Iterate over all store memory accesses and check for valid binary reduction
candidate loads by following the operands of the stored value. For each
candidate pair we check if they have the same base address and there are no
other accesses which may overlap with them. This ensures that no intermediate
value can escape into other memory locations or is overwritten at some point.
+ 17 test cases for reduction detection and reduction dependency modeling
llvm-svn: 211957
Johannes Doerfert