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Parser.cpp
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Parser.cpp
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#include <iostream>
#include <string>
#include <sstream>
#include <cstring>
#include <cstdlib>
#include "Parser.h"
#include "Scanner.h"
#include "Token.h"
using namespace std;
Parser::Parser(Scanner* s, const char* genfile)
:mScanner(s)
,mTok(Token())
,mPreScanned(false)
,mErrorCount(0)
,mError(false)
,mLevel(-1)
,mFunctionCallCounter(0)
,mCurrentAddr(0)
,mReg(0)
,mArrayID(NULL)
,mGenFile(genfile)
,mLocalSymbols(0)
,mFunctionNames(0)
,mHaveReturn(0)
{}
Parser::~Parser()
{}
void Parser::initialize()
{
vector<SymbolType> params;
params.resize(0);
mGlobalSymbols["getBool"] = Symbol("getBool",
SymbolType(FUNCTION, BOOLEAN),
mCurrentAddr++);
mGenFile << "getBool:" << endl
<< "\tR[0] = (int)getBool();" << endl;
calleeEnd(false);
mGlobalSymbols["getInt"] = Symbol("getInt",
SymbolType(FUNCTION, INTEGER),
mCurrentAddr++);
mGenFile << "getInt:" << endl
<< "\tR[0] = getInt();" << endl;
calleeEnd(false);
mGlobalSymbols["getString"] = Symbol("getString",
SymbolType(FUNCTION, STRING),
mCurrentAddr++);
mGenFile << "getString:" << endl
<< "\tgetString(TMP_STRING);" << endl
<< "\tR[0] = (int)TMP_STRING;" << endl;
calleeEnd(false);
mGlobalSymbols["getFloat"] = Symbol("getFloat",
SymbolType(FUNCTION, FLOAT),
mCurrentAddr++);
mGenFile << "getFloat:" << endl
<< "\tTMP_FLOAT1 = getFloat();" << endl
<< "\tmemcpy(&R[0], &TMP_FLOAT1, sizeof(float));" << endl;
calleeEnd(false);
params.resize(1);
params[0] = SymbolType(SCALAR, BOOLEAN);
mGlobalSymbols["putBool"] = Symbol("putBool",
SymbolType(FUNCTION, INTEGER, 0, params),
mCurrentAddr++);
mReg = 1;
mGenFile << "putBool:" << endl
<< "\tR[0] = MM[R[SP] - 1];" << endl
<< "\tR[1] = putBool((bool)R[0]);" << endl;
calleeEnd(false);
params[0].setDataType(INTEGER);
mGlobalSymbols["putInt"] = Symbol("putInt",
SymbolType(FUNCTION, INTEGER, 0, params),
mCurrentAddr++);
mReg = 1;
mGenFile << "putInt:" << endl
<< "\tR[0] = MM[R[SP] - 1];" << endl
<< "\tR[1] = putInt(R[0]);" << endl;
calleeEnd(false);
mGlobalSymbols["sqrt"] = Symbol("sqrt",
SymbolType(FUNCTION, FLOAT, 0, params),
mCurrentAddr++);
mReg = 1;
mGenFile << "sqrt:" << endl
<< "\tR[0] = MM[R[SP] - 1];" << endl
<< "\tTMP_FLOAT1 = sqrt(R[0]);" << endl
<< "\tmemcpy(&R[1], &TMP_FLOAT1, sizeof(float));" << endl;
calleeEnd(false);
params[0].setDataType(STRING);
mGlobalSymbols["putString"] = Symbol("putString",
SymbolType(FUNCTION, INTEGER, 0, params),
mCurrentAddr++);
mReg = 1;
mGenFile << "putString:" << endl
<< "\tR[0] = MM[R[SP] - 1];" << endl
<< "\tR[1] = putString((char*)R[0]);" << endl;
calleeEnd(false);
params[0].setDataType(FLOAT);
mGlobalSymbols["putFloat"] = Symbol("putFloat",
SymbolType(FUNCTION, INTEGER, 0, params),
mCurrentAddr++);
mReg = 1;
mGenFile << "putFloat:" << endl
<< "\tR[0] = MM[R[SP] - 1];" << endl
<< "\tmemcpy(&TMP_FLOAT1, &R[0], sizeof(float));" << endl
<< "\tR[1] = putFloat(TMP_FLOAT1);" << endl;
calleeEnd(false);
}
Token Parser::nextToken()
{
if(mPreScanned)
mPreScanned = false;
else
mScanner->scan(mTok);
return mTok;
}
bool Parser::nextTokenIs(Token::tokentype tt)
{
if(nextToken().getType() == tt)
return true;
mPreScanned = true;
return false;
}
bool Parser::lookupSymbol(string id, SymbolTableIt& it, bool& global)
{
global = true;
it = localSymbolTable().find(id);
if(it == localSymbolTable().end())
it = mGlobalSymbols.find(id);
else
{
global = false;
return true;
}
return (it != mGlobalSymbols.end());
}
void Parser::getMemoryLocation(int fpOffset, bool global/*= false*/)
{
mReg++;
mGenFile << "\tR[" << mReg << "] = " << fpOffset << ";" << endl;
if(!global)
mGenFile << "\tR[" << mReg << "] = R[" << mReg << "] + R[FP];" << endl;
}
void Parser::doOperation(int op1, int op2, const char* op,
bool fp1,/*= false*/ bool fp2/*= false*/)
{
mReg++;
if(fp1 || fp2)
{
if(fp1)
mGenFile << "\tmemcpy(&TMP_FLOAT1, &R[" << op1 << "], sizeof(float));"
<< endl;
else
mGenFile << "\tTMP_FLOAT1 = R[" << op1 << "];" << endl;
if(fp2)
mGenFile << "\tmemcpy(&TMP_FLOAT2, &R[" << op2 << "], sizeof(float));"
<< endl;
else
mGenFile << "\tTMP_FLOAT2 = R[" << op2 << "];" << endl;
mGenFile << "\tTMP_FLOAT1 = TMP_FLOAT1 " << op << " TMP_FLOAT2;" << endl
<< "\tmemcpy(&R[" << mReg << "], &TMP_FLOAT1, sizeof(float));"
<< endl;
}
else
mGenFile << "\tR[" << mReg << "] = R[" << op1 << "] " << op
<< " R[" << op2 << "];" << endl;
}
void Parser::throwError(string err)
{
std::cout << "error on line " << mScanner->getLineNumber() << ": "
<< err << std::endl;
mError = true;
mErrorCount++;
}
void Parser::throwWarning(string warn)
{
std::cout << "warning: " << mScanner->getLineNumber() << ": "
<< warn << std::endl;
}
void Parser::callerBegin(std::vector<int>& regs, const char* id)
{
// push arguments on to stack, in reverse order
vector<int>::reverse_iterator rit;
for(rit = regs.rbegin(); rit != regs.rend(); ++rit)
mGenFile << "\tR[SP] = R[SP] + 1;" << endl
<< "\tMM[R[SP]] = R[" << *rit << "];" << endl;
int addr = mReg++;
mGenFile << "\tR[" << mReg << "] = (int)&&" << id
<< mFunctionCallCounter << ";" << endl
<< "\tR[SP] = R[SP] + 1;" << endl
<< "\tMM[R[SP]] = R[" << mReg << "];" << endl
<< "\tgoto *(void*)R[" << addr << "];" << endl;
}
void Parser::callerEnd(std::vector<int>& regs, const char* id)
{
mReg = 0;
mGenFile << id << mFunctionCallCounter << ":" << endl
<< "\tR[" << mReg << "] = MM[R[SP]];" << endl
<< "\tR[SP] = R[SP] - 1;" << endl;
mFunctionCallCounter++;
// pop arguments off stack
if(regs.size() > 0)
mGenFile << "\tR[SP] = R[SP] - " << regs.size() << ";" << endl;
}
void Parser::calleeBegin()
{
mGenFile << "\tR[SP] = R[SP] + 1;" << endl
<< "\tMM[R[SP]] = R[FP];" << endl
<< "\tR[FP] = R[SP] - 1;" << endl;
}
void Parser::calleeEnd(bool restorePointers/*=true*/)
{
int ret = mReg;
mReg++;
if(restorePointers)
mGenFile << "\tR[FP] = MM[R[SP]];" << endl
<< "\tR[SP] = R[SP] - 1;" << endl;
mGenFile << "\tR[" << mReg << "] = MM[R[SP]];" << endl
<< "\tMM[R[SP]] = R[" << ret << "];" << endl
<< "\tgoto *(void*)R[" << mReg << "];" << endl;
mReg = 0;
}
bool Parser::typemark(datatype& dt)
{
if(nextTokenIs(Token::INTEGER))
dt = INTEGER;
else if(nextTokenIs(Token::FLOAT))
dt = FLOAT;
else if(nextTokenIs(Token::BOOLEAN))
dt = BOOLEAN;
else if(nextTokenIs(Token::STRING))
dt = STRING;
else
return false;
return true;
}
bool Parser::variabledecl(int addr, datatype dt, SymbolType& st,
bool global/*= false*/)
{
SymbolTable& table = global ? mGlobalSymbols : localSymbolTable();
int tmpAddr = global ? mCurrentAddr++ : addr;
if(nextTokenIs(Token::IDENTIFIER))
{
const char* id = mTok.getString();
if(nextTokenIs(Token::OPENSQUARE) && nextTokenIs(Token::NUMBER))
{
if(getNumberType() != INTEGER)
{
throwError("array index must be an integer");
return false;
}
int size = atoi(mTok.getString());
if(nextTokenIs(Token::CLOSESQUARE))
{
st = SymbolType(ARRAY, dt, size);
table[id] = Symbol(id, st, tmpAddr);
return true;
}
stringstream m;
m << "expected ], not " << mTok.getString();
throwError(m.str());
return false;
}
st = SymbolType(SCALAR, dt);
table[id] = Symbol(id, st, tmpAddr);
return true;
}
return false;
}
bool Parser::declaration(int addr, SymbolType& st, bool& global)
{
if(nextTokenIs(Token::GLOBAL))
{
if(mLevel == 0)
global = true;
else
throwWarning("global specifier only valid at top level. ignoring.");
}
datatype dt;
if(typemark(dt))
return functiondecl(addr, dt, global) || variabledecl(addr, dt, st, global);
return false;
}
bool Parser::ifstatement()
{
datatype dt;
if(nextTokenIs(Token::IF) && expression(dt))
{
if(dt != BOOLEAN && dt != INTEGER)
{
throwError("conditional expressions must be convertable to boolean");
return false;
}
int labelnum = mFunctionCallCounter++;
mGenFile << "\tif(!R[" << mReg << "]) goto else"
<< labelnum << ";" << endl;
if(nextTokenIs(Token::THEN) &&
statement() &&
nextTokenIs(Token::SEMICOLON))
{
while(statement())
{
if(!nextTokenIs(Token::SEMICOLON))
{
throwError("expected ;");
return false;
}
}
mGenFile << "\tgoto endif" << labelnum << ";" << endl;
if(nextTokenIs(Token::ELSE))
{
mGenFile << "else" << labelnum << ":" << endl;
if(statement() && nextTokenIs(Token::SEMICOLON))
{
while(statement())
{
if(!nextTokenIs(Token::SEMICOLON))
{
throwError("expected ;");
return false;
}
}
}
}
else
mGenFile << "else" << labelnum << ":" << endl;
mGenFile << "endif" << labelnum << ":" << endl;
return nextTokenIs(Token::END) && nextTokenIs(Token::IF);
}
}
return false;
}
bool Parser::loopstatement()
{
datatype dt;
if(nextTokenIs(Token::FOR) && assignmentstatement())
{
int labelnum = mFunctionCallCounter++;
mGenFile << "beginfor" << labelnum << ":" << endl;
if(expression(dt))
{
mGenFile << "\tif(!R[" << mReg << "]) goto endfor"
<< labelnum << ";" << endl;
if(dt != BOOLEAN && dt != INTEGER)
{
throwError("conditional expressions must be convertable to boolean");
return false;
}
while(statement())
{
if(!nextTokenIs(Token::SEMICOLON))
{
throwError("expected ;");
return false;
}
}
if(nextTokenIs(Token::END) && nextTokenIs(Token::FOR))
{
mGenFile << "\tgoto beginfor" << labelnum << ";" << endl
<< "endfor" << labelnum << ":" << endl;
return true;
}
}
}
return false;
}
bool Parser::functioncall(vector<int>& regs)
{
const char* id = mTok.getString();
vector<SymbolType> args;
if(nextTokenIs(Token::OPENPAREN))
{
SymbolTableIt it;
bool global;
if(!lookupSymbol(id, it, global) ||
it->second.getStructureType() != FUNCTION)
{
mPreScanned = true;
return false;
}
argumentlist(args, regs);
if(nextTokenIs(Token::CLOSEPAREN))
{
vector<SymbolType> params;
it->second.getSymbolType().getParams(params);
if(params != args)
{
std::stringstream m;
m << "argument types do match function signature for " << id;
throwError(m.str());
return false;
}
return true;
}
}
return false;
}
bool Parser::argumentlist(vector<SymbolType>& args, vector<int>& regs)
{
datatype dt;
mArrayID = NULL;
if(expression(dt))
{
if(mArrayID)
{
SymbolTableIt it;
bool global;
lookupSymbol(mArrayID, it, global);
SymbolType st = it->second.getSymbolType();
args.push_back(st);
int size = st.getSize();
// mReg - 1 has address of first element, from factor()
int addr = mReg - 1;
regs.push_back(mReg);
for(int i = 1; i < size; i++)
{
mReg++;
mGenFile << "\tR[" << addr << "] = R[" << addr << "] + 1;" << endl
<< "\tR[" << mReg << "] = MM[R[" << addr << "]];" << endl;
regs.push_back(mReg);
}
}
else
{
args.push_back(SymbolType(SCALAR, dt));
regs.push_back(mReg);
}
if(nextTokenIs(Token::COMMA) && !argumentlist(args, regs))
{
throwError("syntax error in argument list");
return false;
}
return true;
}
return false;
}
bool Parser::name(bool& hasIndex)
{
datatype dt;
if(nextTokenIs(Token::OPENSQUARE) &&
expression(dt))
{
if(dt != BOOLEAN && dt != INTEGER)
{
throwError("array indexes must be integers");
return false;
}
hasIndex = true;
if(nextTokenIs(Token::CLOSESQUARE))
return true;
}
// already checked identifier
return true;
}
bool Parser::factor(datatype& dt)
{
if(nextTokenIs(Token::OPENPAREN))
{
if(expression(dt) && nextTokenIs(Token::CLOSEPAREN))
return true;
throwError("unmatched parentheses in expression");
return false;
}
bool negate = nextTokenIs(Token::MINUS);
if(nextTokenIs(Token::IDENTIFIER))
{
const char* id = mTok.getString();
bool hasIndex = false;
vector<int> regs;
bool isFunctionCall = functioncall(regs);
if(isFunctionCall || name(hasIndex))
{
int idx = mReg;
SymbolTableIt it;
bool global = false;
if(!lookupSymbol(id, it, global))
{
stringstream m;
m << "symbol \"" << id << "\" not found";
throwError(m.str());
return false;
}
int addr = it->second.getAddr();
dt = it->second.getDataType();
getMemoryLocation(addr, global);
// if we were given an index, we need to add the offset
if(hasIndex)
mGenFile << "\tR[" << mReg << "] = R[" << mReg << "] "
<< (addr < 0 ? '-' : '+') << " R[" << idx << "];" << endl;
mReg++;
mGenFile << "\tR[" << mReg << "] = MM[R[" << mReg - 1 << "]];" << endl;
if(negate)
{
mReg++;
mGenFile << "\tR[" << mReg << "] = -1*R[" << mReg - 1 << "];" << endl;
}
if(isFunctionCall)
{
callerBegin(regs, id);
callerEnd(regs, id);
}
// hack to allow arrays as expression
if(it->second.getStructureType() == ARRAY && !hasIndex)
mArrayID = const_cast<char*>(id);
}
}
else if(nextTokenIs(Token::NUMBER))
{
dt = getNumberType();
if(dt == INTEGER)
mGenFile << "\tR[" << ++mReg << "] = ";
else
mGenFile << "\tTMP_FLOAT1 = ";
mGenFile << (negate ? "-" : "") << mTok.getString() << ";" << endl;
if(dt == FLOAT)
mGenFile << "\tmemcpy(&R[" << ++mReg << "], &TMP_FLOAT1, sizeof(float));"
<< endl;
}
else if(!negate && nextTokenIs(Token::STRING))
{
dt = STRING;
mGenFile << "\tR[" << ++mReg << "] = (int)\"" << mTok.getString()
<< "\";" << endl;
}
else if(!negate && (nextTokenIs(Token::TRUE) || nextTokenIs(Token::FALSE)))
{
dt = BOOLEAN;
mGenFile << "\tR[" << ++mReg << "] = "
<< (mTok.getType() == Token::TRUE ? "true" : "false") << ";"
<< endl;
}
else
{
return false;
}
return true;
}
bool Parser::term(datatype& dt)
{
datatype dt1, dt2;
if(factor(dt1))
{
int op1 = mReg;
const char* op;
if(term2(dt2, op))
{
if(!equivalentTypes(dt1, dt2) || mArrayID)
{
stringstream m;
m << dtToString(dt1) << " type is not compatible with "
<< dtToString(dt2) << " type";
throwError(m.str());
return false;
}
int op2 = mReg;
doOperation(op1, op2, op, dt1 == FLOAT, dt2 == FLOAT);
}
dt = dt1;
return true;
}
return false;
}
bool Parser::term2(datatype& dt, const char*& op)
{
datatype dt2;
if(nextTokenIs(Token::MULTDIV))
{
op = mTok.getString();
if(factor(dt))
{
int op1 = mReg;
const char* thisOp;
bool lastterm = !term2(dt2, thisOp);
int op2 = mReg;
if(!lastterm)
{
if(!arithOpCompatible(dt, dt2))
{
stringstream m;
m << dtToString(dt) << " type is not compatible with "
<< dtToString(dt2) << " type for arithmetic operations";
throwError(m.str());
return false;
}
doOperation(op1, op2, thisOp, dt == FLOAT, dt2 == FLOAT);
}
return true;
}
}
return false;
}
bool Parser::relation(datatype& dt)
{
datatype dt1, dt2;
if(term(dt1))
{
int op1 = mReg;
const char* op;
if(relation2(dt2, op))
{
if(!equivalentTypes(dt1, dt2) || mArrayID)
{
stringstream m;
m << dtToString(dt1) << " type is not compatible with "
<< dtToString(dt2) << " type for conditional operations";
throwError(m.str());
return false;
}
int op2 = mReg;
doOperation(op1, op2, op);
dt = BOOLEAN;
}
else
dt = dt1;
return true;
}
return false;
}
bool Parser::relation2(datatype& dt, const char*& op)
{
datatype dt2;
if(nextTokenIs(Token::LTE) ||
nextTokenIs(Token::LT) ||
nextTokenIs(Token::GTE) ||
nextTokenIs(Token::GT) ||
nextTokenIs(Token::EQUAL) ||
nextTokenIs(Token::NOTEQUAL))
{
op = mTok.getString();
if(term(dt2))
{
int op1 = mReg;
const char* thisOp;
bool lastrelation = !relation2(dt2, thisOp);
int op2 = mReg;
if(!lastrelation)
{
if(!relationalOpCompatible(dt, dt2))
{
stringstream m;
m << dtToString(dt) << " type is not compatible with "
<< dtToString(dt2) << " type for conditional operations";
throwError(m.str());
return false;
}
doOperation(op1, op2, thisOp);
}
dt = dt2;
return true;
}
}
return false;
}
bool Parser::arithop(datatype& dt)
{
datatype dt1, dt2;
if(relation(dt1))
{
int op1 = mReg;
const char* op;
if(arithop2(dt2, op))
{
if(!equivalentTypes(dt1, dt2) || mArrayID)
{
stringstream m;
m << dtToString(dt1) << " type is not compatible with "
<< dtToString(dt2) << " type for arithmetic operations";
throwError(m.str());
return false;
}
int op2 = mReg;
doOperation(op1, op2, op);
}
dt = dt1;
return true;
}
return false;
}
bool Parser::arithop2(datatype& dt, const char*& op)
{
datatype dt2;
if(nextTokenIs(Token::PLUS) || nextTokenIs(Token::MINUS))
{
op = mTok.getString();
if(relation(dt))
{
int op1 = mReg;
const char* thisOp;
bool lastop = !arithop2(dt2, thisOp);
int op2 = mReg;
if(!lastop)
{
if(!arithOpCompatible(dt, dt2))
{
stringstream m;
m << dtToString(dt) << " type is not compatible with "
<< dtToString(dt2) << " type for arithmetic operations";
throwError(m.str());
return false;
}
doOperation(op1, op2, op);
}
dt = dt2;
return true;
}
}
return false;
}
bool Parser::expression(datatype& dt)
{
datatype dt1, dt2;
bool haveNot = nextTokenIs(Token::NOT);
if(arithop(dt1))
{
int op1 = mReg;
const char* op;
if(expression2(dt2, op))
{
if(!equivalentTypes(dt1, dt2) || mArrayID)
{
stringstream m;
m << dtToString(dt) << " type is not compatible with "
<< dtToString(dt2) << " type";
throwError(m.str());
return false;
}
int op2 = mReg;
doOperation(op1, op2, op);
}
dt = dt1;
if(haveNot and dt == INTEGER)
{
int result = mReg++;
mGenFile << "\tR[" << mReg << "] = ~R[" << result << "];" << endl;
}
return true;
}
return false;
}
bool Parser::expression2(datatype& dt, const char*& op)
{
datatype dt2;
if(nextTokenIs(Token::AND) ||
nextTokenIs(Token::OR))
{
op = mTok.getString();
if(relation(dt))
{
int op1 = mReg;
const char* thisOp;
bool lastexpression = !expression2(dt2, thisOp);
int op2 = mReg;
if(!lastexpression)
{
if(!(dt == dt2 && dt == INTEGER))
{
throwError("operands for bitwise operations must be integers");
return false;
}
doOperation(op1, op2, thisOp);
}
dt = dt2;
return true;
}
}
return false;
}
bool Parser::destination(SymbolTableIt& it, int& index, bool& global)
{
datatype dt;
if(nextTokenIs(Token::IDENTIFIER))
{
const char* id = mTok.getString();
if(nextTokenIs(Token::OPENSQUARE))
{
if(expression(dt))
{
if(dt != INTEGER)
{
throwError("array indexes must be integers");
return false;
}
if(!nextTokenIs(Token::CLOSESQUARE))
return false;
index = mReg;
}
}
if(!lookupSymbol(id, it, global))
{
stringstream m;
m << "symbol \"" << id << "\" not found";
throwError(m.str());
return false;
}
return true;
}
return false;
}
bool Parser::assignmentstatement()
{
datatype dt;
SymbolTableIt s;
bool global;
int index = -1;
if(destination(s, index, global) || mError)
{
if(!nextTokenIs(Token::ASSIGNMENT))
{
stringstream m;
m << "expected \":=\" instead of " << mTok.getString();
throwError(m.str());
return false;
}
if(!expression(dt))
{
throwError("unrecognized expression in assignment");
return false;
}
if(!equivalentTypes(s->second.getDataType(), dt))
{
throwError("invalid assignment; types are not compatible");
return false;
}
// assignment to function means return from function
if(!strcmp(s->second.getID(), currentFunction()))
{
// clean up the stack
SymbolTableIt it = localSymbolTable().begin();
int numLocals = 0;
for(; it != localSymbolTable().end(); ++it)
{
SymbolType st = it->second.getSymbolType();
structuretype structureType = st.getStructureType();
// only clean up our own variables, not parameters
// parameters have a negative offset address
int addr = it->second.getAddr();
if(addr > 0)
{
if((structureType == SCALAR || structureType == FUNCTION))
numLocals++;
else if(structureType == ARRAY)
numLocals += st.getSize();
}
}
if(numLocals > 0)
mGenFile << "\tR[SP] = R[SP] - " << numLocals << ";" << endl;
calleeEnd();
mHaveReturn[mLevel] = true;
}
else
{
int result = mReg;
int addr = s->second.getAddr();
getMemoryLocation(addr, global);
int addrReg = mReg;
if(index != -1)
mGenFile << "\tR[" << addrReg << "] = R[" << addrReg << "] "
<< (addr < 0 ? '-' : '+') << " R[" << index << "];" << endl;
mGenFile << "\tMM[R[" << addrReg << "]] = R[" << result << "];" << endl;
}
return true;
}
return false;
}
bool Parser::statement()
{
return assignmentstatement() ||
ifstatement() ||
loopstatement();
}
bool Parser::functionbody(const char* id)
{
// addr relative to FP
// 1 is stored FP
// 2 is function address
int addr = 3;
SymbolType st;
bool global = false;
while(declaration(addr, st, global) || mError)
{
mError = false;
if(!nextTokenIs(Token::SEMICOLON))
{
throwError("expected ;");
}
else if(!global)
{
if(st.getStructureType() == ARRAY)
addr += st.getSize();
else
addr++;
}
global = false;
st = SymbolType();
}
if(nextTokenIs(Token::BEGIN))
{
mGenFile << id << "_begin:" << endl;
// add any stack variables plus the function address
mGenFile << "\tR[SP] = R[SP] + " << addr - 2 << ";" << endl;
mReg = 0;
// store function addresses
SymbolTableIt it = localSymbolTable().begin();
for(; it != localSymbolTable().end(); ++it)
{
structuretype st = it->second.getStructureType();
if(st == FUNCTION)
{
int addr = it->second.getAddr();
mReg++;
mGenFile << "\tR[" << mReg << "] = " << addr << ";" << endl
<< "\tR[" << mReg << "] = R[" << mReg << "] + R[FP];" << endl
<< "\tMM[R[" << mReg << "]] = (int)&&" << it->second.getID()
<< ";" << endl;
}
}
while(statement() || mError)
{
mError = false;
if(!nextTokenIs(Token::SEMICOLON))
{
throwError("expected ;");
return false;
}
}
if(nextTokenIs(Token::END) && nextTokenIs(Token::FUNCTION))
{
if(!mHaveReturn[mLevel])
{