83 lines
2.3 KiB
HTML
83 lines
2.3 KiB
HTML
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<html>
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<head>
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<title>
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Demo page information
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</title>
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</head>
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<body>
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<h1>Demo page information</h1>
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<p>Press "back" or <a href=".">click here</a> to return to the demo
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page.</p>
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<h2><a name="hints">Hints and Advice</a></h2>
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<ul>
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<li>The generated LLVM code will be easier to read if
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you use stdio (e.g., printf) than iostreams (e.g., std::cout).</li>
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<li>Unused inline functions and methods are not generated. Instead
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of '<tt>class foo { void bar() {}};</tt>',
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try writing '<tt>class foo { void bar(); }; void foo::bar() {}</tt>'.</li>
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<li>If you want to try out a file that uses non-standard header files, you should
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preprocess it (e.g., with the <tt>-save-temps</tt> or <tt>-E</tt> options to
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<tt>gcc</tt>) then upload the result.</li>
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</ul>
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<h2><a name="demangle">Demangle C++ names with C++ filt</a></h2>
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<p>
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Select this option if you want to run the output LLVM IR through "c++filt",
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which converts 'mangled' C++ names to their unmangled version.
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Note that LLVM code produced will not be lexically valid, but it will
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be easier to understand.
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</p>
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<h2><a name="lto">Run link-time optimizer</a></h2>
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<p>
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Select this option to run the LLVM link-time optimizer, which is designed to
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optimize across files in your application. Since the demo page doesn't allow
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you to upload multiple files at once, and does not link in any libraries, we
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configured the demo page optimizer to assume there are no calls
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coming in from outside the source file, allowing it to optimize more
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aggressively.</p>
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<p>Note that you have to define 'main' in your program for this
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to make much of a difference.
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</p>
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<h2><a name="stats">Show detailed pass statistics</a></h2>
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<p>
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Select this option to enable compilation timings and statistics from various
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optimizers.</p>
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<h2><a name="bcanalyzer">Analyze generated bytecode</a></h2>
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<p>
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Select this option to run the <a
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href="https://llvm.org/docs/CommandGuide/llvm-bcanalyzer.html">llvm-bcanalyzer</a> tool
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on the generated bytecode, which introspects into the format of the .bc file
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itself. </p>
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<h2><a name="llvm2cpp">Show C++ API code</a></h2>
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<p>
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Select this option to run the <a
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href="https://llvm.org/cmds/llvm2cpp.html">llvm2cpp</a> tool
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on the generated bytecode, which auto generates the C++ API calls that could
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be used to create the .bc file.
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</p>
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</body>
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</html>
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