llvm-6502/lib/Bytecode/Reader/InstructionReader.cpp
Chris Lattner 05950c34a4 * Add real support for global variable addresses initializing constants
* Add minor optimization to BytecodeParser::refineAbstractType
* MethodType::get now take an explicit isVarArg parameter
* Fix encoding/decoding of VarArgs calls
* Support the Invoke instruction


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@760 91177308-0d34-0410-b5e6-96231b3b80d8
2001-10-13 06:47:01 +00:00

392 lines
13 KiB
C++

//===- 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: {
Value *M = getValue(Raw.Ty, Raw.Arg1);
if (M == 0) return failure(true);
// Check to make sure we have a pointer to method type
PointerType *PTy = dyn_cast<PointerType>(M->getType());
if (PTy == 0) return failure(true);
MethodType *MTy = dyn_cast<MethodType>(PTy->getValueType());
if (MTy == 0) return failure(true);
vector<Value *> Params;
const MethodType::ParamTypes &PL = MTy->getParamTypes();
if (!MTy->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 {
if (Raw.NumOperands > 2) {
vector<unsigned> &args = *Raw.VarArgs;
if (args.size() < 1) return failure(true);
if ((args.size() & 1) != 0)
return failure(true); // Must be pairs of type/value
for (unsigned i = 0; i < args.size(); i+=2) {
const Type *Ty = getType(args[i]);
if (Ty == 0)
return failure(true);
Value *V = getValue(Ty, args[i+1]);
if (V == 0) return failure(true);
Params.push_back(V);
}
delete Raw.VarArgs;
}
}
Res = new CallInst(M, Params);
return false;
}
case Instruction::Invoke: {
Value *M = getValue(Raw.Ty, Raw.Arg1);
if (M == 0) return failure(true);
// Check to make sure we have a pointer to method type
PointerType *PTy = dyn_cast<PointerType>(M->getType());
if (PTy == 0) return failure(true);
MethodType *MTy = dyn_cast<MethodType>(PTy->getValueType());
if (MTy == 0) return failure(true);
vector<Value *> Params;
const MethodType::ParamTypes &PL = MTy->getParamTypes();
vector<unsigned> &args = *Raw.VarArgs;
BasicBlock *Normal, *Except;
if (!MTy->isVarArg()) {
if (Raw.NumOperands < 3) return failure(true);
Normal = cast<BasicBlock>(getValue(Type::LabelTy, Raw.Arg2));
Except = cast<BasicBlock>(getValue(Type::LabelTy, args[0]));
MethodType::ParamTypes::const_iterator It = PL.begin();
for (unsigned i = 1; i < args.size(); i++) {
if (It == PL.end()) return failure(true);
// TODO: Check getValue for null!
Params.push_back(getValue(*It++, args[i]));
}
if (It != PL.end()) return failure(true);
} else {
if (args.size() < 4) return failure(true);
Normal = cast<BasicBlock>(getValue(Type::LabelTy, args[0]));
Except = cast<BasicBlock>(getValue(Type::LabelTy, args[2]));
if ((args.size() & 1) != 0)
return failure(true); // Must be pairs of type/value
for (unsigned i = 4; 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 InvokeInst(M, Normal, Except, 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);
}