplification-pass.html new file mode 100644 index 0000000..97a6f4f --- /dev/null +++ b/share/doc/gccint/Gimplification-pass.html @@ -0,0 +1,125 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). 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The term stuck, and so words like “gimplification”, +“gimplify”, “gimplifier” and the like are sprinkled throughout this +section of code. +</p> +<p>While a front end may certainly choose to generate GIMPLE directly if +it chooses, this can be a moderately complex process unless the +intermediate language used by the front end is already fairly simple. +Usually it is easier to generate GENERIC trees plus extensions +and let the language-independent gimplifier do most of the work. +</p> +<a name="index-gimplify_005ffunction_005ftree"></a> +<a name="index-gimplify_005fexpr"></a> +<a name="index-lang_005fhooks_002egimplify_005fexpr"></a> +<p>The main entry point to this pass is <code>gimplify_function_tree</code> +located in <samp>gimplify.cc</samp>. From here we process the entire +function gimplifying each statement in turn. The main workhorse +for this pass is <code>gimplify_expr</code>. Approximately everything +passes through here at least once, and it is from here that we +invoke the <code>lang_hooks.gimplify_expr</code> callback. +</p> +<p>The callback should examine the expression in question and return +<code>GS_UNHANDLED</code> if the expression is not a language specific +construct that requires attention. Otherwise it should alter the +expression in some way to such that forward progress is made toward +producing valid GIMPLE. If the callback is certain that the +transformation is complete and the expression is valid GIMPLE, it +should return <code>GS_ALL_DONE</code>. Otherwise it should return +<code>GS_OK</code>, which will cause the expression to be processed again. +If the callback encounters an error during the transformation (because +the front end is relying on the gimplification process to finish +semantic checks), it should return <code>GS_ERROR</code>. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Pass-manager.html#Pass-manager" accesskey="n" rel="next">Pass manager</a>, Previous: <a href="Parsing-pass.html#Parsing-pass" accesskey="p" rel="previous">Parsing pass</a>, Up: <a href="Passes.html#Passes" accesskey="u" rel="up">Passes</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |