diff options
| -rw-r--r-- | llvm/lib/Transforms/Utils/LoopUtils.cpp | 32 | ||||
| -rw-r--r-- | llvm/test/Transforms/LoopSimplify/preserve-llvm-loop-metadata2.ll | 48 |
2 files changed, 0 insertions, 80 deletions
diff --git a/llvm/lib/Transforms/Utils/LoopUtils.cpp b/llvm/lib/Transforms/Utils/LoopUtils.cpp index 56b4c448c84..249869e1bde 100644 --- a/llvm/lib/Transforms/Utils/LoopUtils.cpp +++ b/llvm/lib/Transforms/Utils/LoopUtils.cpp @@ -74,41 +74,9 @@ bool llvm::formDedicatedExitBlocks(Loop *L, DominatorTree *DT, LoopInfo *LI, if (IsDedicatedExit) return false; - // With nested loops, the inner loop might exit to the header of an - // enclosing loop, and the in-loop-predecessor is a latch for that - // enclosing loop. If we insert a block between the latch and the header, - // that block becomes the new latch. Any loop metadata from the old latch - // needs to be moved to the new one. - MDNode *OuterLoopMD = nullptr; - - // If the exit block is a header of a different loop, get that loop's - // metadata before we split the block. - if (LI->isLoopHeader(BB)) - OuterLoopMD = LI->getLoopFor(BB)->getLoopID(); - auto *NewExitBB = SplitBlockPredecessors( BB, InLoopPredecessors, ".loopexit", DT, LI, nullptr, PreserveLCSSA); - // If OuterLoopMD is non-null, we know that the exit block BB is a - // loop header for a different loop, with metadata on its back edges. - // If NewExitBB is a member of that loop, then NewExitBB is a latch, - // and the loop's metadata needs to be copied to NewExitBB. - if (NewExitBB && OuterLoopMD && - LI->getLoopFor(NewExitBB) == LI->getLoopFor(BB)) { - // The preds of NewExitBB are all former latches of the outer loop. - // Remove their metadata. - for (auto *PredLoopBB : InLoopPredecessors) { - Instruction *TI = PredLoopBB->getTerminator(); - // All the latches should have the same metadata (ensured by - // getLoopID()). - assert(TI->getMetadata(LLVMContext::MD_loop) == OuterLoopMD && - "exit edge to other loop doesn't contain expected metadata"); - TI->setMetadata(LLVMContext::MD_loop, nullptr); - } - NewExitBB->getTerminator()->setMetadata(LLVMContext::MD_loop, - OuterLoopMD); - } - if (!NewExitBB) LLVM_DEBUG( dbgs() << "WARNING: Can't create a dedicated exit block for loop: " diff --git a/llvm/test/Transforms/LoopSimplify/preserve-llvm-loop-metadata2.ll b/llvm/test/Transforms/LoopSimplify/preserve-llvm-loop-metadata2.ll deleted file mode 100644 index 2e391ce6dea..00000000000 --- a/llvm/test/Transforms/LoopSimplify/preserve-llvm-loop-metadata2.ll +++ /dev/null @@ -1,48 +0,0 @@ -; RUN: opt -S -loop-simplify < %s | FileCheck %s - -; Two-loop nest with llvm.loop metadata on each loop. -; inner.header exits to outer.header. inner.header is a latch for the outer -; loop, and contains the outer loop's metadata. -; After loop-simplify, a new block "outer.header.loopexit" is created between -; inner.header and outer.header. The metadata from inner.header must be moved -; to the new block, as the new block becomes the outer loop latch. -; The metadata on the inner loop's latch should be untouched. - -; CHECK: outer.header.loopexit: -; CHECK-NEXT: llvm.loop [[UJAMTAG:.*]] -; CHECK-NOT: br i1 {{.*}}, label {{.*}}, label %outer.header.loopexit, !llvm.loop -; CHECK: br label %inner.header, !llvm.loop [[UNROLLTAG:.*]] - -; CHECK: distinct !{[[UJAMTAG]], [[UJAM:.*]]} -; CHECK: [[UJAM]] = !{!"llvm.loop.unroll_and_jam.count", i32 17} -; CHECK: distinct !{[[UNROLLTAG]], [[UNROLL:.*]]} -; CHECK: [[UNROLL]] = !{!"llvm.loop.unroll.count", i32 1} - - -define dso_local void @loopnest() local_unnamed_addr #0 { -entry: - br label %outer.header - -outer.header: ; preds = %inner.header, %entry - %ii.0 = phi i64 [ 2, %entry ], [ %add, %inner.header ] - %cmp = icmp ult i64 %ii.0, 64 - br i1 %cmp, label %inner.header, label %outer.header.cleanup - -outer.header.cleanup: ; preds = %outer.header - ret void - -inner.header: ; preds = %outer.header, %inner.body - %j.0 = phi i64 [ %add10, %inner.body ], [ %ii.0, %outer.header ] - %add = add nuw nsw i64 %ii.0, 16 - %cmp2 = icmp ult i64 %j.0, %add - br i1 %cmp2, label %inner.body, label %outer.header, !llvm.loop !2 - -inner.body: ; preds = %inner.header - %add10 = add nuw nsw i64 %j.0, 1 - br label %inner.header, !llvm.loop !4 -} - -!2 = distinct !{!2, !3} -!3 = !{!"llvm.loop.unroll_and_jam.count", i32 17} -!4 = distinct !{!4, !5} -!5 = !{!"llvm.loop.unroll.count", i32 1} |
