Eliminate the explicit opcode field in ConstantExpr, using the SubclassData field to hold it instead.  This shrinks memory usage for 176.gcc from 57628728 to 57598144 bytes, a small reduction of about 30K.
Eliminate the explicit opcode field in ConstantExpr, using the SubclassData
field to hold it instead.  This shrinks memory usage for 176.gcc from
57628728 to 57598144 bytes, a small reduction of about 30K.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@20047 91177308-0d34-0410-b5e6-96231b3b80d8

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