TranslationTable::MachineInstructionVector
TranslationTable::translateInstruction(
const ir::Instruction* instruction) const
{
auto translation = getTranslation(instruction->opcodeString());
if(translation == nullptr)
{
// Fail the translation by returning nothing
return MachineInstructionVector();
}
return translation->translateInstruction(instruction);
}
/* Function that translates every code and data segment.
* This function returns ASM_OK if everything went good */
int translateCode(t_translation_infos *infos, FILE *fp)
{
int instruction_counter;
t_list *current_instruction;
void *instruction_or_data;
int errorcode;
/* unchecked preconditions: pf and infos are different from NULL */
if (infos->code == NULL)
return ASM_CODE_NOT_PRESENT;
/* initialize the instruction_counter */
instruction_counter = 0;
current_instruction = infos->code;
errorcode = ASM_OK;
/* translate the instruction segment */
while (instruction_counter < infos->codesize)
{
instruction_or_data = LDATA(current_instruction);
assert(instruction_or_data != NULL);
/* translate every single instruction */
errorcode = translateInstruction
(infos, (t_asm_instruction *) instruction_or_data, fp);
/* verify the errorcode */
if (errorcode != ASM_OK)
return errorcode;
/* update the instruction counter and the current instruction data */
instruction_counter++;
current_instruction = LNEXT(current_instruction);
}
#ifndef NDEBUG
fprintf(stderr, "\n");
#endif
/* translate the data segment */
while (current_instruction != NULL)
{
instruction_or_data = LDATA(current_instruction);
assert(instruction_or_data != NULL);
/* translate every single element of data */
#ifndef NDEBUG
fprintf(stderr, "Adding data into the data segment [datatype == %s \t; "
, dataType_toString(((t_asm_data *)instruction_or_data)->dataType) );
fprintf(stderr, "value == 0x%08x] \n"
, ((t_asm_data *)instruction_or_data)->value);
#endif
errorcode = translateData(infos, (t_asm_data *) instruction_or_data, fp);
/* verify the errorcode */
if (errorcode != ASM_OK)
return errorcode;
current_instruction = LNEXT(current_instruction);
}
#ifndef NDEBUG
fprintf(stderr, "\n");
#endif
return ASM_OK;
}
void Translator::generateCode()
{
sourceOutput <<
"void SMBEngine::code(int mode)\n" <<
"{\n" <<
TAB << "switch (mode)\n" <<
TAB << "{\n" <<
TAB << "case 0:\n" <<
TAB << TAB << "loadConstantData();\n" <<
TAB << TAB << "goto Start;\n" <<
TAB << "case 1:\n" <<
TAB << TAB << "goto NonMaskableInterrupt;\n" <<
TAB << "}\n\n";
// Search through the root node, and grab all code label nodes
//
for (std::list<AstNode*>::iterator it = root->children.begin();
it != root->children.end(); ++it)
{
AstNode* node = (*it);
if (node->type != AST_LABEL)
{
continue;
}
LabelNode* label = static_cast<LabelNode*>(node);
if (label->labelType != LABEL_CODE)
{
continue;
}
// Output a C++ label for the label
//
sourceOutput << "\n";
sourceOutput << label->value.s;
// Output a comment, if the label has one
//
if (label->lineNumber != 0)
{
const char* comment = lookupComment(label->lineNumber);
if (comment)
{
// Skip the first character of the ASM comment (;)
//
sourceOutput << " // " << (comment + 1);
}
}
sourceOutput << "\n";
// Translate each piece of code under the label...
//
ListNode* listElement = static_cast<ListNode*>(label->child);
while (listElement != NULL)
{
AstNode* instruction = listElement->value.node;
if (instruction->type == AST_INSTRUCTION)
{
sourceOutput << TAB << translateInstruction(static_cast<InstructionNode*>(instruction));
if (instruction->lineNumber != 0)
{
const char* comment = lookupComment(instruction->lineNumber);
if (comment)
{
// Skip the first character of the ASM comment (;)
//
sourceOutput << " // " << (comment + 1);
}
}
// Add a nice line separator after return statements
//
if (static_cast<InstructionNode*>(instruction)->code == RTS)
{
sourceOutput << "\n\n";
sourceOutput << LINE_SEPARATOR_COMMENT;
}
else
{
// Or just a newline for all other instructions
//
sourceOutput << "\n";
}
if (skipNextInstruction)
{
// If we had a .db $2c instruction immediately before this one,
// we need to add a label to be able to skip this instruction
//
char indexStr[8];
sprintf(indexStr, "%d", skipNextInstructionIndex++);
sourceOutput << "Skip_" << indexStr << ":\n";
skipNextInstruction = false;
}
}
else if (instruction->type == AST_DATA8 &&
strcmp(instruction->value.node->value.node->value.s, "$2c") == 0)
{
// Special case: .db $2c
// We need to goto the next instruction
//
skipNextInstruction = true;
char indexStr[8];
sprintf(indexStr, "%d", skipNextInstructionIndex);
sourceOutput << TAB << "goto Skip_" << indexStr << ";\n";
}
listElement = static_cast<ListNode*>(listElement->next);
}
}
// Generate a return jump table at the end of the code
//
sourceOutput <<
"// Return handler\n" <<
"// This emulates the RTS instruction using a generated jump table\n" <<
"//\n" <<
"Return:\n" <<
TAB << "switch (popReturnIndex())\n" <<
TAB << "{\n";
for (int i = 0; i < returnLabelIndex; i++)
{
char indexStr[8];
sprintf(indexStr, "%d", i);
sourceOutput <<
TAB << "case " << indexStr << ":\n" <<
TAB << TAB << "goto Return_" << indexStr << ";\n";
}
sourceOutput <<
TAB << "}\n";
// Final closing block for the code() function
//
sourceOutput << "}\n";
}
