llvm-6502/docs/CommandGuide/llc.html
John Criswell 511a4917c4 Added information on input and output filenames.
Added periods to the end of sentence fragments describing options.
Added information to llc about which target architecture is selected for
assembly language code generation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8741 91177308-0d34-0410-b5e6-96231b3b80d8
2003-09-29 20:10:08 +00:00

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<html>
<title>
LLVM: llc tool
</title>
<body>
<center>
<h1>LLVM: llc tool</h1>
</center>
<HR>
<h3>
NAME
</h3>
llc
<h3>
SYNOPSIS
</h3>
llc [options] [filename]
<h3>
DESCRIPTION
</h3>
The llc command compiles LLVM bytecode into assembly language for a specified
architecture. The assembly language output can then be passed through a native
assembler and linker to generate native code.
<p>
The choice of architecture for the output assembly code is determined as
follows:
<ul>
<li>
If the user has specified an architecture with the -m option, use that
architecture.
<p>
<li>
Examine the input LLVM bytecode file:
<ul>
<li>
If it specifies little endian and a pointer size of 32 bits, select the
x86 architecture.
<p>
<li>
If it specifies big endian and a pointer size of 64 bit pointers,
select the SparcV9 architecture.
</ul>
<p>
<li>
If llc was compiled on an architecture for which it can generate code,
select the architecture upon which llc was compiled.
<p>
<li>
Print a message to the user asking him or her to specify the output
architecture explicitly.
</ul>
<p>
If filename is not specified, or if filename is -, llc reads its input from
standard input. Otherwise, it will read its input from filename.
<p>
If the -o option is left unspecified, then llc will send its output to standard
output if the input is from standard input. If the -o option specifies -, then
the output will also be sent to standard output.
<p>
If no -o option is specified and an input file other than - is specified, then
llc creates the output filename as follows:
<ul>
<li>
If the file ends in .bc, then the .bc suffix is removed, and the .s suffix
is appended.
<p>
<li>
Otherwise, the .s suffix is appended to the input filename.
</ul>
<h3>
OPTIONS
</h3>
<ul>
<li>-disable-fp-elim
<br>
Disable frame pointer elimination optimization.
<p>
<li>-disable-local-ra
<br>
Use Simple RA instead of Local RegAlloc.
<p>
<li>-disable-pattern-isel
<br>
Use the 'simple' X86 instruction selector.
<p>
<li>-disable-peephole
<br>
Disable peephole optimization pass.
<p>
<li>-disable-preopt
<br>
Disable optimizations prior to instruction selection.
<p>
<li>-disable-sched
<br>
Disable local scheduling pass.
<p>
<li>-disable-strip
<br>
Do not strip the LLVM bytecode included in executable.
<p>
<li>-enable-maps
<br>
Emit LLVM-to-MachineCode mapping info to assembly.
<p>
<li>-f
<br>
Overwrite output files
<p>
<li>-load=&lt;plugin.so&gt;
<br>
Load the specified plugin.
<p>
<li>-m&lt;arch&gt;
<br>
Specify the architecture for which to generate assembly. Valid
architectures are:
<dl compact>
<di> x86
<dd>
IA-32 (Pentium and above)
<p>
<di> sparc
<dd>SPARC V9
</dl>
<p>
<li>-o &lt;filename&gt;
<br>
Specify the output filename.
<p>
<li>-print-machineinstrs
<br>
Print generated machine code.
<p>
<li> -help
<br>
Print a summary of command line options.
<p>
<li> -stats
<br>
Print statistics.
<p>
<li> -time-passes
<br>
Record the amount of time needed for each pass and print it to standard
error.
<p>
</ul>
<h3>
EXIT STATUS
</h3>
If llc succeeds, it will exit with 0. Otherwise, if an error occurs, it
will exit with a non-zero value.
<h3>
SEE ALSO
</h3>
llvm-dis, lli
<HR>
<a href="http://llvm.cs.uiuc.edu">LLVM Team</a>
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