diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp index e249421a1f3..a241960b374 100644 --- a/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/lib/Analysis/ScalarEvolutionExpander.cpp @@ -185,14 +185,21 @@ Value *SCEVExpander::visitAddRecExpr(SCEVAddRecExpr *S) { Loop *InsertPtLoop = LI.getLoopFor(MulInsertPt->getParent()); if (InsertPtLoop != L && InsertPtLoop && L->contains(InsertPtLoop->getHeader())) { - while (InsertPtLoop != L) { + do { // If we cannot hoist the multiply out of this loop, don't. if (!InsertPtLoop->isLoopInvariant(F)) break; - // Otherwise, move the insert point to the preheader of the loop. - MulInsertPt = InsertPtLoop->getLoopPreheader()->getTerminator(); + BasicBlock *InsertPtLoopPH = InsertPtLoop->getLoopPreheader(); + + // If this loop hasn't got a preheader, we aren't able to hoist the + // multiply. + if (!InsertPtLoopPH) + break; + + // Otherwise, move the insert point to the preheader. + MulInsertPt = InsertPtLoopPH->getTerminator(); InsertPtLoop = InsertPtLoop->getParentLoop(); - } + } while (InsertPtLoop != L); } return InsertBinop(Instruction::Mul, I, F, MulInsertPt);