src/base.rs

   1 use crate::prelude::*;
   2
   3 struct PrintOnPanic<F: Fn() -> String>(F);
   4 impl<F: Fn() -> String> Drop for PrintOnPanic<F> {
   5     fn drop(&mut self) {
   6         if ::std::thread::panicking() {
   7             println!("{}", (self.0)());
   8         }
   9     }
  10 }
  11
  12 pub fn trans_mono_item<'a, 'tcx: 'a>(
  13     tcx: TyCtxt<'a, 'tcx, 'tcx>,
  14     module: &mut Module<impl Backend>,
  15     caches: &mut Caches<'tcx>,
  16     ccx: &mut crate::constant::ConstantCx,
  17     mono_item: MonoItem<'tcx>,
  18 ) {
  19     match mono_item {
  20         MonoItem::Fn(inst) => {
  21             let _inst_guard = PrintOnPanic(|| format!("{:?}", inst));
  22             let _mir_guard = PrintOnPanic(|| {
  23                 match inst.def {
  24                     InstanceDef::Item(_)
  25                     | InstanceDef::DropGlue(_, _)
  26                     | InstanceDef::Virtual(_, _)
  27                         if inst.def_id().krate == LOCAL_CRATE =>
  28                     {
  29                         let mut mir = ::std::io::Cursor::new(Vec::new());
  30                         crate::rustc_mir::util::write_mir_pretty(
  31                             tcx,
  32                             Some(inst.def_id()),
  33                             &mut mir,
  34                         )
  35                         .unwrap();
  36                         String::from_utf8(mir.into_inner()).unwrap()
  37                     }
  38                     _ => {
  39                         // FIXME fix write_mir_pretty for these instances
  40                         format!("{:#?}", tcx.instance_mir(inst.def))
  41                     }
  42                 }
  43             });
  44
  45             trans_fn(tcx, module, ccx, caches, inst);
  46         }
  47         MonoItem::Static(def_id) => {
  48             crate::constant::codegen_static(ccx, def_id);
  49         }
  50         MonoItem::GlobalAsm(node_id) => tcx
  51             .sess
  52             .fatal(&format!("Unimplemented global asm mono item {:?}", node_id)),
  53     }
  54 }
  55
  56 fn trans_fn<'a, 'tcx: 'a>(
  57     tcx: TyCtxt<'a, 'tcx, 'tcx>,
  58     module: &mut Module<impl Backend>,
  59     constants: &mut crate::constant::ConstantCx,
  60     caches: &mut Caches<'tcx>,
  61     instance: Instance<'tcx>,
  62 ) {
  63     // Step 1. Get mir
  64     let mir = tcx.instance_mir(instance.def);
  65
  66     // Step 2. Declare function
  67     let (name, sig) = get_function_name_and_sig(tcx, instance);
  68     let func_id = module
  69         .declare_function(&name, Linkage::Export, &sig)
  70         .unwrap();
  71
  72     // Step 3. Make FunctionBuilder
  73     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
  74     let mut func_ctx = FunctionBuilderContext::new();
  75     let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut func, &mut func_ctx);
  76
  77     // Step 4. Predefine ebb's
  78     let start_ebb = bcx.create_ebb();
  79     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
  80     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
  81         ebb_map.insert(bb, bcx.create_ebb());
  82     }
  83
  84     // Step 5. Make FunctionCx
  85     let pointer_type = module.target_config().pointer_type();
  86     let mut fx = FunctionCx {
  87         tcx,
  88         module,
  89         pointer_type,
  90         instance,
  91         mir,
  92         bcx,
  93         param_substs: {
  94             assert!(!instance.substs.needs_infer());
  95             instance.substs
  96         },
  97         ebb_map,
  98         local_map: HashMap::new(),
  99         comments: HashMap::new(),
 100         constants,
 101         caches,
 102
 103         top_nop: None,
 104     };
 105
 106     // Step 6. Codegen function
 107     crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
 108     codegen_fn_content(&mut fx);
 109
 110     // Step 7. Write function to file for debugging
 111     let mut writer = crate::pretty_clif::CommentWriter(fx.comments);
 112
 113     let mut cton = String::new();
 114     if cfg!(debug_assertions) {
 115         ::cranelift::codegen::write::decorate_function(&mut writer, &mut cton, &func, None)
 116             .unwrap();
 117         let clif_file_name = format!(
 118             "{}/{}__{}.clif",
 119             concat!(env!("CARGO_MANIFEST_DIR"), "/target/out/clif"),
 120             tcx.crate_name(LOCAL_CRATE),
 121             tcx.symbol_name(instance).as_str(),
 122         );
 123         if let Err(e) = ::std::fs::write(clif_file_name, cton.as_bytes()) {
 124             tcx.sess.warn(&format!("err writing clif file: {:?}", e));
 125         }
 126     }
 127
 128     // Step 8. Verify function
 129     verify_func(tcx, writer, &func);
 130
 131     // Step 9. Define function
 132     // TODO: cranelift doesn't yet support some of the things needed
 133     if should_codegen(tcx.sess) {
 134         caches.context.func = func;
 135         module
 136             .define_function(func_id, &mut caches.context)
 137             .unwrap();
 138         caches.context.clear();
 139     }
 140 }
 141
 142 fn verify_func(tcx: TyCtxt, writer: crate::pretty_clif::CommentWriter, func: &Function) {
 143     let flags = settings::Flags::new(settings::builder());
 144     match ::cranelift::codegen::verify_function(&func, &flags) {
 145         Ok(_) => {}
 146         Err(err) => {
 147             tcx.sess.err(&format!("{:?}", err));
 148             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 149                 &func,
 150                 None,
 151                 Some(Box::new(writer)),
 152                 err,
 153             );
 154             tcx.sess
 155                 .fatal(&format!("cretonne verify error:\n{}", pretty_error));
 156         }
 157     }
 158 }
 159
 160 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 161     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 162         if bb_data.is_cleanup {
 163             // Unwinding after panicking is not supported
 164             continue;
 165         }
 166
 167         let ebb = fx.get_ebb(bb);
 168         fx.bcx.switch_to_block(ebb);
 169
 170         fx.bcx.ins().nop();
 171         for stmt in &bb_data.statements {
 172             trans_stmt(fx, ebb, stmt);
 173         }
 174
 175         let mut terminator_head = "\n".to_string();
 176         bb_data
 177             .terminator()
 178             .kind
 179             .fmt_head(&mut terminator_head)
 180             .unwrap();
 181         let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 182         fx.add_comment(inst, terminator_head);
 183
 184         match &bb_data.terminator().kind {
 185             TerminatorKind::Goto { target } => {
 186                 let ebb = fx.get_ebb(*target);
 187                 fx.bcx.ins().jump(ebb, &[]);
 188             }
 189             TerminatorKind::Return => {
 190                 crate::abi::codegen_return(fx);
 191             }
 192             TerminatorKind::Assert {
 193                 cond,
 194                 expected,
 195                 msg: _,
 196                 target,
 197                 cleanup: _,
 198             } => {
 199                 let cond = trans_operand(fx, cond).load_value(fx);
 200                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 201                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 202                 let target = fx.get_ebb(*target);
 203                 if *expected {
 204                     fx.bcx.ins().brnz(cond, target, &[]);
 205                 } else {
 206                     fx.bcx.ins().brz(cond, target, &[]);
 207                 };
 208                 fx.bcx.ins().trap(TrapCode::User(!0));
 209             }
 210
 211             TerminatorKind::SwitchInt {
 212                 discr,
 213                 switch_ty: _,
 214                 values,
 215                 targets,
 216             } => {
 217                 let discr = trans_operand(fx, discr).load_value(fx);
 218                 let mut switch = ::cranelift::frontend::Switch::new();
 219                 for (i, value) in values.iter().enumerate() {
 220                     let ebb = fx.get_ebb(targets[i]);
 221                     switch.set_entry(*value as u64, ebb);
 222                 }
 223                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 224                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 225             }
 226             TerminatorKind::Call {
 227                 func,
 228                 args,
 229                 destination,
 230                 cleanup: _,
 231                 from_hir_call: _,
 232             } => {
 233                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 234             }
 235             TerminatorKind::Resume | TerminatorKind::Abort | TerminatorKind::Unreachable => {
 236                 fx.bcx.ins().trap(TrapCode::User(!0));
 237             }
 238             TerminatorKind::Yield { .. }
 239             | TerminatorKind::FalseEdges { .. }
 240             | TerminatorKind::FalseUnwind { .. }
 241             | TerminatorKind::DropAndReplace { .. } => {
 242                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 243             }
 244             TerminatorKind::Drop {
 245                 location,
 246                 target,
 247                 unwind: _,
 248             } => {
 249                 let ty = location.ty(fx.mir, fx.tcx).to_ty(fx.tcx);
 250                 let ty = fx.monomorphize(&ty);
 251                 let drop_fn = crate::rustc_mir::monomorphize::resolve_drop_in_place(fx.tcx, ty);
 252
 253                 if let ty::InstanceDef::DropGlue(_, None) = drop_fn.def {
 254                     // we don't actually need to drop anything
 255                 } else {
 256                     let drop_place = trans_place(fx, location);
 257                     let arg_place = CPlace::temp(
 258                         fx,
 259                         fx.tcx.mk_ref(
 260                             &ty::RegionKind::ReErased,
 261                             TypeAndMut {
 262                                 ty,
 263                                 mutbl: crate::rustc::hir::Mutability::MutMutable,
 264                             },
 265                         ),
 266                     );
 267                     drop_place.write_place_ref(fx, arg_place);
 268                     match ty.sty {
 269                         ty::Dynamic(..) => {
 270                             unimplemented!("Drop for trait object");
 271                         }
 272                         _ => {
 273                             let drop_fn_ty = drop_fn.ty(fx.tcx);
 274                             let arg_value = arg_place.to_cvalue(fx);
 275                             crate::abi::codegen_call_inner(
 276                                 fx,
 277                                 None,
 278                                 drop_fn_ty,
 279                                 vec![arg_value],
 280                                 None,
 281                             );
 282                         }
 283                     }
 284                     /*
 285                     let (args1, args2);
 286                     /*let mut args = if let Some(llextra) = place.llextra {
 287                         args2 = [place.llval, llextra];
 288                         &args2[..]
 289                     } else {
 290                         args1 = [place.llval];
 291                         &args1[..]
 292                     };*/
 293                     let (drop_fn, fn_ty) = match ty.sty {
 294                     ty::Dynamic(..) => {
 295                     let fn_ty = drop_fn.ty(bx.cx.tcx);
 296                     let sig = common::ty_fn_sig(bx.cx, fn_ty);
 297                     let sig = bx.tcx().normalize_erasing_late_bound_regions(
 298                     ty::ParamEnv::reveal_all(),
 299                     &sig,
 300                     );
 301                     let fn_ty = FnType::new_vtable(bx.cx, sig, &[]);
 302                     let vtable = args[1];
 303                     args = &args[..1];
 304                     (meth::DESTRUCTOR.get_fn(&bx, vtable, &fn_ty), fn_ty)
 305                     }
 306                     _ => {
 307                     let value = place.to_cvalue(fx);
 308                     (callee::get_fn(bx.cx, drop_fn),
 309                     FnType::of_instance(bx.cx, &drop_fn))
 310                     }
 311                     };
 312                     do_call(self, bx, fn_ty, drop_fn, args,
 313                     Some((ReturnDest::Nothing, target)),
 314                     unwind);*/
 315                 }
 316
 317                 let target_ebb = fx.get_ebb(*target);
 318                 fx.bcx.ins().jump(target_ebb, &[]);
 319             }
 320             TerminatorKind::GeneratorDrop => {
 321                 unimplemented!("terminator GeneratorDrop");
 322             }
 323         };
 324     }
 325
 326     fx.bcx.seal_all_blocks();
 327     fx.bcx.finalize();
 328 }
 329
 330 fn trans_stmt<'a, 'tcx: 'a>(
 331     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 332     cur_ebb: Ebb,
 333     stmt: &Statement<'tcx>,
 334 ) {
 335     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 336
 337     match &stmt.kind {
 338         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 339         _ => {
 340             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 341             fx.add_comment(inst, format!("{:?}", stmt));
 342         }
 343     }
 344
 345     match &stmt.kind {
 346         StatementKind::SetDiscriminant {
 347             place,
 348             variant_index,
 349         } => {
 350             let place = trans_place(fx, place);
 351             let layout = place.layout();
 352             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 353                 return;
 354             }
 355             match layout.variants {
 356                 layout::Variants::Single { index } => {
 357                     assert_eq!(index, *variant_index);
 358                 }
 359                 layout::Variants::Tagged { .. } => {
 360                     let ptr = place.place_field(fx, mir::Field::new(0));
 361                     let to = layout
 362                         .ty
 363                         .ty_adt_def()
 364                         .unwrap()
 365                         .discriminant_for_variant(fx.tcx, *variant_index)
 366                         .val;
 367                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 368                     ptr.write_cvalue(fx, discr);
 369                 }
 370                 layout::Variants::NicheFilling {
 371                     dataful_variant,
 372                     ref niche_variants,
 373                     niche_start,
 374                     ..
 375                 } => {
 376                     if *variant_index != dataful_variant {
 377                         let niche = place.place_field(fx, mir::Field::new(0));
 378                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 379                         let niche_value = ((variant_index - *niche_variants.start()) as u128)
 380                             .wrapping_add(niche_start);
 381                         // FIXME(eddyb) Check the actual primitive type here.
 382                         let niche_llval = if niche_value == 0 {
 383                             CValue::const_val(fx, niche.layout().ty, 0)
 384                         } else {
 385                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 386                         };
 387                         niche.write_cvalue(fx, niche_llval);
 388                     }
 389                 }
 390             }
 391         }
 392         StatementKind::Assign(to_place, rval) => {
 393             let lval = trans_place(fx, to_place);
 394             let dest_layout = lval.layout();
 395             match &**rval {
 396                 Rvalue::Use(operand) => {
 397                     let val = trans_operand(fx, operand);
 398                     lval.write_cvalue(fx, val);
 399                 }
 400                 Rvalue::Ref(_, _, place) => {
 401                     let place = trans_place(fx, place);
 402                     place.write_place_ref(fx, lval);
 403                 }
 404                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 405                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 406                     let lhs = trans_operand(fx, lhs);
 407                     let rhs = trans_operand(fx, rhs);
 408
 409                     let res = match ty.sty {
 410                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 411                         ty::Uint(_) => {
 412                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 413                         }
 414                         ty::Int(_) => {
 415                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 416                         }
 417                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 418                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 419                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 420                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 421                     };
 422                     lval.write_cvalue(fx, res);
 423                 }
 424                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 425                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 426                     let lhs = trans_operand(fx, lhs);
 427                     let rhs = trans_operand(fx, rhs);
 428
 429                     let res = match ty.sty {
 430                         ty::Uint(_) => {
 431                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 432                         }
 433                         ty::Int(_) => {
 434                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 435                         }
 436                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 437                     };
 438                     lval.write_cvalue(fx, res);
 439                 }
 440                 Rvalue::UnaryOp(un_op, operand) => {
 441                     let operand = trans_operand(fx, operand);
 442                     let layout = operand.layout();
 443                     let val = operand.load_value(fx);
 444                     let res = match un_op {
 445                         UnOp::Not => {
 446                             match layout.ty.sty {
 447                                 ty::Bool => {
 448                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 449                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 450                                     fx.bcx.ins().bint(types::I8, res)
 451                                 }
 452                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 453                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 454                             }
 455                         }
 456                         UnOp::Neg => match layout.ty.sty {
 457                             ty::Int(_) => {
 458                                 let clif_ty = fx.cton_type(layout.ty).unwrap();
 459                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 460                                 fx.bcx.ins().isub(zero, val)
 461                             }
 462                             ty::Float(_) => fx.bcx.ins().fneg(val),
 463                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 464                         },
 465                     };
 466                     lval.write_cvalue(fx, CValue::ByVal(res, layout));
 467                 }
 468                 Rvalue::Cast(CastKind::ReifyFnPointer, operand, ty) => {
 469                     let operand = trans_operand(fx, operand);
 470                     let layout = fx.layout_of(ty);
 471                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 472                 }
 473                 Rvalue::Cast(CastKind::UnsafeFnPointer, operand, ty) => {
 474                     let operand = trans_operand(fx, operand);
 475                     let layout = fx.layout_of(ty);
 476                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 477                 }
 478                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 479                     let operand = trans_operand(fx, operand);
 480                     let from_ty = operand.layout().ty;
 481                     match (&from_ty.sty, &to_ty.sty) {
 482                         (ty::Ref(..), ty::Ref(..))
 483                         | (ty::Ref(..), ty::RawPtr(..))
 484                         | (ty::RawPtr(..), ty::Ref(..))
 485                         | (ty::RawPtr(..), ty::RawPtr(..)) => {
 486                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 487                         }
 488                         (ty::RawPtr(..), ty::Uint(_)) | (ty::FnPtr(..), ty::Uint(_))
 489                             if to_ty.sty == fx.tcx.types.usize.sty =>
 490                         {
 491                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 492                         }
 493                         (ty::Uint(_), ty::RawPtr(..)) if from_ty.sty == fx.tcx.types.usize.sty => {
 494                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 495                         }
 496                         (ty::Char, ty::Uint(_))
 497                         | (ty::Uint(_), ty::Char)
 498                         | (ty::Uint(_), ty::Int(_))
 499                         | (ty::Uint(_), ty::Uint(_)) => {
 500                             let from = operand.load_value(fx);
 501                             let res = crate::common::cton_intcast(
 502                                 fx,
 503                                 from,
 504                                 fx.cton_type(to_ty).unwrap(),
 505                                 false,
 506                             );
 507                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 508                         }
 509                         (ty::Int(_), ty::Int(_)) | (ty::Int(_), ty::Uint(_)) => {
 510                             let from = operand.load_value(fx);
 511                             let res = crate::common::cton_intcast(
 512                                 fx,
 513                                 from,
 514                                 fx.cton_type(to_ty).unwrap(),
 515                                 true,
 516                             );
 517                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 518                         }
 519                         (ty::Float(from_flt), ty::Float(to_flt)) => {
 520                             let from = operand.load_value(fx);
 521                             let res = match (from_flt, to_flt) {
 522                                 (FloatTy::F32, FloatTy::F64) => {
 523                                     fx.bcx.ins().fpromote(types::F64, from)
 524                                 }
 525                                 (FloatTy::F64, FloatTy::F32) => {
 526                                     fx.bcx.ins().fdemote(types::F32, from)
 527                                 }
 528                                 _ => from,
 529                             };
 530                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 531                         }
 532                         (ty::Int(_), ty::Float(_)) => {
 533                             let from_ty = fx.cton_type(from_ty).unwrap();
 534                             let from = operand.load_value(fx);
 535                             // FIXME missing encoding for fcvt_from_sint.f32.i8
 536                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 537                                 fx.bcx.ins().sextend(types::I32, from)
 538                             } else {
 539                                 from
 540                             };
 541                             let f_type = fx.cton_type(to_ty).unwrap();
 542                             let res = fx.bcx.ins().fcvt_from_sint(f_type, from);
 543                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 544                         }
 545                         (ty::Uint(_), ty::Float(_)) => {
 546                             let from_ty = fx.cton_type(from_ty).unwrap();
 547                             let from = operand.load_value(fx);
 548                             // FIXME missing encoding for fcvt_from_uint.f32.i8
 549                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 550                                 fx.bcx.ins().uextend(types::I32, from)
 551                             } else {
 552                                 from
 553                             };
 554                             let f_type = fx.cton_type(to_ty).unwrap();
 555                             let res = fx.bcx.ins().fcvt_from_uint(f_type, from);
 556                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 557                         }
 558                         (ty::Bool, ty::Uint(_)) | (ty::Bool, ty::Int(_)) => {
 559                             let to_ty = fx.cton_type(to_ty).unwrap();
 560                             let from = operand.load_value(fx);
 561                             let res = if to_ty != types::I8 {
 562                                 fx.bcx.ins().uextend(to_ty, from)
 563                             } else {
 564                                 from
 565                             };
 566                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 567                         }
 568                         _ => unimpl!("rval misc {:?} {:?}", from_ty, to_ty),
 569                     }
 570                 }
 571                 Rvalue::Cast(CastKind::ClosureFnPointer, operand, ty) => {
 572                     unimplemented!("rval closure_fn_ptr {:?} {:?}", operand, ty)
 573                 }
 574                 Rvalue::Cast(CastKind::Unsize, operand, _ty) => {
 575                     let operand = trans_operand(fx, operand);
 576                     operand.unsize_value(fx, lval);
 577                 }
 578                 Rvalue::Discriminant(place) => {
 579                     let place = trans_place(fx, place).to_cvalue(fx);
 580                     let discr = trans_get_discriminant(fx, place, dest_layout);
 581                     lval.write_cvalue(fx, discr);
 582                 }
 583                 Rvalue::Repeat(operand, times) => {
 584                     let operand = trans_operand(fx, operand);
 585                     for i in 0..*times {
 586                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 587                         let to = lval.place_index(fx, index);
 588                         to.write_cvalue(fx, operand);
 589                     }
 590                 }
 591                 Rvalue::Len(place) => {
 592                     let place = trans_place(fx, place);
 593                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 594                     let len = match place.layout().ty.sty {
 595                         ty::Array(_elem_ty, len) => {
 596                             let len = crate::constant::force_eval_const(fx, len)
 597                                 .unwrap_usize(fx.tcx) as i64;
 598                             fx.bcx.ins().iconst(fx.pointer_type, len)
 599                         }
 600                         ty::Slice(_elem_ty) => match place {
 601                             CPlace::Addr(_, size, _) => size.unwrap(),
 602                             CPlace::Var(_, _) => unreachable!(),
 603                         },
 604                         _ => bug!("Rvalue::Len({:?})", place),
 605                     };
 606                     lval.write_cvalue(fx, CValue::ByVal(len, usize_layout));
 607                 }
 608                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 609                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 610
 611                     let usize_type = fx.cton_type(fx.tcx.types.usize).unwrap();
 612                     let (size, align) = fx.layout_of(content_ty).size_and_align();
 613                     let llsize = fx.bcx.ins().iconst(usize_type, size.bytes() as i64);
 614                     let llalign = fx.bcx.ins().iconst(usize_type, align.abi() as i64);
 615                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 616
 617                     // Allocate space:
 618                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 619                         Ok(id) => id,
 620                         Err(s) => {
 621                             fx.tcx
 622                                 .sess
 623                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 624                         }
 625                     };
 626                     let instance = ty::Instance::mono(fx.tcx, def_id);
 627                     let func_ref = fx.get_function_ref(instance);
 628                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 629                     let ptr = fx.bcx.inst_results(call)[0];
 630                     lval.write_cvalue(fx, CValue::ByVal(ptr, box_layout));
 631                 }
 632                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 633                     assert!(
 634                         lval.layout()
 635                             .ty
 636                             .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
 637                     );
 638                     let ty_size = fx.layout_of(ty).size.bytes();
 639                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 640                     lval.write_cvalue(fx, val);
 641                 }
 642                 Rvalue::Aggregate(kind, operands) => match **kind {
 643                     AggregateKind::Array(_ty) => {
 644                         for (i, operand) in operands.into_iter().enumerate() {
 645                             let operand = trans_operand(fx, operand);
 646                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 647                             let to = lval.place_index(fx, index);
 648                             to.write_cvalue(fx, operand);
 649                         }
 650                     }
 651                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 652                 },
 653             }
 654         }
 655         StatementKind::StorageLive(_)
 656         | StatementKind::StorageDead(_)
 657         | StatementKind::Nop
 658         | StatementKind::FakeRead(..)
 659         | StatementKind::EndRegion(_)
 660         | StatementKind::Retag { .. }
 661         | StatementKind::AscribeUserType(..) => {}
 662
 663         StatementKind::InlineAsm { .. } => unimpl!("Inline assembly is not supported"),
 664     }
 665 }
 666
 667 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 668     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 669     value: CValue<'tcx>,
 670     dest_layout: TyLayout<'tcx>,
 671 ) -> CValue<'tcx> {
 672     let layout = value.layout();
 673
 674     if layout.abi == layout::Abi::Uninhabited {
 675         fx.bcx.ins().trap(TrapCode::User(!0));
 676     }
 677     match layout.variants {
 678         layout::Variants::Single { index } => {
 679             let discr_val = layout.ty.ty_adt_def().map_or(index as u128, |def| {
 680                 def.discriminant_for_variant(fx.tcx, index).val
 681             });
 682             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 683         }
 684         layout::Variants::Tagged { .. } | layout::Variants::NicheFilling { .. } => {}
 685     }
 686
 687     let discr = value.value_field(fx, mir::Field::new(0));
 688     let discr_ty = discr.layout().ty;
 689     let lldiscr = discr.load_value(fx);
 690     match layout.variants {
 691         layout::Variants::Single { .. } => bug!(),
 692         layout::Variants::Tagged { ref tag, .. } => {
 693             let signed = match tag.value {
 694                 layout::Int(_, signed) => signed,
 695                 _ => false,
 696             };
 697             let val = cton_intcast(fx, lldiscr, fx.cton_type(dest_layout.ty).unwrap(), signed);
 698             return CValue::ByVal(val, dest_layout);
 699         }
 700         layout::Variants::NicheFilling {
 701             dataful_variant,
 702             ref niche_variants,
 703             niche_start,
 704             ..
 705         } => {
 706             let niche_llty = fx.cton_type(discr_ty).unwrap();
 707             let dest_cton_ty = fx.cton_type(dest_layout.ty).unwrap();
 708             if niche_variants.start() == niche_variants.end() {
 709                 let b = fx
 710                     .bcx
 711                     .ins()
 712                     .icmp_imm(IntCC::Equal, lldiscr, niche_start as u64 as i64);
 713                 let if_true = fx
 714                     .bcx
 715                     .ins()
 716                     .iconst(dest_cton_ty, *niche_variants.start() as u64 as i64);
 717                 let if_false = fx
 718                     .bcx
 719                     .ins()
 720                     .iconst(dest_cton_ty, dataful_variant as u64 as i64);
 721                 let val = fx.bcx.ins().select(b, if_true, if_false);
 722                 return CValue::ByVal(val, dest_layout);
 723             } else {
 724                 // Rebase from niche values to discriminant values.
 725                 let delta = niche_start.wrapping_sub(*niche_variants.start() as u128);
 726                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 727                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 728                 let b = fx.bcx.ins().icmp_imm(
 729                     IntCC::UnsignedLessThanOrEqual,
 730                     lldiscr,
 731                     *niche_variants.end() as u64 as i64,
 732                 );
 733                 let if_true =
 734                     cton_intcast(fx, lldiscr, fx.cton_type(dest_layout.ty).unwrap(), false);
 735                 let if_false = fx
 736                     .bcx
 737                     .ins()
 738                     .iconst(dest_cton_ty, dataful_variant as u64 as i64);
 739                 let val = fx.bcx.ins().select(b, if_true, if_false);
 740                 return CValue::ByVal(val, dest_layout);
 741             }
 742         }
 743     }
 744 }
 745
 746 macro_rules! binop_match {
 747     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 748         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 749     };
 750     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 751         assert_eq!($fx.tcx.types.bool, $ret_ty);
 752         let ret_layout = $fx.layout_of($ret_ty);
 753
 754         // TODO HACK no encoding for icmp.i8
 755         use crate::common::cton_intcast;
 756         let (lhs, rhs) = (
 757             cton_intcast($fx, $lhs, types::I64, $signed),
 758             cton_intcast($fx, $rhs, types::I64, $signed),
 759         );
 760         let b = $fx.bcx.ins().icmp(IntCC::$cc, lhs, rhs);
 761
 762         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 763     }};
 764     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 765         assert_eq!($fx.tcx.types.bool, $ret_ty);
 766         let ret_layout = $fx.layout_of($ret_ty);
 767         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 768         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 769     }};
 770     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 771         $body
 772     }};
 773     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 774         let ret_layout = $fx.layout_of($ret_ty);
 775         CValue::ByVal($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 776     }};
 777     (
 778         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 779         $(
 780             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 781         )*
 782     ) => {{
 783         let lhs = $lhs.load_value($fx);
 784         let rhs = $rhs.load_value($fx);
 785         match ($bin_op, $signed) {
 786             $(
 787                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 788             )*
 789         }
 790     }}
 791 }
 792
 793 fn trans_bool_binop<'a, 'tcx: 'a>(
 794     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 795     bin_op: BinOp,
 796     lhs: CValue<'tcx>,
 797     rhs: CValue<'tcx>,
 798     ty: Ty<'tcx>,
 799 ) -> CValue<'tcx> {
 800     let res = binop_match! {
 801         fx, bin_op, false, lhs, rhs, ty, "bool";
 802         Add (_) bug;
 803         Sub (_) bug;
 804         Mul (_) bug;
 805         Div (_) bug;
 806         Rem (_) bug;
 807         BitXor (_) bxor;
 808         BitAnd (_) band;
 809         BitOr (_) bor;
 810         Shl (_) bug;
 811         Shr (_) bug;
 812
 813         Eq (_) icmp(Equal);
 814         Lt (_) icmp(UnsignedLessThan);
 815         Le (_) icmp(UnsignedLessThanOrEqual);
 816         Ne (_) icmp(NotEqual);
 817         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 818         Gt (_) icmp(UnsignedGreaterThan);
 819
 820         Offset (_) bug;
 821     };
 822
 823     res
 824 }
 825
 826 pub fn trans_int_binop<'a, 'tcx: 'a>(
 827     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 828     bin_op: BinOp,
 829     lhs: CValue<'tcx>,
 830     rhs: CValue<'tcx>,
 831     out_ty: Ty<'tcx>,
 832     signed: bool,
 833 ) -> CValue<'tcx> {
 834     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 835         assert_eq!(
 836             lhs.layout().ty,
 837             rhs.layout().ty,
 838             "int binop requires lhs and rhs of same type"
 839         );
 840     }
 841     binop_match! {
 842         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 843         Add (_) iadd;
 844         Sub (_) isub;
 845         Mul (_) imul;
 846         Div (false) udiv;
 847         Div (true) sdiv;
 848         Rem (false) urem;
 849         Rem (true) srem;
 850         BitXor (_) bxor;
 851         BitAnd (_) band;
 852         BitOr (_) bor;
 853         Shl (_) ishl;
 854         Shr (false) ushr;
 855         Shr (true) sshr;
 856
 857         Eq (_) icmp(Equal);
 858         Lt (false) icmp(UnsignedLessThan);
 859         Lt (true) icmp(SignedLessThan);
 860         Le (false) icmp(UnsignedLessThanOrEqual);
 861         Le (true) icmp(SignedLessThanOrEqual);
 862         Ne (_) icmp(NotEqual);
 863         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 864         Ge (true) icmp(SignedGreaterThanOrEqual);
 865         Gt (false) icmp(UnsignedGreaterThan);
 866         Gt (true) icmp(SignedGreaterThan);
 867
 868         Offset (_) bug;
 869     }
 870 }
 871
 872 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 873     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 874     bin_op: BinOp,
 875     in_lhs: CValue<'tcx>,
 876     in_rhs: CValue<'tcx>,
 877     out_ty: Ty<'tcx>,
 878     signed: bool,
 879 ) -> CValue<'tcx> {
 880     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 881         assert_eq!(
 882             in_lhs.layout().ty,
 883             in_rhs.layout().ty,
 884             "checked int binop requires lhs and rhs of same type"
 885         );
 886     }
 887
 888     let lhs = in_lhs.load_value(fx);
 889     let rhs = in_rhs.load_value(fx);
 890     let res = match bin_op {
 891         BinOp::Add => fx.bcx.ins().iadd(lhs, rhs),
 892         BinOp::Sub => fx.bcx.ins().isub(lhs, rhs),
 893         BinOp::Mul => fx.bcx.ins().imul(lhs, rhs),
 894         BinOp::Shl => fx.bcx.ins().ishl(lhs, rhs),
 895         BinOp::Shr => {
 896             if !signed {
 897                 fx.bcx.ins().ushr(lhs, rhs)
 898             } else {
 899                 fx.bcx.ins().sshr(lhs, rhs)
 900             }
 901         }
 902         _ => bug!(
 903             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 904             bin_op,
 905             in_lhs,
 906             in_rhs
 907         ),
 908     };
 909
 910     // TODO: check for overflow
 911     let has_overflow = fx.bcx.ins().iconst(types::I8, 0);
 912
 913     let out_place = CPlace::temp(fx, out_ty);
 914     let out_layout = out_place.layout();
 915     out_place.write_cvalue(fx, CValue::ByValPair(res, has_overflow, out_layout));
 916
 917     out_place.to_cvalue(fx)
 918 }
 919
 920 fn trans_float_binop<'a, 'tcx: 'a>(
 921     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 922     bin_op: BinOp,
 923     lhs: CValue<'tcx>,
 924     rhs: CValue<'tcx>,
 925     ty: Ty<'tcx>,
 926 ) -> CValue<'tcx> {
 927     let res = binop_match! {
 928         fx, bin_op, false, lhs, rhs, ty, "float";
 929         Add (_) fadd;
 930         Sub (_) fsub;
 931         Mul (_) fmul;
 932         Div (_) fdiv;
 933         Rem (_) custom(|| {
 934             assert_eq!(lhs.layout().ty, ty);
 935             assert_eq!(rhs.layout().ty, ty);
 936             match ty.sty {
 937                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
 938                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
 939                 _ => bug!(),
 940             }
 941         });
 942         BitXor (_) bxor;
 943         BitAnd (_) band;
 944         BitOr (_) bor;
 945         Shl (_) bug;
 946         Shr (_) bug;
 947
 948         Eq (_) fcmp(Equal);
 949         Lt (_) fcmp(LessThan);
 950         Le (_) fcmp(LessThanOrEqual);
 951         Ne (_) fcmp(NotEqual);
 952         Ge (_) fcmp(GreaterThanOrEqual);
 953         Gt (_) fcmp(GreaterThan);
 954
 955         Offset (_) bug;
 956     };
 957
 958     res
 959 }
 960
 961 fn trans_char_binop<'a, 'tcx: 'a>(
 962     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 963     bin_op: BinOp,
 964     lhs: CValue<'tcx>,
 965     rhs: CValue<'tcx>,
 966     ty: Ty<'tcx>,
 967 ) -> CValue<'tcx> {
 968     let res = binop_match! {
 969         fx, bin_op, false, lhs, rhs, ty, "char";
 970         Add (_) bug;
 971         Sub (_) bug;
 972         Mul (_) bug;
 973         Div (_) bug;
 974         Rem (_) bug;
 975         BitXor (_) bug;
 976         BitAnd (_) bug;
 977         BitOr (_) bug;
 978         Shl (_) bug;
 979         Shr (_) bug;
 980
 981         Eq (_) icmp(Equal);
 982         Lt (_) icmp(UnsignedLessThan);
 983         Le (_) icmp(UnsignedLessThanOrEqual);
 984         Ne (_) icmp(NotEqual);
 985         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 986         Gt (_) icmp(UnsignedGreaterThan);
 987
 988         Offset (_) bug;
 989     };
 990
 991     res
 992 }
 993
 994 fn trans_ptr_binop<'a, 'tcx: 'a>(
 995     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 996     bin_op: BinOp,
 997     lhs: CValue<'tcx>,
 998     rhs: CValue<'tcx>,
 999     ret_ty: Ty<'tcx>,
1000 ) -> CValue<'tcx> {
1001     match lhs.layout().ty.sty {
1002         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1003             if ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()) {
1004                 binop_match! {
1005                     fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1006                     Add (_) bug;
1007                     Sub (_) bug;
1008                     Mul (_) bug;
1009                     Div (_) bug;
1010                     Rem (_) bug;
1011                     BitXor (_) bug;
1012                     BitAnd (_) bug;
1013                     BitOr (_) bug;
1014                     Shl (_) bug;
1015                     Shr (_) bug;
1016
1017                     Eq (_) icmp(Equal);
1018                     Lt (_) icmp(UnsignedLessThan);
1019                     Le (_) icmp(UnsignedLessThanOrEqual);
1020                     Ne (_) icmp(NotEqual);
1021                     Ge (_) icmp(UnsignedGreaterThanOrEqual);
1022                     Gt (_) icmp(UnsignedGreaterThan);
1023
1024                     Offset (_) iadd;
1025                 }
1026             } else {
1027                 let lhs = lhs.load_value_pair(fx).0;
1028                 let rhs = rhs.load_value_pair(fx).0;
1029                 let res = match bin_op {
1030                     BinOp::Eq => fx.bcx.ins().icmp(IntCC::Equal, lhs, rhs),
1031                     BinOp::Ne => fx.bcx.ins().icmp(IntCC::NotEqual, lhs, rhs),
1032                     _ => unimplemented!(
1033                         "trans_ptr_binop({:?}, <fat ptr>, <fat ptr>) not implemented",
1034                         bin_op
1035                     ),
1036                 };
1037
1038                 assert_eq!(fx.tcx.types.bool, ret_ty);
1039                 let ret_layout = fx.layout_of(ret_ty);
1040                 CValue::ByVal(fx.bcx.ins().bint(types::I8, res), ret_layout)
1041             }
1042         }
1043         _ => bug!("trans_ptr_binop on non ptr"),
1044     }
1045 }
1046
1047 pub fn trans_place<'a, 'tcx: 'a>(
1048     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1049     place: &Place<'tcx>,
1050 ) -> CPlace<'tcx> {
1051     match place {
1052         Place::Local(local) => fx.get_local_place(*local),
1053         Place::Promoted(promoted) => crate::constant::trans_promoted(fx, promoted.0),
1054         Place::Static(static_) => crate::constant::codegen_static_ref(fx, static_),
1055         Place::Projection(projection) => {
1056             let base = trans_place(fx, &projection.base);
1057             match projection.elem {
1058                 ProjectionElem::Deref => base.place_deref(fx),
1059                 ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1060                 ProjectionElem::Index(local) => {
1061                     let index = fx.get_local_place(local).to_cvalue(fx).load_value(fx);
1062                     base.place_index(fx, index)
1063                 }
1064                 ProjectionElem::ConstantIndex {
1065                     offset,
1066                     min_length: _,
1067                     from_end: false,
1068                 } => unimplemented!(
1069                     "projection const index {:?} offset {:?} not from end",
1070                     projection.base,
1071                     offset
1072                 ),
1073                 ProjectionElem::ConstantIndex {
1074                     offset,
1075                     min_length: _,
1076                     from_end: true,
1077                 } => unimplemented!(
1078                     "projection const index {:?} offset {:?} from end",
1079                     projection.base,
1080                     offset
1081                 ),
1082                 ProjectionElem::Subslice { from, to } => unimplemented!(
1083                     "projection subslice {:?} from {} to {}",
1084                     projection.base,
1085                     from,
1086                     to
1087                 ),
1088                 ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1089             }
1090         }
1091     }
1092 }
1093
1094 pub fn trans_operand<'a, 'tcx>(
1095     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1096     operand: &Operand<'tcx>,
1097 ) -> CValue<'tcx> {
1098     match operand {
1099         Operand::Move(place) | Operand::Copy(place) => {
1100             let cplace = trans_place(fx, place);
1101             cplace.to_cvalue(fx)
1102         }
1103         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1104     }
1105 }