diff options
| -rw-r--r-- | llvm/include/llvm/Transforms/IPO/Attributor.h | 17 | ||||
| -rw-r--r-- | llvm/lib/Transforms/IPO/Attributor.cpp | 20 |
2 files changed, 37 insertions, 0 deletions
diff --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h index bea369a6b51..54c996e0da5 100644 --- a/llvm/include/llvm/Transforms/IPO/Attributor.h +++ b/llvm/include/llvm/Transforms/IPO/Attributor.h @@ -675,6 +675,15 @@ struct Attributor { void identifyDefaultAbstractAttributes( Function &F, DenseSet<const char *> *Whitelist = nullptr); + /// Record that \p I is deleted after information was manifested. + void deleteAfterManifest(Instruction &I) { ToBeDeletedInsts.insert(&I); } + + /// Record that \p BB is deleted after information was manifested. + void deleteAfterManifest(BasicBlock &BB) { ToBeDeletedBlocks.insert(&BB); } + + /// Record that \p F is deleted after information was manifested. + void deleteAfterManifest(Function &F) { ToBeDeletedFunctions.insert(&F); } + /// Return true if \p AA (or its context instruction) is assumed dead. /// /// If \p LivenessAA is not provided it is queried. @@ -765,6 +774,14 @@ private: /// The information cache that holds pre-processed (LLVM-IR) information. InformationCache &InfoCache; + + /// Functions, blocks, and instructions we delete after manifest is done. + /// + ///{ + SmallPtrSet<Function *, 8> ToBeDeletedFunctions; + SmallPtrSet<BasicBlock *, 8> ToBeDeletedBlocks; + SmallPtrSet<Instruction *, 8> ToBeDeletedInsts; + ///} }; /// An interface to query the internal state of an abstract attribute. diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp index a6e8e528fd0..a2d470affc0 100644 --- a/llvm/lib/Transforms/IPO/Attributor.cpp +++ b/llvm/lib/Transforms/IPO/Attributor.cpp @@ -2641,6 +2641,26 @@ ChangeStatus Attributor::run() { assert( NumFinalAAs == AllAbstractAttributes.size() && "Expected the final number of abstract attributes to remain unchanged!"); + + // Delete stuff at the end to avoid invalid references and a nice order. + LLVM_DEBUG(dbgs() << "\n[Attributor] Delete " << ToBeDeletedFunctions.size() + << " functions and " << ToBeDeletedBlocks.size() + << " blocks and " << ToBeDeletedInsts.size() + << " instructions\n"); + for (Instruction *I : ToBeDeletedInsts) { + if (I->hasNUsesOrMore(1)) + I->replaceAllUsesWith(UndefValue::get(I->getType())); + I->eraseFromParent(); + } + for (BasicBlock *BB : ToBeDeletedBlocks) { + // TODO: Check if we need to replace users (PHIs, indirect branches?) + BB->eraseFromParent(); + } + for (Function *Fn : ToBeDeletedFunctions) { + Fn->replaceAllUsesWith(UndefValue::get(Fn->getType())); + Fn->eraseFromParent(); + } + return ManifestChange; } |
