//Refer to FIGURE 7.4 (P168)
//struct {T_stm left, right;} SEQ; T_stm_
//struct {T_stm stm; T_exp exp;} ESEQ; T_exp_
void Tr_recordExp_app(Tr_exp te, Tr_exp init, bool last){
debug("Tr_recordExp_app %s", last==TRUE?"(LAST)":"");
//1) Retrieve T_stm, which should be an ESEQ
T_exp ex = unEx(te);
//2) Prepare for iteration
//The first sub-node for field initialization
T_stm* right = &(ex->u.ESEQ.stm->u.SEQ.right);
//The register saving the base addr of record var
T_exp temp = ex->u.ESEQ.exp;
//3) Iterate over the SEQs, until the rightmost node is found, which should be NULL
int i = 0;
while(*right!=NULL){
right = &((*right)->u.SEQ.right);
i++;
}
//4) Create a new sub-node to initialize the next field
T_stm move = T_Move(T_Mem(T_Binop(T_plus, temp, T_Const(i*F_wordSize))), unEx(init));
//5) Substitue the rightmode node
if(!last){
*right = T_Seq(move, NULL);
} else {
*right = move;
}
}
T_exp F_Exp(F_access access, T_exp framePtr)
{
if (access->kind == inFrame) {
return T_Mem(T_Binop(T_plus, framePtr, T_Const(access->u.offset)));
} else {
return T_Temp(access->u.reg);
}
}
Tr_exp Tr_arithExp(A_oper oper, Tr_exp left, Tr_exp right){
T_exp exp;
switch(oper){
case A_plusOp:
exp = T_Binop(T_plus, unEx(left), unEx(right));
break;
case A_minusOp:
exp = T_Binop(T_minus, unEx(left), unEx(right));
break;
case A_timesOp:
exp = T_Binop(T_mul, unEx(left), unEx(right));
break;
case A_divideOp:
exp = T_Binop(T_div, unEx(left), unEx(right));
break;
default:
//Should not reach here
printf("Illegal arithmetic operator");
exit(2);
}
return Tr_Ex(exp);
}
Tr_exp Tr_forExp(Tr_exp var, Tr_exp low, Tr_exp high, Tr_exp body){
debug("Tr_forExp");
T_stm st;
T_exp v = unEx(var);
Temp_label t = Temp_newlabel();
Temp_label f = LL_peek();//Get done label from the list, which should have been prepared before this function is called.
Temp_label start = Temp_newlabel();
T_stm cond = T_Cjump(T_le, v, unEx(high), t, f);
/*
T_Move var <- low
T_Label start
T_CJump var <= high, t, f
T_Label(t)
body
T_Move var + 1
T_Jump start
T_Label(f)
*/
st = T_Seq(T_Move(v, unEx(low)),
T_Seq(T_Label(start),
T_Seq(cond,
T_Seq(T_Label(t),
T_Seq(unNx(body),
T_Seq(T_Move(v, T_Binop(T_plus, v, T_Const(1))),
T_Seq(
T_Jump(
T_Name(start),
Temp_LabelList(start, NULL)
),
T_Label(f)
)
)
)
)
)
)
);
//Pop the label as it's no longer used
LL_pop();
return Tr_Nx(st);
}
Tr_exp Tr_arrayVar(Tr_exp base, Tr_exp offset_exp){
return Tr_Ex(T_Mem(T_Binop(T_plus, unEx(base), T_Binop(T_mul, unEx(offset_exp), T_Const(F_wordSize)))));
}
Tr_exp Tr_fieldVar(Tr_exp base, int field_offset){
return Tr_Ex(T_Mem(T_Binop(T_plus, unEx(base), T_Const(field_offset * F_wordSize))));
}
T_exp F_Exp(F_access acc, T_exp framePtr) {
if (acc->kind == inFrame)
return T_Mem(T_Binop(T_plus, T_Const(acc->u.offset), framePtr));
else
return T_Temp(acc->u.reg);
}
