| //! Handling of everything related to the calling convention. Also fills `fx.local_map`. |
| |
| mod comments; |
| mod pass_mode; |
| mod returning; |
| |
| use std::borrow::Cow; |
| |
| use cranelift_module::ModuleError; |
| use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags; |
| use rustc_middle::ty::layout::FnAbiOf; |
| use rustc_session::Session; |
| use rustc_target::abi::call::{Conv, FnAbi}; |
| use rustc_target::spec::abi::Abi; |
| |
| use cranelift_codegen::ir::{AbiParam, SigRef}; |
| |
| use self::pass_mode::*; |
| use crate::prelude::*; |
| |
| pub(crate) use self::returning::codegen_return; |
| |
| fn clif_sig_from_fn_abi<'tcx>( |
| tcx: TyCtxt<'tcx>, |
| default_call_conv: CallConv, |
| fn_abi: &FnAbi<'tcx, Ty<'tcx>>, |
| ) -> Signature { |
| let call_conv = conv_to_call_conv(tcx.sess, fn_abi.conv, default_call_conv); |
| |
| let inputs = fn_abi.args.iter().flat_map(|arg_abi| arg_abi.get_abi_param(tcx).into_iter()); |
| |
| let (return_ptr, returns) = fn_abi.ret.get_abi_return(tcx); |
| // Sometimes the first param is an pointer to the place where the return value needs to be stored. |
| let params: Vec<_> = return_ptr.into_iter().chain(inputs).collect(); |
| |
| Signature { params, returns, call_conv } |
| } |
| |
| pub(crate) fn conv_to_call_conv(sess: &Session, c: Conv, default_call_conv: CallConv) -> CallConv { |
| match c { |
| Conv::Rust | Conv::C => default_call_conv, |
| Conv::RustCold => CallConv::Cold, |
| Conv::X86_64SysV => CallConv::SystemV, |
| Conv::X86_64Win64 => CallConv::WindowsFastcall, |
| |
| // Should already get a back compat warning |
| Conv::X86Fastcall | Conv::X86Stdcall | Conv::X86ThisCall | Conv::X86VectorCall => { |
| default_call_conv |
| } |
| |
| Conv::X86Intr => sess.fatal("x86-interrupt call conv not yet implemented"), |
| |
| Conv::ArmAapcs => sess.fatal("aapcs call conv not yet implemented"), |
| Conv::CCmseNonSecureCall => { |
| sess.fatal("C-cmse-nonsecure-call call conv is not yet implemented"); |
| } |
| |
| Conv::Msp430Intr |
| | Conv::PtxKernel |
| | Conv::AmdGpuKernel |
| | Conv::AvrInterrupt |
| | Conv::AvrNonBlockingInterrupt => { |
| unreachable!("tried to use {c:?} call conv which only exists on an unsupported target"); |
| } |
| } |
| } |
| |
| pub(crate) fn get_function_sig<'tcx>( |
| tcx: TyCtxt<'tcx>, |
| default_call_conv: CallConv, |
| inst: Instance<'tcx>, |
| ) -> Signature { |
| assert!(!inst.substs.has_infer()); |
| clif_sig_from_fn_abi( |
| tcx, |
| default_call_conv, |
| &RevealAllLayoutCx(tcx).fn_abi_of_instance(inst, ty::List::empty()), |
| ) |
| } |
| |
| /// Instance must be monomorphized |
| pub(crate) fn import_function<'tcx>( |
| tcx: TyCtxt<'tcx>, |
| module: &mut dyn Module, |
| inst: Instance<'tcx>, |
| ) -> FuncId { |
| let name = tcx.symbol_name(inst).name; |
| let sig = get_function_sig(tcx, module.target_config().default_call_conv, inst); |
| match module.declare_function(name, Linkage::Import, &sig) { |
| Ok(func_id) => func_id, |
| Err(ModuleError::IncompatibleDeclaration(_)) => tcx.sess.fatal(format!( |
| "attempt to declare `{name}` as function, but it was already declared as static" |
| )), |
| Err(ModuleError::IncompatibleSignature(_, prev_sig, new_sig)) => tcx.sess.fatal(format!( |
| "attempt to declare `{name}` with signature {new_sig:?}, \ |
| but it was already declared with signature {prev_sig:?}" |
| )), |
| Err(err) => Err::<_, _>(err).unwrap(), |
| } |
| } |
| |
| impl<'tcx> FunctionCx<'_, '_, 'tcx> { |
| /// Instance must be monomorphized |
| pub(crate) fn get_function_ref(&mut self, inst: Instance<'tcx>) -> FuncRef { |
| let func_id = import_function(self.tcx, self.module, inst); |
| let func_ref = self.module.declare_func_in_func(func_id, &mut self.bcx.func); |
| |
| if self.clif_comments.enabled() { |
| self.add_comment(func_ref, format!("{:?}", inst)); |
| } |
| |
| func_ref |
| } |
| |
| pub(crate) fn lib_call( |
| &mut self, |
| name: &str, |
| params: Vec<AbiParam>, |
| returns: Vec<AbiParam>, |
| args: &[Value], |
| ) -> Cow<'_, [Value]> { |
| if self.tcx.sess.target.is_like_windows { |
| let (mut params, mut args): (Vec<_>, Vec<_>) = |
| params |
| .into_iter() |
| .zip(args) |
| .map(|(param, &arg)| { |
| if param.value_type == types::I128 { |
| let arg_ptr = Pointer::stack_slot(self.bcx.create_sized_stack_slot( |
| StackSlotData { kind: StackSlotKind::ExplicitSlot, size: 16 }, |
| )); |
| arg_ptr.store(self, arg, MemFlags::trusted()); |
| (AbiParam::new(self.pointer_type), arg_ptr.get_addr(self)) |
| } else { |
| (param, arg) |
| } |
| }) |
| .unzip(); |
| |
| let indirect_ret_val = returns.len() == 1 && returns[0].value_type == types::I128; |
| |
| if indirect_ret_val { |
| params.insert(0, AbiParam::new(self.pointer_type)); |
| let ret_ptr = |
| Pointer::stack_slot(self.bcx.create_sized_stack_slot(StackSlotData { |
| kind: StackSlotKind::ExplicitSlot, |
| size: 16, |
| })); |
| args.insert(0, ret_ptr.get_addr(self)); |
| self.lib_call_unadjusted(name, params, vec![], &args); |
| return Cow::Owned(vec![ret_ptr.load(self, types::I128, MemFlags::trusted())]); |
| } else { |
| return self.lib_call_unadjusted(name, params, returns, &args); |
| } |
| } |
| |
| self.lib_call_unadjusted(name, params, returns, args) |
| } |
| |
| pub(crate) fn lib_call_unadjusted( |
| &mut self, |
| name: &str, |
| params: Vec<AbiParam>, |
| returns: Vec<AbiParam>, |
| args: &[Value], |
| ) -> Cow<'_, [Value]> { |
| let sig = Signature { params, returns, call_conv: self.target_config.default_call_conv }; |
| let func_id = self.module.declare_function(name, Linkage::Import, &sig).unwrap(); |
| let func_ref = self.module.declare_func_in_func(func_id, &mut self.bcx.func); |
| if self.clif_comments.enabled() { |
| self.add_comment(func_ref, format!("{:?}", name)); |
| } |
| let call_inst = self.bcx.ins().call(func_ref, args); |
| if self.clif_comments.enabled() { |
| self.add_comment(call_inst, format!("lib_call {}", name)); |
| } |
| let results = self.bcx.inst_results(call_inst); |
| assert!(results.len() <= 2, "{}", results.len()); |
| Cow::Borrowed(results) |
| } |
| } |
| |
| /// Make a [`CPlace`] capable of holding value of the specified type. |
| fn make_local_place<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| local: Local, |
| layout: TyAndLayout<'tcx>, |
| is_ssa: bool, |
| ) -> CPlace<'tcx> { |
| if layout.is_unsized() { |
| fx.tcx.sess.span_fatal( |
| fx.mir.local_decls[local].source_info.span, |
| "unsized locals are not yet supported", |
| ); |
| } |
| let place = if is_ssa { |
| if let rustc_target::abi::Abi::ScalarPair(_, _) = layout.abi { |
| CPlace::new_var_pair(fx, local, layout) |
| } else { |
| CPlace::new_var(fx, local, layout) |
| } |
| } else { |
| CPlace::new_stack_slot(fx, layout) |
| }; |
| |
| self::comments::add_local_place_comments(fx, place, local); |
| |
| place |
| } |
| |
| pub(crate) fn codegen_fn_prelude<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, start_block: Block) { |
| fx.bcx.append_block_params_for_function_params(start_block); |
| |
| fx.bcx.switch_to_block(start_block); |
| fx.bcx.ins().nop(); |
| |
| let ssa_analyzed = crate::analyze::analyze(fx); |
| |
| self::comments::add_args_header_comment(fx); |
| |
| let mut block_params_iter = fx.bcx.func.dfg.block_params(start_block).to_vec().into_iter(); |
| let ret_place = |
| self::returning::codegen_return_param(fx, &ssa_analyzed, &mut block_params_iter); |
| assert_eq!(fx.local_map.push(ret_place), RETURN_PLACE); |
| |
| // None means pass_mode == NoPass |
| enum ArgKind<'tcx> { |
| Normal(Option<CValue<'tcx>>), |
| Spread(Vec<Option<CValue<'tcx>>>), |
| } |
| |
| let fn_abi = fx.fn_abi.take().unwrap(); |
| |
| // FIXME implement variadics in cranelift |
| if fn_abi.c_variadic { |
| fx.tcx.sess.span_fatal( |
| fx.mir.span, |
| "Defining variadic functions is not yet supported by Cranelift", |
| ); |
| } |
| |
| let mut arg_abis_iter = fn_abi.args.iter(); |
| |
| let func_params = fx |
| .mir |
| .args_iter() |
| .map(|local| { |
| let arg_ty = fx.monomorphize(fx.mir.local_decls[local].ty); |
| |
| // Adapted from https://github.com/rust-lang/rust/blob/145155dc96757002c7b2e9de8489416e2fdbbd57/src/librustc_codegen_llvm/mir/mod.rs#L442-L482 |
| if Some(local) == fx.mir.spread_arg { |
| // This argument (e.g. the last argument in the "rust-call" ABI) |
| // is a tuple that was spread at the ABI level and now we have |
| // to reconstruct it into a tuple local variable, from multiple |
| // individual function arguments. |
| |
| let tupled_arg_tys = match arg_ty.kind() { |
| ty::Tuple(ref tys) => tys, |
| _ => bug!("spread argument isn't a tuple?! but {:?}", arg_ty), |
| }; |
| |
| let mut params = Vec::new(); |
| for (i, _arg_ty) in tupled_arg_tys.iter().enumerate() { |
| let arg_abi = arg_abis_iter.next().unwrap(); |
| let param = |
| cvalue_for_param(fx, Some(local), Some(i), arg_abi, &mut block_params_iter); |
| params.push(param); |
| } |
| |
| (local, ArgKind::Spread(params), arg_ty) |
| } else { |
| let arg_abi = arg_abis_iter.next().unwrap(); |
| let param = |
| cvalue_for_param(fx, Some(local), None, arg_abi, &mut block_params_iter); |
| (local, ArgKind::Normal(param), arg_ty) |
| } |
| }) |
| .collect::<Vec<(Local, ArgKind<'tcx>, Ty<'tcx>)>>(); |
| |
| assert!(fx.caller_location.is_none()); |
| if fx.instance.def.requires_caller_location(fx.tcx) { |
| // Store caller location for `#[track_caller]`. |
| let arg_abi = arg_abis_iter.next().unwrap(); |
| fx.caller_location = |
| Some(cvalue_for_param(fx, None, None, arg_abi, &mut block_params_iter).unwrap()); |
| } |
| |
| assert!(arg_abis_iter.next().is_none(), "ArgAbi left behind"); |
| fx.fn_abi = Some(fn_abi); |
| assert!(block_params_iter.next().is_none(), "arg_value left behind"); |
| |
| self::comments::add_locals_header_comment(fx); |
| |
| for (local, arg_kind, ty) in func_params { |
| // While this is normally an optimization to prevent an unnecessary copy when an argument is |
| // not mutated by the current function, this is necessary to support unsized arguments. |
| if let ArgKind::Normal(Some(val)) = arg_kind { |
| if let Some((addr, meta)) = val.try_to_ptr() { |
| // Ownership of the value at the backing storage for an argument is passed to the |
| // callee per the ABI, so it is fine to borrow the backing storage of this argument |
| // to prevent a copy. |
| |
| let place = if let Some(meta) = meta { |
| CPlace::for_ptr_with_extra(addr, meta, val.layout()) |
| } else { |
| CPlace::for_ptr(addr, val.layout()) |
| }; |
| |
| self::comments::add_local_place_comments(fx, place, local); |
| |
| assert_eq!(fx.local_map.push(place), local); |
| continue; |
| } |
| } |
| |
| let layout = fx.layout_of(ty); |
| let is_ssa = ssa_analyzed[local].is_ssa(fx, ty); |
| let place = make_local_place(fx, local, layout, is_ssa); |
| assert_eq!(fx.local_map.push(place), local); |
| |
| match arg_kind { |
| ArgKind::Normal(param) => { |
| if let Some(param) = param { |
| place.write_cvalue(fx, param); |
| } |
| } |
| ArgKind::Spread(params) => { |
| for (i, param) in params.into_iter().enumerate() { |
| if let Some(param) = param { |
| place.place_field(fx, FieldIdx::new(i)).write_cvalue(fx, param); |
| } |
| } |
| } |
| } |
| } |
| |
| for local in fx.mir.vars_and_temps_iter() { |
| let ty = fx.monomorphize(fx.mir.local_decls[local].ty); |
| let layout = fx.layout_of(ty); |
| |
| let is_ssa = ssa_analyzed[local].is_ssa(fx, ty); |
| |
| let place = make_local_place(fx, local, layout, is_ssa); |
| assert_eq!(fx.local_map.push(place), local); |
| } |
| |
| fx.bcx.ins().jump(*fx.block_map.get(START_BLOCK).unwrap(), &[]); |
| } |
| |
| struct CallArgument<'tcx> { |
| value: CValue<'tcx>, |
| is_owned: bool, |
| } |
| |
| // FIXME avoid intermediate `CValue` before calling `adjust_arg_for_abi` |
| fn codegen_call_argument_operand<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| operand: &Operand<'tcx>, |
| ) -> CallArgument<'tcx> { |
| CallArgument { |
| value: codegen_operand(fx, operand), |
| is_owned: matches!(operand, Operand::Move(_)), |
| } |
| } |
| |
| pub(crate) fn codegen_terminator_call<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| source_info: mir::SourceInfo, |
| func: &Operand<'tcx>, |
| args: &[Operand<'tcx>], |
| destination: Place<'tcx>, |
| target: Option<BasicBlock>, |
| ) { |
| let func = codegen_operand(fx, func); |
| let fn_sig = func.layout().ty.fn_sig(fx.tcx); |
| |
| let ret_place = codegen_place(fx, destination); |
| |
| // Handle special calls like intrinsics and empty drop glue. |
| let instance = if let ty::FnDef(def_id, substs) = *func.layout().ty.kind() { |
| let instance = |
| ty::Instance::expect_resolve(fx.tcx, ty::ParamEnv::reveal_all(), def_id, substs) |
| .polymorphize(fx.tcx); |
| |
| if fx.tcx.symbol_name(instance).name.starts_with("llvm.") { |
| crate::intrinsics::codegen_llvm_intrinsic_call( |
| fx, |
| &fx.tcx.symbol_name(instance).name, |
| substs, |
| args, |
| ret_place, |
| target, |
| ); |
| return; |
| } |
| |
| match instance.def { |
| InstanceDef::Intrinsic(_) => { |
| crate::intrinsics::codegen_intrinsic_call( |
| fx, |
| instance, |
| args, |
| ret_place, |
| target, |
| source_info, |
| ); |
| return; |
| } |
| InstanceDef::DropGlue(_, None) => { |
| // empty drop glue - a nop. |
| let dest = target.expect("Non terminating drop_in_place_real???"); |
| let ret_block = fx.get_block(dest); |
| fx.bcx.ins().jump(ret_block, &[]); |
| return; |
| } |
| _ => Some(instance), |
| } |
| } else { |
| None |
| }; |
| |
| let extra_args = &args[fn_sig.inputs().skip_binder().len()..]; |
| let extra_args = fx.tcx.mk_type_list_from_iter( |
| extra_args.iter().map(|op_arg| fx.monomorphize(op_arg.ty(fx.mir, fx.tcx))), |
| ); |
| let fn_abi = if let Some(instance) = instance { |
| RevealAllLayoutCx(fx.tcx).fn_abi_of_instance(instance, extra_args) |
| } else { |
| RevealAllLayoutCx(fx.tcx).fn_abi_of_fn_ptr(fn_sig, extra_args) |
| }; |
| |
| let is_cold = if fn_sig.abi() == Abi::RustCold { |
| true |
| } else { |
| instance.is_some_and(|inst| { |
| fx.tcx.codegen_fn_attrs(inst.def_id()).flags.contains(CodegenFnAttrFlags::COLD) |
| }) |
| }; |
| if is_cold { |
| fx.bcx.set_cold_block(fx.bcx.current_block().unwrap()); |
| if let Some(destination_block) = target { |
| fx.bcx.set_cold_block(fx.get_block(destination_block)); |
| } |
| } |
| |
| // Unpack arguments tuple for closures |
| let mut args = if fn_sig.abi() == Abi::RustCall { |
| assert_eq!(args.len(), 2, "rust-call abi requires two arguments"); |
| let self_arg = codegen_call_argument_operand(fx, &args[0]); |
| let pack_arg = codegen_call_argument_operand(fx, &args[1]); |
| |
| let tupled_arguments = match pack_arg.value.layout().ty.kind() { |
| ty::Tuple(ref tupled_arguments) => tupled_arguments, |
| _ => bug!("argument to function with \"rust-call\" ABI is not a tuple"), |
| }; |
| |
| let mut args = Vec::with_capacity(1 + tupled_arguments.len()); |
| args.push(self_arg); |
| for i in 0..tupled_arguments.len() { |
| args.push(CallArgument { |
| value: pack_arg.value.value_field(fx, FieldIdx::new(i)), |
| is_owned: pack_arg.is_owned, |
| }); |
| } |
| args |
| } else { |
| args.iter().map(|arg| codegen_call_argument_operand(fx, arg)).collect::<Vec<_>>() |
| }; |
| |
| // Pass the caller location for `#[track_caller]`. |
| if instance.is_some_and(|inst| inst.def.requires_caller_location(fx.tcx)) { |
| let caller_location = fx.get_caller_location(source_info); |
| args.push(CallArgument { value: caller_location, is_owned: false }); |
| } |
| |
| let args = args; |
| assert_eq!(fn_abi.args.len(), args.len()); |
| |
| enum CallTarget { |
| Direct(FuncRef), |
| Indirect(SigRef, Value), |
| } |
| |
| let (func_ref, first_arg_override) = match instance { |
| // Trait object call |
| Some(Instance { def: InstanceDef::Virtual(_, idx), .. }) => { |
| if fx.clif_comments.enabled() { |
| let nop_inst = fx.bcx.ins().nop(); |
| fx.add_comment( |
| nop_inst, |
| format!("virtual call; self arg pass mode: {:?}", &fn_abi.args[0]), |
| ); |
| } |
| |
| let (ptr, method) = crate::vtable::get_ptr_and_method_ref(fx, args[0].value, idx); |
| let sig = clif_sig_from_fn_abi(fx.tcx, fx.target_config.default_call_conv, &fn_abi); |
| let sig = fx.bcx.import_signature(sig); |
| |
| (CallTarget::Indirect(sig, method), Some(ptr.get_addr(fx))) |
| } |
| |
| // Normal call |
| Some(instance) => { |
| let func_ref = fx.get_function_ref(instance); |
| (CallTarget::Direct(func_ref), None) |
| } |
| |
| // Indirect call |
| None => { |
| if fx.clif_comments.enabled() { |
| let nop_inst = fx.bcx.ins().nop(); |
| fx.add_comment(nop_inst, "indirect call"); |
| } |
| |
| let func = func.load_scalar(fx); |
| let sig = clif_sig_from_fn_abi(fx.tcx, fx.target_config.default_call_conv, &fn_abi); |
| let sig = fx.bcx.import_signature(sig); |
| |
| (CallTarget::Indirect(sig, func), None) |
| } |
| }; |
| |
| self::returning::codegen_with_call_return_arg(fx, &fn_abi.ret, ret_place, |fx, return_ptr| { |
| let call_args = return_ptr |
| .into_iter() |
| .chain(first_arg_override.into_iter()) |
| .chain( |
| args.into_iter() |
| .enumerate() |
| .skip(if first_arg_override.is_some() { 1 } else { 0 }) |
| .flat_map(|(i, arg)| { |
| adjust_arg_for_abi(fx, arg.value, &fn_abi.args[i], arg.is_owned).into_iter() |
| }), |
| ) |
| .collect::<Vec<Value>>(); |
| |
| let call_inst = match func_ref { |
| CallTarget::Direct(func_ref) => fx.bcx.ins().call(func_ref, &call_args), |
| CallTarget::Indirect(sig, func_ptr) => { |
| fx.bcx.ins().call_indirect(sig, func_ptr, &call_args) |
| } |
| }; |
| |
| // FIXME find a cleaner way to support varargs |
| if fn_sig.c_variadic() { |
| if !matches!(fn_sig.abi(), Abi::C { .. }) { |
| fx.tcx.sess.span_fatal( |
| source_info.span, |
| format!("Variadic call for non-C abi {:?}", fn_sig.abi()), |
| ); |
| } |
| let sig_ref = fx.bcx.func.dfg.call_signature(call_inst).unwrap(); |
| let abi_params = call_args |
| .into_iter() |
| .map(|arg| { |
| let ty = fx.bcx.func.dfg.value_type(arg); |
| if !ty.is_int() { |
| // FIXME set %al to upperbound on float args once floats are supported |
| fx.tcx.sess.span_fatal( |
| source_info.span, |
| format!("Non int ty {:?} for variadic call", ty), |
| ); |
| } |
| AbiParam::new(ty) |
| }) |
| .collect::<Vec<AbiParam>>(); |
| fx.bcx.func.dfg.signatures[sig_ref].params = abi_params; |
| } |
| |
| call_inst |
| }); |
| |
| if let Some(dest) = target { |
| let ret_block = fx.get_block(dest); |
| fx.bcx.ins().jump(ret_block, &[]); |
| } else { |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| } |
| } |
| |
| pub(crate) fn codegen_drop<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| source_info: mir::SourceInfo, |
| drop_place: CPlace<'tcx>, |
| ) { |
| let ty = drop_place.layout().ty; |
| let drop_instance = Instance::resolve_drop_in_place(fx.tcx, ty).polymorphize(fx.tcx); |
| |
| if let ty::InstanceDef::DropGlue(_, None) = drop_instance.def { |
| // we don't actually need to drop anything |
| } else { |
| match ty.kind() { |
| 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 (ptr, vtable) = drop_place.to_ptr_unsized(); |
| let ptr = ptr.get_addr(fx); |
| let drop_fn = crate::vtable::drop_fn_of_obj(fx, vtable); |
| |
| // FIXME(eddyb) perhaps move some of this logic into |
| // `Instance::resolve_drop_in_place`? |
| let virtual_drop = Instance { |
| def: ty::InstanceDef::Virtual(drop_instance.def_id(), 0), |
| substs: drop_instance.substs, |
| }; |
| let fn_abi = |
| RevealAllLayoutCx(fx.tcx).fn_abi_of_instance(virtual_drop, ty::List::empty()); |
| |
| let sig = clif_sig_from_fn_abi(fx.tcx, fx.target_config.default_call_conv, &fn_abi); |
| let sig = fx.bcx.import_signature(sig); |
| fx.bcx.ins().call_indirect(sig, drop_fn, &[ptr]); |
| } |
| 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 (data, vtable) = drop_place.to_cvalue(fx).dyn_star_force_data_on_stack(fx); |
| let drop_fn = crate::vtable::drop_fn_of_obj(fx, vtable); |
| |
| let virtual_drop = Instance { |
| def: ty::InstanceDef::Virtual(drop_instance.def_id(), 0), |
| substs: drop_instance.substs, |
| }; |
| let fn_abi = |
| RevealAllLayoutCx(fx.tcx).fn_abi_of_instance(virtual_drop, ty::List::empty()); |
| |
| let sig = clif_sig_from_fn_abi(fx.tcx, fx.target_config.default_call_conv, &fn_abi); |
| let sig = fx.bcx.import_signature(sig); |
| fx.bcx.ins().call_indirect(sig, drop_fn, &[data]); |
| } |
| _ => { |
| assert!(!matches!(drop_instance.def, InstanceDef::Virtual(_, _))); |
| |
| let fn_abi = |
| RevealAllLayoutCx(fx.tcx).fn_abi_of_instance(drop_instance, ty::List::empty()); |
| |
| let arg_value = drop_place.place_ref( |
| fx, |
| fx.layout_of(fx.tcx.mk_ref( |
| fx.tcx.lifetimes.re_erased, |
| TypeAndMut { ty, mutbl: crate::rustc_hir::Mutability::Mut }, |
| )), |
| ); |
| let arg_value = adjust_arg_for_abi(fx, arg_value, &fn_abi.args[0], true); |
| |
| let mut call_args: Vec<Value> = arg_value.into_iter().collect::<Vec<_>>(); |
| |
| if drop_instance.def.requires_caller_location(fx.tcx) { |
| // Pass the caller location for `#[track_caller]`. |
| let caller_location = fx.get_caller_location(source_info); |
| call_args.extend( |
| adjust_arg_for_abi(fx, caller_location, &fn_abi.args[1], false).into_iter(), |
| ); |
| } |
| |
| let func_ref = fx.get_function_ref(drop_instance); |
| fx.bcx.ins().call(func_ref, &call_args); |
| } |
| } |
| } |
| } |
