[PATCH] D129068: [AST] Profiling on constraint expression instead of arguments for TypeConstraint in ASTContext::isSameTemplateParameter

[Chuanqi Xu via Phabricator via cfe-commits]

ChuanqiXu updated this revision to Diff 442181.
ChuanqiXu added a comment.

Add tests for nested template parameters.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129068/new/

https://reviews.llvm.org/D129068

Files:
  clang/lib/AST/ASTContext.cpp
  clang/test/Modules/concept.cppm


Index: clang/test/Modules/concept.cppm
===================================================================
--- clang/test/Modules/concept.cppm
+++ clang/test/Modules/concept.cppm
@@ -18,6 +18,9 @@
 template <class _Tp>
 concept __member_size = requires(_Tp &&t) { t.size(); };
 
+template <class First, class Second>
+concept C = requires(First x, Second y) { x+y; };
+
 struct A {
 public:
   template <Range T>
@@ -29,6 +32,16 @@
   constexpr __integer_like auto operator()(_Tp&& __t) const {
     return __t.size();
   }
+
+  template <__integer_like _Tp, C<_Tp> Sentinel>
+  constexpr _Tp operator()(_Tp &&__t, Sentinel &&last) const {
+    return __t;
+  }
+
+  template <template<class> class H, class S, C<H<S>> Sentinel>
+  constexpr H<S> operator()(H<S> &&__s, Sentinel &&last) const {
+    return __s;
+  }
 };
 #endif
 
@@ -44,6 +57,11 @@
 export module B;
 import A;
 
+template <class T>
+struct U {
+  auto operator+(U) { return 0; }
+};
+
 void foo() {
     A a;
     struct S {
@@ -51,4 +69,7 @@
         auto operator+(S s) { return 0; }
     };
     __fn{}(S());
+    __fn{}(S(), S());
+
+    __fn{}(U<int>(), U<int>());
 }
Index: clang/lib/AST/ASTContext.cpp
===================================================================
--- clang/lib/AST/ASTContext.cpp
+++ clang/lib/AST/ASTContext.cpp
@@ -6245,14 +6245,29 @@
         auto *TYTCArgs = TYTC->getTemplateArgsAsWritten();
         if (TXTCArgs->NumTemplateArgs != TYTCArgs->NumTemplateArgs)
           return false;
-        llvm::FoldingSetNodeID XID, YID;
-        for (auto &ArgLoc : TXTCArgs->arguments())
-          ArgLoc.getArgument().Profile(XID, X->getASTContext());
-        for (auto &ArgLoc : TYTCArgs->arguments())
-          ArgLoc.getArgument().Profile(YID, Y->getASTContext());
-        if (XID != YID)
-          return false;
+        // We couldn't compare the profiling result for the template
+        // args here. Consider the following example in different modules:
+        //
+        // template <__integer_like _Tp, C<_Tp> Sentinel>
+        // constexpr _Tp operator()(_Tp &&__t, Sentinel &&last) const {
+        //   return __t;
+        // }
+        //
+        // When we compare the profiling result for `C<_Tp>` in different
+        // modules, it will compare the type of `_Tp` in different modules.
+        // However, the type of `_Tp` in different modules refer to different
+        // types here naturally. So we couldn't compare the profiling result
+        // for the template args directly.
       }
+      llvm::FoldingSetNodeID XID, YID;
+      auto *XConstraint = TXTC->getImmediatelyDeclaredConstraint();
+      auto *YConstraint = TYTC->getImmediatelyDeclaredConstraint();
+      if (XConstraint)
+        XConstraint->Profile(XID, *this, /*Canonical=*/true);
+      if (YConstraint)
+        YConstraint->Profile(YID, *this, /*Canonical=*/true);
+      if (XID != YID)
+        return false;
     }
     return true;
   }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D129068.442181.patch
Type: text/x-patch
Size: 2950 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20220705/50e5c447/attachment.bin>