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diff --git a/third_party/java/proguard/proguard5.3.3/docs/manual/optimizations.html b/third_party/java/proguard/proguard5.3.3/docs/manual/optimizations.html new file mode 100644 index 0000000000..09270e2ca5 --- /dev/null +++ b/third_party/java/proguard/proguard5.3.3/docs/manual/optimizations.html @@ -0,0 +1,202 @@ +<!doctype html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> +<meta http-equiv="content-type" content="text/html; charset=iso-8859-1"> +<meta http-equiv="content-style-type" content="text/css"> +<link rel="stylesheet" type="text/css" href="style.css"> +<title>Optimizations</title> +</head> +<body> + +<script type="text/javascript" language="JavaScript"> +<!-- +if (window.self==window.top) + document.write('<a class="largebutton" target="_top" href="../index.html#manual/optimizations.html">ProGuard index</a> <a class="largebutton" target="_top" href="http://www.guardsquare.com/dexguard">DexGuard</a> <a class="largebutton" target="_top" href="http://www.guardsquare.com/">GuardSquare</a> <a class="largebutton" target="other" href="http://sourceforge.net/projects/proguard/">Sourceforge</a>') +//--> +</script> +<noscript> +<a class="largebutton" target="_top" href="../index.html#manual/optimizations.html">ProGuard index</a> +<a class="largebutton" target="_top" href="http://www.guardsquare.com/dexguard">DexGuard</a> +<a class="largebutton" target="_top" href="http://www.guardsquare.com/">GuardSquare</a> +<a class="largebutton" target="other" href="http://sourceforge.net/projects/proguard/">Sourceforge</a> +</noscript> + +<h2>Optimizations</h2> + +The optimization step of ProGuard can be switched off with the +<a href="usage.html#dontoptimize"><code>-dontoptimize</code></a> option. For +more fine-grained control over individual optimizations, experts can use the +<a href="usage.html#optimizations"><code>-optimizations</code></a> option, +with a filter based on the optimization names listed below. The filter works +like any <a href="usage.html#filters">filter</a> in ProGuard. +<p> + +The following wildcards are supported: + +<table cellspacing="10"> +<tr><td valign="top"><code><b>?</b></code></td> + <td>matches any single character in an optimization name.</td></tr> +<tr><td valign="top"><code><b>*</b></code></td> + <td>matches any part of an optimization name.</td></tr> +</table> + +An optimization that is preceded by an exclamation mark '<b>!</b>' is +<i>excluded</i> from further attempts to match with <i>subsequent</i> +optimization names in the filter. Make sure to specify filters correctly, +since they are not checked for potential typos. +<p> + +For example, +"<code>code/simplification/variable,code/simplification/arithmetic</code>" +only performs the two specified peephole optimizations. +<p> + +For example, "<code>!method/propagation/*</code>" performs all optimizations, +except the ones that propagate values between methods. +<p> + +For example, +"<code>!code/simplification/advanced,code/simplification/*</code>" only +performs all peephole optimizations. +<p> +Some optimizations necessarily imply other optimizations. These are then +indicated. Note that the list is likely to change over time, as optimizations +are added and reorganized. +<p> + +<dl> +<dt><code><b>class/marking/final</b></code></dt> +<dd>Marks classes as final, whenever possible.</dd> + +<dt><code><b>class/unboxing/enum</b></code></dt> +<dd>Simplifies enum types to integer constants, whenever possible.</dd> + +<dt><code><b>class/merging/vertical</b></code></dt> +<dd>Merges classes vertically in the class hierarchy, whenever possible.</dd> + +<dt><code><b>class/merging/horizontal</b></code></dt> +<dd>Merges classes horizontally in the class hierarchy, whenever possible.</dd> + +<dt><div>(⇒ <code>code/removal/advanced</code>)</div> + <code><b>field/removal/writeonly</b></code></dt> +<dd>Removes write-only fields.</dd> + +<dt><code><b>field/marking/private</b></code></dt> +<dd>Marks fields as private, whenever possible.</dd> + +<dt><div>(⇒ <code>code/simplification/advanced</code>)</div> + <code><b>field/propagation/value</b></code></dt> +<dd>Propagates the values of fields across methods.</dd> + +<dt><code><b>method/marking/private</b></code></dt> +<dd>Marks methods as private, whenever possible (<i>devirtualization</i>).</dd> + +<dt><div>(⇒ <code>code/removal/advanced</code>)</div> + <code><b>method/marking/static</b></code></dt> +<dd>Marks methods as static, whenever possible (<i>devirtualization</i>).</dd> + +<dt><code><b>method/marking/final</b></code></dt> +<dd>Marks methods as final, whenever possible.</dd> + +<dt><div>(⇒ <code>code/removal/advanced</code>)</div> + <code><b>method/removal/parameter</b></code></dt> +<dd>Removes unused method parameters.</dd> + +<dt><div>(⇒ <code>code/simplification/advanced</code>)</div> + <code><b>method/propagation/parameter</b></code></dt> +<dd>Propagates the values of method parameters from method invocations to + the invoked methods.</dd> + +<dt><div>(⇒ <code>code/simplification/advanced</code>)</div> + <code><b>method/propagation/returnvalue</b></code></dt> +<dd>Propagates the values of method return values from methods to their + invocations.</dd> + +<dt><code><b>method/inlining/short</b></code></dt> +<dd>Inlines short methods.</dd> + +<dt><code><b>method/inlining/unique</b></code></dt> +<dd>Inlines methods that are only called once.</dd> + +<dt><code><b>method/inlining/tailrecursion</b></code></dt> +<dd>Simplifies tail recursion calls, whenever possible.</dd> + +<dt><code><b>code/merging</b></code></dt> +<dd>Merges identical blocks of code by modifying branch targets.</dd> + +<dt><code><b>code/simplification/variable</b></code></dt> +<dd>Performs peephole optimizations for variable loading and storing.</dd> + +<dt><code><b>code/simplification/arithmetic</b></code></dt> +<dd>Performs peephole optimizations for arithmetic instructions.</dd> + +<dt><code><b>code/simplification/cast</b></code></dt> +<dd>Performs peephole optimizations for casting operations.</dd> + +<dt><code><b>code/simplification/field</b></code></dt> +<dd>Performs peephole optimizations for field loading and storing.</dd> + +<dt><div>(⇒ <code>code/removal/simple</code>)</div> + <code><b>code/simplification/branch</b></code></dt> +<dd>Performs peephole optimizations for branch instructions.</dd> + +<dt><code><b>code/simplification/string</b></code></dt> +<dd>Performs peephole optimizations for constant strings.</dd> + +<dt><div>(<i>best used with</i> <code>code/removal/advanced</code>)</div> + <code><b>code/simplification/advanced</b></code></dt> +<dd>Simplifies code based on control flow analysis and data flow + analysis.</dd> + +<dt><div>(⇒ <code>code/removal/exception</code>)</div> + <code><b>code/removal/advanced</b></code></dt> +<dd>Removes dead code based on control flow analysis and data flow + analysis.</dd> + +<dt><div>(⇒ <code>code/removal/exception</code>)</div> + <code><b>code/removal/simple</b></code></dt> +<dd>Removes dead code based on a simple control flow analysis.</dd> + +<dt><code><b>code/removal/variable</b></code></dt> +<dd>Removes unused variables from the local variable frame.</dd> + +<dt><code><b>code/removal/exception</b></code></dt> +<dd>Removes exceptions with empty try blocks.</dd> + +<dt><code><b>code/allocation/variable</b></code></dt> +<dd>Optimizes variable allocation on the local variable frame.</dd> +</dl> +<p> + +ProGuard also provides some unofficial settings to control optimizations, that +may disappear in future versions. These are Java system properties, which +can be set as JVM arguments (with <code>-D.....)</code>: +<dl> +<dt><code><b>maximum.inlined.code.length</b></code> (default = 8 bytes)</dt> +<dd>Specifies the maximum code length (expressed in bytes) of short methods + that are eligible to be inlined. Inlining methods that are too long may + unnecessarily inflate the code size.</dd> + +<dt><code><b>maximum.resulting.code.length</b></code> (default = 8000 bytes + for JSE, 2000 bytes for JME)</dt> +<dd>Specifies the maximum resulting code length (expressed in bytes) allowed + when inlining methods. Many Java virtual machines do not apply just-in-time + compilation to methods that are too long, so it's important not to let them + grow too large.</dd> + +<dt><code><b>optimize.conservatively</b></code> (default = unset)</dt> +<dd>Allows input code with ordinary instructions intentionally throwing + <code>NullPointerException</code>, + <code>ArrayIndexOutOfBoundsException</code>, or + <code>ClassCastException</code>, without any other useful purposes. By + default, ProGuard may just discard such seemingly useless instructions, + resulting in better optimization of most common code.</dd> +</dl> + +<hr /> +<address> +Copyright © 2002-2017 +<a target="other" href="http://www.lafortune.eu/">Eric Lafortune</a> @ <a target="top" href="http://www.guardsquare.com/">GuardSquare</a>. +</address> +</body> +</html> |