NAME

llc - LLVM static compiler

SYNOPSIS

llc [options] [filename]

DESCRIPTION

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.

The choice of architecture for the output assembly code is determined as follows, by attempting to satisfy each of the following rules in turn (first one wins):

If the user has specified an architecture with the -m option, use that architecture.
Examine the input LLVM bytecode file: if it is little endian and has a pointer size of 32 bits, select the Intel IA-32 architecture. If it is big endian and has a pointer size of 64 bits, select the SparcV9 architecture.
If llc was compiled on an architecture for which it can generate code, select the architecture upon which llc was compiled.
Exit with an error message telling the user to specify the output architecture explicitly.

OPTIONS

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

If the -o option is omitted, 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.

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

Other llc options are as follows:

-f

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

-march=arch

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

x86

Intel IA-32 (Pentium and above)

sparcv9

64-bit SPARC V9

c

Emit C code, not assembly

-enable-correct-eh-support

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

-help

Print a summary of command line options.

-stats

Print statistics recorded by code-generation passes.

-time-passes

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

Intel IA-32-specific Options

--disable-fp-elim

Disable frame pointer elimination optimization.

--disable-pattern-isel

Use the 'simple' X86 instruction selector (the default).

--print-machineinstrs

Print generated machine code.

--regalloc=allocator

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

simple

Very simple ``always spill'' register allocator

local

Local register allocator

linearscan

Linear scan global register allocator

iterativescan

Iterative scan global register allocator

--spiller=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 spiller is local. Valid spillers are:

simple

Simple spiller

local

Local spiller

SPARCV9-specific Options

--disable-peephole

Disable peephole optimization pass.

--disable-sched

Disable local scheduling pass.

--disable-strip

The Sparc backend embeds the LLVM bytecode into the assembly output. This option requests that symbol names be retained; by default, they are stripped out.

--enable-maps

Emit LLVM-to-machine code mapping information into the assembly output.

EXIT STATUS

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

SEE ALSO

lli

AUTHORS

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