[PATCH] D44415: [PM][FunctionAttrs] add NoUnwind attribute inference to PostOrderFunctionAttrs pass

[Justin Lebar via Phabricator via llvm-commits]

jlebar added a comment.

> generating direct calls here seems really, really hard... Maybe you have an idea I don't see...

It's...not awful.  https://godbolt.org/g/D3KMQH

  #include <array>
  #include <vector>
  #include <utility>
  
  struct Instruction;
  
  struct FooDescriptor {
    static bool IsGood(Instruction* I) { return true; }
  };
  
  struct BarDescriptor {
    static bool IsGood(Instruction* I) { return false; }
  };
  
  template <typename... Descriptors>
  struct AttrInferer {
      void Foo(std::vector<Instruction*> Instrs) {
          for (Instruction* Instr : Instrs) {
              bool IsGood[] = {
                  [&] { return Descriptors::IsGood(Instr); }()...
              };
              for (int i = 0; i < sizeof...(Descriptors); ++i) {
                  
              }
          }
      }
  };
  
  void Test() {
      AttrInferer<FooDescriptor, BarDescriptor> a;
      a.Foo({});
  }

Anyway if you think the virtual functions aren't a big deal, that's good enough for me.


Repository:
  rL LLVM

https://reviews.llvm.org/D44415