Constants with multiple encodings (ARM):

An alternative syntax is available for a modified immediate constant that permits the programmer to specify
the encoding directly. In this syntax, #<const> is instead written as #<byte>,#<rot>, where:

    <byte> is the numeric value of abcdefgh, in the range 0-255
    <rot> is twice the numeric value of rotation, an even number in the range 0-30.

llvm-svn: 128897