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1lli - directly execute programs from LLVM bitcode
2=================================================
3
4SYNOPSIS
5--------
6
7:program:`lli` [*options*] [*filename*] [*program args*]
8
9DESCRIPTION
10-----------
11
12:program:`lli` directly executes programs in LLVM bitcode format.  It takes a program
13in LLVM bitcode format and executes it using a just-in-time compiler or an
14interpreter.
15
16:program:`lli` is *not* an emulator. It will not execute IR of different architectures
17and it can only interpret (or JIT-compile) for the host architecture.
18
19The JIT compiler takes the same arguments as other tools, like :program:`llc`,
20but they don't necessarily work for the interpreter.
21
22If `filename` is not specified, then :program:`lli` reads the LLVM bitcode for the
23program from standard input.
24
25The optional *args* specified on the command line are passed to the program as
26arguments.
27
28GENERAL OPTIONS
29---------------
30
31.. option:: -fake-argv0=executable
32
33 Override the ``argv[0]`` value passed into the executing program.
34
35.. option:: -force-interpreter={false,true}
36
37 If set to true, use the interpreter even if a just-in-time compiler is available
38 for this architecture. Defaults to false.
39
40.. option:: -help
41
42 Print a summary of command line options.
43
44.. option:: -load=pluginfilename
45
46 Causes :program:`lli` to load the plugin (shared object) named *pluginfilename* and use
47 it for optimization.
48
49.. option:: -stats
50
51 Print statistics from the code-generation passes. This is only meaningful for
52 the just-in-time compiler, at present.
53
54.. option:: -time-passes
55
56 Record the amount of time needed for each code-generation pass and print it to
57 standard error.
58
59.. option:: -version
60
61 Print out the version of :program:`lli` and exit without doing anything else.
62
63TARGET OPTIONS
64--------------
65
66.. option:: -mtriple=target triple
67
68 Override the target triple specified in the input bitcode file with the
69 specified string.  This may result in a crash if you pick an
70 architecture which is not compatible with the current system.
71
72.. option:: -march=arch
73
74 Specify the architecture for which to generate assembly, overriding the target
75 encoded in the bitcode file.  See the output of **llc -help** for a list of
76 valid architectures.  By default this is inferred from the target triple or
77 autodetected to the current architecture.
78
79.. option:: -mcpu=cpuname
80
81 Specify a specific chip in the current architecture to generate code for.
82 By default this is inferred from the target triple and autodetected to
83 the current architecture.  For a list of available CPUs, use:
84 **llvm-as < /dev/null | llc -march=xyz -mcpu=help**
85
86.. option:: -mattr=a1,+a2,-a3,...
87
88 Override or control specific attributes of the target, such as whether SIMD
89 operations are enabled or not.  The default set of attributes is set by the
90 current CPU.  For a list of available attributes, use:
91 **llvm-as < /dev/null | llc -march=xyz -mattr=help**
92
93FLOATING POINT OPTIONS
94----------------------
95
96.. option:: -disable-excess-fp-precision
97
98 Disable optimizations that may increase floating point precision.
99
100.. option:: -enable-no-infs-fp-math
101
102 Enable optimizations that assume no Inf values.
103
104.. option:: -enable-no-nans-fp-math
105
106 Enable optimizations that assume no NAN values.
107
108.. option:: -enable-unsafe-fp-math
109
110 Causes :program:`lli` to enable optimizations that may decrease floating point
111 precision.
112
113.. option:: -soft-float
114
115 Causes :program:`lli` to generate software floating point library calls instead of
116 equivalent hardware instructions.
117
118CODE GENERATION OPTIONS
119-----------------------
120
121.. option:: -code-model=model
122
123 Choose the code model from:
124
125 .. code-block:: perl
126
127      default: Target default code model
128      small: Small code model
129      kernel: Kernel code model
130      medium: Medium code model
131      large: Large code model
132
133.. option:: -disable-post-RA-scheduler
134
135 Disable scheduling after register allocation.
136
137.. option:: -disable-spill-fusing
138
139 Disable fusing of spill code into instructions.
140
141.. option:: -jit-enable-eh
142
143 Exception handling should be enabled in the just-in-time compiler.
144
145.. option:: -join-liveintervals
146
147 Coalesce copies (default=true).
148
149.. option:: -nozero-initialized-in-bss
150
151  Don't place zero-initialized symbols into the BSS section.
152
153.. option:: -pre-RA-sched=scheduler
154
155 Instruction schedulers available (before register allocation):
156
157 .. code-block:: perl
158
159      =default: Best scheduler for the target
160      =none: No scheduling: breadth first sequencing
161      =simple: Simple two pass scheduling: minimize critical path and maximize processor utilization
162      =simple-noitin: Simple two pass scheduling: Same as simple except using generic latency
163      =list-burr: Bottom-up register reduction list scheduling
164      =list-tdrr: Top-down register reduction list scheduling
165      =list-td: Top-down list scheduler -print-machineinstrs - Print generated machine code
166
167.. option:: -regalloc=allocator
168
169 Register allocator to use (default=linearscan)
170
171 .. code-block:: perl
172
173      =bigblock: Big-block register allocator
174      =linearscan: linear scan register allocator =local -   local register allocator
175      =simple: simple register allocator
176
177.. option:: -relocation-model=model
178
179 Choose relocation model from:
180
181 .. code-block:: perl
182
183      =default: Target default relocation model
184      =static: Non-relocatable code =pic -   Fully relocatable, position independent code
185      =dynamic-no-pic: Relocatable external references, non-relocatable code
186
187.. option:: -spiller
188
189 Spiller to use (default=local)
190
191 .. code-block:: perl
192
193      =simple: simple spiller
194      =local: local spiller
195
196.. option:: -x86-asm-syntax=syntax
197
198 Choose style of code to emit from X86 backend:
199
200 .. code-block:: perl
201
202      =att: Emit AT&T-style assembly
203      =intel: Emit Intel-style assembly
204
205EXIT STATUS
206-----------
207
208If :program:`lli` fails to load the program, it will exit with an exit code of 1.
209Otherwise, it will return the exit code of the program it executes.
210
211SEE ALSO
212--------
213
214:program:`llc`
215