[AST] Dump argument types for TypeTraitExpr.

[hokein]

The argument types are not modeled as children of TypeTraitExpr, therefore they are not dumped with the default implementation.

Dumping them is really useful for ad-hoc debugging, context #89358

[llvmbot]

@llvm/pr-subscribers-clang

Author: Haojian Wu (hokein)

Changes

The argument types are not modeled as children of TypeTraitExpr, therefore they are not dumped with the default implementation.

Dumping them is really useful for ad-hoc debugging, context #89358

---

Full diff: https://github.com/llvm/llvm-project/pull/89370.diff

3 Files Affected:

• (modified) clang/include/clang/AST/ASTNodeTraverser.h (+6)
• (modified) clang/test/AST/ast-dump-template-json-win32-mangler-crash.cpp (+38-2)
• (modified) clang/test/AST/ast-dump-traits.cpp (+9)

diff --git a/clang/include/clang/AST/ASTNodeTraverser.h b/clang/include/clang/AST/ASTNodeTraverser.h
index f5c47d8a7c2113..216dc9eef08b62 100644
--- a/clang/include/clang/AST/ASTNodeTraverser.h
+++ b/clang/include/clang/AST/ASTNodeTraverser.h
@@ -851,6 +851,12 @@ class ASTNodeTraverser
       Visit(R);
   }
 
+  void VisitTypeTraitExpr(const TypeTraitExpr *E) {
+    // Argument types are not children of the TypeTraitExpr.
+    for (auto *A : E->getArgs())
+      Visit(A->getType());
+  }
+
   void VisitLambdaExpr(const LambdaExpr *Node) {
     if (Traversal == TK_IgnoreUnlessSpelledInSource) {
       for (unsigned I = 0, N = Node->capture_size(); I != N; ++I) {
diff --git a/clang/test/AST/ast-dump-template-json-win32-mangler-crash.cpp b/clang/test/AST/ast-dump-template-json-win32-mangler-crash.cpp
index 8c03b58abb0edb..cf740516db6f4b 100644
--- a/clang/test/AST/ast-dump-template-json-win32-mangler-crash.cpp
+++ b/clang/test/AST/ast-dump-template-json-win32-mangler-crash.cpp
@@ -2725,7 +2725,25 @@ int main()
 // CHECK-NEXT:        "type": {
 // CHECK-NEXT:         "qualType": "bool"
 // CHECK-NEXT:        },
-// CHECK-NEXT:        "valueCategory": "prvalue"
+// CHECK-NEXT:        "valueCategory": "prvalue",
+// CHECK-NEXT:        "inner": [
+// CHECK-NEXT:         {
+// CHECK-NEXT:          "id": "0x{{.*}}",
+// CHECK-NEXT:          "kind": "TemplateTypeParmType",
+// CHECK-NEXT:          "type": {
+// CHECK-NEXT:           "qualType": "_Ty"
+// CHECK-NEXT:          },
+// CHECK-NEXT:          "isDependent": true,
+// CHECK-NEXT:          "isInstantiationDependent": true,
+// CHECK-NEXT:          "depth": 0,
+// CHECK-NEXT:          "index": 0,
+// CHECK-NEXT:          "decl": {
+// CHECK-NEXT:           "id": "0x{{.*}}",
+// CHECK-NEXT:           "kind": "TemplateTypeParmDecl",
+// CHECK-NEXT:           "name": "_Ty"
+// CHECK-NEXT:          }
+// CHECK-NEXT:         }
+// CHECK-NEXT:        ]
 // CHECK-NEXT:       }
 // CHECK-NEXT:      ]
 // CHECK-NEXT:     }
@@ -3003,7 +3021,25 @@ int main()
 // CHECK-NEXT:        "type": {
 // CHECK-NEXT:         "qualType": "bool"
 // CHECK-NEXT:        },
-// CHECK-NEXT:        "valueCategory": "prvalue"
+// CHECK-NEXT:        "valueCategory": "prvalue",
+// CHECK-NEXT:        "inner": [
+// CHECK-NEXT:         {
+// CHECK-NEXT:          "id": "0x{{.*}}",
+// CHECK-NEXT:          "kind": "TemplateTypeParmType",
+// CHECK-NEXT:          "type": {
+// CHECK-NEXT:           "qualType": "_Ty"
+// CHECK-NEXT:          },
+// CHECK-NEXT:          "isDependent": true,
+// CHECK-NEXT:          "isInstantiationDependent": true,
+// CHECK-NEXT:          "depth": 0,
+// CHECK-NEXT:          "index": 0,
+// CHECK-NEXT:          "decl": {
+// CHECK-NEXT:           "id": "0x{{.*}}",
+// CHECK-NEXT:           "kind": "TemplateTypeParmDecl",
+// CHECK-NEXT:           "name": "_Ty"
+// CHECK-NEXT:          }
+// CHECK-NEXT:         }
+// CHECK-NEXT:        ]
 // CHECK-NEXT:       }
 // CHECK-NEXT:      ]
 // CHECK-NEXT:     }
diff --git a/clang/test/AST/ast-dump-traits.cpp b/clang/test/AST/ast-dump-traits.cpp
index 99ad50f528eb79..3085e5883fd2e2 100644
--- a/clang/test/AST/ast-dump-traits.cpp
+++ b/clang/test/AST/ast-dump-traits.cpp
@@ -40,10 +40,19 @@ void test_unary_expr_or_type_trait() {
 // CHECK-NEXT: |   | `-EnumDecl {{.*}} <col:3, col:11> col:8{{( imported)?}} referenced E
 // CHECK-NEXT: |   |-CStyleCastExpr {{.*}} <line:13:3, col:21> 'void' <ToVoid>
 // CHECK-NEXT: |   | `-TypeTraitExpr {{.*}} <col:10, col:21> 'bool' __is_enum
+// CHECK-NEXT: |   |   `-ElaboratedType {{.*}} 'E' sugar
+// CHECK-NEXT: |   |     `-EnumType {{.*}} 'E'
+// CHECK-NEXT: |   |       `-Enum {{.*}} 'E'
 // CHECK-NEXT: |   |-CStyleCastExpr {{.*}} <line:15:3, col:30> 'void' <ToVoid>
 // CHECK-NEXT: |   | `-TypeTraitExpr {{.*}} <col:10, col:30> 'bool' __is_same
+// CHECK-NEXT: |   |   |-BuiltinType {{.*}} 'int'
+// CHECK-NEXT: |   |   `-BuiltinType {{.*}} 'float'
 // CHECK-NEXT: |   `-CStyleCastExpr {{.*}} <line:17:3, col:47> 'void' <ToVoid>
 // CHECK-NEXT: |     `-TypeTraitExpr {{.*}} <col:10, col:47> 'bool' __is_constructible
+// CHECK-NEXT:         |-BuiltinType {{.*}} 'int'
+// CHECK-NEXT:         |-BuiltinType {{.*}} 'int'
+// CHECK-NEXT:         |-BuiltinType {{.*}} 'int'
+// CHECK-NEXT:         `-BuiltinType {{.*}} 'int'
 // CHECK-NEXT: |-FunctionDecl {{.*}} <line:20:1, line:23:1> line:20:6{{( imported)?}} test_array_type_trait 'void ()'
 // CHECK-NEXT: | `-CompoundStmt {{.*}} <col:30, line:23:1>
 // CHECK-NEXT: |   `-CStyleCastExpr {{.*}} <line:22:3, col:34> 'void' <ToVoid>

[erichkeane]

It seems to me that exposing these as children is the better option here, right? That way it would better model a CallExpr or template type-trait, and would work in our StmtProfiler et-al.

[hokein]

It seems to me that exposing these as children is the better option here, right? That way it would better model a CallExpr or template type-trait, and would work in our StmtProfiler et-al.

Agree that exposing them as children is better. However, we encounter an implementation limitation.

For Expr subclasses, their children must be a Stmt. The TypeTraitExpr doesn't meet this requirement because its arguments are types TypeSourceInfo.