| //===- ReadInst.cpp - Code to read an instruction from bytecode -------------=== |
| // |
| // This file defines the mechanism to read an instruction from a bytecode |
| // stream. |
| // |
| // Note that this library should be as fast as possible, reentrant, and |
| // threadsafe!! |
| // |
| // TODO: Change from getValue(Raw.Arg1) etc, to getArg(Raw, 1) |
| // Make it check type, so that casts are checked. |
| // |
| //===------------------------------------------------------------------------=== |
| |
| #include "llvm/iOther.h" |
| #include "llvm/iTerminators.h" |
| #include "llvm/iMemory.h" |
| #include "llvm/DerivedTypes.h" |
| #include "ReaderInternals.h" |
| |
| bool BytecodeParser::ParseRawInst(const uchar *&Buf, const uchar *EndBuf, |
| RawInst &Result) { |
| unsigned Op, Typ; |
| if (read(Buf, EndBuf, Op)) return failure(true); |
| |
| Result.NumOperands = Op >> 30; |
| Result.Opcode = (Op >> 24) & 63; |
| |
| switch (Result.NumOperands) { |
| case 1: |
| Result.Ty = getType((Op >> 12) & 4095); |
| Result.Arg1 = Op & 4095; |
| if (Result.Arg1 == 4095) // Handle special encoding for 0 operands... |
| Result.NumOperands = 0; |
| break; |
| case 2: |
| Result.Ty = getType((Op >> 16) & 255); |
| Result.Arg1 = (Op >> 8 ) & 255; |
| Result.Arg2 = (Op >> 0 ) & 255; |
| break; |
| case 3: |
| Result.Ty = getType((Op >> 18) & 63); |
| Result.Arg1 = (Op >> 12) & 63; |
| Result.Arg2 = (Op >> 6 ) & 63; |
| Result.Arg3 = (Op >> 0 ) & 63; |
| break; |
| case 0: |
| Buf -= 4; // Hrm, try this again... |
| if (read_vbr(Buf, EndBuf, Result.Opcode)) return failure(true); |
| if (read_vbr(Buf, EndBuf, Typ)) return failure(true); |
| Result.Ty = getType(Typ); |
| if (read_vbr(Buf, EndBuf, Result.NumOperands)) return failure(true); |
| |
| switch (Result.NumOperands) { |
| case 0: |
| cerr << "Zero Arg instr found!\n"; |
| return failure(true); // This encoding is invalid! |
| case 1: |
| if (read_vbr(Buf, EndBuf, Result.Arg1)) return failure(true); |
| break; |
| case 2: |
| if (read_vbr(Buf, EndBuf, Result.Arg1) || |
| read_vbr(Buf, EndBuf, Result.Arg2)) return failure(true); |
| break; |
| case 3: |
| if (read_vbr(Buf, EndBuf, Result.Arg1) || |
| read_vbr(Buf, EndBuf, Result.Arg2) || |
| read_vbr(Buf, EndBuf, Result.Arg3)) return failure(true); |
| break; |
| default: |
| if (read_vbr(Buf, EndBuf, Result.Arg1) || |
| read_vbr(Buf, EndBuf, Result.Arg2)) return failure(true); |
| |
| // Allocate a vector to hold arguments 3, 4, 5, 6 ... |
| Result.VarArgs = new vector<unsigned>(Result.NumOperands-2); |
| for (unsigned a = 0; a < Result.NumOperands-2; a++) |
| if (read_vbr(Buf, EndBuf, (*Result.VarArgs)[a])) return failure(true); |
| break; |
| } |
| if (align32(Buf, EndBuf)) return failure(true); |
| break; |
| } |
| |
| #if 0 |
| cerr << "NO: " << Result.NumOperands << " opcode: " << Result.Opcode |
| << " Ty: " << Result.Ty->getDescription() << " arg1: " << Result.Arg1 |
| << " arg2: " << Result.Arg2 << " arg3: " << Result.Arg3 << endl; |
| #endif |
| return false; |
| } |
| |
| |
| bool BytecodeParser::ParseInstruction(const uchar *&Buf, const uchar *EndBuf, |
| Instruction *&Res) { |
| RawInst Raw; |
| if (ParseRawInst(Buf, EndBuf, Raw)) return failure(true); |
| |
| if (Raw.Opcode >= Instruction::FirstUnaryOp && |
| Raw.Opcode < Instruction::NumUnaryOps && Raw.NumOperands == 1) { |
| Res = UnaryOperator::create((Instruction::UnaryOps)Raw.Opcode, |
| getValue(Raw.Ty,Raw.Arg1)); |
| return false; |
| } else if (Raw.Opcode >= Instruction::FirstBinaryOp && |
| Raw.Opcode < Instruction::NumBinaryOps && Raw.NumOperands == 2) { |
| Res = BinaryOperator::create((Instruction::BinaryOps)Raw.Opcode, |
| getValue(Raw.Ty, Raw.Arg1), |
| getValue(Raw.Ty, Raw.Arg2)); |
| return false; |
| } |
| |
| Value *V; |
| switch (Raw.Opcode) { |
| case Instruction::Cast: |
| Res = new CastInst(getValue(Raw.Ty, Raw.Arg1), getType(Raw.Arg2)); |
| return false; |
| |
| case Instruction::PHINode: { |
| PHINode *PN = new PHINode(Raw.Ty); |
| switch (Raw.NumOperands) { |
| case 0: |
| case 1: |
| case 3: cerr << "Invalid phi node encountered!\n"; |
| delete PN; |
| return failure(true); |
| case 2: PN->addIncoming(getValue(Raw.Ty, Raw.Arg1), |
| cast<BasicBlock>(getValue(Type::LabelTy,Raw.Arg2))); |
| break; |
| default: |
| PN->addIncoming(getValue(Raw.Ty, Raw.Arg1), |
| cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg2))); |
| if (Raw.VarArgs->size() & 1) { |
| cerr << "PHI Node with ODD number of arguments!\n"; |
| delete PN; |
| return failure(true); |
| } else { |
| vector<unsigned> &args = *Raw.VarArgs; |
| for (unsigned i = 0; i < args.size(); i+=2) |
| PN->addIncoming(getValue(Raw.Ty, args[i]), |
| cast<BasicBlock>(getValue(Type::LabelTy, args[i+1]))); |
| } |
| delete Raw.VarArgs; |
| break; |
| } |
| Res = PN; |
| return false; |
| } |
| |
| case Instruction::Shl: |
| case Instruction::Shr: |
| Res = new ShiftInst((Instruction::OtherOps)Raw.Opcode, |
| getValue(Raw.Ty, Raw.Arg1), |
| getValue(Type::UByteTy, Raw.Arg2)); |
| return false; |
| case Instruction::Ret: |
| if (Raw.NumOperands == 0) { |
| Res = new ReturnInst(); return false; |
| } else if (Raw.NumOperands == 1) { |
| Res = new ReturnInst(getValue(Raw.Ty, Raw.Arg1)); return false; |
| } |
| break; |
| |
| case Instruction::Br: |
| if (Raw.NumOperands == 1) { |
| Res = new BranchInst(cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg1))); |
| return false; |
| } else if (Raw.NumOperands == 3) { |
| Res = new BranchInst(cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg1)), |
| cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg2)), |
| getValue(Type::BoolTy , Raw.Arg3)); |
| return false; |
| } |
| break; |
| |
| case Instruction::Switch: { |
| SwitchInst *I = |
| new SwitchInst(getValue(Raw.Ty, Raw.Arg1), |
| cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg2))); |
| Res = I; |
| if (Raw.NumOperands < 3) return false; // No destinations? Wierd. |
| |
| if (Raw.NumOperands == 3 || Raw.VarArgs->size() & 1) { |
| cerr << "Switch statement with odd number of arguments!\n"; |
| delete I; |
| return failure(true); |
| } |
| |
| vector<unsigned> &args = *Raw.VarArgs; |
| for (unsigned i = 0; i < args.size(); i += 2) |
| I->dest_push_back(cast<ConstPoolVal>(getValue(Raw.Ty, args[i])), |
| cast<BasicBlock>(getValue(Type::LabelTy, args[i+1]))); |
| |
| delete Raw.VarArgs; |
| return false; |
| } |
| |
| case Instruction::Call: { |
| Method *M = cast<Method>(getValue(Raw.Ty, Raw.Arg1)); |
| if (M == 0) return failure(true); |
| |
| vector<Value *> Params; |
| const MethodType::ParamTypes &PL = M->getType()->getParamTypes(); |
| |
| if (!M->getType()->isVarArg()) { |
| MethodType::ParamTypes::const_iterator It = PL.begin(); |
| |
| switch (Raw.NumOperands) { |
| case 0: cerr << "Invalid call instruction encountered!\n"; |
| return failure(true); |
| case 1: break; |
| case 2: Params.push_back(getValue(*It++, Raw.Arg2)); break; |
| case 3: Params.push_back(getValue(*It++, Raw.Arg2)); |
| if (It == PL.end()) return failure(true); |
| Params.push_back(getValue(*It++, Raw.Arg3)); break; |
| default: |
| Params.push_back(getValue(*It++, Raw.Arg2)); |
| { |
| vector<unsigned> &args = *Raw.VarArgs; |
| for (unsigned i = 0; i < args.size(); i++) { |
| if (It == PL.end()) return failure(true); |
| // TODO: Check getValue for null! |
| Params.push_back(getValue(*It++, args[i])); |
| } |
| } |
| delete Raw.VarArgs; |
| } |
| if (It != PL.end()) return failure(true); |
| } else { |
| // The first parameter does not have a type specifier... because there |
| // must be at least one concrete argument to a vararg type... |
| Params.push_back(getValue(PL.front(), Raw.Arg2)); |
| |
| vector<unsigned> &args = *Raw.VarArgs; |
| if ((args.size() & 1) != 0) |
| return failure(true); // Must be pairs of type/value |
| for (unsigned i = 0; i < args.size(); i+=2) { |
| // TODO: Check getValue for null! |
| Params.push_back(getValue(getType(args[i]), args[i+1])); |
| } |
| delete Raw.VarArgs; |
| } |
| |
| Res = new CallInst(M, Params); |
| return false; |
| } |
| case Instruction::Malloc: |
| if (Raw.NumOperands > 2) return failure(true); |
| V = Raw.NumOperands ? getValue(Type::UIntTy, Raw.Arg1) : 0; |
| Res = new MallocInst(Raw.Ty, V); |
| return false; |
| |
| case Instruction::Alloca: |
| if (Raw.NumOperands > 2) return failure(true); |
| V = Raw.NumOperands ? getValue(Type::UIntTy, Raw.Arg1) : 0; |
| Res = new AllocaInst(Raw.Ty, V); |
| return false; |
| |
| case Instruction::Free: |
| V = getValue(Raw.Ty, Raw.Arg1); |
| if (!V->getType()->isPointerType()) return failure(true); |
| Res = new FreeInst(V); |
| return false; |
| |
| case Instruction::Load: |
| case Instruction::GetElementPtr: { |
| vector<ConstPoolVal*> Idx; |
| switch (Raw.NumOperands) { |
| case 0: cerr << "Invalid load encountered!\n"; return failure(true); |
| case 1: break; |
| case 2: V = getValue(Type::UByteTy, Raw.Arg2); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| break; |
| case 3: V = getValue(Type::UByteTy, Raw.Arg2); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| V = getValue(Type::UByteTy, Raw.Arg3); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| break; |
| default: |
| V = getValue(Type::UByteTy, Raw.Arg2); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| vector<unsigned> &args = *Raw.VarArgs; |
| for (unsigned i = 0, E = args.size(); i != E; ++i) { |
| V = getValue(Type::UByteTy, args[i]); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| } |
| delete Raw.VarArgs; |
| break; |
| } |
| if (Raw.Opcode == Instruction::Load) |
| Res = new LoadInst(getValue(Raw.Ty, Raw.Arg1), Idx); |
| else if (Raw.Opcode == Instruction::GetElementPtr) |
| Res = new GetElementPtrInst(getValue(Raw.Ty, Raw.Arg1), Idx); |
| else |
| abort(); |
| return false; |
| } |
| case Instruction::Store: { |
| vector<ConstPoolVal*> Idx; |
| switch (Raw.NumOperands) { |
| case 0: |
| case 1: cerr << "Invalid store encountered!\n"; return failure(true); |
| case 2: break; |
| case 3: V = getValue(Type::UByteTy, Raw.Arg3); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| break; |
| default: |
| vector<unsigned> &args = *Raw.VarArgs; |
| for (unsigned i = 0, E = args.size(); i != E; ++i) { |
| V = getValue(Type::UByteTy, args[i]); |
| if (!isa<ConstPoolVal>(V)) return failure(true); |
| Idx.push_back(cast<ConstPoolVal>(V)); |
| } |
| delete Raw.VarArgs; |
| break; |
| } |
| |
| const Type *ElType = StoreInst::getIndexedType(Raw.Ty, Idx); |
| if (ElType == 0) return failure(true); |
| Res = new StoreInst(getValue(ElType, Raw.Arg1), getValue(Raw.Ty, Raw.Arg2), |
| Idx); |
| return false; |
| } |
| } // end switch(Raw.Opcode) |
| |
| cerr << "Unrecognized instruction! " << Raw.Opcode |
| << " ADDR = 0x" << (void*)Buf << endl; |
| return failure(true); |
| } |