Fixed to actually work correctly and be the basis for other tools by allowing the set of directories searched to be specified either by the LLVMDO_DIRS env var or by the -dirs "dirs..." command line option.
Fixed to actually work correctly and be the basis for other tools by
allowing the set of directories searched to be specified either by the
LLVMDO_DIRS env var or by the -dirs "dirs..." command line option.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@16441 91177308-0d34-0410-b5e6-96231b3b80d8

chubbymaggie/asap,GPUOpen-Drivers/llvm,chubbymaggie/asap,apple/swift-llvm,apple/swift-llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,chubbymaggie/asap,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,dslab-epfl/asap,apple/swift-llvm,dslab-epfl/asap,llvm-mirror/llvm,chubbymaggie/asap,dslab-epfl/asap,chubbymaggie/asap,llvm-mirror/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,dslab-epfl/asap,GPUOpen-Drivers/llvm,chubbymaggie/asap,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,dslab-epfl/asap,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm