Conversation
…n splitBlockBefore() (llvm#178895)" This reverts commit ad8d534.
Member
|
@llvm/pr-subscribers-llvm-transforms Author: Mingjie Xu (Enna1) ChangesThis reverts commit ad8d534. LLVM Buildbot detected a failure, https://lab.llvm.org/buildbot/#/builders/210/builds/8229 Full diff: https://github.com/llvm/llvm-project/pull/179373.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 6472e1771ec73..68d1fd892402c 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -1054,6 +1054,50 @@ BasicBlock *llvm::SplitBlock(BasicBlock *Old, BasicBlock::iterator SplitPt,
return SplitBlockImpl(Old, SplitPt, DTU, /*DT=*/nullptr, LI, MSSAU, BBName);
}
+BasicBlock *llvm::splitBlockBefore(BasicBlock *Old, BasicBlock::iterator SplitPt,
+ DomTreeUpdater *DTU, LoopInfo *LI,
+ MemorySSAUpdater *MSSAU,
+ const Twine &BBName) {
+
+ BasicBlock::iterator SplitIt = SplitPt;
+ while (isa<PHINode>(SplitIt) || SplitIt->isEHPad())
+ ++SplitIt;
+ std::string Name = BBName.str();
+ BasicBlock *New = Old->splitBasicBlockBefore(
+ SplitIt, Name.empty() ? Old->getName() + ".split" : Name);
+
+ // The new block lives in whichever loop the old one did. This preserves
+ // LCSSA as well, because we force the split point to be after any PHI nodes.
+ if (LI)
+ if (Loop *L = LI->getLoopFor(Old))
+ L->addBasicBlockToLoop(New, *LI);
+
+ if (DTU) {
+ SmallVector<DominatorTree::UpdateType, 8> DTUpdates;
+ // New dominates Old. The predecessor nodes of the Old node dominate
+ // New node.
+ SmallPtrSet<BasicBlock *, 8> UniquePredecessorsOfOld;
+ DTUpdates.push_back({DominatorTree::Insert, New, Old});
+ DTUpdates.reserve(DTUpdates.size() + 2 * pred_size(New));
+ for (BasicBlock *PredecessorOfOld : predecessors(New))
+ if (UniquePredecessorsOfOld.insert(PredecessorOfOld).second) {
+ DTUpdates.push_back({DominatorTree::Insert, PredecessorOfOld, New});
+ DTUpdates.push_back({DominatorTree::Delete, PredecessorOfOld, Old});
+ }
+
+ DTU->applyUpdates(DTUpdates);
+
+ // Move MemoryAccesses still tracked in Old, but part of New now.
+ // Update accesses in successor blocks accordingly.
+ if (MSSAU) {
+ MSSAU->applyUpdates(DTUpdates, DTU->getDomTree());
+ if (VerifyMemorySSA)
+ MSSAU->getMemorySSA()->verifyMemorySSA();
+ }
+ }
+ return New;
+}
+
/// Update DominatorTree, LoopInfo, and LCCSA analysis information.
/// Invalidates DFS Numbering when DTU or DT is provided.
static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
@@ -1168,25 +1212,6 @@ static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
}
}
-BasicBlock *llvm::splitBlockBefore(BasicBlock *Old,
- BasicBlock::iterator SplitPt,
- DomTreeUpdater *DTU, LoopInfo *LI,
- MemorySSAUpdater *MSSAU,
- const Twine &BBName) {
- BasicBlock::iterator SplitIt = SplitPt;
- while (isa<PHINode>(SplitIt) || SplitIt->isEHPad())
- ++SplitIt;
- SmallVector<BasicBlock *, 4> Preds(predecessors(Old));
- BasicBlock *New = Old->splitBasicBlockBefore(
- SplitIt, BBName.isTriviallyEmpty() ? Old->getName() + ".split" : BBName);
-
- bool HasLoopExit = false;
- UpdateAnalysisInformation(Old, New, Preds, DTU, nullptr, LI, MSSAU, false,
- HasLoopExit);
-
- return New;
-}
-
/// Update the PHI nodes in OrigBB to include the values coming from NewBB.
/// This also updates AliasAnalysis, if available.
static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
diff --git a/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp b/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
index d5b4f6b6d6593..00d9e9ff81e05 100644
--- a/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
+++ b/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
@@ -378,31 +378,6 @@ define i32 @no_unreachable(i1 %cond) {
EXPECT_TRUE(DT.verify());
}
-TEST(BasicBlockUtils, splitBlockBefore) {
- LLVMContext C;
- std::unique_ptr<Module> M = parseIR(C, R"IR(
-define i32 @basic_func(i1 %cond) {
-entry:
- br i1 %cond, label %bb0, label %bb1
-bb0:
- br label %bb1
-bb1:
- %phi = phi i32 [ 0, %entry ], [ 1, %bb0 ]
- ret i32 %phi
-}
-)IR");
- Function *F = M->getFunction("basic_func");
- DominatorTree DT(*F);
- DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Eager);
- BasicBlock *EntryBB = &F->getEntryBlock();
- Instruction *TI = EntryBB->getTerminator();
-
- // Make sure the dominator tree is properly updated if calling this on the
- // entry block.
- splitBlockBefore(EntryBB, TI, &DTU, nullptr, nullptr);
- EXPECT_TRUE(DTU.getDomTree().verify());
-}
-
TEST(BasicBlockUtils, SplitBlockPredecessors) {
LLVMContext C;
std::unique_ptr<Module> M = parseIR(C, R"IR(
|
You can test this locally with the following command:git-clang-format --diff origin/main HEAD --extensions cpp -- llvm/lib/Transforms/Utils/BasicBlockUtils.cpp llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp --diff_from_common_commit
View the diff from clang-format here.diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 68d1fd892..b5c48bae2 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -1054,7 +1054,8 @@ BasicBlock *llvm::SplitBlock(BasicBlock *Old, BasicBlock::iterator SplitPt,
return SplitBlockImpl(Old, SplitPt, DTU, /*DT=*/nullptr, LI, MSSAU, BBName);
}
-BasicBlock *llvm::splitBlockBefore(BasicBlock *Old, BasicBlock::iterator SplitPt,
+BasicBlock *llvm::splitBlockBefore(BasicBlock *Old,
+ BasicBlock::iterator SplitPt,
DomTreeUpdater *DTU, LoopInfo *LI,
MemorySSAUpdater *MSSAU,
const Twine &BBName) {
|
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/10/builds/21802 Here is the relevant piece of the build log for the reference |
moar55
pushed a commit
to moar55/llvm-project
that referenced
this pull request
Feb 3, 2026
…n splitBlockBefore() (llvm#178895)" (llvm#179373) This reverts commit ad8d534. LLVM Buildbot detected a failure, https://lab.llvm.org/buildbot/#/builders/210/builds/8229
rishabhmadan19
pushed a commit
to rishabhmadan19/llvm-project
that referenced
this pull request
Feb 9, 2026
…n splitBlockBefore() (llvm#178895)" (llvm#179373) This reverts commit ad8d534. LLVM Buildbot detected a failure, https://lab.llvm.org/buildbot/#/builders/210/builds/8229
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This reverts commit ad8d534.
LLVM Buildbot detected a failure, https://lab.llvm.org/buildbot/#/builders/210/builds/8229