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Updated: Wednesday, February 9, 2022

llc (1)


llc - LLVM static compiler


llc [options] [filename]


LLC(1)                               LLVM                               LLC(1)

       llc - LLVM static compiler

       llc [options] [filename]

       The  llc command compiles LLVM source inputs into assembly language for
       a specified architecture.  The assembly language  output  can  then  be
       passed  through a native assembler and linker to generate a native exe-

       The choice of architecture for the output assembly  code  is  automati-
       cally  determined from the input file, unless the -march option is used
       to override the default.

       If filename is "-" or omitted, llc reads from standard  input.   Other-
       wise, it will from filename.  Inputs can be in either the LLVM assembly
       language format (.ll) or the LLVM bitcode format (.bc).

       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 speci-
       fied,  then  llc  creates the output filename by taking the input file-
       name, removing any existing .bc extension, and adding a .s suffix.

       Other llc options are described below.

   End-user Options
       -help  Print a summary of command line options.

              Generate code at different optimization  levels.   These  corre-
              spond  to the -O0, -O1, -O2, and -O3 optimization levels used by

       -mtriple=<target triple>
              Override the target triple specified in the input file with  the
              specified string.

              Specify  the  architecture for which to generate assembly, over-
              riding the target encoded in the input file.  See the output  of
              llc -help for a list of valid architectures.  By default this is
              inferred from the target triple or autodetected to  the  current

              Specify  a specific chip in the current architecture to generate
              code for.  By default this is inferred from  the  target  triple
              and  autodetected  to  the  current architecture.  For a list of
              available CPUs, use:

                 llvm-as < /dev/null | llc -march=xyz -mcpu=help

       -filetype=<output file type>
              Specify what kind of output llc should generated.  Options  are:
              asm  for  textual  assembly ( '.s'), obj for native object files
              ('.o') and null for not emitting anything (for performance test-

              Note that not all targets support all options.

              Override  or  control specific attributes of the target, such as
              whether SIMD operations are enabled or not.  The default set  of
              attributes  is  set by the current CPU.  For a list of available
              attributes, use:

                 llvm-as < /dev/null | llc -march=xyz -mattr=help

              Disable frame pointer elimination optimization.

              Disable optimizations that  may  produce  excess  precision  for
              floating  point.   Note  that  this option can dramatically slow
              down code on some systems (e.g. X86).

              Enable optimizations that assume no Inf values.

              Enable optimizations that assume no NAN values.

              Enable optimizations that make  unsafe  assumptions  about  IEEE
              math (e.g. that addition is associative) or may not work for all
              input ranges.  These optimizations allow the code  generator  to
              make  use  of  some  instructions  which  would otherwise not be
              usable (such as fsin on X86).

              Print statistics recorded by code-generation passes.

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

              Dynamically  load  dso_path  (a  path  to  a  dynamically shared
              object) that implements an LLVM target.  This  will  permit  the
              target  name  to be used with the -march option so that code can
              be generated for that target.

              Specify which EABI version should conform to.  Valid  EABI  ver-
              sions  are gnu, 4 and 5.  Default value (default) depends on the

   Tuning/Configuration Options
              Print generated machine code between compilation phases  (useful
              for debugging).

              Specify  the  register allocator to use.  Valid register alloca-
              tors are:

                 Basic register allocator.

                 Fast register allocator. It is the  default  for  unoptimized

                 Greedy  register  allocator.  It is the default for optimized

                 Register allocator based on  'Partitioned  Boolean  Quadratic

              Specify  the spiller to use for register allocators that support
              it.  Currently this option is used only by the linear scan  reg-
              ister  allocator.  The default spiller is local.  Valid spillers

                 Simple spiller

                 Local spiller

   Intel IA-32-specific Options
              Specify whether to  emit  assembly  code  in  AT&T  syntax  (the
              default) or Intel syntax.

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

       See attributes(7) for descriptions of the following attributes:

       |Availability   | developer/llvm/llvm |
       |Stability      | Uncommitted         |


       Maintained by The LLVM Team (http://llvm.org/).

       2003-2016, LLVM Project

       Source code for open source software components in Oracle  Solaris  can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source    was    downloaded     from      https://github.com/llvm/llvm-

       Further information about this software can be found on the open source
       community website at https://llvm.org/.

3.8                               2016-07-10                            LLC(1)