LLVM has great support for interprocedural analysis and optimization.  It 
provides standard classes like call graphs, and provides a mature 
<a href="docs/AliasAnalysis.html">Alias Analysis Infrastructure</a> as well.  
LLVM includes several interprocedural optimizations, including inlining, IP constant 
propagation, dead argument elimination, dead global elimination, global 
variable constantization, by-ref to by-value argument promotion, etc.