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=pod

=head1 NAME

llc - LLVM static compiler

=head1 SYNOPSIS

B<llc> [I<options>] [I<filename>]

=head1 DESCRIPTION

The B<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.

The choice of architecture for the output assembly code is automatically 
determined from the input bytecode file, unless a B<-m> option is used to override
the default.

=head1 OPTIONS

If I<filename> is - or omitted, B<llc> reads LLVM bytecode from standard input.
Otherwise, it will read LLVM bytecode from I<filename>.

If the B<-o> option is omitted, then B<llc> will send its output to standard
output if the input is from standard input.  If the B<-o> option specifies -,
then the output will also be sent to standard output.

If no B<-o> option is specified and an input file other than - is specified,
then B<llc> creates the output filename by taking the input filename,
removing any existing F<.bc> extension, and adding a F<.s> suffix.

Other B<llc> options are as follows:

=over

=item B<-f>

Overwrite output files. By default, B<llc> will refuse to overwrite
an output file which already exists.

=item B<-march>=I<arch>

Specify the architecture for which to generate assembly.  Valid
architectures are:

=over

=item I<x86>

Intel IA-32 (Pentium and above)

=item I<ppc32>

32-bit PowerPC (MacOS X, 32-bit ABI)

=item I<sparcv9>

64-bit SPARC V9

=item I<c>

Emit C code, not assembly

=back

=item B<--disable-fp-elim>

Disable frame pointer elimination optimization.

=item B<--enable-correct-eh-support>

Instruct the B<lowerinvoke> pass to insert code for correct exception handling
support.  This is expensive and is by default omitted for efficiency.

=item B<--help>

Print a summary of command line options.

=item B<--stats>

Print statistics recorded by code-generation passes.

=item B<--time-passes>

Record the amount of time needed for each pass and print a report to standard
error.

=item B<--print-machineinstrs>

Print generated machine code between compilation phases (useful for debugging).

=item B<--regalloc>=I<allocator>

Specify the register allocator to use. The default I<allocator> is I<local>.
Valid register allocators are:

=over

=item I<simple>

Very simple "always spill" register allocator

=item I<local>

Local register allocator

=item I<linearscan>

Linear scan global register allocator

=item I<iterativescan>

Iterative scan global register allocator

=back

=item B<--spiller>=I<spiller>

Specify the spiller to use for register allocators that support it.  Currently
this option is used only by the linear scan register allocator. The default
I<spiller> is I<local>.  Valid spillers are:

=over

=item I<simple>

Simple spiller

=item I<local>

Local spiller

=back

=back

=head2 Intel IA-32-specific Options

=over

=item B<--x86-asm-syntax=att|intel>

Specify whether to emit assembly code in AT&T syntax (the default) or intel
syntax.

=back

=head2 SPARCV9-specific Options

=over

=item B<--disable-peephole>

Disable peephole optimization pass.

=item B<--disable-sched>

Disable local scheduling pass.

=back

=head1 EXIT STATUS

If B<llc> succeeds, it will exit with 0.  Otherwise, if an error occurs,
it will exit with a non-zero value.

=head1 SEE ALSO

L<lli|lli>

=head1 AUTHORS

Maintained by the LLVM Team (L<http://llvm.cs.uiuc.edu>).

=cut