Add support for promoting stores from one legal type to another, allowing us to write one pattern for vector stores instead of 4.
Add support for promoting stores from one legal type to another, allowing us
to write one pattern for vector stores instead of 4.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@27730 91177308-0d34-0410-b5e6-96231b3b80d8

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