From 5d5cc59cc77afe655b3707cb0e69e0827b444cad Mon Sep 17 00:00:00 2001 From: dim Date: Fri, 17 Sep 2010 15:48:55 +0000 Subject: Vendor import of llvm r114020 (from the release_28 branch): http://llvm.org/svn/llvm-project/llvm/branches/release_28@114020 Approved by: rpaulo (mentor) --- docs/CommandGuide/llvm-diff.pod | 53 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 docs/CommandGuide/llvm-diff.pod (limited to 'docs/CommandGuide/llvm-diff.pod') diff --git a/docs/CommandGuide/llvm-diff.pod b/docs/CommandGuide/llvm-diff.pod new file mode 100644 index 0000000..c8cfdb3 --- /dev/null +++ b/docs/CommandGuide/llvm-diff.pod @@ -0,0 +1,53 @@ +=pod + +=head1 NAME + +llvm-diff - LLVM structural 'diff' + +=head1 SYNOPSIS + +B [I] I I [I] + +=head1 DESCRIPTION + +B 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 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 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 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). + +=cut -- cgit v1.1