on the size of the extraction and its position in the 64 bit word.
This patch allows support of the dext transformations with mips64 direct
object output.
0 <= msb < 32 0 <= lsb < 32 0 <= pos < 32 1 <= size <= 32
DINS
The field is entirely contained in the right-most word of the doubleword
32 <= msb < 64 0 <= lsb < 32 0 <= pos < 32 2 <= size <= 64
DINSM
The field straddles the words of the doubleword
32 <= msb < 64 32 <= lsb < 64 32 <= pos < 64 1 <= size <= 32
DINSU
The field is entirely contained in the left-most word of the doubleword
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163010 91177308-0d34-0410-b5e6-96231b3b80d8
