Tr_exp Tr_assignExp(Tr_exp lvalue, Tr_exp right){
debug("Tr_assignExp");
if(right!=NULL){
return Tr_Nx(T_Move(unEx(lvalue), unEx(right)));
} else {
return lvalue;
}
}
Tr_exp Tr_breakExp(){
//Get done label from the list, which should have been prepared before this function is called.
Temp_label f = LL_peek();
T_stm st =
T_Jump(
T_Name(f),
Temp_LabelList(f, NULL)
);
return Tr_Nx(st);
}
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);
}
void print_frag(F_fragList fl, FILE * out) {
if (!fl) {
puts("fragList is NULL");
return;
}
while (fl) {
F_frag f = fl->head;
switch(f->kind) {
case F_stringFrag:
print(Tr_Ex(T_Name(f->u.string.label)), out);
fprintf(out, "\n");
break;
case F_procFrag:
print(Tr_Nx(f->u.proc.body), out);
break;
default: assert(0 && "frag-kind is error");
}
fl = fl->tail;
}
}
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;
}
