Tr_exp Tr_seqExp(Tr_exp* array, int size){
T_exp _pex = (T_exp)checked_malloc(sizeof(struct T_exp_));
T_exp *pex = &_pex;//Always point to the rightmost node in the tree during the spanning
T_exp ex_head;
int i = 0;
int last = size - 1;
while(i<size){
Tr_printTrExp(array[i]);
if(i!=last){
//Not the last one: substitute the rightmost node by T_Eseq (stm-exp pair),
//where stm is the Tr_exp
*pex = T_Eseq(unNx(array[i]), NULL);
} else {
//Last one: substitute the rightmost node by Tr_exp itself
*pex = unEx(array[i]);
}
//In case of first node, remember it
if(i==0){
ex_head = *pex;
}
//Not the last one: let pex point to the rightmost node again
if(i!=last){
pex = &((*pex)->u.ESEQ.exp);
}
i++;
}
//debug("Tr_seqExp done");
return Tr_Ex(ex_head);
}
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_whileExp(Tr_exp cond, Tr_exp body){
debug("Tr_whileExp");
T_stm st;
struct Cx cx_cond = unCx(cond);
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();
doPatch(cx_cond.trues, t);
doPatch(cx_cond.falses, f);
/*
T_Label start
cx_cond.stm (true->t, false->f)
T_Label(t)
body
T_Jump start
T_Label(f)
*/
st = T_Seq(T_Label(start),
T_Seq(cx_cond.stm,
T_Seq(T_Label(t),
T_Seq(unNx(body),
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_ifExp(Tr_exp cond, Tr_exp thenb, Tr_exp elseb){
T_exp ex;
T_stm st;
Tr_exp ret;
struct Cx cx_cond = unCx(cond);
Temp_label t = Temp_newlabel();
Temp_label f = Temp_newlabel();
Temp_label join = Temp_newlabel();
doPatch(cx_cond.trues, t);
doPatch(cx_cond.falses, f);
if(elseb==NULL){
//case 1: if-then
debug("Tr_ifExp: if-then");
st = T_Seq(cx_cond.stm,
T_Seq(T_Label(t),
T_Seq(unNx(thenb),
T_Label(f)
)
)
);
ret = Tr_Nx(st);
} else {
//case 2: if-then-else
if(thenb->kind==Tr_nx && elseb->kind==Tr_nx){
debug("Tr_ifExp: if-then-else (2 nx)");
//special case: two statements
st = T_Seq(cx_cond.stm,
T_Seq(T_Label(t),
T_Seq(unNx(thenb),
T_Seq(
T_Jump(
T_Name(join),
Temp_LabelList(join, NULL)
),
T_Seq(T_Label(f),
T_Seq(unNx(elseb),
T_Label(join)
)
)
)
)
)
);
ret = Tr_Nx(st);
//TODO: special case - two cx.
} else {
debug("Tr_ifExp: if-then-else");
Temp_temp r = Temp_newtemp();
ex = T_Eseq(cx_cond.stm,
T_Eseq(T_Label(t),
T_Eseq(T_Move(T_Temp(r), unEx(thenb)),
T_Eseq(
T_Jump(
T_Name(join),
Temp_LabelList(join, NULL)
),
T_Eseq(T_Label(f),
T_Eseq(T_Move(T_Temp(r), unEx(elseb)),
T_Eseq(T_Label(join),
T_Temp(r)
)
)
)
)
)
)
);
ret = Tr_Ex(ex);
}
}
return ret;
}
void Tr_printTree(Tr_exp exp){
printStmList(stdout, T_StmList(unNx(exp), NULL));
}
//@@@ print Tr_exp
void print(Tr_exp et, FILE * out) {
if (et->kind == Tr_ex) printExp(unEx(et), out);
if (et->kind == Tr_nx) printStm(unNx(et), out);
if (et->kind == Tr_cx) printStm(unCx(et).stm, out);
}
T_stm public_unNx(Tr_exp e) {
return unNx(e);
}
