RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2025-04-17 21:42:12 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Delay dominator updation while cloning loop.

Browse Source 
Summary:
Dominator updation fails for a loop inserted with a new basicblock.

A block required by DT to set the IDom might not have been cloned yet. This is because there is no predefined ordering of loop blocks (except for the header block which should be the first block in the list).

The patch first creates DT nodes for the cloned blocks and then separately updates the DT in a follow-on loop.

Reviewers: anemet, dberlin

Subscribers: dberlin, llvm-commits

Differential Revision: http://reviews.llvm.org/D20899

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272479 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Vikram TV 2016-06-11 16:41:10 +00:00
parent fd46fc3322
commit d1fd57765b
1 changed files with 9 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
lib/Transforms/Utils/CloneFunction.cpp
View File

@ -688,13 +688,19 @@ Loop *llvm::cloneLoopWithPreheader(BasicBlock *Before, BasicBlock *LoopDomBB,
// Update LoopInfo. // Update LoopInfo.
NewLoop->addBasicBlockToLoop(NewBB, *LI); NewLoop->addBasicBlockToLoop(NewBB, *LI);
// Update DominatorTree. // Add DominatorTree node. After seeing all blocks, update to correct IDom.
BasicBlock *IDomBB = DT->getNode(BB)->getIDom()->getBlock(); DT->addNewBlock(NewBB, NewPH);
DT->addNewBlock(NewBB, cast<BasicBlock>(VMap[IDomBB]));
Blocks.push_back(NewBB); Blocks.push_back(NewBB);
} }
for (BasicBlock *BB : OrigLoop->getBlocks()) {
// Update DominatorTree.
BasicBlock *IDomBB = DT->getNode(BB)->getIDom()->getBlock();
DT->changeImmediateDominator(cast<BasicBlock>(VMap[BB]),
cast<BasicBlock>(VMap[IDomBB]));
}
// Move them physically from the end of the block list. // Move them physically from the end of the block list.
F->getBasicBlockList().splice(Before->getIterator(), F->getBasicBlockList(), F->getBasicBlockList().splice(Before->getIterator(), F->getBasicBlockList(),
NewPH); NewPH);