From 3472ae1e7b0f38c4ac0802ffc2900f71a5470c3b Mon Sep 17 00:00:00 2001 From: Eric Christopher Date: Thu, 10 Dec 2009 00:25:41 +0000 Subject: [PATCH] Make sure the immediate dominator isn't NULL through iterations of the loop. We could get to this condition via indirect branches. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91009 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/LICM.cpp | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp index 5511387c8da..42a8fdc6aa8 100644 --- a/lib/Transforms/Scalar/LICM.cpp +++ b/lib/Transforms/Scalar/LICM.cpp @@ -160,16 +160,17 @@ namespace { // Because the exit block is not in the loop, we know we have to get _at // least_ its immediate dominator. - do { - // Get next Immediate Dominator. - IDom = IDom->getIDom(); - + IDom = IDom->getIDom(); + + while (IDom && IDom != BlockInLoopNode) { // If we have got to the header of the loop, then the instructions block // did not dominate the exit node, so we can't hoist it. if (IDom->getBlock() == LoopHeader) return false; - } while (IDom != BlockInLoopNode); + // Get next Immediate Dominator. + IDom = IDom->getIDom(); + }; return true; }