// DND
void CodeGen::visitGMainFuncDec(GMainFuncDec *gmainfuncdec)
{
if(!dontMindMeJustCollectingGlobals) {
curScope = string("main");
emit(".text");
emitLabel("_start");
emit("adr \tsp, \tstackEnd \t@@ setup stack pointer, full descending");
emit("BL rtsinit");
emit("PUSH\t{ip,\tlr}");
//gmainfuncdec->identifier_->accept(this);
//printf("@@ yo, in main regAt(a) and (b) are %d, %d\n",
//regAtName(string("a")), regAtName(string("b") ));
//printf("@@ and in the data structure:\n");
//printf("@@ ...%d, %d\n",
//regVarsInScope[paramsForFunction[string("sum")].front()],
//regVarsInScope[paramsForFunction[string("sum")].back()]);
gmainfuncdec->liststatement_->accept(this);
/*freeRegs(regsInScope);
regsInScope = 0;*/
freeScopeVars();
emitLabel("main_end");
//emit(".end");
emit("\t BL halt\n");
emit("POP \t{ip,\tpc}"); // This line *SHOULD* come first, but whatevs.
}
}
void Else::gen(int b, int a){
int label1 = newLabel();
int label2 = newLabel();
test->jumping(0,label2);
emitLabel(label1);
stmt1->gen(label1, a);
std::stringstream gt;
gt<<"goto L"<<a;
emit(gt.str());
emitLabel(label2);
stmt2->gen(label2,a);
}
// EXPR1 && EXPR2
// DND
void CodeGen::visitCAExprAnd(CAExprAnd *caexprand)
{
curExpr.push(maxExpr++);
int reg1 = allocRegs(1);
string andAfter = getLabel(curScope, "and", maxExpr, "after");
caexprand->conditionalandexpression_->accept(this);
emitCmd("MOV", reg1, 0);
emitCmd("MOV", 0, "#0");
emitCmd("CMP", reg1, 0);
emitCmd("BEQ", andAfter);
emitCmd("MOV", 0, "#1");
caexprand->equalityexpression_->accept(this);
emitCmd("MOV", reg1, 0);
emitCmd("MOV", 0, "#0");
emitCmd("CMP", reg1, 0);
emitCmd("MOVNE", 0, "#1");
emitLabel(andAfter);
curExpr.pop();
freeRegs(1);
}
// DND
void CodeGen::visitGVFuncDec(GVFuncDec *gvfuncdec)
{
gvfuncdec->identifier_->accept(this);
curScope = string(tempString);
if(dontMindMeJustCollectingGlobals) {
// Empty list
paramsForFunction[curScope] = list<string>();
gvfuncdec->listformalparam_->accept(this);
}
if(!dontMindMeJustCollectingGlobals) {
emitLabel(curScope);
emit("PUSH\t{r1-r11, lr}");
int counter = 0;
int formParamHere;
gvfuncdec->listformalparam_->accept(this);
paramNum = 1;
gvfuncdec->block_->accept(this);
freeScopeVars();
cout << curScope << "_end:\n";
emit("POP\t{r1-r11, pc}");
}
}
void Do::gen(int b, int a)
{
after = a;
int label = newLabel();
stmt->gen(b,label);
emitLabel(label);
test->jumping(b,0);
}
/*
* Emit ASC code for a then statment as part of IF-THEN.
* Assumes the corresposding statement or matched_stat code has already
* been emitted.
*/
void emitThenStat() {
/* we don't have a symbol pointer, so just pass in non-null */
CHECK_CAN_EMIT(1);
emitComment("Bottom of IF-THEN as part of IF-THEN");
emitLabel(STMT_LEN, "%s%d",
LABEL_PREFIX, peekLabelStackTop(labelStack));
popLabels(labelStack);
}
/*
* Emit ASC code for an else statement
* Assumes the corresponding statement code is already generated.
*/
void emitElseStat() {
/* we don't have a symbol pointer, so just pass in non-null */
CHECK_CAN_EMIT(1);
emitComment("Bottom of ELSE stat");
emitLabel(STMT_LEN, "%s%d",
LABEL_PREFIX, peekLabelStackTop(labelStack) + 1);
popLabels(labelStack);
}
/*
* Emit code for the end of a while loop.
*/
void emitEndWhile() {
/* we don't have a symbol pointer, so just pass in non-null */
CHECK_CAN_EMIT(1);
emitComment("End of WHILE loop %s%d",
LOOP_PREFIX, peekLabelStackTop(loopLabelStack));
emitLabel(STMT_LEN, "%s%d",
LOOP_PREFIX, peekLabelStackTop(loopLabelStack) + 1);
popLabels(loopLabelStack);
}
void CodeGen::visitEInt(EInt *eint)
{
visitInteger(eint->integer_);
// BOOKMARK
// stringstream temp;
// temp << "#" << tempInt;
// emitCmd("MOV", 0, temp.str());
// THIS IS WHAT'S CAUSING ALL THE SHIT. DEAL WITH IT TOMORROW
string intAfter = getLabel(curScope, "intLit", curDataNum, "after");
string intLabel = getLabel(curScope, "intLit", curDataNum, "data");
cout << "\tB \t" << intAfter << "\n";
emitLabel(intLabel);
cout << ".int\t" << tempInt << "\n";
printf(".align 4\n");
//cout << "\"\n .align 4\n";
emitLabel(intAfter);
cout << "\tLDR \tr12,\t=" << intLabel << "\n";
cout << "\tLDR \tr0,\t [r12]\n";
curDataNum++;
}
void While::gen(int b, int a)
{
after = a;
test->jumping(0,a);
int label = newLabel();
emitLabel(label);
stmt->gen(label,b);
std::stringstream gt;
gt<<"goto L"<<b;
emit(gt.str());
}
/*
* Beginning of a while loop
*/
void emitBeginWhile() {
/* we don't have a symbol pointer, so just pass in non-null */
CHECK_CAN_EMIT(1);
/* Reserve loop labels. One for the top, one for the bottom */
reserveLabels(loopLabelStack, 2);
emitComment("Top of WHILE loop %s%d",
LOOP_PREFIX, peekLabelStackTop(loopLabelStack));
emitLabel(STMT_LEN, "%s%d",
LOOP_PREFIX, peekLabelStackTop(loopLabelStack));
}
// DND
void CodeGen::visitSWhile(SWhile *swhile)
{
if(!dontMindMeJustCollectingGlobals) {
curWhile.push(maxWhile++);
string startWhile = getLabel(curScope, "while", curWhile.top(), "start");
string endWhile = getLabel(curScope, "while", curWhile.top(), "end");
emitLabel(startWhile);
swhile->expression_->accept(this);
emitCmd("CMP", 0, "#0");
emitCmd("BEQ", endWhile);
swhile->statement_->accept(this);
emitCmd("B", startWhile);
emitLabel(endWhile);
curWhile.pop();
}
}
// DND
void CodeGen::visitSIfElse(SIfElse *sifelse)
{
if(!dontMindMeJustCollectingGlobals) {
curIfElse.push(maxIfElse++);
string elseBlock = getLabel(curScope, "ifElse", curIfElse.top(), "elseBlock");
string elseEnd = getLabel(curScope, "ifElse", curIfElse.top(), "end");
sifelse->expression_->accept(this);
emitCmd("CMP", 0, "#0");
emitCmd("BEQ", elseBlock);
sifelse->statement_1->accept(this);
emitCmd("B", elseEnd);
emitLabel(elseBlock);
sifelse->statement_2->accept(this);
emitLabel(elseEnd);
curIfElse.pop();
}
}
/*
* Emit ASC code for a then statment as part of IF-THEN-ELSE.
* Assumes the corresposding statement or matched_stat code has already
* been emitted.
*/
void emitThenMatchedStat() {
/* we don't have a symbol pointer, so just pass in non-null */
CHECK_CAN_EMIT(1);
emitComment("Bottom of an IF-THEN.");
emitComment("Either THEN was executed, so GOTO,");
emitComment("or land at %s%d if 'expr' was false",
LABEL_PREFIX, peekLabelStackTop(labelStack));
emitStmt(STMT_LEN, "GOTO %s%d",
LABEL_PREFIX, peekLabelStackTop(labelStack) + 1);
emitLabel(STMT_LEN, "%s%d",
LABEL_PREFIX, peekLabelStackTop(labelStack));
}
void Seq::gen(int b, int a) {
if (*stmt1 == *Stmt::StmtNULL)
{
stmt2->gen(b, a);
} else if (*stmt2 == *Stmt::StmtNULL)
{
stmt1->gen(b, a);
} else {
int label = newLabel();
stmt1->gen(b, label);
emitLabel(label);
stmt2->gen(label,a);
}
}
// DND
void CodeGen::visitSIf(SIf *sif)
{
if(!dontMindMeJustCollectingGlobals) {
curIf.push(maxIf++);
string endIf = getLabel(curScope, "if", curIf.top(), "end");
sif->expression_->accept(this);
emitCmd("CMP", 0, "#0");
emitCmd("BEQ", endIf);
sif->statement_->accept(this);
emitLabel(endIf);
curIf.pop();
}
}
void If::gen(int b, int a) {
int label = newLabel();
test->jumping(0,a);
emitLabel(label);
stmt->gen(label,a);
}
void processStatement(SymbolTable *table, Node *ptr)
{
Node *p;
char label1[LABEL_SIZE]={0}, label2[LABEL_SIZE]={0};
switch(ptr->token.tokenNumber) {
case COMPOUND_ST:
p = ptr->son->next;
p = p->son;
while (p) {
processStatement(table, p);
p = p->next;
}
break;
case EXP_ST:
if (ptr->son != NULL) {
processOperator(table, ptr->son);
}
break;
case RETURN_ST:
if (ptr->son != NULL) {
p = ptr->son;
if (p->noderep == NONTERM) {
processOperator(table, p);
} else {
rv_emit(table, p);
}
emit0("retv");
} else
emit0("ret");
flag_returned=1;
break;
case IF_ST:
genLabel(label1);
processCondition(table, ptr->son);
emitJump("fjp", label1);
processStatement(table, ptr->son->next);
emitLabel(label1);
break;
case IF_ELSE_ST:
genLabel(label1);
genLabel(label2);
processCondition(table, ptr->son);
emitJump("fjp", label1);
processStatement(table, ptr->son->next);
emitJump("ujp", label2);
emitLabel(label1);
processStatement(table, ptr->son->next->next);
emitLabel(label2);
break;
case WHILE_ST:
genLabel(label1);
genLabel(label2);
emitLabel(label1);
processCondition(table, ptr->son);
emitJump("fjp", label2);
processStatement(table, ptr->son->next);
emitJump("ujp", label1);
emitLabel(label2);
break;
default:
fprintf(file, "not yet implemented.\n");
break;
}
}
void CodeGen::visitFCall(FCall *fcall)
{
if(!dontMindMeJustCollectingGlobals) {
isFCall = true;
// VISIT IDENT, GET FUNCNAME
fcall->identifier_->accept(this);
tempName = tempString;
// Name of func is in tempName
int reg1 = 0;
isRTS = true;
if ((tempName.compare(string("printi")) != 0)
&& (tempName.compare(string("printc")) != 0)
&& (tempName.compare(string("printb")) != 0)
&& (tempName.compare(string("halt")) != 0)
&& (tempName.compare(string("getchar")) != 0)
&& (tempName.compare(string("prints")) != 0))
{
isRTS = false;
}
if(isRTS)
{
//reg1 = allocRegs(1);
//emitCmd("MOV", reg1, 0);
DONT_MOVE = true;
}
}
// GET PARAMETERS
fcall->listexpression_->accept(this);
if(!dontMindMeJustCollectingGlobals) {
regVarStack.push(regVarsInScope);
savedTopReg = topRegister;
topRegister = 1;
bool isPrintS = (tempName.compare(string("prints")) == 0);
bool isGetChar = (tempName.compare(string("getchar")) == 0);
// PRINTS
// PRINTS SPECIAL CASE
string printLabel = getLabel(curScope, "prints", curStringNum, "print");
if(isPrintS) {
cout << "\tMOV\tr12,\tr0\n";
cout << "\tPUSH\t {r1-r12}\n";
cout << "\tB \t" << printLabel << "\n";
string stringLabel = getLabel(curScope, "prints", curStringNum, "string");
emitLabel(stringLabel);
cout << ".ascii\t\"" << replaceEscapes(tempString);
printf("\\0\"\n.align 4\n");
//cout << "\"\n .align 4\n";
emitLabel(printLabel);
cout << "\tLDR \tr0,\t=" << stringLabel << "\n";
curStringNum++;
emitCmd("BL", tempName);
cout << "\tPOP\t {r1-r12}\n";
cout << "\tMOV\tr0,\tr12\n";
}
// ********************CALL THE FUNCTION *******************
else if(isRTS && !isPrintS && !isGetChar) {
cout << "\tMOV\tr12,\tr0\n";
cout << "\tPUSH\t {r1-r12}\n";
emitCmd("BL", tempName);
cout << "\tPOP \t {r1-r12}\n";
cout << "\tMOV\tr0,\tr12\n";
}
else if(isGetChar) {
cout << "\tPUSH\t {r1-r12}\n";
emitCmd("BL", tempName);
cout << "\tPOP \t {r1-r12}\n";
}
else if(!isRTS) {
emitCmd("BL", tempName);
}
// CLEANUP
//if (!isRTS)
//{
regVarsInScope = regVarStack.top();
regVarStack.pop();
topRegister = savedTopReg;
// }
isFCall = false;
}
}
