[libc++abi] Enable demangling of `cp` expression production (#114882)

See itanium-cxx-abi/cxx-abi#196

3 files changed, 41 insertions, 20 deletions

diff --git a/libcxxabi/src/demangle/ItaniumDemangle.h b/libcxxabi/src/demangle/ItaniumDemangle.h
index 52755e6..e4752be 100644
--- a/libcxxabi/src/demangle/ItaniumDemangle.h
+++ b/libcxxabi/src/demangle/ItaniumDemangle.h
@@ -2077,17 +2077,23 @@ public:
 class CallExpr : public Node {
   const Node *Callee;
   NodeArray Args;
+  bool IsParen; // (func)(args ...) ?
 
 public:
-  CallExpr(const Node *Callee_, NodeArray Args_, Prec Prec_)
-      : Node(KCallExpr, Prec_), Callee(Callee_), Args(Args_) {}
+  CallExpr(const Node *Callee_, NodeArray Args_, bool IsParen_, Prec Prec_)
+      : Node(KCallExpr, Prec_), Callee(Callee_), Args(Args_),
+        IsParen(IsParen_) {}
 
   template <typename Fn> void match(Fn F) const {
-    F(Callee, Args, getPrecedence());
+    F(Callee, Args, IsParen, getPrecedence());
   }
 
   void printLeft(OutputBuffer &OB) const override {
+    if (IsParen)
+      OB.printOpen();
     Callee->print(OB);
+    if (IsParen)
+      OB.printClose();
     OB.printOpen();
     Args.printWithComma(OB);
     OB.printClose();
@@ -3354,9 +3360,12 @@ const typename AbstractManglingParser<
      "operator co_await"},
     {"az", OperatorInfo::OfIdOp, /*Type*/ false, Node::Prec::Unary, "alignof "},
     {"cc", OperatorInfo::NamedCast, false, Node::Prec::Postfix, "const_cast"},
-    {"cl", OperatorInfo::Call, false, Node::Prec::Postfix, "operator()"},
+    {"cl", OperatorInfo::Call, /*Paren*/ false, Node::Prec::Postfix,
+     "operator()"},
     {"cm", OperatorInfo::Binary, false, Node::Prec::Comma, "operator,"},
     {"co", OperatorInfo::Prefix, false, Node::Prec::Unary, "operator~"},
+    {"cp", OperatorInfo::Call, /*Paren*/ true, Node::Prec::Postfix,
+     "operator()"},
     {"cv", OperatorInfo::CCast, false, Node::Prec::Cast, "operator"}, // C Cast
     {"dV", OperatorInfo::Binary, false, Node::Prec::Assign, "operator/="},
     {"da", OperatorInfo::Del, /*Ary*/ true, Node::Prec::Unary,
@@ -5099,6 +5108,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseRequiresExpr() {
 //              ::= <binary operator-name> <expression> <expression>
 //              ::= <ternary operator-name> <expression> <expression> <expression>
 //              ::= cl <expression>+ E                                   # call
+//              ::= cp <base-unresolved-name> <expression>* E            # (name) (expr-list), call that would use argument-dependent lookup but for the parentheses
 //              ::= cv <type> <expression>                               # conversion with one argument
 //              ::= cv <type> _ <expression>* E                          # conversion with a different number of arguments
 //              ::= [gs] nw <expression>* _ <type> E                     # new (expr-list) type
@@ -5234,7 +5244,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseExpr() {
         Names.push_back(E);
       }
       return make<CallExpr>(Callee, popTrailingNodeArray(ExprsBegin),
-                            Op->getPrecedence());
+                            /*IsParen=*/Op->getFlag(), Op->getPrecedence());
     }
     case OperatorInfo::CCast: {
       // C Cast: (type)expr
@@ -5421,7 +5431,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseExpr() {
       }
     }
     return make<CallExpr>(Name, popTrailingNodeArray(ExprsBegin),
-                          Node::Prec::Postfix);
+                          /*IsParen=*/false, Node::Prec::Postfix);
   }
 
   // Only unresolved names remain.
diff --git a/libcxxabi/test/test_demangle.pass.cpp b/libcxxabi/test/test_demangle.pass.cpp
index 36f9e07..9e8a7c3 100644
--- a/libcxxabi/test/test_demangle.pass.cpp
+++ b/libcxxabi/test/test_demangle.pass.cpp
@@ -29834,6 +29834,7 @@ const char* cases[][2] =
     {"_ZN5Casts5auto_IiEEvDTnw_DapicvT__EEE", "void Casts::auto_<int>(decltype(new auto((int)())))"},
     {"_ZN5Casts7scalar_IiEEvDTcmcvT__Ecvi_EE", "void Casts::scalar_<int>(decltype((int)(), (int)()))"},
     {"_ZN5test11aIsEEDTcl3foocvT__EEES1_", "decltype(foo((short)())) test1::a<short>(short)"},
+    {"_ZN5test11bIsEEDTcp3foocvT__EEES1_", "decltype((foo)((short)())) test1::b<short>(short)"},
     {"_ZN5test21aIPFfvEEEvT_DTclfL0p_EE", "void test2::a<float (*)()>(float (*)(), decltype(fp()))"},
     {"_ZN5test21bIPFfvEEEDTclfp_EET_", "decltype(fp()) test2::b<float (*)()>(float (*)())"},
     {"_ZN5test21cIPFfvEEEvT_PFvDTclfL1p_EEE", "void test2::c<float (*)()>(float (*)(), void (*)(decltype(fp())))"},
@@ -30397,24 +30398,24 @@ void test_invalid_cases()
     assert(!passed && "demangle did not fail");
 }
 
-const char *xfail_cases[] = {
-    // FIXME: Why does clang generate the "cp" expr?
-    "_ZN5test11bIsEEDTcp3foocvT__EEES1_",
+const char *const xfail_cases[] = {
+    // Sentinel value
+    nullptr
 };
 
-const size_t num_xfails = sizeof(xfail_cases) / sizeof(xfail_cases[0]);
-
 void test_xfail_cases()
 {
     std::size_t len = 0;
     char* buf = nullptr;
-    for (std::size_t i = 0; i < num_xfails; ++i)
+    for (const char *c_str : xfail_cases)
     {
+        if (!c_str)
+            break;
         int status;
-        char* demang = __cxxabiv1::__cxa_demangle(xfail_cases[i], buf, &len, &status);
+        char* demang = __cxxabiv1::__cxa_demangle(c_str, buf, &len, &status);
         if (status != -2)
         {
-            std::printf("%s was documented as xfail but passed\n", xfail_cases[i]);
+            std::printf("%s was documented as xfail but passed\n", c_str);
             std::printf("Got status = %d\n", status);
             assert(status == -2);
         }
diff --git a/llvm/include/llvm/Demangle/ItaniumDemangle.h b/llvm/include/llvm/Demangle/ItaniumDemangle.h
index 3dfe838..7fba3fd 100644
--- a/llvm/include/llvm/Demangle/ItaniumDemangle.h
+++ b/llvm/include/llvm/Demangle/ItaniumDemangle.h
@@ -2077,17 +2077,23 @@ public:
 class CallExpr : public Node {
   const Node *Callee;
   NodeArray Args;
+  bool IsParen; // (func)(args ...) ?
 
 public:
-  CallExpr(const Node *Callee_, NodeArray Args_, Prec Prec_)
-      : Node(KCallExpr, Prec_), Callee(Callee_), Args(Args_) {}
+  CallExpr(const Node *Callee_, NodeArray Args_, bool IsParen_, Prec Prec_)
+      : Node(KCallExpr, Prec_), Callee(Callee_), Args(Args_),
+        IsParen(IsParen_) {}
 
   template <typename Fn> void match(Fn F) const {
-    F(Callee, Args, getPrecedence());
+    F(Callee, Args, IsParen, getPrecedence());
   }
 
   void printLeft(OutputBuffer &OB) const override {
+    if (IsParen)
+      OB.printOpen();
     Callee->print(OB);
+    if (IsParen)
+      OB.printClose();
     OB.printOpen();
     Args.printWithComma(OB);
     OB.printClose();
@@ -3354,9 +3360,12 @@ const typename AbstractManglingParser<
      "operator co_await"},
     {"az", OperatorInfo::OfIdOp, /*Type*/ false, Node::Prec::Unary, "alignof "},
     {"cc", OperatorInfo::NamedCast, false, Node::Prec::Postfix, "const_cast"},
-    {"cl", OperatorInfo::Call, false, Node::Prec::Postfix, "operator()"},
+    {"cl", OperatorInfo::Call, /*Paren*/ false, Node::Prec::Postfix,
+     "operator()"},
     {"cm", OperatorInfo::Binary, false, Node::Prec::Comma, "operator,"},
     {"co", OperatorInfo::Prefix, false, Node::Prec::Unary, "operator~"},
+    {"cp", OperatorInfo::Call, /*Paren*/ true, Node::Prec::Postfix,
+     "operator()"},
     {"cv", OperatorInfo::CCast, false, Node::Prec::Cast, "operator"}, // C Cast
     {"dV", OperatorInfo::Binary, false, Node::Prec::Assign, "operator/="},
     {"da", OperatorInfo::Del, /*Ary*/ true, Node::Prec::Unary,
@@ -5099,6 +5108,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseRequiresExpr() {
 //              ::= <binary operator-name> <expression> <expression>
 //              ::= <ternary operator-name> <expression> <expression> <expression>
 //              ::= cl <expression>+ E                                   # call
+//              ::= cp <base-unresolved-name> <expression>* E            # (name) (expr-list), call that would use argument-dependent lookup but for the parentheses
 //              ::= cv <type> <expression>                               # conversion with one argument
 //              ::= cv <type> _ <expression>* E                          # conversion with a different number of arguments
 //              ::= [gs] nw <expression>* _ <type> E                     # new (expr-list) type
@@ -5234,7 +5244,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseExpr() {
         Names.push_back(E);
       }
       return make<CallExpr>(Callee, popTrailingNodeArray(ExprsBegin),
-                            Op->getPrecedence());
+                            /*IsParen=*/Op->getFlag(), Op->getPrecedence());
     }
     case OperatorInfo::CCast: {
       // C Cast: (type)expr
@@ -5421,7 +5431,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseExpr() {
       }
     }
     return make<CallExpr>(Name, popTrailingNodeArray(ExprsBegin),
-                          Node::Prec::Postfix);
+                          /*IsParen=*/false, Node::Prec::Postfix);
   }
 
   // Only unresolved names remain.