[InstCombine][X86] Add tests showing missed opportunities to simplify PMULUDQ/PMULDQ inputs.

PMULUDQ/PMULDQ - only the even elements (0, 2, 4, 6) of the vXi32 inputs are required.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290502 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed