/*
* This fucntion commit the second step of the program.
* adding addresses to the three symbol tables.
*/
void secondStep()
{
int memIdx = 0, labelAddress = 0;
IC = 0; DC = 0; lineNumber = 0;
QUE_setPtrToHead();
while(strcmp(QUE_getLabel(),"NULL") != 0 && memIdx != -1)
{
if((labelAddress = getLabelAddress(QUE_getLabel(), labelTABLE)) != -1){
memIdx = setLabelAddressInMemory(memIdx, labelAddress); /* update label address on memory*/
QUE_setIsExtern(FALSE);
}else{
if(getLabelAddress(QUE_getLabel(), externTABLE) == -1)
fprintf(stderr, "\n[line %d]: the label %s is not exists on file ",QUE_getLine(), QUE_getLabel());
else{
QUE_setIsExtern(TRUE);
if(mem[QUE_getLine() + 1].fieldNum == 3 && mem[QUE_getLine() + 1].cml.label.addr == 0){
mem[QUE_getLine() + 1].cml.label.era = 1;
memIdx = QUE_getLine() + 2;
QUE_setLine(QUE_getLine() + 1);
}else{
mem[QUE_getLine() + 2].cml.label.era = 1;
memIdx = QUE_getLine() + 3;
QUE_setLine(QUE_getLine() + 2);
}
}
}
QUE_getNext();
}
seAddressEnEX(entryTABLE);
seAddressEnEX(externTABLE);
}
void Assembler::replaceLabels(){
for(int i=0; i<alignedProgram.size(); i++){
ProgramAtom atom = alignedProgram[i];
if(atom.type == DIRECTIVE_INSTRUCTION){
//Modified replacement
string mnemonic = parser.extractFirstToken(atom.token);
mnemonic = parser.toLower(mnemonic);
bool isBranch = parser.tokenIsBranchInstructionName(mnemonic);
bool isJump = parser.tokenIsJumpInstructionName(mnemonic);
vector<string> instructionTokens = parser.tokenizeInstruction(atom.token);
if(isBranch || isJump){
string lastToken = instructionTokens[instructionTokens.size() - 1];
if(!tokenIsInLabelDB(lastToken)){
//EXCEPTION
string error = ERROR_UNRECOGNIZED_LABEL;
string offendingToken = lastToken;
addException(AssemblerException(*atom.programLine, error, offendingToken));
continue;
}
virtualAddr labelAddr = getLabelAddress(lastToken);
virtualAddr instructionAddr = atom.addr;
virtualAddr immediateVal = 0;
if(isBranch){
int32_t offset = labelAddr - instructionAddr - 4; //pc still increments by 4 on branches
offset >>= 2;
immediateVal = (virtualAddr)offset;
}else if(isJump){
immediateVal = (labelAddr & 0x0FFFFFFF) >> 2;
}
string immediateString = parser.literals.getHexLiteralString(immediateVal);
instructionTokens[instructionTokens.size() - 1] = immediateString;
string newInstructionString = parser.combineInstructionTokens(instructionTokens);
alignedProgram[i].token = newInstructionString;
}else{
/*
Function that updates the label of the operand and it's value from table of signs
Input:
Operand struct
RunStatus struct
integer line Number
Output: True if it was able to update the address , FALSE otherwise
*/
int updateOperandLabelAddress(Operand *op, RunStatus *runStatus, int lineNum)
{
int labelAddress;
int dataAddress;
unsigned int startValueData;
if (op -> type == DIRECT) /*Label is taken from "tag table"*/
{
labelAddress = getLabelAddress(runStatus , op, 1);
if (labelAddress == -1)
{
printf("ERROR: Line #%d, Label \"%s\" doesn't exist.\n", lineNum+1, op->str);
runStatus -> errNum ++;
return FALSE;
}
}
else if ( op -> type == DYNAMIC)
{
labelAddress = getLabelAddress(runStatus , op, 0);
if (labelAddress != -1) /*Parsing the dynamic range*/
{
/* Getting the value depends on cell type (data / command)*/
if (runStatus -> finalLabelArray[labelAddress].isData)
{
dataAddress = runStatus -> finalLabelArray[labelAddress].memAddress - runStatus -> ic - FIRST_MEM_ADDR;
startValueData = runStatus -> dataArray[dataAddress];
}
else
{
startValueData = getIntFromWord(runStatus -> finalLabelArray[labelAddress].word);
}
/* Parsing the specified range*/
op -> val = getRequiredBitsFromLabel(startValueData, op -> up, op-> down);
}
else
{
printf("ERROR: Line #%d, Label \"%s\" doesn't exist.\n", lineNum+1, op->str);
runStatus -> errNum ++;
return FALSE;
}
}
return TRUE;
}
uint32_t handleBranch(Assembler *assembler, char **tokens) {
CondCodes cond = mnemToCondCode(&tokens[0][1]);
uint32_t address = isalpha(tokens[1][0]) ?
//address starts with a char so is a label
getLabelAddress(assembler, tokens[1]) :
//else it's a numeric value
getValue(tokens[1]);
uint32_t offset = calcOffset(assembler, address, true);
return genBranch(cond, offset);
}
/**
* This function checks if the label stands on standards. if it doesn't - the function prints error note.
* ln - the last line.
* returns TRUE if the label is fine, otherwisr - FALSE.
*/
int isLabelOK(line ln)
{
int flag = 0;
if(strcmp(ln.word, "NULL") == 0)
return FALSE;
if(!isalpha(ln.word[0]))
fprintf(stderr, "\n[line %d]: First character of label must be a letter", lineNumber);
else flag++;
if(strlen(ln.word) > maxStringLength)
fprintf(stderr, "\n[line %d]: The label length is longer than the maximum available (%d)",lineNumber, maxStringLength);
else flag++;
if(isRegister(ln.word))
fprintf(stderr, "\n[line %d]: The name of the label %s is equal to register. YOU CANNOT USE THIS NAME", lineNumber , ln.word);
else flag++;
if(getLabelAddress(ln.word, labelTABLE) != -1)
fprintf(stderr, "\n[line %d]: The label %s is already exists on program", lineNumber ,ln.word);
else flag++;
if(flag == 4)
return TRUE;
return FALSE;
}
//Post-processing
void Assembler::pseudoInstructionReplace(){
for(int i=0; i<alignedProgram.size(); i++){
ProgramAtom atom = alignedProgram[i];
string line = atom.token;
if(atom.type == DIRECTIVE_INSTRUCTION){
string mnemonic = parser.extractFirstToken(atom.token);
mnemonic = parser.toLower(mnemonic);
if(parser.tokenIsPseudoInstructionName(mnemonic)){
int pseudoInstructionNumber = parser.getPseudoInstructionNameNumber(mnemonic);
int numInsertedLines = parser.getPseudoInstructionNumberOfLinesToInsert(mnemonic);
vector<string> tokenizedInstruction = parser.tokenizeInstruction(line);
switch(pseudoInstructionNumber){
//TODO: add exceptions for incorrect number of instruction arguments
case 0:
{
//bge $reg1, $reg2, label
if(tokenizedInstruction.size() != 4){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string labelName = tokenizedInstruction[3];
string line1 = "slt\t$at, " + registerName1 + ", " + registerName2;
string line2 = "beq\t$at, $zero, " + labelName;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 1:
{
//bgt $reg1, $reg2, label
if(tokenizedInstruction.size() != 4){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string labelName = tokenizedInstruction[3];
string line1 = "slt\t$at, " + registerName2 + ", " + registerName1;
string line2 = "bne\t$at, $zero, " + labelName;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 2:
{
//ble $reg1, $reg2, label
if(tokenizedInstruction.size() != 4){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string labelName = tokenizedInstruction[3];
string line1 = "slt\t$at, " + registerName2 + ", " + registerName1;
string line2 = "beq\t$at, $zero, " + labelName;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 3:
{
//blt $reg1, $reg2, label
if(tokenizedInstruction.size() != 4){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string labelName = tokenizedInstruction[3];
string line1 = "slt\t$at, " + registerName1 + ", " + registerName2;
string line2 = "bne\t$at, $zero, " + labelName;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 4:
{
//clear $reg
if(tokenizedInstruction.size() != 2){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string line1 = "add\t" + registerName1 + ", $zero, $zero";
alignedProgram[i].token = line1;
}
break;
case 5:
{
//la $reg, label
if(tokenizedInstruction.size() != 3){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string labelName = tokenizedInstruction[2];
if(!tokenIsInLabelDB(labelName)){
//EXCEPTION
string error = ERROR_UNRECOGNIZED_LABEL;
string offendingToken = labelName;
addException(AssemblerException(*atom.programLine, error, offendingToken));
continue;
}
virtualAddr labelAddr = getLabelAddress(labelName);
virtualAddr msb = labelAddr >> (SIZE_BITS_VIRTUAL_ADDR / 2);
virtualAddr lsb = labelAddr & 0x0000FFFF;
string msbHex = parser.literals.getHexLiteralString(msb);
string lsbHex = parser.literals.getHexLiteralString(lsb);
string registerName = tokenizedInstruction[1];
string line1 = "lui\t" + registerName + ", " + msbHex;
string line2 = "ori\t" + registerName + ", " + registerName + ", " + lsbHex;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 6:
{
//li $reg, imm
if(tokenizedInstruction.size() != 3){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string immediateString = tokenizedInstruction[2];
//EXCEPTION
//TODO
uint32_t immediateVal;
try{
immediateVal = parser.literals.getLiteralValue(immediateString);
}catch(InvalidTokenException &e){
string error = ERROR_INVALID_IMMEDIATE_LI;
string offendingToken = immediateString;
addException(AssemblerException(*atom.programLine, error, offendingToken));
continue;
}
virtualAddr msb = immediateVal >> (SIZE_BITS_WORD / 2);
virtualAddr lsb = immediateVal & 0x0000FFFF;
string msbHex = parser.literals.getHexLiteralString(msb);
string lsbHex = parser.literals.getHexLiteralString(lsb);
string registerName = tokenizedInstruction[1];
string line1 = "lui\t" + registerName + ", " + msbHex;
string line2 = "ori\t" + registerName + ", " + registerName + ", " + lsbHex;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 7:
{
//move $reg1, $reg2
if(tokenizedInstruction.size() != 3){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string line1 = "add\t" + registerName1 + ", " + registerName2 + ", $zero";
alignedProgram[i].token = line1;
}
break;
case 8:
{
//neg $reg1, $reg2
if(tokenizedInstruction.size() != 3){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string line1 = "sub\t" + registerName1 + ", $zero, " + registerName2;
alignedProgram[i].token = line1;
}
break;
case 9:
{
//not $reg1, $reg2
if(tokenizedInstruction.size() != 3){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string registerName2 = tokenizedInstruction[2];
string line1 = "addi\t" + registerName1 + ", $zero, -1";
string line2 = "xor\t" + registerName1 + ", " + registerName1 + "," + registerName2;
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
/*
PUSH:
sub $sp,$sp,4
sw $t2,($sp)
POP:
lw $t2,($sp)
addiu $sp,$sp,4
*/
case 10:
{
//push $reg
if(tokenizedInstruction.size() != 2){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string line1 = "sub\t$sp, $sp, 4";
string line2 = "sw\t" + registerName1 + ", 0($sp)";
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 11:
{
//pop $reg
if(tokenizedInstruction.size() != 2){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName1 = tokenizedInstruction[1];
string line1 = "lw\t" + registerName1 + ", 0($sp)";
string line2 = "addi\t$sp, $sp, 4";
alignedProgram[i].token = line1;
alignedProgram[i+1].token = line2;
}
break;
case 12:
{
//peak $reg
if(tokenizedInstruction.size() != 2){addException(AssemblerException(*atom.programLine, ERROR_INVALID_PSEUDOINSTRUCTION, atom.programLine->text));continue;}
string registerName = tokenizedInstruction[1];
string line = "lw\t" + registerName + ", 0($sp)";
alignedProgram[i].token = line;
}
break;
case 13:
{
//rem
}
break;
case 14:
{
//sge
}
break;
case 15:
{
//sgt
}
break;
default:
break;
}
i += numInsertedLines;
}else{
}
}else{
}
}
}
