From 3b709d5f5532bacb6c351def8c9bc7efef36fa33 Mon Sep 17 00:00:00 2001 From: Daniel Dunbar Date: Tue, 8 May 2012 16:50:35 +0000 Subject: [docs] Add ReST version of all the man pages. - The POD versions are slated for execution, but are still around until llvm.org machinery is in place. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156384 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/CommandGuide/llvm-diff.rst | 56 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 docs/CommandGuide/llvm-diff.rst (limited to 'docs/CommandGuide/llvm-diff.rst') diff --git a/docs/CommandGuide/llvm-diff.rst b/docs/CommandGuide/llvm-diff.rst new file mode 100644 index 0000000000..991d4fece0 --- /dev/null +++ b/docs/CommandGuide/llvm-diff.rst @@ -0,0 +1,56 @@ +llvm-diff - LLVM structural 'diff' +================================== + + +SYNOPSIS +-------- + + +**llvm-diff** [*options*] *module 1* *module 2* [*global name ...*] + + +DESCRIPTION +----------- + + +**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. + +**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. + +**llvm-diff** is intended as a debugging tool for writers of LLVM +passes and frontends. It does not have a stable output format. + + +EXIT STATUS +----------- + + +If **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. + + +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. -- cgit v1.2.3-70-g09d2