diff --git a/include/llvm/Transforms/Utils/Local.h b/include/llvm/Transforms/Utils/Local.h index 103d4cda41a..0b8147e76df 100644 --- a/include/llvm/Transforms/Utils/Local.h +++ b/include/llvm/Transforms/Utils/Local.h @@ -74,6 +74,14 @@ bool RecursivelyDeleteTriviallyDeadInstructions(Value *V); /// too, recursively. Return true if the PHI node is actually deleted. bool RecursivelyDeleteDeadPHINode(PHINode *PN); + +/// SimplifyInstructionsInBlock - Scan the specified basic block and try to +/// simplify any instructions in it and recursively delete dead instructions. +/// +/// This returns true if it changed the code, note that it can delete +/// instructions in other blocks as well in this block. +bool SimplifyInstructionsInBlock(BasicBlock *BB, const TargetData *TD = 0); + //===----------------------------------------------------------------------===// // Control Flow Graph Restructuring. // diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp index 1a7d27ad45c..90e929e127e 100644 --- a/lib/Transforms/Utils/Local.cpp +++ b/lib/Transforms/Utils/Local.cpp @@ -335,6 +335,30 @@ llvm::RecursivelyDeleteDeadPHINode(PHINode *PN) { return Changed; } +/// SimplifyInstructionsInBlock - Scan the specified basic block and try to +/// simplify any instructions in it and recursively delete dead instructions. +/// +/// This returns true if it changed the code, note that it can delete +/// instructions in other blocks as well in this block. +bool llvm::SimplifyInstructionsInBlock(BasicBlock *BB, const TargetData *TD) { + bool MadeChange = false; + for (BasicBlock::iterator BI = BB->begin(), E = BB->end(); BI != E; ) { + Instruction *Inst = BI++; + + if (Value *V = SimplifyInstruction(Inst, TD)) { + WeakVH BIHandle(BI); + ReplaceAndSimplifyAllUses(Inst, V, TD); + MadeChange = true; + if (BIHandle == 0) + BI = BB->begin(); + continue; + } + + MadeChange |= RecursivelyDeleteTriviallyDeadInstructions(Inst); + } + return MadeChange; +} + //===----------------------------------------------------------------------===// // Control Flow Graph Restructuring. //