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