Error GDCompiler::_parse_block(CodeGen& codegen,const GDParser::BlockNode *p_block,int p_stack_level,int p_break_addr,int p_continue_addr) {
codegen.push_stack_identifiers();
int new_identifiers=0;
codegen.current_line=p_block->line;
for(int i=0;i<p_block->statements.size();i++) {
const GDParser::Node *s = p_block->statements[i];
switch(s->type) {
case GDParser::Node::TYPE_NEWLINE: {
const GDParser::NewLineNode *nl = static_cast<const GDParser::NewLineNode*>(s);
codegen.opcodes.push_back(GDFunction::OPCODE_LINE);
codegen.opcodes.push_back(nl->line);
codegen.current_line=nl->line;
} break;
case GDParser::Node::TYPE_CONTROL_FLOW: {
// try subblocks
const GDParser::ControlFlowNode *cf = static_cast<const GDParser::ControlFlowNode*>(s);
switch(cf->cf_type) {
case GDParser::ControlFlowNode::CF_IF: {
#ifdef DEBUG_ENABLED
codegen.opcodes.push_back(GDFunction::OPCODE_LINE);
codegen.opcodes.push_back(cf->line);
codegen.current_line=cf->line;
#endif
int ret = _parse_expression(codegen,cf->arguments[0],p_stack_level,false);
if (ret<0)
return ERR_PARSE_ERROR;
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP_IF_NOT);
codegen.opcodes.push_back(ret);
int else_addr=codegen.opcodes.size();
codegen.opcodes.push_back(0); //temporary
Error err = _parse_block(codegen,cf->body,p_stack_level,p_break_addr,p_continue_addr);
if (err)
return err;
if (cf->body_else) {
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
int end_addr=codegen.opcodes.size();
codegen.opcodes.push_back(0);
codegen.opcodes[else_addr]=codegen.opcodes.size();
Error err = _parse_block(codegen,cf->body_else,p_stack_level,p_break_addr,p_continue_addr);
if (err)
return err;
codegen.opcodes[end_addr]=codegen.opcodes.size();
} else {
//end without else
codegen.opcodes[else_addr]=codegen.opcodes.size();
}
} break;
case GDParser::ControlFlowNode::CF_FOR: {
int slevel=p_stack_level;
int iter_stack_pos=slevel;
int iterator_pos = (slevel++)|(GDFunction::ADDR_TYPE_STACK<<GDFunction::ADDR_BITS);
int counter_pos = (slevel++)|(GDFunction::ADDR_TYPE_STACK<<GDFunction::ADDR_BITS);
int container_pos = (slevel++)|(GDFunction::ADDR_TYPE_STACK<<GDFunction::ADDR_BITS);
codegen.alloc_stack(slevel);
codegen.push_stack_identifiers();
codegen.add_stack_identifier(static_cast<const GDParser::IdentifierNode*>(cf->arguments[0])->name,iter_stack_pos);
int ret = _parse_expression(codegen,cf->arguments[1],slevel,false);
if (ret<0)
return ERR_COMPILATION_FAILED;
//assign container
codegen.opcodes.push_back(GDFunction::OPCODE_ASSIGN);
codegen.opcodes.push_back(container_pos);
codegen.opcodes.push_back(ret);
//begin loop
codegen.opcodes.push_back(GDFunction::OPCODE_ITERATE_BEGIN);
codegen.opcodes.push_back(counter_pos);
codegen.opcodes.push_back(container_pos);
codegen.opcodes.push_back(codegen.opcodes.size()+4);
codegen.opcodes.push_back(iterator_pos);
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP); //skip code for next
codegen.opcodes.push_back(codegen.opcodes.size()+8);
//break loop
int break_pos=codegen.opcodes.size();
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP); //skip code for next
codegen.opcodes.push_back(0); //skip code for next
//next loop
int continue_pos=codegen.opcodes.size();
codegen.opcodes.push_back(GDFunction::OPCODE_ITERATE);
codegen.opcodes.push_back(counter_pos);
codegen.opcodes.push_back(container_pos);
codegen.opcodes.push_back(break_pos);
codegen.opcodes.push_back(iterator_pos);
Error err = _parse_block(codegen,cf->body,slevel,break_pos,continue_pos);
if (err)
return err;
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(continue_pos);
codegen.opcodes[break_pos+1]=codegen.opcodes.size();
codegen.pop_stack_identifiers();
} break;
case GDParser::ControlFlowNode::CF_WHILE: {
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(codegen.opcodes.size()+3);
int break_addr=codegen.opcodes.size();
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(0);
int continue_addr=codegen.opcodes.size();
int ret = _parse_expression(codegen,cf->arguments[0],p_stack_level,false);
if (ret<0)
return ERR_PARSE_ERROR;
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP_IF_NOT);
codegen.opcodes.push_back(ret);
codegen.opcodes.push_back(break_addr);
Error err = _parse_block(codegen,cf->body,p_stack_level,break_addr,continue_addr);
if (err)
return err;
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(continue_addr);
codegen.opcodes[break_addr+1]=codegen.opcodes.size();
} break;
case GDParser::ControlFlowNode::CF_SWITCH: {
} break;
case GDParser::ControlFlowNode::CF_BREAK: {
if (p_break_addr<0) {
_set_error("'break'' not within loop",cf);
return ERR_COMPILATION_FAILED;
}
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(p_break_addr);
} break;
case GDParser::ControlFlowNode::CF_CONTINUE: {
if (p_continue_addr<0) {
_set_error("'continue' not within loop",cf);
return ERR_COMPILATION_FAILED;
}
codegen.opcodes.push_back(GDFunction::OPCODE_JUMP);
codegen.opcodes.push_back(p_continue_addr);
} break;
case GDParser::ControlFlowNode::CF_RETURN: {
int ret;
if (cf->arguments.size()) {
ret = _parse_expression(codegen,cf->arguments[0],p_stack_level,false);
if (ret<0)
return ERR_PARSE_ERROR;
} else {
ret=GDFunction::ADDR_TYPE_NIL << GDFunction::ADDR_BITS;
}
codegen.opcodes.push_back(GDFunction::OPCODE_RETURN);
codegen.opcodes.push_back(ret);
} break;
}
} break;
case GDParser::Node::TYPE_ASSERT: {
// try subblocks
const GDParser::AssertNode *as = static_cast<const GDParser::AssertNode*>(s);
int ret = _parse_expression(codegen,as->condition,p_stack_level,false);
if (ret<0)
return ERR_PARSE_ERROR;
codegen.opcodes.push_back(GDFunction::OPCODE_ASSERT);
codegen.opcodes.push_back(ret);
} break;
case GDParser::Node::TYPE_LOCAL_VAR: {
const GDParser::LocalVarNode *lv = static_cast<const GDParser::LocalVarNode*>(s);
codegen.add_stack_identifier(lv->name,p_stack_level++);
codegen.alloc_stack(p_stack_level);
new_identifiers++;
} break;
default: {
//expression
int ret = _parse_expression(codegen,s,p_stack_level,true);
if (ret<0)
return ERR_PARSE_ERROR;
} break;
}
}
codegen.pop_stack_identifiers();
return OK;
}
