diff options
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/mir/block.rs | 158 |
1 files changed, 78 insertions, 80 deletions
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs index 9af408646ae..daaa4de1a7c 100644 --- a/compiler/rustc_codegen_ssa/src/mir/block.rs +++ b/compiler/rustc_codegen_ssa/src/mir/block.rs @@ -452,86 +452,84 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { args1 = [place.llval]; &args1[..] }; - let (drop_fn, fn_abi) = match ty.kind() { - // FIXME(eddyb) perhaps move some of this logic into - // `Instance::resolve_drop_in_place`? - ty::Dynamic(_, _, ty::Dyn) => { - // IN THIS ARM, WE HAVE: - // ty = *mut (dyn Trait) - // which is: exists<T> ( *mut T, Vtable<T: Trait> ) - // args[0] args[1] - // - // args = ( Data, Vtable ) - // | - // v - // /-------\ - // | ... | - // \-------/ - // - let virtual_drop = Instance { - def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), - substs: drop_fn.substs, - }; - debug!("ty = {:?}", ty); - debug!("drop_fn = {:?}", drop_fn); - debug!("args = {:?}", args); - let fn_abi = bx.fn_abi_of_instance(virtual_drop, ty::List::empty()); - let vtable = args[1]; - // Truncate vtable off of args list - args = &args[..1]; - ( - meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_DROPINPLACE) - .get_fn(bx, vtable, ty, &fn_abi), - fn_abi, - ) - } - ty::Dynamic(_, _, ty::DynStar) => { - // IN THIS ARM, WE HAVE: - // ty = *mut (dyn* Trait) - // which is: *mut exists<T: sizeof(T) == sizeof(usize)> (T, Vtable<T: Trait>) - // - // args = [ * ] - // | - // v - // ( Data, Vtable ) - // | - // v - // /-------\ - // | ... | - // \-------/ - // - // - // WE CAN CONVERT THIS INTO THE ABOVE LOGIC BY DOING - // - // data = &(*args[0]).0 // gives a pointer to Data above (really the same pointer) - // vtable = (*args[0]).1 // loads the vtable out - // (data, vtable) // an equivalent Rust `*mut dyn Trait` - // - // SO THEN WE CAN USE THE ABOVE CODE. - let virtual_drop = Instance { - def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), - substs: drop_fn.substs, - }; - debug!("ty = {:?}", ty); - debug!("drop_fn = {:?}", drop_fn); - debug!("args = {:?}", args); - let fn_abi = bx.fn_abi_of_instance(virtual_drop, ty::List::empty()); - let data = args[0]; - let data_ty = bx.cx().backend_type(place.layout); - let vtable_ptr = - bx.gep(data_ty, data, &[bx.cx().const_i32(0), bx.cx().const_i32(1)]); - let vtable = bx.load(bx.type_i8p(), vtable_ptr, abi::Align::ONE); - // Truncate vtable off of args list - args = &args[..1]; - debug!("args' = {:?}", args); - ( - meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_DROPINPLACE) - .get_fn(bx, vtable, ty, &fn_abi), - fn_abi, - ) - } - _ => (bx.get_fn_addr(drop_fn), bx.fn_abi_of_instance(drop_fn, ty::List::empty())), - }; + let (drop_fn, fn_abi) = + match ty.kind() { + // FIXME(eddyb) perhaps move some of this logic into + // `Instance::resolve_drop_in_place`? + ty::Dynamic(_, _, ty::Dyn) => { + // IN THIS ARM, WE HAVE: + // ty = *mut (dyn Trait) + // which is: exists<T> ( *mut T, Vtable<T: Trait> ) + // args[0] args[1] + // + // args = ( Data, Vtable ) + // | + // v + // /-------\ + // | ... | + // \-------/ + // + let virtual_drop = Instance { + def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), + substs: drop_fn.substs, + }; + debug!("ty = {:?}", ty); + debug!("drop_fn = {:?}", drop_fn); + debug!("args = {:?}", args); + let fn_abi = bx.fn_abi_of_instance(virtual_drop, ty::List::empty()); + let vtable = args[1]; + // Truncate vtable off of args list + args = &args[..1]; + ( + meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_DROPINPLACE) + .get_fn(bx, vtable, ty, &fn_abi), + fn_abi, + ) + } + ty::Dynamic(_, _, ty::DynStar) => { + // IN THIS ARM, WE HAVE: + // ty = *mut (dyn* Trait) + // which is: *mut exists<T: sizeof(T) == sizeof(usize)> (T, Vtable<T: Trait>) + // + // args = [ * ] + // | + // v + // ( Data, Vtable ) + // | + // v + // /-------\ + // | ... | + // \-------/ + // + // + // WE CAN CONVERT THIS INTO THE ABOVE LOGIC BY DOING + // + // data = &(*args[0]).0 // gives a pointer to Data above (really the same pointer) + // vtable = (*args[0]).1 // loads the vtable out + // (data, vtable) // an equivalent Rust `*mut dyn Trait` + // + // SO THEN WE CAN USE THE ABOVE CODE. + let virtual_drop = Instance { + def: ty::InstanceDef::Virtual(drop_fn.def_id(), 0), + substs: drop_fn.substs, + }; + debug!("ty = {:?}", ty); + debug!("drop_fn = {:?}", drop_fn); + debug!("args = {:?}", args); + let fn_abi = bx.fn_abi_of_instance(virtual_drop, ty::List::empty()); + let meta_ptr = place.project_field(bx, 1); + let meta = bx.load_operand(meta_ptr); + // Truncate vtable off of args list + args = &args[..1]; + debug!("args' = {:?}", args); + ( + meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_DROPINPLACE) + .get_fn(bx, meta.immediate(), ty, &fn_abi), + fn_abi, + ) + } + _ => (bx.get_fn_addr(drop_fn), bx.fn_abi_of_instance(drop_fn, ty::List::empty())), + }; helper.do_call( self, bx, |