Checl type of _Generic selection

packages/cxx-frontend/src/ASTSlot.ts

@@ -156,105 +156,106 @@ export enum ASTSlot {
   literalOperatorId = 133,
   lparen2Loc = 134,
   lparenLoc = 135,
-  memInitializerList = 136,
-  minusGreaterLoc = 137,
-  moduleDeclaration = 138,
-  moduleLoc = 139,
-  moduleName = 140,
-  modulePartition = 141,
-  moduleQualifier = 142,
-  mutableLoc = 143,
-  namespaceLoc = 144,
-  nestedNameSpecifier = 145,
-  nestedNamespaceSpecifierList = 146,
-  newInitalizer = 147,
-  newLoc = 148,
-  newPlacement = 149,
-  noexceptLoc = 150,
-  noreturnLoc = 151,
-  offsetofLoc = 152,
-  op = 153,
-  opLoc = 154,
-  openLoc = 155,
-  operatorFunctionId = 156,
-  operatorLoc = 157,
-  otherVirtualOrAccessLoc = 158,
-  outputOperandList = 159,
-  parameterDeclarationClause = 160,
-  parameterDeclarationList = 161,
-  privateLoc = 162,
-  privateModuleFragment = 163,
-  ptrOpList = 164,
-  qualifier = 165,
-  qualifierLoc = 166,
-  questionLoc = 167,
-  rangeDeclaration = 168,
-  rangeInitializer = 169,
-  rbraceLoc = 170,
-  rbracket2Loc = 171,
-  rbracketLoc = 172,
-  refLoc = 173,
-  refOp = 174,
-  refQualifierLoc = 175,
-  registerLoc = 176,
-  requirementList = 177,
-  requiresClause = 178,
-  requiresLoc = 179,
-  restrictLoc = 180,
-  returnLoc = 181,
-  rightExpression = 182,
-  rparen2Loc = 183,
-  rparenLoc = 184,
-  scopeLoc = 185,
-  secondColonLoc = 186,
-  semicolonLoc = 187,
-  sizeExpression = 188,
-  sizeofLoc = 189,
-  specifier = 190,
-  specifierLoc = 191,
-  splicer = 192,
-  starLoc = 193,
-  statement = 194,
-  statementList = 195,
-  staticAssertLoc = 196,
-  staticLoc = 197,
-  stringLiteral = 198,
-  stringliteralLoc = 199,
-  switchLoc = 200,
-  symbolicName = 201,
-  symbolicNameLoc = 202,
-  templateArgumentList = 203,
-  templateId = 204,
-  templateLoc = 205,
-  templateParameterList = 206,
-  templateRequiresClause = 207,
-  thisLoc = 208,
-  threadLoc = 209,
-  threadLocalLoc = 210,
-  throwLoc = 211,
-  tildeLoc = 212,
-  trailingReturnType = 213,
-  tryLoc = 214,
-  typeConstraint = 215,
-  typeId = 216,
-  typeIdList = 217,
-  typeLoc = 218,
-  typeQualifierList = 219,
-  typeSpecifier = 220,
-  typeSpecifierList = 221,
-  typeTraitLoc = 222,
-  typedefLoc = 223,
-  typeidLoc = 224,
-  typenameLoc = 225,
-  underlyingTypeLoc = 226,
-  unqualifiedId = 227,
-  usingDeclaratorList = 228,
-  usingLoc = 229,
-  vaArgLoc = 230,
-  virtualLoc = 231,
-  virtualOrAccessLoc = 232,
-  voidLoc = 233,
-  volatileLoc = 234,
-  whileLoc = 235,
-  yieldLoc = 236,
+  matchedAssocIndex = 136,
+  memInitializerList = 137,
+  minusGreaterLoc = 138,
+  moduleDeclaration = 139,
+  moduleLoc = 140,
+  moduleName = 141,
+  modulePartition = 142,
+  moduleQualifier = 143,
+  mutableLoc = 144,
+  namespaceLoc = 145,
+  nestedNameSpecifier = 146,
+  nestedNamespaceSpecifierList = 147,
+  newInitalizer = 148,
+  newLoc = 149,
+  newPlacement = 150,
+  noexceptLoc = 151,
+  noreturnLoc = 152,
+  offsetofLoc = 153,
+  op = 154,
+  opLoc = 155,
+  openLoc = 156,
+  operatorFunctionId = 157,
+  operatorLoc = 158,
+  otherVirtualOrAccessLoc = 159,
+  outputOperandList = 160,
+  parameterDeclarationClause = 161,
+  parameterDeclarationList = 162,
+  privateLoc = 163,
+  privateModuleFragment = 164,
+  ptrOpList = 165,
+  qualifier = 166,
+  qualifierLoc = 167,
+  questionLoc = 168,
+  rangeDeclaration = 169,
+  rangeInitializer = 170,
+  rbraceLoc = 171,
+  rbracket2Loc = 172,
+  rbracketLoc = 173,
+  refLoc = 174,
+  refOp = 175,
+  refQualifierLoc = 176,
+  registerLoc = 177,
+  requirementList = 178,
+  requiresClause = 179,
+  requiresLoc = 180,
+  restrictLoc = 181,
+  returnLoc = 182,
+  rightExpression = 183,
+  rparen2Loc = 184,
+  rparenLoc = 185,
+  scopeLoc = 186,
+  secondColonLoc = 187,
+  semicolonLoc = 188,
+  sizeExpression = 189,
+  sizeofLoc = 190,
+  specifier = 191,
+  specifierLoc = 192,
+  splicer = 193,
+  starLoc = 194,
+  statement = 195,
+  statementList = 196,
+  staticAssertLoc = 197,
+  staticLoc = 198,
+  stringLiteral = 199,
+  stringliteralLoc = 200,
+  switchLoc = 201,
+  symbolicName = 202,
+  symbolicNameLoc = 203,
+  templateArgumentList = 204,
+  templateId = 205,
+  templateLoc = 206,
+  templateParameterList = 207,
+  templateRequiresClause = 208,
+  thisLoc = 209,
+  threadLoc = 210,
+  threadLocalLoc = 211,
+  throwLoc = 212,
+  tildeLoc = 213,
+  trailingReturnType = 214,
+  tryLoc = 215,
+  typeConstraint = 216,
+  typeId = 217,
+  typeIdList = 218,
+  typeLoc = 219,
+  typeQualifierList = 220,
+  typeSpecifier = 221,
+  typeSpecifierList = 222,
+  typeTraitLoc = 223,
+  typedefLoc = 224,
+  typeidLoc = 225,
+  typenameLoc = 226,
+  underlyingTypeLoc = 227,
+  unqualifiedId = 228,
+  usingDeclaratorList = 229,
+  usingLoc = 230,
+  vaArgLoc = 231,
+  virtualLoc = 232,
+  virtualOrAccessLoc = 233,
+  voidLoc = 234,
+  volatileLoc = 235,
+  whileLoc = 236,
+  yieldLoc = 237,
 }

packages/cxx-gen-ast/src/tokens.ts

@@ -197,6 +197,7 @@ export const CXX_KEYWORDS: string[] = [
   "__underlying_type",
   "_Atomic",
   "_Complex",
+  "_Generic",
 ];
 
 export const BUILTIN_TYPE_TRAITS: string[] = [

src/parser/cxx/ast.h

@@ -1344,6 +1344,7 @@ class GenericSelectionExpressionAST final : public ExpressionAST {
   SourceLocation commaLoc;
   List<GenericAssociationAST*>* genericAssociationList = nullptr;
   SourceLocation rparenLoc;
+  int matchedAssocIndex = -1;
 
   void accept(ASTVisitor* visitor) override { visitor->visit(this); }
 

src/parser/cxx/ast_interpreter.cc

@@ -1646,6 +1646,26 @@ auto ASTInterpreter::ExpressionVisitor::operator()(ThisExpressionAST* ast)
 
 auto ASTInterpreter::ExpressionVisitor::operator()(
     GenericSelectionExpressionAST* ast) -> ExpressionResult {
+  if (ast->matchedAssocIndex == -1) return std::nullopt;
+
+  GenericAssociationAST* assoc = nullptr;
+  int index = 0;
+  for (auto assocNode : ListView{ast->genericAssociationList}) {
+    if (index == ast->matchedAssocIndex) {
+      assoc = assocNode;
+      break;
+    }
+    ++index;
+  }
+
+  if (auto def = ast_cast<DefaultGenericAssociationAST>(assoc)) {
+    return accept(def->expression);
+  }
+
+  if (auto entry = ast_cast<TypeGenericAssociationAST>(assoc)) {
+    return accept(entry->expression);
+  }
+
   return std::nullopt;
 }
 

src/parser/cxx/ast_printer.cc

@@ -854,6 +854,10 @@ void ASTPrinter::visit(GenericSelectionExpressionAST* ast) {
                         to_string(ast->type));
   }
   out_ << "\n";
+  ++indent_;
+  out_ << std::format("{:{}}", "", indent_ * 2);
+  out_ << std::format("matched-assoc-index: {}\n", ast->matchedAssocIndex);
+  --indent_;
   accept(ast->expression, "expression");
   if (ast->genericAssociationList) {
     ++indent_;

src/parser/cxx/ast_rewriter.cc

@@ -2489,6 +2489,7 @@ auto ASTRewriter::ExpressionVisitor::operator()(
   }
 
   copy->rparenLoc = ast->rparenLoc;
+  copy->matchedAssocIndex = ast->matchedAssocIndex;
 
   return copy;
 }