grammar,compiler: Add Support For Fixed-Width Integers

Distinguishing between signed and unsigned fixed-width integer
types must still be done.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/Common/DataTypes.swift

@@ -424,19 +424,30 @@ public class P4BooleanValue: P4DataValue {
   }
 }
 
+public enum BitWidth: Equatable {
+  case Infinite
+  case Width(Int)
+}
+
 /// A P4 int type
 public struct P4Int: P4Type {
-  public init() {}
+  let width: BitWidth
+
+  public init(_ width: BitWidth = BitWidth.Infinite) {
+    self.width = width
+  }
 
   public var description: String {
-    return "Int"
+    return "Int (width: \(self.width))"
   }
+
   public func eq(rhs: P4Type) -> Bool {
     return switch rhs {
-    case is P4Int: true
+    case let rrhs as P4Int: rrhs.width == self.width
     default: false
     }
   }
+
   public func def() -> P4DataValue? {
     return P4IntValue(withValue: 0)
   }
@@ -444,12 +455,16 @@ public struct P4Int: P4Type {
 
 /// An instance of a P4 integer
 public class P4IntValue: P4DataValue {
+
+  let int_type: P4Int
+
   public func type() -> P4Type {
-    return P4Int()
+    return int_type
   }
 
   let value: Int
-  public init(withValue value: Int) {
+  public init(withValue value: Int, andWidth width: BitWidth = BitWidth.Infinite) {
+    self.int_type = P4Int(width)
     self.value = value
   }
 

Sources/Common/Support.swift

@@ -101,6 +101,8 @@ public func Fold<T, A>(input: [T], initial: A, block: (T, A) -> A) -> A {
   #externalMacro(module: "Macros", type: "RequireNodesType")
 @freestanding(codeItem) public macro SkipUnlessNodeType<N>(node: N, type: String) =
   #externalMacro(module: "Macros", type: "SkipUnlessNodeType")
+@freestanding(codeItem) public macro SkipUnlessNodesTypes<N>(node: N, types: [String]) =
+  #externalMacro(module: "Macros", type: "SkipUnlessNodesTypes")
 
 @freestanding(codeItem) public macro MustOr<E, N>(result: E, thing: E?, or: N) =
   #externalMacro(module: "Macros", type: "MustOr")

Sources/Macros/Macros.swift

@@ -229,6 +229,38 @@ public struct SkipUnlessNodeType: CodeItemMacro {
   }
 }
 
+public struct SkipUnlessNodesTypes: CodeItemMacro {
+  public static func expansion(
+    of node: some FreestandingMacroExpansionSyntax, in context: some MacroExpansionContext
+  ) throws -> [CodeBlockItemSyntax] {
+
+    let arguments = node.arguments.indices
+    var arg_index = arguments.startIndex
+
+    let node_to_check = node.arguments[arg_index].expression
+
+    arg_index = arguments.index(after: arg_index)
+    guard let expected_types = node.arguments[arg_index].expression.as(ArrayExprSyntax.self) else {
+      throw MacroError(withMessage: "Node(s) to check must be in an array")
+    }
+
+    arg_index = arguments.index(after: arg_index)
+
+    let ifs = expected_types.elements.map { l in
+      "\(node_to_check).nodeType != \(l.expression)"
+    }.joined(separator: " && ")
+
+    return [
+      CodeBlockItemSyntax(
+        """
+        if \(raw: ifs) {
+          return Result.Ok(.none)
+        }
+        """)
+    ]
+  }
+}
+
 public struct MustOr: CodeItemMacro {
   public static func expansion(
     of node: some FreestandingMacroExpansionSyntax, in context: some MacroExpansionContext
@@ -261,6 +293,7 @@ public struct MustOr: CodeItemMacro {
 struct P4Macros: CompilerPlugin {
   var providingMacros: [Macro.Type] = [
     RequireResult.self, RequireErrorResult.self, UseOkResult.self, UseErrorResult.self,
-    RequireNodeType.self, SkipUnlessNodeType.self, RequireNodesType.self, MustOr.self,
+    RequireNodeType.self, SkipUnlessNodeType.self, SkipUnlessNodesTypes.self, RequireNodesType.self,
+    MustOr.self,
   ]
 }

Sources/P4Compiler/Expression.swift

@@ -101,9 +101,41 @@ extension P4IntValue: CompilableExpression {
     node: SwiftTreeSitter.Node, withContext context: CompilerContext
   ) -> Result<EvaluatableExpression?> {
     let node = node.child(at: 0)!
-    #SkipUnlessNodeType<SwiftTreeSitter.Node>(node: node, type: "integer")
-    if let parsed_int = Int(node.text!) {
-      return .Ok(P4Value(P4IntValue(withValue: parsed_int)))
+
+    #SkipUnlessNodesTypes<SwiftTreeSitter.Node>(
+      node: node, types: ["integer", "integer_elaborated"])
+
+    var bit_width: BitWidth = BitWidth.Infinite
+    let value_source: String
+    if node.nodeType == "integer_elaborated" {
+      let re = /([0-9]+)([ws])([\-0-9]+)/
+      let integer_components = node.text!.matches(of: re)
+
+      if integer_components.isEmpty || integer_components.count > 1 {
+        return .Error(
+          ErrorWithLocation(
+            sourceLocation: node.toSourceLocation(),
+            withError: "Failed to parse elaborated integer: \(node.text!)"))
+      }
+
+      let width_source = "\(integer_components[0].1)"
+      guard let width = Int(width_source) else {
+        return .Error(
+          ErrorWithLocation(
+            sourceLocation: node.toSourceLocation(),
+            withError: "Failed to parse width from elaborated integer: \(width_source)"))
+      }
+
+      /// TODO: Handle signed vs. unsigned.
+
+      bit_width = BitWidth.Width(width)
+      value_source = "\(integer_components[0].3)"
+    } else {
+      value_source = node.text!
+    }
+
+    if let parsed_int = Int(value_source) {
+      return .Ok(P4Value(P4IntValue(withValue: parsed_int, andWidth: bit_width)))
     } else {
       return .Error(
         ErrorWithLocation(

Sources/P4Compiler/Types.swift

@@ -34,7 +34,42 @@ extension P4Int: CompilableType {
   public static func CompileType(
     type: SwiftTreeSitter.Node, withContext: CompilerContext
   ) -> Common.Result<(any Common.P4Type)?> {
-    return type.text == "int" ? .Ok(P4Int()) : .Ok(.none)
+
+    // Drill down, as appropriate.
+    let base_type_node = type.child(at: 0)!
+    #SkipUnlessNodeType<SwiftTreeSitter.Node>(
+      node: base_type_node, type: "baseType")
+
+    let type_node = base_type_node.child(at: 0)!
+    #SkipUnlessNodeType<SwiftTreeSitter.Node>(
+      node: type_node, type: "int_type")
+
+    var walker = Walker(node: type_node)
+
+    var int_node: Node? = .none
+
+    #MustOr(
+      result: int_node, thing: walker.getNext(),
+      or: Result<P4Type?>.Error(
+        ErrorWithLocation(
+          sourceLocation: type_node.toSourceLocation(),
+          withError: "Missing elements in int type declaration")))
+
+    // Move passed the keyword.
+    walker.next()
+
+    if let bit_width_node = walker.getNext() {
+      guard let bit_width = Int(bit_width_node.child(at: 1)!.text!),
+        bit_width != 0
+      else {
+        return .Error(
+          ErrorWithLocation(
+            sourceLocation: bit_width_node.toSourceLocation(),
+            withError: "Could not parse \(bit_width_node.text!) into integer"))
+      }
+      return .Ok(P4Int(BitWidth.Width(bit_width)))
+    }
+    return .Ok(P4Int())
   }
 }
 

Sources/P4Runtime/CodeGen.swift

@@ -17,6 +17,7 @@
 
 import Common
 import P4Lang
+import P4Protos
 
 public struct Generated {
   let gen: String
@@ -48,13 +49,12 @@ public struct CodeGenerator: LanguageVisitor {
     return visitor.start(node, context: generated)
   }
 
-  /// TODO: Can we generate these implementations somehow?
-
   public typealias Context = Generated
 
   public func visit(
     _ v: Program, _ c: VisitorContext<Generated>
   ) -> Result<VisitorContext<Generated>> {
+
     var result: Result<VisitorContext<Generated>> = Fold(
       input: v.types, initial: .Ok(c.next(uc: c.getUserContext().append("[")))
     ) { (current, acc) in