[LCSSA] Add expensive verification of LCSSA form for sub-loops.
This assertion makes sure all sub-loops are in LCSSA form before
bringing their parent in LCSSA form. This precondition was added to
formLCSSA in D56848.
Reviewers: davide, efriedma, mzolotukhin
Reviewed By: davide
Differential Revision: https://reviews.llvm.org/D56921
llvm-svn: 352958
diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp
index 3a08977..2706766 100644
--- a/llvm/lib/Transforms/Utils/LCSSA.cpp
+++ b/llvm/lib/Transforms/Utils/LCSSA.cpp
@@ -305,6 +305,12 @@
ScalarEvolution *SE) {
bool Changed = false;
+#ifdef EXPENSIVE_CHECKS
+ // Verify all sub-loops are in LCSSA form already.
+ for (Loop *SubLoop: L)
+ assert(SubLoop->isRecursivelyLCSSAForm(DT, *LI) && "Subloop not in LCSSA!");
+#endif
+
SmallVector<BasicBlock *, 8> ExitBlocks;
L.getExitBlocks(ExitBlocks);
if (ExitBlocks.empty())