This page describes how to build mesa with llvm support.
First build llvm from svn with clang support:
svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm
cd llvm
./configure --enable-pic
make
make install
cd tools
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang
cd clang
make
make install
Next build mesa with llvm support:
git clone git+ssh://marcheu@git.freedesktop.org/git/mesa/mesa
cd mesa
git checkout --track -b gallium-0.2 origin/gallium-0.2
make linux-llvm
Mesa-7.9 [still unreleased as of 17-09-2010, but already branched from master] has configure switch for autoconf-based build system:
--enable-gallium-llvm