Files
gp4/Sources/P4Compiler/Declarations.swift
T
Will Hawkins d971aab1fe Support Calling Parsers With Parameters
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
2026-04-02 01:28:43 -04:00

459 lines
14 KiB
Swift

// p4rse, Copyright 2026, Will Hawkins
//
// This file is part of p4rse.
//
// This file is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
import Common
import P4Lang
import P4Runtime
import SwiftTreeSitter
import TreeSitterExtensions
import TreeSitterP4
extension Declaration: CompilableDeclaration {
public static func Compile(
node: Node, withContext context: CompilerContext
) -> Result<(P4Type, CompilerContext)?> {
guard let node_type = node.nodeType,
node_type == "type_declaration"
else {
return .Ok(.none)
}
// Assume that it is a struct declaration
return StructDeclaration.Compile(node: node.child(at: 0)!, withContext: context)
}
}
struct StructDeclaration {
static func Compile(
node: Node, withContext context: CompilerContext
) -> Result<(P4Type, CompilerContext)?> {
var currentChildIdx = 0
var currentChildIdxSafe = 1
var currentChild: Node? = .none
guard let node_type = node.nodeType,
node_type == "struct_declaration"
else {
return Result.Error(
ErrorOnNode(node: node, withError: "Did not find a struct declaration"))
}
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing elements in struct declaration"))
}
// Skip the keyword struct
currentChildIdx += 1
currentChildIdxSafe += 1
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing elements in struct declaration"))
}
// The name of the struct type.
currentChild = node.child(at: currentChildIdx)
let maybe_struct_identifier = Identifier.Compile(
node: currentChild!, withContext: context)
guard case Result.Ok(let struct_identifier) = maybe_struct_identifier else {
return Result.Error(maybe_struct_identifier.error()!)
}
currentChildIdx += 1
currentChildIdxSafe += 1
// Skip the '{'
currentChildIdx += 1
currentChildIdxSafe += 1
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing element of struct declaration"))
}
currentChild = node.child(at: currentChildIdx)
// If there are no fields, it will be a "}"
if currentChild!.nodeType == "}" {
let struc = P4Struct(withName: struct_identifier, andFields: P4StructFields([]))
return Result.Ok(
(
struc,
context.update(
newTypes: context.types.declare(identifier: struct_identifier, withValue: struc))
))
}
var parse_errs: [Error] = Array()
var current_context = context
var parsed_fields: [P4StructFieldIdentifier] = Array()
if currentChild!.nodeType == "struct_declaration_fields" {
currentChild!.enumerateNamedChildren { declaration_field in
switch VariableDeclarationStatement.Compile(
node: declaration_field, withContext: current_context)
{
case .Ok((let declaration, let updated_context)):
let variable_declaration = declaration as! VariableDeclarationStatement
parsed_fields.append(
P4StructFieldIdentifier(
id: variable_declaration.identifier, withType: variable_declaration.initializer.type()
))
current_context = updated_context
case .Error(let e): parse_errs.append(e)
}
}
}
if !parse_errs.isEmpty {
return .Error(
Error(
withMessage: "Error(s) parsing select cases: "
+ (parse_errs.map { error in
return "\(error.msg)"
}.joined(separator: ";"))))
}
let declared_struct = P4Struct(
withName: struct_identifier, andFields: P4StructFields(parsed_fields))
return .Ok(
(
declared_struct,
current_context.update(
newTypes: current_context.types.declare(
identifier: struct_identifier, withValue: declared_struct))
))
}
}
extension P4Lang.Parser: CompilableDeclaration {
public static func Compile(
node: Node, withContext context: CompilerContext
) -> Result<(P4Type, CompilerContext)?> {
let parser_node = node
#SkipUnlessNodeType<Node, (P4Type, CompilerContext)?>(
node: parser_node, type: "parserDeclaration")
var current_context = context
var currentChildIdx = 0
var currentChildIdxSafe = 1
var currentChild: Node? = .none
if parser_node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: parser_node, withError: "Missing elements of parser declaration"))
}
currentChild = parser_node.child(at: currentChildIdx)
if currentChild!.nodeType != "parserType" {
return .Error(
ErrorOnNode(node: currentChild!, withError: "Missing type for parser declaration"))
}
let type_node = currentChild
var parser_name: Common.Identifier? = .none
// Assume that the parameter list is empty!
var parameter_list = ParameterList()
do {
// Parse the parser type (type_node)
var currentChildIdx = 0
var currentChildIdxSafe = 1
if type_node!.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(
node: parser_node, withError: "Missing elements of parser type in parser declaration"))
}
var currentChild = type_node!.child(at: currentChildIdx)
if currentChild!.nodeType == "annotations" {
return .Error(
ErrorOnNode(
node: currentChild!, withError: "Annotations in parser type are not yet handled."))
// Will increment indexes here.
}
// Skip the parser keyword
currentChildIdx += 1
currentChildIdxSafe += 1
if type_node!.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: type_node!, withError: "Missing name in parser type declaration"))
}
currentChild = type_node?.child(at: currentChildIdx)
switch Identifier.Compile(node: currentChild!, withContext: current_context) {
case .Ok(let id): parser_name = id
case .Error(let e):
return .Error(e)
}
currentChildIdx += 1
currentChildIdxSafe += 1
if type_node!.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: type_node!, withError: "Missing parser parameters"))
}
currentChild = type_node?.child(at: currentChildIdx)
switch ParameterList.Compile(node: currentChild!, withContext: current_context) {
case .Ok(let (parsed_parameter_list, updated_context)):
parameter_list = parsed_parameter_list
current_context = updated_context
case .Error(let e):
return .Error(e)
}
}
// Now, let's put the parameters into scope.
for parameter in parameter_list.parameters {
current_context = current_context.update(
newInstances: current_context.instances.declare(
identifier: parameter.name, withValue: parameter.type))
}
currentChildIdx += 1
currentChildIdxSafe += 1
if parser_node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: parser_node, withError: "Missing parser declaration component"))
}
// Skip the '{'
currentChildIdx += 1
currentChildIdxSafe += 1
if parser_node.childCount < currentChildIdxSafe {
return .Error((Error(withMessage: "Missing body of parser declaration")))
}
currentChild = parser_node.child(at: currentChildIdx)
if currentChild!.nodeType == "parserLocalElements" {
return .Error(
ErrorOnNode(node: currentChild!, withError: "Parser Local Elements are not yet handled."))
// Will increment indexes here.
}
if parser_node.childCount < currentChildIdxSafe {
return .Error((Error(withMessage: "Missing body of parser declaration")))
}
if currentChild!.nodeType != "parserStates" {
return .Error(Error(withMessage: "Missing parser states in parser declaration"))
}
switch Parser.Compile(
withName: parser_name!, withParameters: parameter_list, node: currentChild!,
withContext: current_context)
{
case Result.Ok((let parser, let updated_context)):
// Create a new context with the name of the parser that was just compiled in scope.
return .Ok(
(
parser,
context.update(
newInstances: updated_context.instances.declare(
identifier: parser.name, withValue: parser))
))
case Result.Error(let error): return .Error(error)
}
}
}
func parameter_list_compiler(
node: SwiftTreeSitter.Node, withContext context: CompilerContext
) -> Common.Result<(ParameterList, CompilerContext)> {
var currentChildIdx = 0
var currentChildIdxSafe = 1
var currentChild: Node? = .none
if node.text == ")" {
// There are no parameters!
return Result.Ok((ParameterList([]), context))
}
#RequireNodeType<Node, (ParameterList, CompilerContext)>(
node: node, type: "parameter_list", nice_type_name: "Parameter List")
var parameters: ParameterList = ParameterList([])
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing parameter list component"))
}
currentChild = node.child(at: currentChildIdx)
if currentChild?.nodeType == "parameter_list" {
switch parameter_list_compiler(node: currentChild!, withContext: context) {
case .Ok(let (ps, _)):
parameters = ps
case .Error(let e): return Result.Error(e)
}
currentChildIdx += 1
currentChildIdxSafe += 1
}
// We may have moved nodes, check/reset currentChild.
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing parameter list component"))
}
currentChild = node.child(at: currentChildIdx)
// If this is a ')', we are done.
if currentChild?.text == ")" {
return Result.Ok((parameters, context))
}
// If this is a comma, we skip it!
if currentChild?.text == "," {
currentChildIdx += 1
currentChildIdxSafe += 1
}
if node.childCount < currentChildIdxSafe {
return Result.Error(
ErrorOnNode(node: node, withError: "Missing parameter list component"))
}
currentChild = node.child(at: currentChildIdx)
// Otherwise, there should be one parameter left!
switch Parameter.Compile(node: currentChild!, withContext: context) {
case .Ok(let (vds, updated_context)):
return Result.Ok((parameters.addParameter(vds), updated_context))
case .Error(let e): return Result.Error(e)
}
}
extension ParameterList: Compilable {
public typealias T = ParameterList
public static func Compile(
node: SwiftTreeSitter.Node, withContext context: CompilerContext
) -> Common.Result<(ParameterList, CompilerContext)> {
let parameter_node = node
#RequireNodeType<Node, (ParameterList, CompilerContext)>(
node: parameter_node, type: "parameters", nice_type_name: "Parameters")
var currentChildIdx = 0
var currentChildIdxSafe = 1
// Let's eat the '(' before we start ...
if parameter_node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: parameter_node, withError: "Missing '(' in parameter list component"))
}
currentChildIdx += 1
currentChildIdxSafe += 1
if parameter_node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: parameter_node, withError: "Missing parameter list component"))
}
let currentChild = parameter_node.child(at: currentChildIdx)
return parameter_list_compiler(node: currentChild!, withContext: context)
}
}
extension Parameter: Compilable {
public typealias T = Parameter
public static func Compile(
node: Node, withContext context: CompilerContext
) -> Result<(Parameter, CompilerContext)> {
#RequireNodeType<Node, (EvaluatableStatement, CompilerContext)>(
node: node, type: "parameter", nice_type_name: "parameter")
var currentChildIdx = 0
var currentChildIdxSafe = 1
var currentChild: Node? = .none
if node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: node, withError: "Missing parameter declaration component"))
}
currentChild = node.child(at: currentChildIdx)
// Annotation?
if currentChild!.nodeType == "annotations" {
return .Error(
ErrorOnNode(
node: currentChild!,
withError: "Annotations in parameter declarations are not yet handled"))
// Will increment indexes here.
}
// Direction?
if currentChild!.nodeType == "direction" {
return .Error(
ErrorOnNode(
node: currentChild!, withError: "Direction in parameter declarations are not yet handled"
))
// Will increment indexes here.
}
if currentChild!.nodeType != "typeRef" {
return Result.Error(
ErrorOnNode(
node: node, withError: "Did not find type name for parameter declaration"))
}
guard
case .Ok(let parameter_type) = Types.CompileType(type: currentChild!, withContext: context)
else {
return Result.Error(
Error(withMessage: "Could not parse a P4 type from \(currentChild!.text!)"))
}
currentChildIdx += 1
currentChildIdxSafe += 1
if node.childCount < currentChildIdxSafe {
return .Error(
ErrorOnNode(node: node, withError: "Missing parameter declaration component"))
}
currentChild = node.child(at: currentChildIdx)
if currentChild!.nodeType != "identifier" {
return Result.Error(
ErrorOnNode(
node: node, withError: "Did not find identifier for parameter statement"))
}
guard
case .Ok(let parameter_name) = Identifier.Compile(node: currentChild!, withContext: context)
else {
return Result.Error(
Error(withMessage: "Could not parse a parameter name from \(currentChild!.text!)"))
}
return Result.Ok(
(
Parameter(
identifier: parameter_name, withType: parameter_type),
context
))
}
}