[llvm] r267671 - [Cloning] cloneLoopWithPreheader(): add assert to ensure no sub-loops

[Vaivaswatha Nagaraj via llvm-commits]

Author: vaivaswatha
Date: Wed Apr 27 00:25:09 2016
New Revision: 267671

URL: http://llvm.org/viewvc/llvm-project?rev=267671&view=rev
Log:
[Cloning] cloneLoopWithPreheader(): add assert to ensure no sub-loops

Summary:
cloneLoopWithPreheader() does not update LoopInfo for sub-loop of
the original loop being cloned. Add assert to ensure no sub-loops for loop being cloned.

Reviewers: anemet, ashutosh.nema, hfinkel

Subscribers: mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D15922

Modified:
    llvm/trunk/include/llvm/Transforms/Utils/Cloning.h
    llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp

Modified: llvm/trunk/include/llvm/Transforms/Utils/Cloning.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/Cloning.h?rev=267671&r1=267670&r2=267671&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/Cloning.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/Cloning.h Wed Apr 27 00:25:09 2016
@@ -221,6 +221,7 @@ bool InlineFunction(CallSite CS, InlineF
 ///
 /// Updates LoopInfo and DominatorTree assuming the loop is dominated by block
 /// \p LoopDomBB.  Insert the new blocks before block specified in \p Before.
+/// Note: Only innermost loops are supported.
 Loop *cloneLoopWithPreheader(BasicBlock *Before, BasicBlock *LoopDomBB,
                              Loop *OrigLoop, ValueToValueMapTy &VMap,
                              const Twine &NameSuffix, LoopInfo *LI,

Modified: llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp?rev=267671&r1=267670&r2=267671&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp Wed Apr 27 00:25:09 2016
@@ -672,6 +672,8 @@ Loop *llvm::cloneLoopWithPreheader(Basic
                                    const Twine &NameSuffix, LoopInfo *LI,
                                    DominatorTree *DT,
                                    SmallVectorImpl<BasicBlock *> &Blocks) {
+  assert(OrigLoop->getSubLoops().empty() && 
+         "Loop to be cloned cannot have inner loop");
   Function *F = OrigLoop->getHeader()->getParent();
   Loop *ParentLoop = OrigLoop->getParentLoop();