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lli - directly execute programs from LLVM bitcode


**lli** [*options*] [*filename*] [*program args*]


**lli** directly executes programs in LLVM bitcode format.  It takes a program
in LLVM bitcode format and executes it using a just-in-time compiler, if one is
available for the current architecture, or an interpreter.  **lli** takes all of
the same code generator options as llc|llc, but they are only effective when
**lli** is using the just-in-time compiler.

If *filename* is not specified, then **lli** reads the LLVM bitcode for the
program from standard input.

The optional *args* specified on the command line are passed to the program as


**-fake-argv0**\ =\ *executable*

 Override the ``argv[0]`` value passed into the executing program.

**-force-interpreter**\ =\ *{false,true}*

 If set to true, use the interpreter even if a just-in-time compiler is available
 for this architecture. Defaults to false.


 Print a summary of command line options.

**-load**\ =\ *pluginfilename*

 Causes **lli** to load the plugin (shared object) named *pluginfilename* and use
 it for optimization.


 Print statistics from the code-generation passes. This is only meaningful for
 the just-in-time compiler, at present.


 Record the amount of time needed for each code-generation pass and print it to
 standard error.


 Print out the version of **lli** and exit without doing anything else.


**-mtriple**\ =\ *target triple*

 Override the target triple specified in the input bitcode file with the
 specified string.  This may result in a crash if you pick an
 architecture which is not compatible with the current system.

**-march**\ =\ *arch*

 Specify the architecture for which to generate assembly, overriding the target
 encoded in the bitcode 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 architecture.

**-mcpu**\ =\ *cpuname*

 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**

**-mattr**\ =\ *a1,+a2,-a3,...*

 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 optimizations that may increase floating point precision.


 Enable optimizations that assume no Inf values.


 Enable optimizations that assume no NAN values.


 Causes **lli** to enable optimizations that may decrease floating point


 Causes **lli** to generate software floating point library calls instead of
 equivalent hardware instructions.


**-code-model**\ =\ *model*

 Choose the code model from:

 .. code-block:: perl

      default: Target default code model
      small: Small code model
      kernel: Kernel code model
      medium: Medium code model
      large: Large code model


 Disable scheduling after register allocation.


 Disable fusing of spill code into instructions.


 Make the -lowerinvoke pass insert expensive, but correct, EH code.


 Exception handling should be enabled in the just-in-time compiler.


 Coalesce copies (default=true).

**-nozero-initialized-in-bss** Don't place zero-initialized symbols into the BSS section.

**-pre-RA-sched**\ =\ *scheduler*

 Instruction schedulers available (before register allocation):

 .. code-block:: perl

      =default: Best scheduler for the target
      =none: No scheduling: breadth first sequencing
      =simple: Simple two pass scheduling: minimize critical path and maximize processor utilization
      =simple-noitin: Simple two pass scheduling: Same as simple except using generic latency
      =list-burr: Bottom-up register reduction list scheduling
      =list-tdrr: Top-down register reduction list scheduling
      =list-td: Top-down list scheduler -print-machineinstrs - Print generated machine code

**-regalloc**\ =\ *allocator*

 Register allocator to use (default=linearscan)

 .. code-block:: perl

      =bigblock: Big-block register allocator
      =linearscan: linear scan register allocator =local -   local register allocator
      =simple: simple register allocator

**-relocation-model**\ =\ *model*

 Choose relocation model from:

 .. code-block:: perl

      =default: Target default relocation model
      =static: Non-relocatable code =pic -   Fully relocatable, position independent code
      =dynamic-no-pic: Relocatable external references, non-relocatable code


 Spiller to use (default=local)

 .. code-block:: perl

      =simple: simple spiller
      =local: local spiller

**-x86-asm-syntax**\ =\ *syntax*

 Choose style of code to emit from X86 backend:

 .. code-block:: perl

      =att: Emit AT&T-style assembly
      =intel: Emit Intel-style assembly


If **lli** fails to load the program, it will exit with an exit code of 1.
Otherwise, it will return the exit code of the program it executes.