From 5dd55e8405d66842219883a55563ec45cc010da4 Mon Sep 17 00:00:00 2001 From: Michael Kuperstein Date: Thu, 26 Jan 2017 01:04:11 +0000 Subject: [LoopUnroll] Properly update loopinfo for runtime unrolling by 2 Even when we don't create a remainder loop (that is, when we unroll by 2), we may duplicate nested loops into the remainder. This is complicated by the fact the remainder may itself be either inserted into an outer loop, or at the top level. In the latter case, we may need to create new top-level loops. Differential Revision: https://reviews.llvm.org/D29156 llvm-svn: 293124 --- llvm/lib/Transforms/Utils/LoopUnroll.cpp | 11 +++++++---- llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp | 15 ++++++++++----- 2 files changed, 17 insertions(+), 9 deletions(-) (limited to 'llvm/lib/Transforms/Utils') diff --git a/llvm/lib/Transforms/Utils/LoopUnroll.cpp b/llvm/lib/Transforms/Utils/LoopUnroll.cpp index 7cd69d2b847..5c3c94008d3 100644 --- a/llvm/lib/Transforms/Utils/LoopUnroll.cpp +++ b/llvm/lib/Transforms/Utils/LoopUnroll.cpp @@ -199,11 +199,14 @@ const Loop* llvm::addClonedBlockToLoopInfo(BasicBlock *OriginalBB, assert(OriginalBB == OldLoop->getHeader() && "Header should be first in RPO"); + NewLoop = new Loop(); Loop *NewLoopParent = NewLoops.lookup(OldLoop->getParentLoop()); - assert(NewLoopParent && - "Expected parent loop before sub-loop in RPO"); - NewLoop = new Loop; - NewLoopParent->addChildLoop(NewLoop); + + if (NewLoopParent) + NewLoopParent->addChildLoop(NewLoop); + else + LI->addTopLevelLoop(NewLoop); + NewLoop->addBasicBlockToLoop(ClonedBB, *LI); return OldLoop; } else { diff --git a/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp b/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp index d5d54cf1d84..8406c563a9c 100644 --- a/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp +++ b/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp @@ -311,17 +311,22 @@ static void CloneLoopBlocks(Loop *L, Value *NewIter, } NewLoopsMap NewLoops; - NewLoops[L] = NewLoop; + if (NewLoop) + NewLoops[L] = NewLoop; + else if (ParentLoop) + NewLoops[L] = ParentLoop; + // For each block in the original loop, create a new copy, // and update the value map with the newly created values. for (LoopBlocksDFS::RPOIterator BB = BlockBegin; BB != BlockEnd; ++BB) { BasicBlock *NewBB = CloneBasicBlock(*BB, VMap, "." + suffix, F); NewBlocks.push_back(NewBB); - - if (NewLoop) { + + // If we're unrolling the outermost loop, there's no remainder loop, + // and this block isn't in a nested loop, then the new block is not + // in any loop. Otherwise, add it to loopinfo. + if (CreateRemainderLoop || LI->getLoopFor(*BB) != L || ParentLoop) addClonedBlockToLoopInfo(*BB, NewBB, LI, NewLoops); - } else if (ParentLoop) - ParentLoop->addBasicBlockToLoop(NewBB, *LI); VMap[*BB] = NewBB; if (Header == *BB) { -- cgit v1.2.3