src/llvm/docs/CommandGuide/bugpoint.rst

   1 bugpoint - automatic test case reduction tool
   2 =============================================
   3
   4 SYNOPSIS
   5 --------
   6
   7 **bugpoint** [*options*] [*input LLVM ll/bc files*] [*LLVM passes*] **--args**
   8 *program arguments*
   9
  10 DESCRIPTION
  11 -----------
  12
  13 **bugpoint** narrows down the source of problems in LLVM tools and passes.  It
  14 can be used to debug three types of failures: optimizer crashes, miscompilations
  15 by optimizers, or bad native code generation (including problems in the static
  16 and JIT compilers).  It aims to reduce large test cases to small, useful ones.
  17 For more information on the design and inner workings of **bugpoint**, as well as
  18 advice for using bugpoint, see *llvm/docs/Bugpoint.html* in the LLVM
  19 distribution.
  20
  21 OPTIONS
  22 -------
  23
  24 **--additional-so** *library*
  25
  26  Load the dynamic shared object *library* into the test program whenever it is
  27  run.  This is useful if you are debugging programs which depend on non-LLVM
  28  libraries (such as the X or curses libraries) to run.
  29
  30 **--append-exit-code**\ =\ *{true,false}*
  31
  32  Append the test programs exit code to the output file so that a change in exit
  33  code is considered a test failure. Defaults to false.
  34
  35 **--args** *program args*
  36
  37  Pass all arguments specified after **--args** to the test program whenever it runs.
  38  Note that if any of the *program args* start with a "``-``", you should use:
  39
  40  .. code-block:: bash
  41
  42       bugpoint [bugpoint args] --args -- [program args]
  43
  44  The "``--``" right after the **--args** option tells **bugpoint** to consider
  45  any options starting with "``-``" to be part of the **--args** option, not as
  46  options to **bugpoint** itself.
  47
  48 **--tool-args** *tool args*
  49
  50  Pass all arguments specified after **--tool-args** to the LLVM tool under test
  51  (**llc**, **lli**, etc.) whenever it runs.  You should use this option in the
  52  following way:
  53
  54  .. code-block:: bash
  55
  56       bugpoint [bugpoint args] --tool-args -- [tool args]
  57
  58  The "``--``" right after the **--tool-args** option tells **bugpoint** to
  59  consider any options starting with "``-``" to be part of the **--tool-args**
  60  option, not as options to **bugpoint** itself. (See **--args**, above.)
  61
  62 **--safe-tool-args** *tool args*
  63
  64  Pass all arguments specified after **--safe-tool-args** to the "safe" execution
  65  tool.
  66
  67 **--gcc-tool-args** *gcc tool args*
  68
  69  Pass all arguments specified after **--gcc-tool-args** to the invocation of
  70  **gcc**.
  71
  72 **--opt-args** *opt args*
  73
  74  Pass all arguments specified after **--opt-args** to the invocation of **opt**.
  75
  76 **--disable-{dce,simplifycfg}**
  77
  78  Do not run the specified passes to clean up and reduce the size of the test
  79  program. By default, **bugpoint** uses these passes internally when attempting to
  80  reduce test programs.  If you're trying to find a bug in one of these passes,
  81  **bugpoint** may crash.
  82
  83 **--enable-valgrind**
  84
  85  Use valgrind to find faults in the optimization phase. This will allow
  86  bugpoint to find otherwise asymptomatic problems caused by memory
  87  mis-management.
  88
  89 **-find-bugs**
  90
  91  Continually randomize the specified passes and run them on the test program
  92  until a bug is found or the user kills **bugpoint**.
  93
  94 **-help**
  95
  96  Print a summary of command line options.
  97
  98 **--input** *filename*
  99
 100  Open *filename* and redirect the standard input of the test program, whenever
 101  it runs, to come from that file.
 102
 103 **--load** *plugin*
 104
 105  Load the dynamic object *plugin* into **bugpoint** itself.  This object should
 106  register new optimization passes.  Once loaded, the object will add new command
 107  line options to enable various optimizations.  To see the new complete list of
 108  optimizations, use the **-help** and **--load** options together; for example:
 109
 110
 111  .. code-block:: bash
 112
 113       bugpoint --load myNewPass.so -help
 114
 115 **--mlimit** *megabytes*
 116
 117  Specifies an upper limit on memory usage of the optimization and codegen. Set
 118  to zero to disable the limit.
 119
 120 **--output** *filename*
 121
 122  Whenever the test program produces output on its standard output stream, it
 123  should match the contents of *filename* (the "reference output"). If you
 124  do not use this option, **bugpoint** will attempt to generate a reference output
 125  by compiling the program with the "safe" backend and running it.
 126
 127 **--run-{int,jit,llc,custom}**
 128
 129  Whenever the test program is compiled, **bugpoint** should generate code for it
 130  using the specified code generator.  These options allow you to choose the
 131  interpreter, the JIT compiler, the static native code compiler, or a
 132  custom command (see **--exec-command**) respectively.
 133
 134 **--safe-{llc,custom}**
 135
 136  When debugging a code generator, **bugpoint** should use the specified code
 137  generator as the "safe" code generator. This is a known-good code generator
 138  used to generate the "reference output" if it has not been provided, and to
 139  compile portions of the program that as they are excluded from the testcase.
 140  These options allow you to choose the
 141  static native code compiler, or a custom command, (see **--exec-command**)
 142  respectively. The interpreter and the JIT backends cannot currently
 143  be used as the "safe" backends.
 144
 145 **--exec-command** *command*
 146
 147  This option defines the command to use with the **--run-custom** and
 148  **--safe-custom** options to execute the bitcode testcase. This can
 149  be useful for cross-compilation.
 150
 151 **--compile-command** *command*
 152
 153  This option defines the command to use with the **--compile-custom**
 154  option to compile the bitcode testcase. This can be useful for
 155  testing compiler output without running any link or execute stages. To
 156  generate a reduced unit test, you may add CHECK directives to the
 157  testcase and pass the name of an executable compile-command script in this form:
 158
 159  .. code-block:: sh
 160
 161       #!/bin/sh
 162       llc "$@"
 163       not FileCheck [bugpoint input file].ll < bugpoint-test-program.s
 164
 165  This script will "fail" as long as FileCheck passes. So the result
 166  will be the minimum bitcode that passes FileCheck.
 167
 168 **--safe-path** *path*
 169
 170  This option defines the path to the command to execute with the
 171  **--safe-{int,jit,llc,custom}**
 172  option.
 173
 174 EXIT STATUS
 175 -----------
 176
 177 If **bugpoint** succeeds in finding a problem, it will exit with 0.  Otherwise,
 178 if an error occurs, it will exit with a non-zero value.
 179
 180 SEE ALSO
 181 --------
 182
 183 opt|opt