Refactoring Binder

This commit is contained in:
Michael Schimmel
2025-09-17 15:20:14 +02:00
parent 0cb6f6e85e
commit 4d380c8f98
2 changed files with 51 additions and 66 deletions
+1 -1
View File
@@ -4,7 +4,7 @@
<ProjectVersion>20.3</ProjectVersion>
<FrameworkType>FMX</FrameworkType>
<Base>True</Base>
<Config Condition="'$(Config)'==''">Release</Config>
<Config Condition="'$(Config)'==''">Debug</Config>
<Platform Condition="'$(Platform)'==''">Win64</Platform>
<ProjectName Condition="'$(ProjectName)'==''">ASTPlayground</ProjectName>
<TargetedPlatforms>2</TargetedPlatforms>
+50 -65
View File
@@ -12,7 +12,7 @@ uses
Myc.Ast.Scope;
type
TAstBinder = class(TAstTraverser<Boolean>)
TAstBinder = class(TAstTraverser)
type
TUpvalueMapping = class
Map: TDictionary<TResolvedAddress, Integer>;
@@ -25,12 +25,13 @@ type
FCurrentDescriptor: IScopeDescriptor;
FUpvalueStack: TStack<TUpvalueMapping>;
FNestedLambdaCount: Integer;
FIsTailStack: TStack<Boolean>;
FNextIsTail: Boolean;
procedure EnterScope;
procedure ExitScope;
protected
function EnterNode(const Node: IAstNode): Boolean; override;
function Accept(const Node: IAstNode): TDataValue; override;
public
constructor Create(const AInitialScope: IExecutionScope);
@@ -51,7 +52,6 @@ type
function VisitAssignment(const Node: IAssignmentNode): TDataValue; override;
property CurrentDescriptor: IScopeDescriptor read FCurrentDescriptor;
property NextIsTail: Boolean write FNextIsTail;
end;
implementation
@@ -61,12 +61,6 @@ uses
Myc.Ast;
type
TResolvedAddressComparer = class(TEqualityComparer<TResolvedAddress>)
public
function Equals(const Left, Right: TResolvedAddress): Boolean; override;
function GetHashCode(const Value: TResolvedAddress): Integer; override;
end;
TScopeDescriptor = class(TInterfacedObject, IScopeDescriptor)
private
FParent: IScopeDescriptor;
@@ -84,22 +78,6 @@ type
property Symbols: TDictionary<string, Integer> read FSymbols;
end;
{ TResolvedAddressComparer }
function TResolvedAddressComparer.Equals(const Left, Right: TResolvedAddress): Boolean;
begin
Result := (Left.Kind = Right.Kind) and (Left.ScopeDepth = Right.ScopeDepth) and (Left.SlotIndex = Right.SlotIndex);
end;
function TResolvedAddressComparer.GetHashCode(const Value: TResolvedAddress): Integer;
begin
// Simple combining hash function
Result := 17;
Result := Result * 23 + Ord(Value.Kind);
Result := Result * 23 + Value.ScopeDepth;
Result := Result * 23 + Value.SlotIndex;
end;
{ TAstBinder }
constructor TAstBinder.Create(const AInitialScope: IExecutionScope);
@@ -108,15 +86,31 @@ begin
FCurrentDescriptor := CreateDescriptor(AInitialScope);
FUpvalueStack := TObjectStack<TUpvalueMapping>.Create(true);
FNestedLambdaCount := 0;
FNextIsTail := False;
FIsTailStack := TStack<Boolean>.Create;
// The content of the root node is in a tail position.
FNextIsTail := true;
end;
destructor TAstBinder.Destroy;
begin
FIsTailStack.Free;
FUpvalueStack.Free;
inherited;
end;
function TAstBinder.Accept(const Node: IAstNode): TDataValue;
begin
if not Assigned(Node) or Done then
exit;
FIsTailStack.Push(FNextIsTail);
try
Result := inherited Accept(Node);
finally
FNextIsTail := FIsTailStack.Pop;
end;
end;
class function TAstBinder.Bind(const RootNode: IAstNode; const ParentScope: IExecutionScope): IScopeDescriptor;
var
binder: TAstBinder;
@@ -125,7 +119,7 @@ begin
try
binder.EnterScope;
try
// Start the traversal. The content of the root node is in a tail position.
// Start the traversal
binder.Accept(RootNode);
Result := binder.CurrentDescriptor;
finally
@@ -158,12 +152,6 @@ begin
FCurrentDescriptor := FCurrentDescriptor.Parent;
end;
function TAstBinder.EnterNode(const Node: IAstNode): Boolean;
begin
// The context for the current node is whatever the parent Visit... method prepared.
Result := FNextIsTail;
end;
function TAstBinder.VisitAssignment(const Node: IAssignmentNode): TDataValue;
begin
FNextIsTail := False;
@@ -177,27 +165,24 @@ begin
end;
function TAstBinder.VisitBlockExpression(const Node: IBlockExpressionNode): TDataValue;
var
i: Integer;
begin
for i := 0 to Node.Expressions.Count - 2 do
begin
FNextIsTail := False;
Accept(Node.Expressions[i]);
end;
FNextIsTail := False;
if Node.Expressions.Count > 0 then
var n := Node.Expressions.Count - 1;
for var i := 0 to n do
begin
// The last expression is in a tail position IF the block itself is.
FNextIsTail := Data.Peek;
Accept(Node.Expressions.Last);
if i = n then
FNextIsTail := FIsTailStack.Peek;
Accept(Node.Expressions[i]);
end;
end;
function TAstBinder.VisitFunctionCall(const Node: IFunctionCallNode): TDataValue;
begin
// Annotate this node based on its context, which is on top of the stack.
(Node as TFunctionCallNode).IsTailCall := Data.Peek;
(Node as TFunctionCallNode).IsTailCall := FIsTailStack.Peek;
// Let the default traverser visit children (callee, args), but ensure
// their context is non-tail.
@@ -250,7 +235,7 @@ begin
Accept(Node.Condition);
// The branches are in a tail position if the if-expression itself is.
FNextIsTail := Data.Peek;
FNextIsTail := FIsTailStack.Peek;
Accept(Node.ThenBranch);
if Assigned(Node.ElseBranch) then
Accept(Node.ElseBranch);
@@ -266,14 +251,13 @@ begin
try
EnterScope;
try
(FCurrentDescriptor as TScopeDescriptor).Define('Self');
FCurrentDescriptor.Define('Self');
for param in Node.Parameters do
(FCurrentDescriptor as TScopeDescriptor).Define(param.Name);
FCurrentDescriptor.Define(param.Name);
var lastNestedLambdaCount := FNestedLambdaCount;
// Manually traverse children since we can't call 'inherited' from the simple traverser.
// Parameters are never in a tail position.
FNextIsTail := False;
for param in Node.Parameters do
@@ -290,22 +274,23 @@ begin
end;
finally
var upvalue := FUpvalueStack.Peek;
try
sortedPairs := upvalue.Map.ToArray;
TArray.Sort<TPair<TResolvedAddress, Integer>>(
sortedPairs,
TComparer<TPair<TResolvedAddress, Integer>>.Construct(
function(const Left, Right: TPair<TResolvedAddress, Integer>): Integer begin Result := Left.Value - Right.Value; end
)
);
sortedPairs := upvalue.Map.ToArray;
TArray.Sort<TPair<TResolvedAddress, Integer>>(
sortedPairs,
TComparer<TPair<TResolvedAddress, Integer>>.Construct(
function(const Left, Right: TPair<TResolvedAddress, Integer>): Integer begin Result := Left.Value - Right.Value; end
)
);
SetLength(sourceAddresses, Length(sortedPairs));
for var i := 0 to High(sortedPairs) do
sourceAddresses[i] := sortedPairs[i].Key;
SetLength(sourceAddresses, Length(sortedPairs));
for var i := 0 to High(sortedPairs) do
sourceAddresses[i] := sortedPairs[i].Key;
(Node as TLambdaExpressionNode).Upvalues := sourceAddresses;
FUpvalueStack.Pop;
(Node as TLambdaExpressionNode).Upvalues := sourceAddresses;
finally
FUpvalueStack.Pop;
end;
inc(FNestedLambdaCount);
end;
@@ -318,7 +303,7 @@ begin
Accept(Node.Condition);
// The branches are in a tail position if the ternary expression itself is.
FNextIsTail := Data.Peek;
FNextIsTail := FIsTailStack.Peek;
Accept(Node.ThenBranch);
Accept(Node.ElseBranch);
end;
@@ -338,7 +323,7 @@ begin
if Assigned(Node.Initializer) then
Accept(Node.Initializer);
slotIndex := (FCurrentDescriptor as TScopeDescriptor).Define(Node.Identifier.Name);
slotIndex := FCurrentDescriptor.Define(Node.Identifier.Name);
(Node.Identifier as TIdentifierNode).Address := TResolvedAddress.Create(akLocalOrParent, 0, slotIndex);
FNextIsTail := False;
@@ -412,7 +397,7 @@ end;
constructor TAstBinder.TUpvalueMapping.Create;
begin
inherited Create;
Map := TDictionary<TResolvedAddress, Integer>.Create(TResolvedAddressComparer.Default);
Map := TDictionary<TResolvedAddress, Integer>.Create;
Nodes := TList<IIdentifierNode>.Create();
end;