Paul Redmond 6ce33a6ae9 Do not vectorize loops with subtraction reductions
Since subtraction does not commute the loop vectorizer incorrectly vectorizes
reductions such as x = A[i] - x.

Disabling for now.

llvm-svn: 171537
2013-01-04 22:10:16 +00:00
..
2012-11-16 20:51:32 +00:00