diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp index 7644c1e4196..0edf6a76a62 100644 --- a/lib/VMCore/ConstantFold.cpp +++ b/lib/VMCore/ConstantFold.cpp @@ -141,12 +141,30 @@ Constant *ConstantFoldGetElementPtr(const Constant *C, // FIXME: Implement folding of GEP constant exprs the same as instcombine does - // Implement folding of: - // int* getelementptr ([2 x int]* cast ([3 x int]* %X to [2 x int]*), - // long 0, long 0) - // To: int* getelementptr ([3 x int]* %X, long 0, long 0) - // - if (const ConstantExpr *CE = dyn_cast(C)) + if (const ConstantExpr *CE = dyn_cast(C)) { + // Implement folding of: + // void ()** getelementptr (%struct..TorRec* getelementptr + // ([N x %struct..TorRec]* %llvm.global_dtors, long 0, long 0), + // long 0, ubyte 1) + // Into: + // %struct..TorRec* getelementptr ([N x %struct..TorRec]* + // %llvm.global_dtors, long 0, long 0, ubyte 1) + // + if (CE->getOpcode() == Instruction::GetElementPtr) + if (IdxList[0] == Constant::getNullValue(Type::LongTy)) { + std::vector NewIndices; + NewIndices.reserve(IdxList.size() + CE->getNumOperands()); + for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i) + NewIndices.push_back(cast(CE->getOperand(i))); + NewIndices.insert(NewIndices.end(), IdxList.begin()+1, IdxList.end()); + return ConstantExpr::getGetElementPtr(CE->getOperand(0), NewIndices); + } + + // Implement folding of: + // int* getelementptr ([2 x int]* cast ([3 x int]* %X to [2 x int]*), + // long 0, long 0) + // To: int* getelementptr ([3 x int]* %X, long 0, long 0) + // if (CE->getOpcode() == Instruction::Cast && IdxList.size() > 1 && IdxList[0]->isNullValue()) if (const PointerType *SPT = @@ -157,6 +175,7 @@ Constant *ConstantFoldGetElementPtr(const Constant *C, if (CAT->getElementType() == SAT->getElementType()) return ConstantExpr::getGetElementPtr( (Constant*)CE->getOperand(0), IdxList); + } return 0; }