ExpOperation* ExpEvaluator::popOne(ObjList& stack)
{
ExpOperation* o = 0;
for (;;) {
o = static_cast<ExpOperation*>(stack.get());
if (o || !stack.next())
break;
// non-terminal NULL - remove the list entry
stack.remove();
}
if (o && o->barrier()) {
XDebug(DebugInfo,"Not popping barrier %u: '%s'='%s'",o->opcode(),o->name().c_str(),o->c_str());
return 0;
}
stack.remove(o,false);
#ifdef DEBUG
#ifdef XDEBUG
Debug(DebugAll,"popOne: %p%s%s",o,
(YOBJECT(ExpFunction,o) ? " function" : ""),
(YOBJECT(ExpWrapper,o) ? " wrapper" : ""));
#else
Debug(DebugAll,"popOne: %p",o);
#endif
#endif
return o;
}
bool ExpEvaluator::runOperation(ObjList& stack, const ExpOperation& oper, GenObject* context) const
{
DDebug(this,DebugAll,"runOperation(%p,%u,%p) %s",&stack,oper.opcode(),context,getOperator(oper.opcode()));
XDebug(this,DebugAll,"stack: %s",dump(stack).c_str());
bool boolRes = true;
switch (oper.opcode()) {
case OpcPush:
case OpcField:
pushOne(stack,oper.clone());
break;
case OpcCopy:
{
Mutex* mtx = 0;
ScriptRun* runner = YOBJECT(ScriptRun,&oper);
if (runner) {
if (runner->context())
mtx = runner->context()->mutex();
if (!mtx)
mtx = runner;
}
pushOne(stack,oper.copy(mtx));
}
break;
case OpcNone:
case OpcLabel:
break;
case OpcDrop:
TelEngine::destruct(popOne(stack));
break;
case OpcDup:
{
ExpOperation* op = popValue(stack,context);
if (!op)
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
pushOne(stack,op->clone());
pushOne(stack,op);
}
break;
case OpcAnd:
case OpcOr:
case OpcXor:
case OpcShl:
case OpcShr:
case OpcAdd:
case OpcSub:
case OpcMul:
case OpcDiv:
case OpcMod:
boolRes = false;
// fall through
case OpcEq:
case OpcNe:
case OpcLt:
case OpcGt:
case OpcLe:
case OpcGe:
{
ExpOperation* op2 = popValue(stack,context);
ExpOperation* op1 = popValue(stack,context);
if (!op1 || !op2) {
TelEngine::destruct(op1);
TelEngine::destruct(op2);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
switch (oper.opcode()) {
case OpcDiv:
case OpcMod:
if (!op2->valInteger())
return gotError("Division by zero",oper.lineNumber());
case OpcAdd:
if (op1->isInteger() && op2->isInteger())
break;
// turn addition into concatenation
{
String val = *op1 + *op2;
TelEngine::destruct(op1);
TelEngine::destruct(op2);
DDebug(this,DebugAll,"String result: '%s'",val.c_str());
pushOne(stack,new ExpOperation(val));
return true;
}
default:
break;
}
long int val = 0;
switch (oper.opcode()) {
case OpcAnd:
val = op1->valInteger() & op2->valInteger();
break;
case OpcOr:
val = op1->valInteger() | op2->valInteger();
break;
case OpcXor:
val = op1->valInteger() ^ op2->valInteger();
break;
case OpcShl:
val = op1->valInteger() << op2->valInteger();
break;
case OpcShr:
val = op1->valInteger() >> op2->valInteger();
break;
case OpcAdd:
val = op1->valInteger() + op2->valInteger();
break;
case OpcSub:
val = op1->valInteger() - op2->valInteger();
break;
case OpcMul:
val = op1->valInteger() * op2->valInteger();
break;
case OpcDiv:
val = op1->valInteger() / op2->valInteger();
break;
case OpcMod:
val = op1->valInteger() % op2->valInteger();
break;
case OpcLt:
val = (op1->valInteger() < op2->valInteger()) ? 1 : 0;
break;
case OpcGt:
val = (op1->valInteger() > op2->valInteger()) ? 1 : 0;
break;
case OpcLe:
val = (op1->valInteger() <= op2->valInteger()) ? 1 : 0;
break;
case OpcGe:
val = (op1->valInteger() >= op2->valInteger()) ? 1 : 0;
break;
case OpcEq:
val = (*op1 == *op2) ? 1 : 0;
break;
case OpcNe:
val = (*op1 != *op2) ? 1 : 0;
break;
default:
break;
}
TelEngine::destruct(op1);
TelEngine::destruct(op2);
if (boolRes) {
DDebug(this,DebugAll,"Bool result: '%s'",String::boolText(val != 0));
pushOne(stack,new ExpOperation(val != 0));
}
else {
DDebug(this,DebugAll,"Numeric result: %lu",val);
pushOne(stack,new ExpOperation(val));
}
}
break;
case OpcLAnd:
case OpcLOr:
{
ExpOperation* op2 = popValue(stack,context);
ExpOperation* op1 = popValue(stack,context);
if (!op1 || !op2) {
TelEngine::destruct(op1);
TelEngine::destruct(op2);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
bool val = false;
switch (oper.opcode()) {
case OpcLAnd:
val = op1->valBoolean() && op2->valBoolean();
break;
case OpcLOr:
val = op1->valBoolean() || op2->valBoolean();
break;
default:
break;
}
TelEngine::destruct(op1);
TelEngine::destruct(op2);
DDebug(this,DebugAll,"Bool result: '%s'",String::boolText(val));
pushOne(stack,new ExpOperation(val));
}
break;
case OpcCat:
{
ExpOperation* op2 = popValue(stack,context);
ExpOperation* op1 = popValue(stack,context);
if (!op1 || !op2) {
TelEngine::destruct(op1);
TelEngine::destruct(op2);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
String val = *op1 + *op2;
TelEngine::destruct(op1);
TelEngine::destruct(op2);
DDebug(this,DebugAll,"String result: '%s'",val.c_str());
pushOne(stack,new ExpOperation(val));
}
break;
case OpcAs:
{
ExpOperation* op2 = popOne(stack);
ExpOperation* op1 = popOne(stack);
if (!op1 || !op2) {
TelEngine::destruct(op1);
TelEngine::destruct(op2);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
pushOne(stack,op1->clone(*op2));
TelEngine::destruct(op1);
TelEngine::destruct(op2);
}
break;
case OpcNeg:
case OpcNot:
case OpcLNot:
{
ExpOperation* op = popValue(stack,context);
if (!op)
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
switch (oper.opcode()) {
case OpcNeg:
pushOne(stack,new ExpOperation(-op->valInteger()));
break;
case OpcNot:
pushOne(stack,new ExpOperation(~op->valInteger()));
break;
case OpcLNot:
pushOne(stack,new ExpOperation(!op->valBoolean()));
break;
default:
pushOne(stack,new ExpOperation(op->valInteger()));
break;
}
TelEngine::destruct(op);
}
break;
case OpcFunc:
return runFunction(stack,oper,context) ||
gotError("Function '" + oper.name() + "' call failed",oper.lineNumber());
case OpcIncPre:
case OpcDecPre:
case OpcIncPost:
case OpcDecPost:
{
ExpOperation* fld = popOne(stack);
if (!fld)
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
if (fld->opcode() != OpcField) {
TelEngine::destruct(fld);
return gotError("Expecting LValue in operator",oper.lineNumber());
}
ExpOperation* val = 0;
if (!(runField(stack,*fld,context) && (val = popOne(stack)))) {
TelEngine::destruct(fld);
return false;
}
long int num = val->valInteger();
switch (oper.opcode()) {
case OpcIncPre:
num++;
(*val) = num;
break;
case OpcDecPre:
num--;
(*val) = num;
break;
case OpcIncPost:
(*val) = num;
num++;
break;
case OpcDecPost:
(*val) = num;
num--;
break;
default:
break;
}
(*fld) = num;
bool ok = runAssign(stack,*fld,context);
TelEngine::destruct(fld);
if (!ok) {
TelEngine::destruct(val);
return gotError("Assignment failed",oper.lineNumber());
}
pushOne(stack,val);
}
break;
case OpcAssign:
{
ExpOperation* val = popValue(stack,context);
ExpOperation* fld = popOne(stack);
if (!fld || !val) {
TelEngine::destruct(fld);
TelEngine::destruct(val);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
if (fld->opcode() != OpcField) {
TelEngine::destruct(fld);
TelEngine::destruct(val);
return gotError("Expecting LValue in assignment",oper.lineNumber());
}
ExpOperation* op = val->clone(fld->name());
TelEngine::destruct(fld);
bool ok = runAssign(stack,*op,context);
TelEngine::destruct(op);
if (!ok) {
TelEngine::destruct(val);
return gotError("Assignment failed",oper.lineNumber());
}
pushOne(stack,val);
}
break;
default:
if (oper.opcode() & OpcAssign) {
// assignment by operation
ExpOperation* val = popValue(stack,context);
ExpOperation* fld = popOne(stack);
if (!fld || !val) {
TelEngine::destruct(fld);
TelEngine::destruct(val);
return gotError("ExpEvaluator stack underflow",oper.lineNumber());
}
if (fld->opcode() != OpcField) {
TelEngine::destruct(fld);
TelEngine::destruct(val);
return gotError("Expecting LValue in assignment",oper.lineNumber());
}
pushOne(stack,fld->clone());
pushOne(stack,fld);
pushOne(stack,val);
ExpOperation op((Opcode)(oper.opcode() & ~OpcAssign),
oper.name(),oper.number(),oper.barrier());
if (!runOperation(stack,op,context))
return false;
static const ExpOperation assign(OpcAssign);
return runOperation(stack,assign,context);
}
Debug(this,DebugStub,"Please implement operation %u '%s'",
oper.opcode(),getOperator(oper.opcode()));
return false;
}
return true;
}
bool ExpEvaluator::trySimplify()
{
DDebug(this,DebugInfo,"trySimplify");
bool done = false;
for (unsigned int i = 0; ; i++) {
ExpOperation* o = static_cast<ExpOperation*>(m_opcodes[i]);
if (!o) {
if (i >= m_opcodes.length())
break;
else
continue;
}
if (o->barrier())
continue;
switch (o->opcode()) {
case OpcLAnd:
case OpcLOr:
case OpcLXor:
case OpcAnd:
case OpcOr:
case OpcXor:
case OpcShl:
case OpcShr:
case OpcAdd:
case OpcSub:
case OpcMul:
case OpcDiv:
case OpcMod:
case OpcCat:
case OpcEq:
case OpcNe:
case OpcLt:
case OpcGt:
case OpcLe:
case OpcGe:
if (i >= 2) {
ExpOperation* op2 = static_cast<ExpOperation*>(m_opcodes[i-1]);
ExpOperation* op1 = static_cast<ExpOperation*>(m_opcodes[i-2]);
if (!op1 || !op2)
continue;
if (o->opcode() == OpcLAnd || o->opcode() == OpcAnd || o->opcode() == OpcMul) {
if ((op1->opcode() == OpcPush && !op1->number() && op2->opcode() == OpcField) ||
(op2->opcode() == OpcPush && !op2->number() && op1->opcode() == OpcField)) {
ExpOperation* newOp = (o->opcode() == OpcLAnd) ? new ExpOperation(false) : new ExpOperation((long int)0);
newOp->lineNumber(o->lineNumber());
(m_opcodes+i)->set(newOp);
m_opcodes.remove(op1);
m_opcodes.remove(op2);
i -= 2;
done = true;
continue;
}
}
if (o->opcode() == OpcLOr) {
if ((op1->opcode() == OpcPush && op1->number() && op2->opcode() == OpcField) ||
(op2->opcode() == OpcPush && op2->number() && op1->opcode() == OpcField)) {
ExpOperation* newOp = new ExpOperation(true);
newOp->lineNumber(o->lineNumber());
(m_opcodes+i)->set(newOp);
m_opcodes.remove(op1);
m_opcodes.remove(op2);
i -= 2;
done = true;
continue;
}
}
if ((op1->opcode() == OpcPush) && (op2->opcode() == OpcPush)) {
ObjList stack;
pushOne(stack,op1->clone());
pushOne(stack,op2->clone());
if (runOperation(stack,*o)) {
// replace operators and operation with computed constant
ExpOperation* newOp = popOne(stack);
newOp->lineNumber(o->lineNumber());
(m_opcodes+i)->set(newOp);
m_opcodes.remove(op1);
m_opcodes.remove(op2);
i -= 2;
done = true;
}
}
}
break;
case OpcNeg:
case OpcNot:
case OpcLNot:
if (i >= 1) {
ExpOperation* op = static_cast<ExpOperation*>(m_opcodes[i-1]);
if (!op)
continue;
if (op->opcode() == OpcPush) {
ObjList stack;
pushOne(stack,op->clone());
if (runOperation(stack,*o)) {
// replace unary operator and operation with computed constant
ExpOperation* newOp = popOne(stack);
newOp->lineNumber(o->lineNumber());
(m_opcodes+i)->set(newOp);
m_opcodes.remove(op);
i--;
done = true;
}
}
else if (op->opcode() == o->opcode() && op->opcode() != OpcLNot) {
// minus or bit negation applied twice - remove both operators
m_opcodes.remove(o);
m_opcodes.remove(op);
i--;
done = true;
}
}
break;
default:
break;
}
}
return done;
}