[PATCH] SROA: Don't insert instructions before a PHI

[Chandler Carruth]

Minor tweaks to the test below, thanks!

================
Comment at: test/Transforms/SROA/phi-and-select.ll:572
@@ +571,3 @@
+
+define void @PR20822() {
+entry:
----------------
Need a CHECK-LABEL here.

I would also summarize the salient point of the test -- that we have a foldable PHI feeding a speculatable PHI which requires the rewriting of the speculated PHI to handle insertion when the incoming pointer is itself from a PHI node.

http://reviews.llvm.org/D5141