1 //===- ReadInst.cpp - Code to read an instruction from bytecode -------------===
3 // This file defines the mechanism to read an instruction from a bytecode
6 // Note that this library should be as fast as possible, reentrant, and
9 // TODO: Change from getValue(Raw.Arg1) etc, to getArg(Raw, 1)
10 // Make it check type, so that casts are checked.
12 //===------------------------------------------------------------------------===
14 #include "llvm/iOther.h"
15 #include "llvm/iTerminators.h"
16 #include "llvm/iMemory.h"
17 #include "llvm/DerivedTypes.h"
18 #include "ReaderInternals.h"
20 bool BytecodeParser::ParseRawInst(const uchar *&Buf, const uchar *EndBuf,
23 if (read(Buf, EndBuf, Op)) return failure(true);
25 Result.NumOperands = Op >> 30;
26 Result.Opcode = (Op >> 24) & 63;
28 switch (Result.NumOperands) {
30 Result.Ty = getType((Op >> 12) & 4095);
31 Result.Arg1 = Op & 4095;
32 if (Result.Arg1 == 4095) // Handle special encoding for 0 operands...
33 Result.NumOperands = 0;
36 Result.Ty = getType((Op >> 16) & 255);
37 Result.Arg1 = (Op >> 8 ) & 255;
38 Result.Arg2 = (Op >> 0 ) & 255;
41 Result.Ty = getType((Op >> 18) & 63);
42 Result.Arg1 = (Op >> 12) & 63;
43 Result.Arg2 = (Op >> 6 ) & 63;
44 Result.Arg3 = (Op >> 0 ) & 63;
47 Buf -= 4; // Hrm, try this again...
48 if (read_vbr(Buf, EndBuf, Result.Opcode)) return failure(true);
49 if (read_vbr(Buf, EndBuf, Typ)) return failure(true);
50 Result.Ty = getType(Typ);
51 if (read_vbr(Buf, EndBuf, Result.NumOperands)) return failure(true);
53 switch (Result.NumOperands) {
55 cerr << "Zero Arg instr found!\n";
56 return failure(true); // This encoding is invalid!
58 if (read_vbr(Buf, EndBuf, Result.Arg1)) return failure(true);
61 if (read_vbr(Buf, EndBuf, Result.Arg1) ||
62 read_vbr(Buf, EndBuf, Result.Arg2)) return failure(true);
65 if (read_vbr(Buf, EndBuf, Result.Arg1) ||
66 read_vbr(Buf, EndBuf, Result.Arg2) ||
67 read_vbr(Buf, EndBuf, Result.Arg3)) return failure(true);
70 if (read_vbr(Buf, EndBuf, Result.Arg1) ||
71 read_vbr(Buf, EndBuf, Result.Arg2)) return failure(true);
73 // Allocate a vector to hold arguments 3, 4, 5, 6 ...
74 Result.VarArgs = new vector<unsigned>(Result.NumOperands-2);
75 for (unsigned a = 0; a < Result.NumOperands-2; a++)
76 if (read_vbr(Buf, EndBuf, (*Result.VarArgs)[a])) return failure(true);
79 if (align32(Buf, EndBuf)) return failure(true);
84 cerr << "NO: " << Result.NumOperands << " opcode: " << Result.Opcode
85 << " Ty: " << Result.Ty->getDescription() << " arg1: " << Result.Arg1
86 << " arg2: " << Result.Arg2 << " arg3: " << Result.Arg3 << endl;
92 bool BytecodeParser::ParseInstruction(const uchar *&Buf, const uchar *EndBuf,
95 if (ParseRawInst(Buf, EndBuf, Raw)) return failure(true);
97 if (Raw.Opcode >= Instruction::FirstUnaryOp &&
98 Raw.Opcode < Instruction::NumUnaryOps && Raw.NumOperands == 1) {
99 Res = UnaryOperator::create((Instruction::UnaryOps)Raw.Opcode,
100 getValue(Raw.Ty,Raw.Arg1));
102 } else if (Raw.Opcode >= Instruction::FirstBinaryOp &&
103 Raw.Opcode < Instruction::NumBinaryOps && Raw.NumOperands == 2) {
104 Res = BinaryOperator::create((Instruction::BinaryOps)Raw.Opcode,
105 getValue(Raw.Ty, Raw.Arg1),
106 getValue(Raw.Ty, Raw.Arg2));
111 switch (Raw.Opcode) {
112 case Instruction::Cast:
113 Res = new CastInst(getValue(Raw.Ty, Raw.Arg1), getType(Raw.Arg2));
116 case Instruction::PHINode: {
117 PHINode *PN = new PHINode(Raw.Ty);
118 switch (Raw.NumOperands) {
121 case 3: cerr << "Invalid phi node encountered!\n";
123 return failure(true);
124 case 2: PN->addIncoming(getValue(Raw.Ty, Raw.Arg1),
125 (BasicBlock*)getValue(Type::LabelTy, Raw.Arg2));
128 PN->addIncoming(getValue(Raw.Ty, Raw.Arg1),
129 (BasicBlock*)getValue(Type::LabelTy, Raw.Arg2));
130 if (Raw.VarArgs->size() & 1) {
131 cerr << "PHI Node with ODD number of arguments!\n";
133 return failure(true);
135 vector<unsigned> &args = *Raw.VarArgs;
136 for (unsigned i = 0; i < args.size(); i+=2)
137 PN->addIncoming(getValue(Raw.Ty, args[i]),
138 (BasicBlock*)getValue(Type::LabelTy, args[i+1]));
147 case Instruction::Shl:
148 case Instruction::Shr:
149 Res = new ShiftInst((Instruction::OtherOps)Raw.Opcode,
150 getValue(Raw.Ty, Raw.Arg1),
151 getValue(Type::UByteTy, Raw.Arg2));
153 case Instruction::Ret:
154 if (Raw.NumOperands == 0) {
155 Res = new ReturnInst(); return false;
156 } else if (Raw.NumOperands == 1) {
157 Res = new ReturnInst(getValue(Raw.Ty, Raw.Arg1)); return false;
161 case Instruction::Br:
162 if (Raw.NumOperands == 1) {
163 Res = new BranchInst((BasicBlock*)getValue(Type::LabelTy, Raw.Arg1));
165 } else if (Raw.NumOperands == 3) {
166 Res = new BranchInst((BasicBlock*)getValue(Type::LabelTy, Raw.Arg1),
167 (BasicBlock*)getValue(Type::LabelTy, Raw.Arg2),
168 getValue(Type::BoolTy , Raw.Arg3));
173 case Instruction::Switch: {
175 new SwitchInst(getValue(Raw.Ty, Raw.Arg1),
176 (BasicBlock*)getValue(Type::LabelTy, Raw.Arg2));
178 if (Raw.NumOperands < 3) return false; // No destinations? Wierd.
180 if (Raw.NumOperands == 3 || Raw.VarArgs->size() & 1) {
181 cerr << "Switch statement with odd number of arguments!\n";
183 return failure(true);
186 vector<unsigned> &args = *Raw.VarArgs;
187 for (unsigned i = 0; i < args.size(); i += 2)
188 I->dest_push_back((ConstPoolVal*)getValue(Raw.Ty, args[i]),
189 (BasicBlock*)getValue(Type::LabelTy, args[i+1]));
195 case Instruction::Call: {
196 Method *M = (Method*)getValue(Raw.Ty, Raw.Arg1);
197 if (M == 0) return failure(true);
199 vector<Value *> Params;
200 const MethodType::ParamTypes &PL = M->getMethodType()->getParamTypes();
202 if (!M->getType()->isMethodType()->isVarArg()) {
203 MethodType::ParamTypes::const_iterator It = PL.begin();
205 switch (Raw.NumOperands) {
206 case 0: cerr << "Invalid call instruction encountered!\n";
207 return failure(true);
209 case 2: Params.push_back(getValue(*It++, Raw.Arg2)); break;
210 case 3: Params.push_back(getValue(*It++, Raw.Arg2));
211 if (It == PL.end()) return failure(true);
212 Params.push_back(getValue(*It++, Raw.Arg3)); break;
214 Params.push_back(getValue(*It++, Raw.Arg2));
216 vector<unsigned> &args = *Raw.VarArgs;
217 for (unsigned i = 0; i < args.size(); i++) {
218 if (It == PL.end()) return failure(true);
219 // TODO: Check getValue for null!
220 Params.push_back(getValue(*It++, args[i]));
225 if (It != PL.end()) return failure(true);
227 // The first parameter does not have a type specifier... because there
228 // must be at least one concrete argument to a vararg type...
229 Params.push_back(getValue(PL.front(), Raw.Arg2));
231 vector<unsigned> &args = *Raw.VarArgs;
232 if ((args.size() & 1) != 0)
233 return failure(true); // Must be pairs of type/value
234 for (unsigned i = 0; i < args.size(); i+=2) {
235 // TODO: Check getValue for null!
236 Params.push_back(getValue(getType(args[i]), args[i+1]));
241 Res = new CallInst(M, Params);
244 case Instruction::Malloc:
245 if (Raw.NumOperands > 2) return failure(true);
246 V = Raw.NumOperands ? getValue(Type::UIntTy, Raw.Arg1) : 0;
247 Res = new MallocInst(Raw.Ty, V);
250 case Instruction::Alloca:
251 if (Raw.NumOperands > 2) return failure(true);
252 V = Raw.NumOperands ? getValue(Type::UIntTy, Raw.Arg1) : 0;
253 Res = new AllocaInst(Raw.Ty, V);
256 case Instruction::Free:
257 V = getValue(Raw.Ty, Raw.Arg1);
258 if (!V->getType()->isPointerType()) return failure(true);
259 Res = new FreeInst(V);
262 case Instruction::Load:
263 case Instruction::GetElementPtr: {
264 vector<ConstPoolVal*> Idx;
265 switch (Raw.NumOperands) {
266 case 0: cerr << "Invalid load encountered!\n"; return failure(true);
268 case 2: V = getValue(Type::UByteTy, Raw.Arg2);
269 if (!V->isConstant()) return failure(true);
270 Idx.push_back(V->castConstant());
272 case 3: V = getValue(Type::UByteTy, Raw.Arg2);
273 if (!V->isConstant()) return failure(true);
274 Idx.push_back(V->castConstant());
275 V = getValue(Type::UByteTy, Raw.Arg3);
276 if (!V->isConstant()) return failure(true);
277 Idx.push_back(V->castConstant());
280 V = getValue(Type::UByteTy, Raw.Arg2);
281 if (!V->isConstant()) return failure(true);
282 Idx.push_back(V->castConstant());
283 vector<unsigned> &args = *Raw.VarArgs;
284 for (unsigned i = 0, E = args.size(); i != E; ++i) {
285 V = getValue(Type::UByteTy, args[i]);
286 if (!V->isConstant()) return failure(true);
287 Idx.push_back(V->castConstant());
292 if (Raw.Opcode == Instruction::Load)
293 Res = new LoadInst(getValue(Raw.Ty, Raw.Arg1), Idx);
294 else if (Raw.Opcode == Instruction::GetElementPtr)
295 Res = new GetElementPtrInst(getValue(Raw.Ty, Raw.Arg1), Idx);
300 case Instruction::Store: {
301 vector<ConstPoolVal*> Idx;
302 switch (Raw.NumOperands) {
304 case 1: cerr << "Invalid store encountered!\n"; return failure(true);
306 case 3: V = getValue(Type::UByteTy, Raw.Arg3);
307 if (!V->isConstant()) return failure(true);
308 Idx.push_back(V->castConstant());
311 vector<unsigned> &args = *Raw.VarArgs;
312 for (unsigned i = 0, E = args.size(); i != E; ++i) {
313 V = getValue(Type::UByteTy, args[i]);
314 if (!V->isConstant()) return failure(true);
315 Idx.push_back(V->castConstant());
321 const Type *ElType = StoreInst::getIndexedType(Raw.Ty, Idx);
322 if (ElType == 0) return failure(true);
323 Res = new StoreInst(getValue(ElType, Raw.Arg1), getValue(Raw.Ty, Raw.Arg2),
327 } // end switch(Raw.Opcode)
329 cerr << "Unrecognized instruction! " << Raw.Opcode
330 << " ADDR = 0x" << (void*)Buf << endl;
331 return failure(true);