Analysis and optimizations that work on more than one procedure at a time. This is usually done by making walking the Strongly Connected Components of the call graph, and performing some analysis and optimization across some set of procedures (be it the whole program, or just a subset) at once.
GCC has had a callgraph for a few versions now (since GCC 3.4 in the FSF releases), but the procedures didn't have control flow graphs (CFGs) built. The tree-profiling-branch in GCC CVS now has a CFG for every procedure built and accessible from the callgraph, as well as a basic IPA pass manager. It also contains in-progress interprocedural optimizations and analyses: interprocedural constant propagation (with cloning for specialization) and interprocedural type escape analysis.