repaired broken let, letast, letrec handling
This commit is contained in:
@ -145,15 +145,15 @@ procedure Execute (Interp: in out Interpreter_Record) is
|
||||
R := Make_Cons(Interp.Self, Get_Car(Get_Frame_Result(Interp.Stack)), R);
|
||||
|
||||
Clear_Frame_Result (Interp.Stack);
|
||||
if not Is_Cons(S) then
|
||||
if Is_Cons(S) then
|
||||
Set_Cdr (X, R); -- chain the result
|
||||
Set_Car (X, Get_Cdr(S)); -- remember the next <operator> to evaluate
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(S));
|
||||
else
|
||||
-- no more argument to evaluate.
|
||||
-- apply the evaluated arguments to the evaluated operator.
|
||||
Set_Frame_Opcode (Interp.Stack, Opcode_Apply);
|
||||
Set_Frame_Operand (Interp.Stack, Reverse_Cons(R));
|
||||
else
|
||||
Set_Cdr (X, R);
|
||||
Set_Car (X, Get_Cdr(S));
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(S));
|
||||
end if;
|
||||
|
||||
Pop_Tops (Interp, 3);
|
||||
@ -216,56 +216,108 @@ pragma Assert (Get_Cdr(R) = Nil_Pointer);
|
||||
|
||||
procedure Do_Let_Evaluation is
|
||||
pragma Inline (Do_Let_Evaluation);
|
||||
X: Object_Pointer;
|
||||
Y: Object_Pointer;
|
||||
X: aliased Object_Pointer;
|
||||
S: aliased Object_Pointer;
|
||||
R: aliased Object_Pointer;
|
||||
begin
|
||||
X := Get_Frame_Operand(Interp.Stack); -- <bindings> and onward
|
||||
Push_Top (Interp, X'Unchecked_Access);
|
||||
Push_Top (Interp, S'Unchecked_Access);
|
||||
Push_Top (Interp, R'Unchecked_Access);
|
||||
|
||||
if Is_Cons(X) then
|
||||
Set_Frame_Operand (Interp.Stack, Get_Cdr(X));
|
||||
-- Say, <bindings> is ((x 2) (y 2)).
|
||||
-- for the first call, Get_Car(X) is (x 2).
|
||||
-- To get x, Get_Car(Get_Car(X))
|
||||
-- To get 2, Get_Car(Get_Cdr(Get_Car(X)))
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(Get_Cdr(Get_Car(X))));
|
||||
X := Get_Frame_Operand(Interp.Stack);
|
||||
pragma Assert (Is_Array(X));
|
||||
|
||||
R := X.Pointer_Slot(3);
|
||||
if R = Nil_Pointer then
|
||||
-- First call;
|
||||
X.Pointer_Slot(2) := X.Pointer_Slot(1);
|
||||
else
|
||||
-- Pass the result to the Perform_Let_Binding frame.
|
||||
Y := Get_Frame_Result(Interp.Stack);
|
||||
Pop_Frame (Interp);
|
||||
Set_Frame_Result (Interp.Stack, Y);
|
||||
-- Subsequent calls. Store the result in the room created
|
||||
-- in the previous call.
|
||||
pragma Assert (Is_Cons(R));
|
||||
Set_Car (R, Get_Car(Get_Frame_Result(Interp.Stack)));
|
||||
end if;
|
||||
end Do_Let_Evaluation;
|
||||
S := X.Pointer_Slot(2);
|
||||
|
||||
if Is_Cons(S) then
|
||||
-- Handle each binding.
|
||||
|
||||
-- Make an empty room to hold the result on the next call
|
||||
R := Make_Cons (Interp.Self, Nil_Pointer, R);
|
||||
X.Pointer_Slot(3) := R;
|
||||
|
||||
-- Remember the next <operator> to evaluate
|
||||
X.Pointer_Slot(2) := Get_Cdr(S);
|
||||
|
||||
-- Say, <bindings> is ((x 2) (y 2)).
|
||||
-- for the first call, Get_Car(S) is (x 2).
|
||||
-- To get x, Get_Car(Get_Car(S))
|
||||
-- To get 2, Get_Car(Get_Cdr(Get_Car(S)))
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(Get_Cdr(Get_Car(S))));
|
||||
|
||||
else
|
||||
-- No more binding to handle.
|
||||
Pop_Frame (Interp);
|
||||
|
||||
-- The operands at the Let_Evaluation and the Let_Binding frame
|
||||
-- must be the identical objects. this way, i don't need to carry
|
||||
-- over the binding result to the Let_Binding frame.
|
||||
pragma Assert (X = Get_Frame_Operand(Interp.Stack));
|
||||
pragma Assert (Get_Frame_Opcode(Interp.Stack) = Opcode_Let_Binding);
|
||||
--X := Get_Frame_Operand(Interp.Stack);
|
||||
--pragma Assert (Is_Array(X));
|
||||
--pragma Assert (X.Pointer_Slot(3) = Nil_Pointer);
|
||||
--X.Pointer_Slot(3) := R;
|
||||
end if;
|
||||
|
||||
Pop_Tops (Interp, 3);
|
||||
end Do_Let_Evaluation;
|
||||
|
||||
procedure Do_Let_Binding is
|
||||
pragma Inline (Do_Let_Binding);
|
||||
X: aliased Object_Pointer;
|
||||
Y: aliased Object_Pointer;
|
||||
S: aliased Object_Pointer;
|
||||
R: aliased Object_Pointer;
|
||||
begin
|
||||
Push_Top (Interp, X'Unchecked_Access);
|
||||
Push_Top (Interp, Y'Unchecked_Access);
|
||||
Push_Top (Interp, S'Unchecked_Access);
|
||||
Push_Top (Interp, R'Unchecked_Access);
|
||||
|
||||
-- Evaluation of <bindings> is completed.
|
||||
-- Update the environments.
|
||||
X := Get_Frame_Operand(Interp.Stack); -- <bindings> and onward
|
||||
Y := Reverse_Cons(Get_Frame_Result(Interp.Stack));
|
||||
pragma Assert (Is_Array(X));
|
||||
|
||||
while Is_Cons(X) loop
|
||||
pragma Assert (Is_Cons(Y));
|
||||
Put_Environment (Interp, Get_Car(Get_Car(X)), Get_Car(Y));
|
||||
S := X.Pointer_Slot(1);
|
||||
R := X.Pointer_Slot(3);
|
||||
R := Reverse_Cons(R);
|
||||
|
||||
X := Get_Cdr(X);
|
||||
Y := Get_Cdr(Y);
|
||||
while Is_Cons(S) loop
|
||||
pragma Assert (Is_Cons(R));
|
||||
Put_Environment (Interp, Get_Car(Get_Car(S)), Get_Car(R));
|
||||
S := Get_Cdr(S);
|
||||
R := Get_Cdr(R);
|
||||
end loop;
|
||||
|
||||
Pop_Frame (Interp); -- done.
|
||||
pragma Assert (Get_Frame_Opcode(Interp.Stack) = Opcode_Let_Finish);
|
||||
|
||||
Pop_Tops (Interp, 2);
|
||||
Pop_Tops (Interp, 3);
|
||||
end Do_Let_Binding;
|
||||
|
||||
procedure Do_Letast_Binding is
|
||||
pragma Inline (Do_Letast_Binding);
|
||||
X: Object_Pointer;
|
||||
begin
|
||||
X := Get_Frame_Operand(Interp.Stack); -- <bindings> and onward
|
||||
|
||||
-- Don't call this procedure if <bindings> is empty. The caller must ensure this
|
||||
pragma Assert (Is_Cons(X));
|
||||
|
||||
Set_Frame_Opcode (Interp.Stack, Opcode_Letast_Binding_Finish);
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(Get_Cdr(Get_Car(X))));
|
||||
end Do_Letast_Binding;
|
||||
|
||||
procedure Do_Letast_Binding_Finish is
|
||||
pragma Inline (Do_Letast_Binding_Finish);
|
||||
X: aliased Object_Pointer;
|
||||
Y: aliased Object_Pointer;
|
||||
Envir: aliased Object_Pointer;
|
||||
@ -277,40 +329,33 @@ pragma Assert (Get_Cdr(R) = Nil_Pointer);
|
||||
X := Get_Frame_Operand(Interp.Stack); -- <bindings> and onward
|
||||
Y := Get_Frame_Result(Interp.Stack);
|
||||
|
||||
if Y = Nil_Pointer then
|
||||
-- First call
|
||||
pragma Assert (Is_Cons(X)); -- Don't provoke this procedure if <bindings> is empty.
|
||||
Envir := Get_Frame_Environment(Get_Frame_Parent(Interp.Stack));
|
||||
-- Update the environment while evaluating <bindings>
|
||||
|
||||
-- Push a new environment for each binding.
|
||||
Envir := Make_Environment(Interp.Self, Get_Frame_Environment(Interp.Stack));
|
||||
Set_Frame_Environment (Interp.Stack, Envir);
|
||||
Put_Environment (Interp, Get_Car(Get_Car(X)), Get_Car(Y));
|
||||
|
||||
X := Get_Cdr(X); -- next binding
|
||||
if Is_Cons(X) then
|
||||
-- More bingings to evaluate
|
||||
Set_Frame_Operand (Interp.Stack, X);
|
||||
Clear_Frame_Result (Interp.Stack);
|
||||
|
||||
-- the next evaluation must be done in the environment where the
|
||||
-- current binding has been made.
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(Get_Cdr(Get_Car(X))));
|
||||
else
|
||||
-- Subsequence calls. Update the environment while evaluating <bindings>
|
||||
-- No more bingings left
|
||||
Pop_Frame (Interp); -- Done
|
||||
|
||||
-- Push a new environment for each binding.
|
||||
Envir := Make_Environment(Interp.Self, Get_Frame_Environment(Interp.Stack));
|
||||
-- Update the environment of the Let_Finish frame.
|
||||
pragma Assert (Get_Frame_Opcode(Interp.Stack) = Opcode_Let_Finish);
|
||||
Set_Frame_Environment (Interp.Stack, Envir);
|
||||
Put_Environment (Interp, Get_Car(Get_Car(X)), Get_Car(Y));
|
||||
|
||||
X := Get_Cdr(X); -- next binding
|
||||
if Is_Cons(X) then
|
||||
-- More bingings to evaluate
|
||||
Set_Frame_Operand (Interp.Stack, X);
|
||||
Clear_Frame_Result (Interp.Stack);
|
||||
|
||||
-- the next evaluation must be done in the environment where the
|
||||
-- current binding has been made.
|
||||
Push_Frame (Interp, Opcode_Evaluate_Object, Get_Car(Get_Cdr(Get_Car(X))));
|
||||
else
|
||||
-- No more bingings left
|
||||
Pop_Frame (Interp); -- Done
|
||||
|
||||
-- Update the environment of the Let_Finish frame.
|
||||
pragma Assert (Get_Frame_Opcode(Interp.Stack) = Opcode_Let_Finish);
|
||||
Set_Frame_Environment (Interp.Stack, Envir);
|
||||
end if;
|
||||
end if;
|
||||
|
||||
Pop_Tops (Interp, 3);
|
||||
end Do_Letast_Binding;
|
||||
end Do_Letast_Binding_Finish;
|
||||
|
||||
procedure Do_Let_Finish is
|
||||
pragma Inline (Do_Let_Finish);
|
||||
@ -994,6 +1039,8 @@ begin
|
||||
Do_Let_Binding;
|
||||
when Opcode_Letast_Binding =>
|
||||
Do_Letast_Binding;
|
||||
when Opcode_Letast_Binding_Finish =>
|
||||
Do_Letast_Binding_Finish;
|
||||
when Opcode_Let_Evaluation =>
|
||||
Do_Let_Evaluation;
|
||||
when Opcode_Let_Finish =>
|
||||
|
Reference in New Issue
Block a user