Implement demangling support for C++20 lambda expression extensions.
This implements demangling support for the mangling extensions specified
in https://github.com/itanium-cxx-abi/cxx-abi/pull/85, much of which is
implemented in Clang r359967 and r371004.
Specifically, this provides demangling for:
* <template-param-decl> in <lambda-sig>
* <template-param> with non-zero level
* lambda-expression literals (not emitted by Clang yet)
* nullptr literals
* string literals
(The final two seem unrelated, but handling them was necessary in order
to disambiguate between lambda expressions and the other forms of
literal for which we have a type but no value.)
When demangling a <lambda-sig>, we form template parameters with no
corresponding argument, so we cannot substitute in the argument in the
demangling. Instead we invent synthetic names for the template
parameters (eg, '[]<typename $T>($T *x)').
git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@371273 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed
