2 <title>LLVM: opt tool</title>
6 <center><h1>LLVM: <tt>opt</tt> tool</h1></center>
13 <tt>opt [options] [filename]</tt>
17 The <tt>opt</tt> command is the modular LLVM optimizer. It takes LLVM bytecode
18 as input, runs the specified optimizations on it, and then outputs the optimized
22 The optimizations available via <tt>opt</tt> depend upon what libraries were
23 linked into it as well as any additional libraries that have been loaded with
24 the <tt>-load</tt> option. Use the <tt>-help</tt> option to determine what
25 optimizations you can use.
28 If no filename is specified on the command line, <tt>opt</tt> reads its input
32 If an output filename is not specified with the <tt>-o</tt> option, <tt>opt</tt>
33 writes its output to the standard output.
41 Force overwrite. Normally, <tt>opt</tt> will refuse to overwrite an
42 output file that already exists. With this option, <tt>opt</tt> will
43 overwrite the output file and replace it with new bytecode.
48 Print a summary of command line options.
51 <li> -o <filename>
53 Specify the output filename.
56 <li> -profile-info-file <filename>
58 Specify the name of the file loaded by the -profile-loader option.
68 Record the amount of time needed for each pass and print it to standard
74 If this is a debug build, this option will enable debug printouts from
75 passes which use the <tt>DEBUG</tt> macro. See the <a
76 href="../ProgrammersManual.html#DEBUG">Programmer's Manual</a> for more
80 <li> -load <plugin>
82 Load the dynamic object <plugin>. This object should register new
83 optimization passes. Once loaded, the object will add new command line
84 options to enable various optimizations. To see the new complete list
85 of optimizations, use the -help and -load options together:
87 <tt>opt -load <plugin> -help</tt>
92 Print module after each transformation.
98 If <tt>opt</tt> succeeds, it will exit with 0. Otherwise, if an error occurs,
99 it will exit with a non-zero value.
103 <a href="analyze.html"><tt>analyze</tt></a>
106 Maintained by the <a href="http://llvm.cs.uiuc.edu">LLVM Team</a>.