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<h1>Compiling a Stylesheet</h1>
<p>The facility to "compile" a stylesheet to a binary disk representation (the <code>CompileStylesheet</code> command
and the -c option of <code>net.sf.saxon.Transform</code>) has been dropped with effect from Saxon 9.4.</p>
<p>Saxon now generates Java bytecode automatically when stylesheets are processed, but the bytecode
cannot be saved to disk, because it is integrated with interpreted data structures representing the
executable stylesheet.</p>
<p>The performance boost achieved by bytecode generation is variable; 25% is typical. The constructs that benefit the
most are those where the expression tree contains many constructs that are relatively cheap in themselves, such as
type conversion, comparisons, and arithmetic. This is because the saving from bytecode generation is mainly not in the
cost of performing primitive operations, but in the cost of deciding which operations to perform: so the saving is greater
where the number of operations is high relative to their average cost.</p>
<p>There are configuration options to suppress bytecode generation (<code>FeatureKeys.GENERATE_BYTE_CODE</code>), to
insert debugging logic into the generated bytecode (<code>FeatureKeys.DEBUG_BYTE_CODE</code>), and to display the generated
bytecode (<code>FeatureKeys.DISPLAY_BYTE_CODE</code>)</p>
<p>A new facility for distributing an obfuscated stylesheet is available (this was the main use
case for compiled stylesheets, since there were negligible performance benefits).
This is described in the next section.</p>
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