mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-29 10:32:47 +00:00
54 lines
1.6 KiB
Plaintext
54 lines
1.6 KiB
Plaintext
|
=pod
|
||
|
|
|
||
|
|
=head1 NAME
|
||
|
|
|
||
|
|
llvm-diff - LLVM structural 'diff'
|
||
|
|
|
||
|
|
=head1 SYNOPSIS
|
||
|
|
|
||
|
|
B<llvm-diff> [I<options>] I<module 1> I<module 2> [I<global name ...>]
|
||
|
|
|
||
|
|
=head1 DESCRIPTION
|
||
|
|
|
||
|
|
B<llvm-diff> compares the structure of two LLVM modules, primarily
|
||
|
|
focusing on differences in function definitions. Insignificant
|
||
|
|
differences, such as changes in the ordering of globals or in the
|
||
|
|
names of local values, are ignored.
|
||
|
|
|
||
|
|
An input module will be interpreted as an assembly file if its name
|
||
|
|
ends in '.ll'; otherwise it will be read in as a bitcode file.
|
||
|
|
|
||
|
|
If a list of global names is given, just the values with those names
|
||
|
|
are compared; otherwise, all global values are compared, and
|
||
|
|
diagnostics are produced for globals which only appear in one module
|
||
|
|
or the other.
|
||
|
|
|
||
|
|
B<llvm-diff> compares two functions by comparing their basic blocks,
|
||
|
|
beginning with the entry blocks. If the terminators seem to match,
|
||
|
|
then the corresponding successors are compared; otherwise they are
|
||
|
|
ignored. This algorithm is very sensitive to changes in control flow,
|
||
|
|
which tend to stop any downstream changes from being detected.
|
||
|
|
|
||
|
|
B<llvm-diff> is intended as a debugging tool for writers of LLVM
|
||
|
|
passes and frontends. It does not have a stable output format.
|
||
|
|
|
||
|
|
=head1 EXIT STATUS
|
||
|
|
|
||
|
|
If B<llvm-diff> finds no differences between the modules, it will exit
|
||
|
|
with 0 and produce no output. Otherwise it will exit with a non-zero
|
||
|
|
value.
|
||
|
|
|
||
|
|
=head1 BUGS
|
||
|
|
|
||
|
|
Many important differences, like changes in linkage or function
|
||
|
|
attributes, are not diagnosed.
|
||
|
|
|
||
|
|
Changes in memory behavior (for example, coalescing loads) can cause
|
||
|
|
massive detected differences in blocks.
|
||
|
|
|
||
|
|
=head1 AUTHORS
|
||
|
|
|
||
|
|
Maintained by the LLVM Team (L<http://llvm.org>).
|
||
|
|
|
||
|
|
=cut
|