mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-11-02 22:04:55 +00:00
0d887a0942
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158359 91177308-0d34-0410-b5e6-96231b3b80d8
184 lines
4.5 KiB
ReStructuredText
184 lines
4.5 KiB
ReStructuredText
opt - LLVM optimizer
|
|
====================
|
|
|
|
|
|
SYNOPSIS
|
|
--------
|
|
|
|
|
|
**opt** [*options*] [*filename*]
|
|
|
|
|
|
DESCRIPTION
|
|
-----------
|
|
|
|
|
|
The **opt** command is the modular LLVM optimizer and analyzer. It takes LLVM
|
|
source files as input, runs the specified optimizations or analyses on it, and then
|
|
outputs the optimized file or the analysis results. The function of
|
|
**opt** depends on whether the **-analyze** option is given.
|
|
|
|
When **-analyze** is specified, **opt** performs various analyses of the input
|
|
source. It will usually print the results on standard output, but in a few
|
|
cases, it will print output to standard error or generate a file with the
|
|
analysis output, which is usually done when the output is meant for another
|
|
program.
|
|
|
|
While **-analyze** is *not* given, **opt** attempts to produce an optimized
|
|
output file. The optimizations available via **opt** depend upon what
|
|
libraries were linked into it as well as any additional libraries that have
|
|
been loaded with the **-load** option. Use the **-help** option to determine
|
|
what optimizations you can use.
|
|
|
|
If *filename* is omitted from the command line or is *-*, **opt** reads its
|
|
input from standard input. Inputs can be in either the LLVM assembly language
|
|
format (.ll) or the LLVM bitcode format (.bc).
|
|
|
|
If an output filename is not specified with the **-o** option, **opt**
|
|
writes its output to the standard output.
|
|
|
|
|
|
OPTIONS
|
|
-------
|
|
|
|
|
|
|
|
**-f**
|
|
|
|
Enable binary output on terminals. Normally, **opt** will refuse to
|
|
write raw bitcode output if the output stream is a terminal. With this option,
|
|
**opt** will write raw bitcode regardless of the output device.
|
|
|
|
|
|
|
|
**-help**
|
|
|
|
Print a summary of command line options.
|
|
|
|
|
|
|
|
**-o** *filename*
|
|
|
|
Specify the output filename.
|
|
|
|
|
|
|
|
**-S**
|
|
|
|
Write output in LLVM intermediate language (instead of bitcode).
|
|
|
|
|
|
|
|
**-{passname}**
|
|
|
|
**opt** provides the ability to run any of LLVM's optimization or analysis passes
|
|
in any order. The **-help** option lists all the passes available. The order in
|
|
which the options occur on the command line are the order in which they are
|
|
executed (within pass constraints).
|
|
|
|
|
|
|
|
**-std-compile-opts**
|
|
|
|
This is short hand for a standard list of *compile time optimization* passes.
|
|
This is typically used to optimize the output from the llvm-gcc front end. It
|
|
might be useful for other front end compilers as well. To discover the full set
|
|
of options available, use the following command:
|
|
|
|
|
|
.. code-block:: sh
|
|
|
|
llvm-as < /dev/null | opt -std-compile-opts -disable-output -debug-pass=Arguments
|
|
|
|
|
|
|
|
|
|
**-disable-inlining**
|
|
|
|
This option is only meaningful when **-std-compile-opts** is given. It simply
|
|
removes the inlining pass from the standard list.
|
|
|
|
|
|
|
|
**-disable-opt**
|
|
|
|
This option is only meaningful when **-std-compile-opts** is given. It disables
|
|
most, but not all, of the **-std-compile-opts**. The ones that remain are
|
|
**-verify**, **-lower-setjmp**, and **-funcresolve**.
|
|
|
|
|
|
|
|
**-strip-debug**
|
|
|
|
This option causes opt to strip debug information from the module before
|
|
applying other optimizations. It is essentially the same as **-strip** but it
|
|
ensures that stripping of debug information is done first.
|
|
|
|
|
|
|
|
**-verify-each**
|
|
|
|
This option causes opt to add a verify pass after every pass otherwise specified
|
|
on the command line (including **-verify**). This is useful for cases where it
|
|
is suspected that a pass is creating an invalid module but it is not clear which
|
|
pass is doing it. The combination of **-std-compile-opts** and **-verify-each**
|
|
can quickly track down this kind of problem.
|
|
|
|
|
|
|
|
**-profile-info-file** *filename*
|
|
|
|
Specify the name of the file loaded by the -profile-loader option.
|
|
|
|
|
|
|
|
**-stats**
|
|
|
|
Print statistics.
|
|
|
|
|
|
|
|
**-time-passes**
|
|
|
|
Record the amount of time needed for each pass and print it to standard
|
|
error.
|
|
|
|
|
|
|
|
**-debug**
|
|
|
|
If this is a debug build, this option will enable debug printouts
|
|
from passes which use the *DEBUG()* macro. See the **LLVM Programmer's
|
|
Manual**, section *#DEBUG* for more information.
|
|
|
|
|
|
|
|
**-load**\ =\ *plugin*
|
|
|
|
Load the dynamic object *plugin*. This object should register new optimization
|
|
or analysis passes. Once loaded, the object will add new command line options to
|
|
enable various optimizations or analyses. To see the new complete list of
|
|
optimizations, use the **-help** and **-load** options together. For example:
|
|
|
|
|
|
.. code-block:: sh
|
|
|
|
opt -load=plugin.so -help
|
|
|
|
|
|
|
|
|
|
**-p**
|
|
|
|
Print module after each transformation.
|
|
|
|
|
|
|
|
|
|
EXIT STATUS
|
|
-----------
|
|
|
|
|
|
If **opt** succeeds, it will exit with 0. Otherwise, if an error
|
|
occurs, it will exit with a non-zero value.
|