[ScalarizeMaskedMemIntrin] Only set the ModifiedDT flag if new basic blocks were added.
[ScalarizeMaskedMemIntrin] Only set the ModifiedDT flag if new basic blocks were added.

There are special cases in the scalarization for constant masks. If we hit one of the special cases we don't need to reset the iteration.

Noticed while starting work on adding expandload/compressstore to this pass.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@355754 91177308-0d34-0410-b5e6-96231b3b80d8

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