Log Message:
LLVM 3.0 includes several major changes and big features:
* llvm-gcc is no longer supported, and not included in the release. We recommend
  switching to Clang or DragonEgg.
* The linear scan register allocator has been replaced with a new "greedy"
  register allocator, enabling live range splitting and many other optimizations \ 
 that lead to better code quality. Please see its blog post or its talk at the
  Developer Meeting for more information.
* LLVM IR now includes full support for atomics memory operations intended to
  support the C++'11 and C'1x memory models. This includes atomic load and
  store, compare and exchange, and read/modify/write instructions as well as
  a full set of memory ordering constraints. Please see the Atomics Guide for
  more information.
* The LLVM IR exception handling representation has been redesigned and
  reimplemented, making it more elegant, fixing a huge number of bugs, and
  enabling inlining and other optimizations. Please see its blog post and the
  Exception Handling documentation for more information.
* The LLVM IR Type system has been redesigned and reimplemented, making it
  faster and solving some long-standing problems. Please see its blog post for
  more information.
* The MIPS backend has made major leaps in this release, going from an
  experimental target to being virtually production quality and supporting
  a wide variety of MIPS subtargets. See the MIPS section below for more
  information.
* The optimizer and code generator now supports gprof and gcov-style coverage
  and profiling information, and includes a new llvm-cov tool (but also works
  with gcov). Clang exposes coverage and profiling through GCC-compatible
  command line options.