This change is to fix rdar://
12571717 which is about assertion in Reassociate pass.
The assertion is trigged when the Reassociater tries to transform expression
... + 2 * n * 3 + 2 * m + ...
into:
... + 2 * (n*3 + m).
In the process of the transformation, a helper routine folds the constant 2*3 into 6,
confusing optimizer which is trying the to eliminate the common factor 2, and cannot
find 2 any more.
Review is pending. But I'd like commit first in order to help those who are waiting
for this fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167740
91177308-0d34-0410-b5e6-
96231b3b80d8