[libcxx-commits] [libcxxabi] b03f175 - [demangler] More properly save and restore the template parameter state

[Richard Smith via libcxx-commits]

Author: Richard Smith
Date: 2020-07-09T21:12:51-07:00
New Revision: b03f1756fb4fd5ac5d606a7e4fd8aea1d9f18541

URL: https://github.com/llvm/llvm-project/commit/b03f1756fb4fd5ac5d606a7e4fd8aea1d9f18541
DIFF: https://github.com/llvm/llvm-project/commit/b03f1756fb4fd5ac5d606a7e4fd8aea1d9f18541.diff

LOG: [demangler] More properly save and restore the template parameter state
when parsing an encoding.

Added: 
    

Modified: 
    libcxxabi/src/demangle/ItaniumDemangle.h
    libcxxabi/test/test_demangle.pass.cpp
    llvm/include/llvm/Demangle/ItaniumDemangle.h

Removed: 
    


################################################################################
diff  --git a/libcxxabi/src/demangle/ItaniumDemangle.h b/libcxxabi/src/demangle/ItaniumDemangle.h
index 0f81675f244d..6ab873218386 100644
--- a/libcxxabi/src/demangle/ItaniumDemangle.h
+++ b/libcxxabi/src/demangle/ItaniumDemangle.h
@@ -5096,7 +5096,21 @@ Node *AbstractManglingParser<Derived, Alloc>::parseSpecialName() {
 //            ::= <special-name>
 template <typename Derived, typename Alloc>
 Node *AbstractManglingParser<Derived, Alloc>::parseEncoding() {
-  ScopedTemplateParamList EncodingTemplateParams(this);
+  // The template parameters of an encoding are unrelated to those of the
+  // enclosing context.
+  class SaveTemplateParams {
+    AbstractManglingParser *Parser;
+    decltype(TemplateParams) OldParams;
+
+  public:
+    SaveTemplateParams(AbstractManglingParser *Parser) : Parser(Parser) {
+      OldParams = std::move(Parser->TemplateParams);
+      Parser->TemplateParams.clear();
+    }
+    ~SaveTemplateParams() {
+      Parser->TemplateParams = std::move(OldParams);
+    }
+  } SaveTemplateParams(this);
 
   if (look() == 'G' || look() == 'T')
     return getDerived().parseSpecialName();

diff  --git a/libcxxabi/test/test_demangle.pass.cpp b/libcxxabi/test/test_demangle.pass.cpp
index b8b2ad51a994..ef75b61a94af 100644
--- a/libcxxabi/test/test_demangle.pass.cpp
+++ b/libcxxabi/test/test_demangle.pass.cpp
@@ -29796,6 +29796,7 @@ const char* cases[][2] =
     // FIXME: This is wrong, should demangle to the same as the previous entry.
     // See https://github.com/itanium-cxx-abi/cxx-abi/issues/106.
     {"_ZN1XIZ1fIiEvOT_EUlS2_DpT0_E_EclIJEEEvDpT_", "void X<void f<int>(int&&)::'lambda'(int&&, auto...)>::operator()<>()"},
+    {"_ZZZZN6abcdef9abcdefghi29abcdefabcdefabcdefabcefabcdef27xxxxxxxxxxxxxxxxxxxxxxxxxxxEN4absl8DurationERKNSt3__u12basic_stringIcNS4_11char_traitsIcEENS4_9allocatorIcEEEEPNS1_19yyyyyyyyyyyyyyyyyyyEENK3$_5clEvENKUlvE_clEvE6zzzzzz", "abcdef::abcdefghi::abcdefabcdefabcdefabcefabcdef::xxxxxxxxxxxxxxxxxxxxxxxxxxx(absl::Duration, std::__u::basic_string<char, std::__u::char_traits<char>, std::__u::allocator<char> > const&, abcdef::abcdefghi::abcdefabcdefabcdefabcefabcdef::yyyyyyyyyyyyyyyyyyy*)::$_5::operator()() const::'lambda'()::operator()() const::zzzzzz"},
 
     // FIXME: This is wrong; the S2_ backref should expand to OT_ and then to
     // "double&&". But we can't cope with a substitution that represents a

diff  --git a/llvm/include/llvm/Demangle/ItaniumDemangle.h b/llvm/include/llvm/Demangle/ItaniumDemangle.h
index 0f81675f244d..6ab873218386 100644
--- a/llvm/include/llvm/Demangle/ItaniumDemangle.h
+++ b/llvm/include/llvm/Demangle/ItaniumDemangle.h
@@ -5096,7 +5096,21 @@ Node *AbstractManglingParser<Derived, Alloc>::parseSpecialName() {
 //            ::= <special-name>
 template <typename Derived, typename Alloc>
 Node *AbstractManglingParser<Derived, Alloc>::parseEncoding() {
-  ScopedTemplateParamList EncodingTemplateParams(this);
+  // The template parameters of an encoding are unrelated to those of the
+  // enclosing context.
+  class SaveTemplateParams {
+    AbstractManglingParser *Parser;
+    decltype(TemplateParams) OldParams;
+
+  public:
+    SaveTemplateParams(AbstractManglingParser *Parser) : Parser(Parser) {
+      OldParams = std::move(Parser->TemplateParams);
+      Parser->TemplateParams.clear();
+    }
+    ~SaveTemplateParams() {
+      Parser->TemplateParams = std::move(OldParams);
+    }
+  } SaveTemplateParams(this);
 
   if (look() == 'G' || look() == 'T')
     return getDerived().parseSpecialName();