203 lines
8.3 KiB
HTML
203 lines
8.3 KiB
HTML
<!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.saikoa.com/dexguard">DexGuard</a> <a class="largebutton" target="_top" href="http://www.saikoa.com/">Saikoa</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.saikoa.com/dexguard">DexGuard</a>
|
|
<a class="largebutton" target="_top" href="http://www.saikoa.com/">Saikoa</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 © 2002-2014
|
|
<a target="other" href="http://www.lafortune.eu/">Eric Lafortune</a> @ <a target="top" href="http://www.saikoa.com/">Saikoa</a>.
|
|
</address>
|
|
</body>
|
|
</html>
|