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$ svn merge -c 113303 https://llvm.org/svn/llvm-project/llvm/trunk --- Merging r113303 into '.': A docs/CommandGuide/llvm-diff.pod U docs/CommandGuide/index.html Log: Add documentation for llvm-diff. git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_28@113310 91177308-0d34-0410-b5e6-96231b3b80d8 Bill Wendling 8 years ago
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  • llvmc -
  • 7272 a generic customizable compiler driver
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  • llvm-diff -
  • 75 structurally compare two modules
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    0 =pod
    1
    2 =head1 NAME
    3
    4 llvm-diff - LLVM structural 'diff'
    5
    6 =head1 SYNOPSIS
    7
    8 B [I] I I [I]
    9
    10 =head1 DESCRIPTION
    11
    12 B compares the structure of two LLVM modules, primarily
    13 focusing on differences in function definitions. Insignificant
    14 differences, such as changes in the ordering of globals or in the
    15 names of local values, are ignored.
    16
    17 An input module will be interpreted as an assembly file if its name
    18 ends in '.ll'; otherwise it will be read in as a bitcode file.
    19
    20 If a list of global names is given, just the values with those names
    21 are compared; otherwise, all global values are compared, and
    22 diagnostics are produced for globals which only appear in one module
    23 or the other.
    24
    25 B compares two functions by comparing their basic blocks,
    26 beginning with the entry blocks. If the terminators seem to match,
    27 then the corresponding successors are compared; otherwise they are
    28 ignored. This algorithm is very sensitive to changes in control flow,
    29 which tend to stop any downstream changes from being detected.
    30
    31 B is intended as a debugging tool for writers of LLVM
    32 passes and frontends. It does not have a stable output format.
    33
    34 =head1 EXIT STATUS
    35
    36 If B finds no differences between the modules, it will exit
    37 with 0 and produce no output. Otherwise it will exit with a non-zero
    38 value.
    39
    40 =head1 BUGS
    41
    42 Many important differences, like changes in linkage or function
    43 attributes, are not diagnosed.
    44
    45 Changes in memory behavior (for example, coalescing loads) can cause
    46 massive detected differences in blocks.
    47
    48 =head1 AUTHORS
    49
    50 Maintained by the LLVM Team (L).
    51
    52 =cut