diff options
Diffstat (limited to 'lib/Transforms/Utils/LoopUnroll.cpp')
| -rw-r--r-- | lib/Transforms/Utils/LoopUnroll.cpp | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/lib/Transforms/Utils/LoopUnroll.cpp b/lib/Transforms/Utils/LoopUnroll.cpp index e39ade523714..a7590fc32545 100644 --- a/lib/Transforms/Utils/LoopUnroll.cpp +++ b/lib/Transforms/Utils/LoopUnroll.cpp @@ -711,7 +711,7 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI, auto setDest = [LoopExit, ContinueOnTrue](BasicBlock *Src, BasicBlock *Dest, ArrayRef<BasicBlock *> NextBlocks, - BasicBlock *CurrentHeader, + BasicBlock *BlockInLoop, bool NeedConditional) { auto *Term = cast<BranchInst>(Src->getTerminator()); if (NeedConditional) { @@ -723,7 +723,9 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI, if (Dest != LoopExit) { BasicBlock *BB = Src; for (BasicBlock *Succ : successors(BB)) { - if (Succ == CurrentHeader) + // Preserve the incoming value from BB if we are jumping to the block + // in the current loop. + if (Succ == BlockInLoop) continue; for (PHINode &Phi : Succ->phis()) Phi.removeIncomingValue(BB, false); @@ -794,7 +796,7 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI, // unconditional branch for some iterations. NeedConditional = false; - setDest(Headers[i], Dest, Headers, Headers[i], NeedConditional); + setDest(Headers[i], Dest, Headers, HeaderSucc[i], NeedConditional); } // Set up latches to branch to the new header in the unrolled iterations or @@ -868,7 +870,7 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI, assert(!DT || !UnrollVerifyDomtree || DT->verify(DominatorTree::VerificationLevel::Fast)); - DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Eager); + DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Lazy); // Merge adjacent basic blocks, if possible. for (BasicBlock *Latch : Latches) { BranchInst *Term = dyn_cast<BranchInst>(Latch->getTerminator()); @@ -888,6 +890,8 @@ LoopUnrollResult llvm::UnrollLoop(Loop *L, UnrollLoopOptions ULO, LoopInfo *LI, } } } + // Apply updates to the DomTree. + DT = &DTU.getDomTree(); // At this point, the code is well formed. We now simplify the unrolled loop, // doing constant propagation and dead code elimination as we go. |