search for: pointer_from_objref

...llaboration, or at least sharing insights and experiences! llvm.experimental.gc.ptrtoint: dropgcroot_type = FunctionType::get(PtrIntTy, makeArrayRef(PointerType::get(AddressSpace::Derived)), false); dropgcroot_func = Function::Create(dropgcroot_type, Function::ExternalLinkage, "julia.pointer_from_objref"); dropgcroot_func->addFnAttr(Attribute::ReadNone); dropgcroot_func->addFnAttr(Attribute::NoUnwind); declare void* @"julia.pointer_from_objref"(void addrspace(2)*) readnone unwind (AddressSpace::Derived in the signature means it doesn't need to be valid as a r...

Hi All, I'm working on a project converting Dart to llvm. Dart uses a relocating GC but additionally uses pointer tagging. The first bit of a pointer is a tag. For integers a '0' bit is used and for pointers to objects a '1' bit is used. V8 apparently uses a similar technique. Generated code may need to check which bit is used when this information isn't statically known.