[clang] [ASTDump] Add support for structural value template arguments in TextNodeDumper

[sakria9]

Dump structural value in AST.

Example code

template<_Complex int x>
struct E;
template<>
struct E<{1, 2}>;

Command clang++ -Xclang -ast-dump usr.cpp -fsyntax-only -std=c++23

Current AST dump result

|-ClassTemplateDecl 0x61a3b52364e8 <usr.cpp:172:1, line:173:8> col:8 E
| |-NonTypeTemplateParmDecl 0x61a3b52363b8 <line:172:10, col:23> col:23 '_Complex int' depth 0 index 0 x
| |-CXXRecordDecl 0x61a3b5236438 <line:173:1, col:8> col:8 struct E
| `-ClassTemplateSpecialization 0x61a3b5236918 'E'
`-ClassTemplateSpecializationDecl 0x61a3b5236918 <line:174:1, line:175:16> col:8 struct E explicit_specialization
  `-TemplateArgument

After apply this fix

|-ClassTemplateDecl 0x7ce2a834fd60 <usr.cpp:172:1, line:173:8> col:8 E
| |-NonTypeTemplateParmDecl 0x7ce2a834fc10 <line:172:10, col:23> col:23 '_Complex int' depth 0 index 0 x
| |-CXXRecordDecl 0x7ce2a834fca0 <line:173:1, col:8> col:8 struct E
| `-ClassTemplateSpecialization 0x7ce2a8350218 'E'
`-ClassTemplateSpecializationDecl 0x7ce2a8350218 <line:174:1, line:175:16> col:8 struct E explicit_specialization
  `-TemplateArgument structural value '1+2i'

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[llvmbot]

@llvm/pr-subscribers-clang

Author: None (sakria9)

Changes

Dump structural value in AST.

Example code

template<_Complex int x>
struct E;
template<>
struct E<{1, 2}>;

Command clang++ -Xclang -ast-dump usr.cpp -fsyntax-only -std=c++23

Current AST dump result

|-ClassTemplateDecl 0x61a3b52364e8 <usr.cpp:172:1, line:173:8> col:8 E
| |-NonTypeTemplateParmDecl 0x61a3b52363b8 <line:172:10, col:23> col:23 '_Complex int' depth 0 index 0 x
| |-CXXRecordDecl 0x61a3b5236438 <line:173:1, col:8> col:8 struct E
| `-ClassTemplateSpecialization 0x61a3b5236918 'E'
`-ClassTemplateSpecializationDecl 0x61a3b5236918 <line:174:1, line:175:16> col:8 struct E explicit_specialization
  `-TemplateArgument

After apply this fix

|-ClassTemplateDecl 0x7ce2a834fd60 <usr.cpp:172:1, line:173:8> col:8 E
| |-NonTypeTemplateParmDecl 0x7ce2a834fc10 <line:172:10, col:23> col:23 '_Complex int' depth 0 index 0 x
| |-CXXRecordDecl 0x7ce2a834fca0 <line:173:1, col:8> col:8 struct E
| `-ClassTemplateSpecialization 0x7ce2a8350218 'E'
`-ClassTemplateSpecializationDecl 0x7ce2a8350218 <line:174:1, line:175:16> col:8 struct E explicit_specialization
  `-TemplateArgument structural value '1+2i'

---

Full diff: https://github.com/llvm/llvm-project/pull/126341.diff

2 Files Affected:

• (modified) clang/include/clang/AST/TextNodeDumper.h (+1)
• (modified) clang/lib/AST/TextNodeDumper.cpp (+5)

diff --git a/clang/include/clang/AST/TextNodeDumper.h b/clang/include/clang/AST/TextNodeDumper.h
index bfd205ffb0d99a..4b5ad2b5fa74c0 100644
--- a/clang/include/clang/AST/TextNodeDumper.h
+++ b/clang/include/clang/AST/TextNodeDumper.h
@@ -249,6 +249,7 @@ class TextNodeDumper
   void VisitDeclarationTemplateArgument(const TemplateArgument &TA);
   void VisitNullPtrTemplateArgument(const TemplateArgument &TA);
   void VisitIntegralTemplateArgument(const TemplateArgument &TA);
+  void VisitStructuralValueTemplateArgument(const TemplateArgument &TA);
   void VisitTemplateTemplateArgument(const TemplateArgument &TA);
   void VisitTemplateExpansionTemplateArgument(const TemplateArgument &TA);
   void VisitExpressionTemplateArgument(const TemplateArgument &TA);
diff --git a/clang/lib/AST/TextNodeDumper.cpp b/clang/lib/AST/TextNodeDumper.cpp
index 6da1f776b4b635..cb0c742177d2c7 100644
--- a/clang/lib/AST/TextNodeDumper.cpp
+++ b/clang/lib/AST/TextNodeDumper.cpp
@@ -1226,6 +1226,11 @@ void TextNodeDumper::VisitIntegralTemplateArgument(const TemplateArgument &TA) {
   dumpTemplateArgument(TA);
 }
 
+void TextNodeDumper::VisitStructuralValueTemplateArgument(const TemplateArgument &TA) {
+  OS << " structural value";
+  dumpTemplateArgument(TA);
+}
+
 void TextNodeDumper::dumpTemplateName(TemplateName TN, StringRef Label) {
   AddChild(Label, [=] {
     {

[zyn0217]

Thanks for the patch. This needs a test and a release note.

[sakria9]

@zyn0217 Hi, I have added a test and modfied the release note. Please take a look.

Test log:

$ ./bin/llvm-lit ../clang/test/AST/ast-dump-template-argument-structural-value.cpp 
llvm-lit: /workspaces/clice/deps/llvm/llvm/utils/lit/lit/llvm/config.py:506: note: using clang: /workspaces/clice/deps/llvm/build-debug/bin/clang
-- Testing: 1 tests, 1 workers --
PASS: Clang :: AST/ast-dump-template-argument-structural-value.cpp (1 of 1)

Testing Time: 0.22s

Total Discovered Tests: 1
  Passed: 1 (100.00%)

[zyn0217]

Can you consolidate the test into a pre-existing file e.g. AST/ast-dump-templates.cpp?

[sakria9]

Moved.

[sakria9]

@zyn0217 Hi, I have 1) modified the release note 2) moved the test 3) supported dump structural value in JSONNodeDumper.
Please take a look.

[zyn0217]

Thanks

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