Migrate away from using a Subtarget except for the one place we want to use it. Use the triple to determine OS format bits at the module level.
Migrate away from using a Subtarget except for the one place we want
to use it. Use the triple to determine OS format bits at the module
level.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@227947 91177308-0d34-0410-b5e6-96231b3b80d8

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