src/abi.rs

   1 use std::iter;
   2
   3 use rustc::hir;
   4 use rustc_target::spec::abi::Abi;
   5
   6 use crate::prelude::*;
   7
   8 #[derive(Debug)]
   9 enum PassMode {
  10     NoPass,
  11     ByVal(Type),
  12     ByRef,
  13 }
  14
  15 impl PassMode {
  16     fn get_param_ty(self, _fx: &FunctionCx) -> Type {
  17         match self {
  18             PassMode::NoPass => unimplemented!("pass mode nopass"),
  19             PassMode::ByVal(cton_type) => cton_type,
  20             PassMode::ByRef => types::I64,
  21         }
  22     }
  23 }
  24
  25 fn get_pass_mode<'a, 'tcx: 'a>(
  26     tcx: TyCtxt<'a, 'tcx, 'tcx>,
  27     abi: Abi,
  28     ty: Ty<'tcx>,
  29     is_return: bool,
  30 ) -> PassMode {
  31     if ty.sty == tcx.mk_nil().sty {
  32         if is_return {
  33             //if false {
  34             PassMode::NoPass
  35         } else {
  36             PassMode::ByRef
  37         }
  38     } else if let Some(ret_ty) = crate::common::cton_type_from_ty(tcx, ty) {
  39         PassMode::ByVal(ret_ty)
  40     } else {
  41         if abi == Abi::C {
  42             unimplemented!("Non scalars are not yet supported for \"C\" abi");
  43         }
  44         PassMode::ByRef
  45     }
  46 }
  47
  48 pub fn cton_sig_from_fn_ty<'a, 'tcx: 'a>(
  49     tcx: TyCtxt<'a, 'tcx, 'tcx>,
  50     fn_ty: Ty<'tcx>,
  51 ) -> Signature {
  52     let sig = ty_fn_sig(tcx, fn_ty);
  53     assert!(!sig.variadic, "Variadic function are not yet supported");
  54     let (call_conv, inputs, output): (CallConv, Vec<Ty>, Ty) = match sig.abi {
  55         Abi::Rust => (CallConv::Fast, sig.inputs().to_vec(), sig.output()),
  56         Abi::C => (CallConv::SystemV, sig.inputs().to_vec(), sig.output()),
  57         Abi::RustCall => {
  58             println!(
  59                 "rust-call sig: {:?} inputs: {:?} output: {:?}",
  60                 sig,
  61                 sig.inputs(),
  62                 sig.output()
  63             );
  64             assert_eq!(sig.inputs().len(), 2);
  65             let extra_args = match sig.inputs().last().unwrap().sty {
  66                 ty::TyTuple(ref tupled_arguments) => tupled_arguments,
  67                 _ => bug!("argument to function with \"rust-call\" ABI is not a tuple"),
  68             };
  69             let mut inputs: Vec<Ty> = vec![sig.inputs()[0]];
  70             inputs.extend(extra_args.into_iter());
  71             (CallConv::Fast, inputs, sig.output())
  72         }
  73         Abi::System => bug!("system abi should be selected elsewhere"),
  74         Abi::RustIntrinsic => (CallConv::SystemV, sig.inputs().to_vec(), sig.output()),
  75         _ => unimplemented!("unsupported abi {:?}", sig.abi),
  76     };
  77
  78     let inputs = inputs
  79         .into_iter()
  80         .filter_map(|ty| match get_pass_mode(tcx, sig.abi, ty, false) {
  81             PassMode::ByVal(cton_ty) => Some(cton_ty),
  82             PassMode::NoPass => unimplemented!("pass mode nopass"),
  83             PassMode::ByRef => Some(types::I64),
  84         });
  85
  86     let (params, returns) = match get_pass_mode(tcx, sig.abi, output, true) {
  87         PassMode::NoPass => (inputs.map(AbiParam::new).collect(), vec![]),
  88         PassMode::ByVal(ret_ty) => (
  89             inputs.map(AbiParam::new).collect(),
  90             vec![AbiParam::new(ret_ty)],
  91         ),
  92         PassMode::ByRef => {
  93             (
  94                 Some(types::I64).into_iter() // First param is place to put return val
  95                     .chain(inputs)
  96                     .map(AbiParam::new)
  97                     .collect(),
  98                 vec![],
  99             )
 100         }
 101     };
 102
 103     Signature {
 104         params,
 105         returns,
 106         call_conv,
 107         argument_bytes: None,
 108     }
 109 }
 110
 111 fn ty_fn_sig<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, ty: Ty<'tcx>) -> ty::FnSig<'tcx> {
 112     let sig = match ty.sty {
 113         ty::TyFnDef(..) |
 114         // Shims currently have type TyFnPtr. Not sure this should remain.
 115         ty::TyFnPtr(_) => ty.fn_sig(tcx),
 116         ty::TyClosure(def_id, substs) => {
 117             let sig = substs.closure_sig(def_id, tcx);
 118
 119             let env_ty = tcx.closure_env_ty(def_id, substs).unwrap();
 120             sig.map_bound(|sig| tcx.mk_fn_sig(
 121                 iter::once(*env_ty.skip_binder()).chain(sig.inputs().iter().cloned()),
 122                 sig.output(),
 123                 sig.variadic,
 124                 sig.unsafety,
 125                 sig.abi
 126             ))
 127         }
 128         ty::TyGenerator(def_id, substs, _) => {
 129             let sig = substs.poly_sig(def_id, tcx);
 130
 131             let env_region = ty::ReLateBound(ty::INNERMOST, ty::BrEnv);
 132             let env_ty = tcx.mk_mut_ref(tcx.mk_region(env_region), ty);
 133
 134             sig.map_bound(|sig| {
 135                 let state_did = tcx.lang_items().gen_state().unwrap();
 136                 let state_adt_ref = tcx.adt_def(state_did);
 137                 let state_substs = tcx.intern_substs(&[
 138                     sig.yield_ty.into(),
 139                     sig.return_ty.into(),
 140                 ]);
 141                 let ret_ty = tcx.mk_adt(state_adt_ref, state_substs);
 142
 143                 tcx.mk_fn_sig(iter::once(env_ty),
 144                     ret_ty,
 145                     false,
 146                     hir::Unsafety::Normal,
 147                     Abi::Rust
 148                 )
 149             })
 150         }
 151         _ => bug!("unexpected type {:?} to ty_fn_sig", ty)
 152     };
 153     tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), &sig)
 154 }
 155
 156 pub fn get_function_name_and_sig<'a, 'tcx>(
 157     tcx: TyCtxt<'a, 'tcx, 'tcx>,
 158     inst: Instance<'tcx>,
 159 ) -> (String, Signature) {
 160     assert!(!inst.substs.needs_infer() && !inst.substs.has_param_types());
 161     let fn_ty = inst.ty(tcx);
 162     let sig = cton_sig_from_fn_ty(tcx, fn_ty);
 163     (tcx.symbol_name(inst).as_str().to_string(), sig)
 164 }
 165
 166 impl<'a, 'tcx: 'a> FunctionCx<'a, 'tcx> {
 167     /// Instance must be monomorphized
 168     pub fn get_function_ref(&mut self, inst: Instance<'tcx>) -> FuncRef {
 169         let (name, sig) = get_function_name_and_sig(self.tcx, inst);
 170         let func_id = self
 171             .module
 172             .declare_function(&name, Linkage::Import, &sig)
 173             .unwrap();
 174         self.module
 175             .declare_func_in_func(func_id, &mut self.bcx.func)
 176     }
 177
 178     fn lib_call(
 179         &mut self,
 180         name: &str,
 181         input_tys: Vec<types::Type>,
 182         output_ty: Option<types::Type>,
 183         args: &[Value],
 184     ) -> Option<Value> {
 185         let sig = Signature {
 186             params: input_tys.iter().cloned().map(AbiParam::new).collect(),
 187             returns: vec![AbiParam::new(output_ty.unwrap_or(types::VOID))],
 188             call_conv: CallConv::SystemV,
 189             argument_bytes: None,
 190         };
 191         let func_id = self
 192             .module
 193             .declare_function(&name, Linkage::Import, &sig)
 194             .unwrap();
 195         let func_ref = self
 196             .module
 197             .declare_func_in_func(func_id, &mut self.bcx.func);
 198         let call_inst = self.bcx.ins().call(func_ref, args);
 199         if output_ty.is_none() {
 200             return None;
 201         }
 202         let results = self.bcx.inst_results(call_inst);
 203         assert_eq!(results.len(), 1);
 204         Some(results[0])
 205     }
 206
 207     pub fn easy_call(
 208         &mut self,
 209         name: &str,
 210         args: &[CValue<'tcx>],
 211         return_ty: Ty<'tcx>,
 212     ) -> CValue<'tcx> {
 213         let (input_tys, args): (Vec<_>, Vec<_>) = args
 214             .into_iter()
 215             .map(|arg| {
 216                 (
 217                     self.cton_type(arg.layout().ty).unwrap(),
 218                     arg.load_value(self),
 219                 )
 220             }).unzip();
 221         let return_layout = self.layout_of(return_ty);
 222         let return_ty = if let TypeVariants::TyTuple(tup) = return_ty.sty {
 223             if !tup.is_empty() {
 224                 bug!("easy_call( (...) -> <non empty tuple> ) is not allowed");
 225             }
 226             None
 227         } else {
 228             Some(self.cton_type(return_ty).unwrap())
 229         };
 230         if let Some(val) = self.lib_call(name, input_tys, return_ty, &args) {
 231             CValue::ByVal(val, return_layout)
 232         } else {
 233             CValue::ByRef(self.bcx.ins().iconst(types::I64, 0), return_layout)
 234         }
 235     }
 236
 237     fn self_sig(&self) -> FnSig<'tcx> {
 238         ty_fn_sig(self.tcx, self.instance.ty(self.tcx))
 239     }
 240
 241     fn return_type(&self) -> Ty<'tcx> {
 242         self.self_sig().output()
 243     }
 244 }
 245
 246 pub fn codegen_fn_prelude<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx>, start_ebb: Ebb) {
 247     let ssa_analyzed = crate::analyze::analyze(fx);
 248     fx.tcx.sess.warn(&format!("ssa {:?}", ssa_analyzed));
 249
 250     match fx.self_sig().abi {
 251         Abi::Rust | Abi::RustCall => {}
 252         _ => unimplemented!("declared function with non \"rust\" or \"rust-call\" abi"),
 253     }
 254
 255     let ret_layout = fx.layout_of(fx.return_type());
 256     let output_pass_mode = get_pass_mode(fx.tcx, fx.self_sig().abi, fx.return_type(), true);
 257     let ret_param = match output_pass_mode {
 258         PassMode::NoPass => None,
 259         PassMode::ByVal(_) => None,
 260         PassMode::ByRef => Some(fx.bcx.append_ebb_param(start_ebb, types::I64)),
 261     };
 262
 263     enum ArgKind {
 264         Normal(Value),
 265         Spread(Vec<Value>),
 266     }
 267
 268     let func_params = fx
 269         .mir
 270         .args_iter()
 271         .map(|local| {
 272             let arg_ty = fx.monomorphize(&fx.mir.local_decls[local].ty);
 273
 274             // Adapted from https://github.com/rust-lang/rust/blob/145155dc96757002c7b2e9de8489416e2fdbbd57/src/librustc_codegen_llvm/mir/mod.rs#L442-L482
 275             if Some(local) == fx.mir.spread_arg {
 276                 // This argument (e.g. the last argument in the "rust-call" ABI)
 277                 // is a tuple that was spread at the ABI level and now we have
 278                 // to reconstruct it into a tuple local variable, from multiple
 279                 // individual function arguments.
 280
 281                 let tupled_arg_tys = match arg_ty.sty {
 282                     ty::TyTuple(ref tys) => tys,
 283                     _ => bug!("spread argument isn't a tuple?! but {:?}", arg_ty),
 284                 };
 285
 286                 let mut ebb_params = Vec::new();
 287                 for arg_ty in tupled_arg_tys.iter() {
 288                     let cton_type =
 289                         get_pass_mode(fx.tcx, fx.self_sig().abi, arg_ty, false).get_param_ty(fx);
 290                     ebb_params.push(fx.bcx.append_ebb_param(start_ebb, cton_type));
 291                 }
 292
 293                 (local, ArgKind::Spread(ebb_params), arg_ty)
 294             } else {
 295                 let cton_type =
 296                     get_pass_mode(fx.tcx, fx.self_sig().abi, arg_ty, false).get_param_ty(fx);
 297                 (
 298                     local,
 299                     ArgKind::Normal(fx.bcx.append_ebb_param(start_ebb, cton_type)),
 300                     arg_ty,
 301                 )
 302             }
 303         }).collect::<Vec<(Local, ArgKind, Ty)>>();
 304
 305     fx.bcx.switch_to_block(start_ebb);
 306
 307     match output_pass_mode {
 308         PassMode::NoPass => {
 309             let null = fx.bcx.ins().iconst(types::I64, 0);
 310             //unimplemented!("pass mode nopass");
 311             fx.local_map.insert(
 312                 RETURN_PLACE,
 313                 CPlace::Addr(null, fx.layout_of(fx.return_type())),
 314             );
 315         }
 316         PassMode::ByVal(ret_ty) => {
 317             let var = Variable(RETURN_PLACE);
 318             fx.bcx.declare_var(var, ret_ty);
 319             fx.local_map
 320                 .insert(RETURN_PLACE, CPlace::Var(var, ret_layout));
 321         }
 322         PassMode::ByRef => {
 323             fx.local_map
 324                 .insert(RETURN_PLACE, CPlace::Addr(ret_param.unwrap(), ret_layout));
 325         }
 326     }
 327
 328     for (local, arg_kind, ty) in func_params {
 329         let layout = fx.layout_of(ty);
 330
 331         if let ArgKind::Normal(ebb_param) = arg_kind {
 332             if !ssa_analyzed
 333                 .get(&local)
 334                 .unwrap()
 335                 .contains(crate::analyze::Flags::NOT_SSA)
 336             {
 337                 let var = Variable(local);
 338                 fx.bcx.declare_var(var, fx.cton_type(ty).unwrap());
 339                 match get_pass_mode(fx.tcx, fx.self_sig().abi, ty, false) {
 340                     PassMode::NoPass => unimplemented!("pass mode nopass"),
 341                     PassMode::ByVal(_) => fx.bcx.def_var(var, ebb_param),
 342                     PassMode::ByRef => {
 343                         let val = CValue::ByRef(ebb_param, fx.layout_of(ty)).load_value(fx);
 344                         fx.bcx.def_var(var, val);
 345                     }
 346                 }
 347                 fx.local_map.insert(local, CPlace::Var(var, layout));
 348                 continue;
 349             }
 350         }
 351
 352         let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
 353             kind: StackSlotKind::ExplicitSlot,
 354             size: layout.size.bytes() as u32,
 355             offset: None,
 356         });
 357
 358         let place = CPlace::from_stack_slot(fx, stack_slot, ty);
 359
 360         match arg_kind {
 361             ArgKind::Normal(ebb_param) => match get_pass_mode(fx.tcx, fx.self_sig().abi, ty, false)
 362             {
 363                 PassMode::NoPass => unimplemented!("pass mode nopass"),
 364                 PassMode::ByVal(_) => {
 365                     place.write_cvalue(fx, CValue::ByVal(ebb_param, place.layout()))
 366                 }
 367                 PassMode::ByRef => place.write_cvalue(fx, CValue::ByRef(ebb_param, place.layout())),
 368             },
 369             ArgKind::Spread(ebb_params) => {
 370                 for (i, ebb_param) in ebb_params.into_iter().enumerate() {
 371                     let sub_place = place.place_field(fx, mir::Field::new(i));
 372                     match get_pass_mode(fx.tcx, fx.self_sig().abi, sub_place.layout().ty, false) {
 373                         PassMode::NoPass => unimplemented!("pass mode nopass"),
 374                         PassMode::ByVal(_) => {
 375                             sub_place.write_cvalue(fx, CValue::ByVal(ebb_param, sub_place.layout()))
 376                         }
 377                         PassMode::ByRef => {
 378                             sub_place.write_cvalue(fx, CValue::ByRef(ebb_param, sub_place.layout()))
 379                         }
 380                     }
 381                 }
 382             }
 383         }
 384         fx.local_map.insert(local, place);
 385     }
 386
 387     for local in fx.mir.vars_and_temps_iter() {
 388         let ty = fx.mir.local_decls[local].ty;
 389         let layout = fx.layout_of(ty);
 390
 391         let place = if ssa_analyzed
 392             .get(&local)
 393             .unwrap()
 394             .contains(crate::analyze::Flags::NOT_SSA)
 395         {
 396             let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
 397                 kind: StackSlotKind::ExplicitSlot,
 398                 size: layout.size.bytes() as u32,
 399                 offset: None,
 400             });
 401             CPlace::from_stack_slot(fx, stack_slot, ty)
 402         } else {
 403             let var = Variable(local);
 404             fx.bcx.declare_var(var, fx.cton_type(ty).unwrap());
 405             CPlace::Var(var, layout)
 406         };
 407
 408         fx.local_map.insert(local, place);
 409     }
 410
 411     fx.bcx
 412         .ins()
 413         .jump(*fx.ebb_map.get(&START_BLOCK).unwrap(), &[]);
 414 }
 415
 416 pub fn codegen_call<'a, 'tcx: 'a>(
 417     fx: &mut FunctionCx<'a, 'tcx>,
 418     func: &Operand<'tcx>,
 419     args: &[Operand<'tcx>],
 420     destination: &Option<(Place<'tcx>, BasicBlock)>,
 421 ) {
 422     let fn_ty = fx.monomorphize(&func.ty(&fx.mir.local_decls, fx.tcx));
 423     let sig = ty_fn_sig(fx.tcx, fn_ty);
 424
 425     // Unpack arguments tuple for closures
 426     let args = if sig.abi == Abi::RustCall {
 427         assert_eq!(args.len(), 2, "rust-call abi requires two arguments");
 428         let self_arg = trans_operand(fx, &args[0]);
 429         let pack_arg = trans_operand(fx, &args[1]);
 430         let mut args = Vec::new();
 431         args.push(self_arg);
 432         match pack_arg.layout().ty.sty {
 433             ty::TyTuple(ref tupled_arguments) => {
 434                 for (i, _) in tupled_arguments.iter().enumerate() {
 435                     args.push(pack_arg.value_field(fx, mir::Field::new(i)));
 436                 }
 437             }
 438             _ => bug!("argument to function with \"rust-call\" ABI is not a tuple"),
 439         }
 440         println!(
 441             "{:?} {:?}",
 442             pack_arg.layout().ty,
 443             args.iter().map(|a| a.layout().ty).collect::<Vec<_>>()
 444         );
 445         args
 446     } else {
 447         args.into_iter()
 448             .map(|arg| trans_operand(fx, arg))
 449             .collect::<Vec<_>>()
 450     };
 451
 452     let destination = destination
 453         .as_ref()
 454         .map(|(place, bb)| (trans_place(fx, place), *bb));
 455
 456     if codegen_intrinsic_call(fx, fn_ty, sig, &args, destination) {
 457         return;
 458     }
 459
 460     let ret_layout = fx.layout_of(sig.output());
 461
 462     let output_pass_mode = get_pass_mode(fx.tcx, sig.abi, sig.output(), true);
 463     println!("{:?}", output_pass_mode);
 464     let return_ptr = match output_pass_mode {
 465         PassMode::NoPass => None,
 466         PassMode::ByRef => match destination {
 467             Some((place, _)) => Some(place.expect_addr()),
 468             None => Some(fx.bcx.ins().iconst(types::I64, 0)),
 469         },
 470         PassMode::ByVal(_) => None,
 471     };
 472
 473     let call_args: Vec<Value> = return_ptr
 474         .into_iter()
 475         .chain(args.into_iter().map(|arg| {
 476             match get_pass_mode(fx.tcx, sig.abi, arg.layout().ty, false) {
 477                 PassMode::NoPass => unimplemented!("pass mode nopass"),
 478                 PassMode::ByVal(_) => arg.load_value(fx),
 479                 PassMode::ByRef => arg.force_stack(fx),
 480             }
 481         })).collect::<Vec<_>>();
 482
 483     let inst = match trans_operand(fx, func) {
 484         CValue::Func(func, _) => fx.bcx.ins().call(func, &call_args),
 485         func => {
 486             let func = func.load_value(fx);
 487             let sig = fx.bcx.import_signature(cton_sig_from_fn_ty(fx.tcx, fn_ty));
 488             fx.bcx.ins().call_indirect(sig, func, &call_args)
 489         }
 490     };
 491
 492     match output_pass_mode {
 493         PassMode::NoPass => {}
 494         PassMode::ByVal(_) => {
 495             if let Some((ret_place, _)) = destination {
 496                 let results = fx.bcx.inst_results(inst);
 497                 ret_place.write_cvalue(fx, CValue::ByVal(results[0], ret_layout));
 498             }
 499         }
 500         PassMode::ByRef => {}
 501     }
 502     if let Some((_, dest)) = destination {
 503         let ret_ebb = fx.get_ebb(dest);
 504         fx.bcx.ins().jump(ret_ebb, &[]);
 505     } else {
 506         fx.bcx.ins().trap(TrapCode::User(!0));
 507     }
 508 }
 509
 510 pub fn codegen_return(fx: &mut FunctionCx) {
 511     match get_pass_mode(fx.tcx, fx.self_sig().abi, fx.return_type(), true) {
 512         PassMode::NoPass | PassMode::ByRef => {
 513             fx.bcx.ins().return_(&[]);
 514         }
 515         PassMode::ByVal(_) => {
 516             let place = fx.get_local_place(RETURN_PLACE);
 517             let ret_val = place.to_cvalue(fx).load_value(fx);
 518             fx.bcx.ins().return_(&[ret_val]);
 519         }
 520     }
 521 }
 522
 523 fn codegen_intrinsic_call<'a, 'tcx: 'a>(
 524     fx: &mut FunctionCx<'a, 'tcx>,
 525     fn_ty: Ty<'tcx>,
 526     sig: FnSig<'tcx>,
 527     args: &[CValue<'tcx>],
 528     destination: Option<(CPlace<'tcx>, BasicBlock)>,
 529 ) -> bool {
 530     if let TypeVariants::TyFnDef(def_id, substs) = fn_ty.sty {
 531         if sig.abi == Abi::RustIntrinsic {
 532             let intrinsic = fx.tcx.item_name(def_id).as_str();
 533             let intrinsic = &intrinsic[..];
 534
 535             let ret = match destination {
 536                 Some((place, _)) => place,
 537                 None => {
 538                     // Insert non returning intrinsics here
 539                     match intrinsic {
 540                         "abort" => {
 541                             fx.bcx.ins().trap(TrapCode::User(!0 - 1));
 542                         }
 543                         "unreachable" => {
 544                             fx.bcx.ins().trap(TrapCode::User(!0 - 1));
 545                         }
 546                         _ => unimplemented!("unsupported instrinsic {}", intrinsic),
 547                     }
 548                     return true;
 549                 }
 550             };
 551
 552             let nil_ty = fx.tcx.mk_nil();
 553             let u64_layout = fx.layout_of(fx.tcx.types.u64);
 554             let usize_layout = fx.layout_of(fx.tcx.types.usize);
 555
 556             match intrinsic {
 557                 "assume" => {
 558                     assert_eq!(args.len(), 1);
 559                 }
 560                 "arith_offset" => {
 561                     assert_eq!(args.len(), 2);
 562                     let base = args[0].load_value(fx);
 563                     let offset = args[1].load_value(fx);
 564                     let res = fx.bcx.ins().iadd(base, offset);
 565                     let res = CValue::ByVal(res, ret.layout());
 566                     ret.write_cvalue(fx, res);
 567                 }
 568                 "likely" | "unlikely" => {
 569                     assert_eq!(args.len(), 1);
 570                     ret.write_cvalue(fx, args[0]);
 571                 }
 572                 "copy" | "copy_nonoverlapping" => {
 573                     let elem_ty = substs.type_at(0);
 574                     let elem_size: u64 = fx.layout_of(elem_ty).size.bytes();
 575                     let elem_size = fx.bcx.ins().iconst(types::I64, elem_size as i64);
 576                     assert_eq!(args.len(), 3);
 577                     let src = args[0];
 578                     let dst = args[1];
 579                     let count = args[2].load_value(fx);
 580                     let byte_amount = fx.bcx.ins().imul(count, elem_size);
 581                     fx.easy_call(
 582                         "memmove",
 583                         &[dst, src, CValue::ByVal(byte_amount, usize_layout)],
 584                         nil_ty,
 585                     );
 586                 }
 587                 "discriminant_value" => {
 588                     assert_eq!(args.len(), 1);
 589                     let discr = crate::base::trans_get_discriminant(fx, args[0], ret.layout());
 590                     ret.write_cvalue(fx, discr);
 591                 }
 592                 "size_of" => {
 593                     assert_eq!(args.len(), 0);
 594                     let size_of = fx.layout_of(substs.type_at(0)).size.bytes();
 595                     let size_of = CValue::const_val(fx, usize_layout.ty, size_of as i64);
 596                     ret.write_cvalue(fx, size_of);
 597                 }
 598                 "type_id" => {
 599                     assert_eq!(args.len(), 0);
 600                     let type_id = fx.tcx.type_id_hash(substs.type_at(0));
 601                     let type_id = CValue::const_val(fx, u64_layout.ty, type_id as i64);
 602                     ret.write_cvalue(fx, type_id);
 603                 }
 604                 "min_align_of" => {
 605                     assert_eq!(args.len(), 0);
 606                     let min_align = fx.layout_of(substs.type_at(0)).align.abi();
 607                     let min_align = CValue::const_val(fx, usize_layout.ty, min_align as i64);
 608                     ret.write_cvalue(fx, min_align);
 609                 }
 610                 _ if intrinsic.starts_with("unchecked_") => {
 611                     assert_eq!(args.len(), 2);
 612                     let bin_op = match intrinsic {
 613                         "unchecked_div" => BinOp::Div,
 614                         "unchecked_rem" => BinOp::Rem,
 615                         "unchecked_shl" => BinOp::Shl,
 616                         "unchecked_shr" => BinOp::Shr,
 617                         _ => unimplemented!("intrinsic {}", intrinsic),
 618                     };
 619                     let res = match ret.layout().ty.sty {
 620                         TypeVariants::TyUint(_) => crate::base::trans_int_binop(
 621                             fx,
 622                             bin_op,
 623                             args[0],
 624                             args[1],
 625                             ret.layout().ty,
 626                             false,
 627                         ),
 628                         TypeVariants::TyInt(_) => crate::base::trans_int_binop(
 629                             fx,
 630                             bin_op,
 631                             args[0],
 632                             args[1],
 633                             ret.layout().ty,
 634                             true,
 635                         ),
 636                         _ => panic!(),
 637                     };
 638                     ret.write_cvalue(fx, res);
 639                 }
 640                 _ if intrinsic.ends_with("_with_overflow") => {
 641                     assert_eq!(args.len(), 2);
 642                     assert_eq!(args[0].layout().ty, args[1].layout().ty);
 643                     let bin_op = match intrinsic {
 644                         "add_with_overflow" => BinOp::Add,
 645                         "sub_with_overflow" => BinOp::Sub,
 646                         "mul_with_overflow" => BinOp::Mul,
 647                         _ => unimplemented!("intrinsic {}", intrinsic),
 648                     };
 649                     let res = match args[0].layout().ty.sty {
 650                         TypeVariants::TyUint(_) => crate::base::trans_checked_int_binop(
 651                             fx,
 652                             bin_op,
 653                             args[0],
 654                             args[1],
 655                             ret.layout().ty,
 656                             false,
 657                         ),
 658                         TypeVariants::TyInt(_) => crate::base::trans_checked_int_binop(
 659                             fx,
 660                             bin_op,
 661                             args[0],
 662                             args[1],
 663                             ret.layout().ty,
 664                             true,
 665                         ),
 666                         _ => panic!(),
 667                     };
 668                     ret.write_cvalue(fx, res);
 669                 }
 670                 _ if intrinsic.starts_with("overflowing_") => {
 671                     assert_eq!(args.len(), 2);
 672                     assert_eq!(args[0].layout().ty, args[1].layout().ty);
 673                     let bin_op = match intrinsic {
 674                         "overflowing_add" => BinOp::Add,
 675                         "overflowing_sub" => BinOp::Sub,
 676                         "overflowing_mul" => BinOp::Mul,
 677                         _ => unimplemented!("intrinsic {}", intrinsic),
 678                     };
 679                     let res = match args[0].layout().ty.sty {
 680                         TypeVariants::TyUint(_) => crate::base::trans_int_binop(
 681                             fx,
 682                             bin_op,
 683                             args[0],
 684                             args[1],
 685                             ret.layout().ty,
 686                             false,
 687                         ),
 688                         TypeVariants::TyInt(_) => crate::base::trans_int_binop(
 689                             fx,
 690                             bin_op,
 691                             args[0],
 692                             args[1],
 693                             ret.layout().ty,
 694                             true,
 695                         ),
 696                         _ => panic!(),
 697                     };
 698                     ret.write_cvalue(fx, res);
 699                 }
 700                 "offset" => {
 701                     assert_eq!(args.len(), 2);
 702                     let base = args[0].load_value(fx);
 703                     let offset = args[1].load_value(fx);
 704                     let res = fx.bcx.ins().iadd(base, offset);
 705                     ret.write_cvalue(fx, CValue::ByVal(res, args[0].layout()));
 706                 }
 707                 "transmute" => {
 708                     assert_eq!(args.len(), 1);
 709                     let src_ty = substs.type_at(0);
 710                     let dst_ty = substs.type_at(1);
 711                     assert_eq!(args[0].layout().ty, src_ty);
 712                     let addr = args[0].force_stack(fx);
 713                     let dst_layout = fx.layout_of(dst_ty);
 714                     ret.write_cvalue(fx, CValue::ByRef(addr, dst_layout))
 715                 }
 716                 "uninit" => {
 717                     assert_eq!(args.len(), 0);
 718                     let ty = substs.type_at(0);
 719                     let layout = fx.layout_of(ty);
 720                     let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
 721                         kind: StackSlotKind::ExplicitSlot,
 722                         size: layout.size.bytes() as u32,
 723                         offset: None,
 724                     });
 725
 726                     let uninit_place = CPlace::from_stack_slot(fx, stack_slot, ty);
 727                     let uninit_val = uninit_place.to_cvalue(fx);
 728                     ret.write_cvalue(fx, uninit_val);
 729                 }
 730                 "ctlz" | "ctlz_nonzero" => {
 731                     assert_eq!(args.len(), 1);
 732                     let arg = args[0].load_value(fx);
 733                     let res = CValue::ByVal(fx.bcx.ins().clz(arg), args[0].layout());
 734                     ret.write_cvalue(fx, res);
 735                 }
 736                 "cttz" | "cttz_nonzero" => {
 737                     assert_eq!(args.len(), 1);
 738                     let arg = args[0].load_value(fx);
 739                     let res = CValue::ByVal(fx.bcx.ins().clz(arg), args[0].layout());
 740                     ret.write_cvalue(fx, res);
 741                 }
 742                 "ctpop" => {
 743                     assert_eq!(args.len(), 1);
 744                     let arg = args[0].load_value(fx);
 745                     let res = CValue::ByVal(fx.bcx.ins().popcnt(arg), args[0].layout());
 746                     ret.write_cvalue(fx, res);
 747                 }
 748                 _ => unimpl!("unsupported intrinsic {}", intrinsic),
 749             }
 750
 751             if let Some((_, dest)) = destination {
 752                 let ret_ebb = fx.get_ebb(dest);
 753                 fx.bcx.ins().jump(ret_ebb, &[]);
 754             } else {
 755                 fx.bcx.ins().trap(TrapCode::User(!0));
 756             }
 757             return true;
 758         }
 759     }
 760
 761     false
 762 }