Save/restore OuterTemplateParams in AbstractManglingParser::parseEncoding.

[ldionne]

Summary

Previously we were only saving plain TemplateParams.

[jlebar]

@rsmith I have no idea if the other test change is correct, and gnu cxxfilt doesn't work with that mangled name. Hope this doesn't actually break something...

[jlebar]

Thank you for the review, Richard!

[rsmith]

libcxxabi/test/test_demangle.pass.cpp

29595

It's suspicious that spclsr3stdE7forwardIT_Efp_EE appears here but there's no corresponding call to std::forward<...> whatsoever in the demangling any more. Demangling this by hand I get:

template<typename ...T>
auto Ncr::Silver::Utility::detail::CallOnThread<X::$_5>::operator()(T &&...params) const
  -> decltype(F()(std::forward<T>(params) ...))

where X is the (presumably) Objective C symbol -[DeploymentSetupController handleManualServerEntry:]
and F is X::$_5 &Ncr::Silver::Utility::detail::getT<X::$_5>()
and T is an empty pack

So: it's right that std::forward disappears: it's within a pack expansion that was expanded zero times. And the new demangling appears to be correct.

[ldionne]

Just stumbled upon this while looking at the review queue. Can you briefly explain what this change is about? How is this changing the behavior of the demangler? I don't see something wrong with the patch, but I also don't understand it so..

[ldionne]

Also, rebasing onto main would be nice as it would trigger CI again. It would be good to have green CI on this.

[ldionne]

Closing since this already landed as c962491a41c3fbc6de50b4c109a67d21b2044d71.

libcxxabi/src/demangle/ItaniumDemangle.h

   class SaveTemplateParams {
     AbstractManglingParser *Parser;
     decltype(TemplateParams) OldParams;
+    decltype(OuterTemplateParams) OldOuterParams;
 
   public:
     SaveTemplateParams(AbstractManglingParser *TheParser) : Parser(TheParser) {
       OldParams = std::move(Parser->TemplateParams);
+      OldOuterParams = std::move(Parser->OuterTemplateParams);
       Parser->TemplateParams.clear();
+      Parser->OuterTemplateParams.clear();
     }
     ~SaveTemplateParams() {
       Parser->TemplateParams = std::move(OldParams);
+      Parser->OuterTemplateParams = std::move(OldOuterParams);
     }
   } SaveTemplateParams(this);
 

libcxxabi/test/test_demangle.pass.cpp

     {"_Z1fPU11objcproto1A11objc_object", "f(id<A>)"},
     {"_Z1fPKU11objcproto1A7NSArray", "f(NSArray<A> const*)"},
     {"_ZNK1AIJ1Z1Y1XEEcv1BIJDpPT_EEIJS2_S1_S0_EEEv", "A<Z, Y, X>::operator B<X*, Y*, Z*><X, Y, Z>() const"},
-    {"_ZNK3Ncr6Silver7Utility6detail12CallOnThreadIZ53-[DeploymentSetupController handleManualServerEntry:]E3$_5EclIJEEEDTclclL_ZNS2_4getTIS4_EERT_vEEspclsr3stdE7forwardIT_Efp_EEEDpOSA_", "decltype(-[DeploymentSetupController handleManualServerEntry:]::$_5& Ncr::Silver::Utility::detail::getT<-[DeploymentSetupController handleManualServerEntry:]::$_5>()()(std::forward<-[DeploymentSetupController handleManualServerEntry:]::$_5>(fp)...)) Ncr::Silver::Utility::detail::CallOnThread<-[DeploymentSetupController handleManualServerEntry:]::$_5>::operator()<>(-[DeploymentSetupController handleManualServerEntry:]::$_5&&...) const"},
+    {"_ZNK3Ncr6Silver7Utility6detail12CallOnThreadIZ53-[DeploymentSetupController handleManualServerEntry:]E3$_5EclIJEEEDTclclL_ZNS2_4getTIS4_EERT_vEEspclsr3stdE7forwardIT_Efp_EEEDpOSA_", "decltype(-[DeploymentSetupController handleManualServerEntry:]::$_5& Ncr::Silver::Utility::detail::getT<-[DeploymentSetupController handleManualServerEntry:]::$_5>()()()) Ncr::Silver::Utility::detail::CallOnThread<-[DeploymentSetupController handleManualServerEntry:]::$_5>::operator()<>() const"},
     {"_Zli2_xy", "operator\"\" _x(unsigned long long)"},
     {"_Z1fIiEDcT_", "decltype(auto) f<int>(int)"},
     {"_ZZ4testvEN1g3fooE5Point", "test()::g::foo(Point)"},

     {"_Z1fIL4Enumn1EEvv", "void f<(Enum)-1>()"},
 
     {"_ZN1A1gIiEEDTcldtptfpT1b1fIT_EEEv", "decltype(this->b.f<int>()) A::g<int>()"},
+
+    {"_ZN3xxx3yyyIvNS_1AILm0EEEZNS_2bb2cc2ddILNS_1eE1EEEvRKNS_1fERKNS_1g1hINS_1iEEERKNS_1jEfRKNS_1kEiPhEUlvE_JEEEvT1_DpT2_", "void xxx::yyy<void, xxx::A<0ul>, void xxx::bb::cc::dd<(xxx::e)1>(xxx::f const&, xxx::g::h<xxx::i> const&, xxx::j const&, float, xxx::k const&, int, unsigned char*)::'lambda'()>(void xxx::bb::cc::dd<(xxx::e)1>(xxx::f const&, xxx::g::h<xxx::i> const&, xxx::j const&, float, xxx::k const&, int, unsigned char*)::'lambda'())"},
+
 };
 
 const unsigned N = sizeof(cases) / sizeof(cases[0]);

llvm/include/llvm/Demangle/ItaniumDemangle.h

   class SaveTemplateParams {
     AbstractManglingParser *Parser;
     decltype(TemplateParams) OldParams;
+    decltype(OuterTemplateParams) OldOuterParams;
 
   public:
     SaveTemplateParams(AbstractManglingParser *TheParser) : Parser(TheParser) {
       OldParams = std::move(Parser->TemplateParams);
+      OldOuterParams = std::move(Parser->OuterTemplateParams);
       Parser->TemplateParams.clear();
+      Parser->OuterTemplateParams.clear();
     }
     ~SaveTemplateParams() {
       Parser->TemplateParams = std::move(OldParams);
+      Parser->OuterTemplateParams = std::move(OldOuterParams);
     }
   } SaveTemplateParams(this);