-
-bool RaiseAllocations::doInitialization(Module *M) {
- SymbolTable *ST = M->getSymbolTable();
- if (!ST) return false;
-
- // If the module has a symbol table, they might be referring to the malloc
- // and free functions. If this is the case, grab the method pointers that
- // the module is using.
- //
- // Lookup %malloc and %free in the symbol table, for later use. If they
- // don't exist, or are not external, we do not worry about converting calls
- // to that function into the appropriate instruction.
- //
- const PointerType *MallocType = // Get the type for malloc
- PointerType::get(MethodType::get(PointerType::get(Type::SByteTy),
- vector<const Type*>(1, Type::UIntTy), false));
- MallocMeth = cast_or_null<Method>(ST->lookup(MallocType, "malloc"));
- if (MallocMeth && !MallocMeth->isExternal())
- MallocMeth = 0; // Don't mess with locally defined versions of the fn
-
- const PointerType *FreeType = // Get the type for free
- PointerType::get(MethodType::get(Type::VoidTy,
- vector<const Type*>(1, PointerType::get(Type::SByteTy)), false));
- FreeMeth = cast_or_null<Method>(ST->lookup(FreeType, "free"));
- if (FreeMeth && !FreeMeth->isExternal())
- FreeMeth = 0; // Don't mess with locally defined versions of the fn
-
- return false;
-}
-
-// doOneCleanupPass - Do one pass over the input method, fixing stuff up.
-//
-bool RaiseAllocations::runOnBasicBlock(BasicBlock *BB) {
- bool Changed = false;
- BasicBlock::InstListType &BIL = BB->getInstList();
-
- for (BasicBlock::iterator BI = BB->begin(); BI != BB->end();) {
- Instruction *I = *BI;
-
- if (CallInst *CI = dyn_cast<CallInst>(I)) {
- if (CI->getCalledValue() == MallocMeth) { // Replace call to malloc?
- const Type *PtrSByte = PointerType::get(Type::SByteTy);
- MallocInst *MallocI = new MallocInst(PtrSByte, CI->getOperand(1),
- CI->getName());
- CI->setName("");
- ReplaceInstWithInst(BIL, BI, MallocI);
- Changed = true;
- continue; // Skip the ++BI
- } else if (CI->getCalledValue() == FreeMeth) { // Replace call to free?
- ReplaceInstWithInst(BIL, BI, new FreeInst(CI->getOperand(1)));
- Changed = true;
- continue; // Skip the ++BI
- }
- }
-
- ++BI;
- }
-
- return Changed;
-}