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     isa: &isa::TargetIsa,
  15     module: &mut Module<impl Backend>,
  16     caches: &mut Caches<'tcx>,
  17     ccx: &mut crate::constant::ConstantCx,
  18     mono_item: MonoItem<'tcx>,
  19 ) {
  20     match mono_item {
  21         MonoItem::Fn(inst) => {
  22             let _inst_guard = PrintOnPanic(|| format!("{:?}", inst));
  23             let _mir_guard = PrintOnPanic(|| {
  24                 match inst.def {
  25                     InstanceDef::Item(_)
  26                     | InstanceDef::DropGlue(_, _)
  27                     | InstanceDef::Virtual(_, _)
  28                         if inst.def_id().krate == LOCAL_CRATE =>
  29                     {
  30                         let mut mir = ::std::io::Cursor::new(Vec::new());
  31                         crate::rustc_mir::util::write_mir_pretty(
  32                             tcx,
  33                             Some(inst.def_id()),
  34                             &mut mir,
  35                         )
  36                         .unwrap();
  37                         String::from_utf8(mir.into_inner()).unwrap()
  38                     }
  39                     InstanceDef::Item(_)
  40                     | InstanceDef::DropGlue(_, _)
  41                     | InstanceDef::Virtual(_, _)
  42                     | InstanceDef::FnPtrShim(_, _)
  43                     | InstanceDef::ClosureOnceShim { .. }
  44                     | InstanceDef::CloneShim(_, _) => {
  45                         // FIXME fix write_mir_pretty for these instances
  46                         format!("{:#?}", tcx.instance_mir(inst.def))
  47                     }
  48                     InstanceDef::Intrinsic(_) => bug!("tried to codegen intrinsic"),
  49                 }
  50             });
  51
  52             trans_fn(tcx, isa, module, ccx, caches, inst);
  53         }
  54         MonoItem::Static(def_id) => {
  55             crate::constant::codegen_static(ccx, def_id);
  56         }
  57         MonoItem::GlobalAsm(node_id) => tcx
  58             .sess
  59             .fatal(&format!("Unimplemented global asm mono item {:?}", node_id)),
  60     }
  61 }
  62
  63 fn trans_fn<'a, 'tcx: 'a>(
  64     tcx: TyCtxt<'a, 'tcx, 'tcx>,
  65     isa: &isa::TargetIsa,
  66     module: &mut Module<impl Backend>,
  67     constants: &mut crate::constant::ConstantCx,
  68     caches: &mut Caches<'tcx>,
  69     instance: Instance<'tcx>,
  70 ) {
  71     // Step 1. Get mir
  72     let mir = tcx.instance_mir(instance.def);
  73
  74     // Step 2. Declare function
  75     let (name, sig) = get_function_name_and_sig(tcx, instance);
  76     let func_id = module
  77         .declare_function(&name, Linkage::Export, &sig)
  78         .unwrap();
  79
  80     // Step 3. Make FunctionBuilder
  81     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
  82     let mut func_ctx = FunctionBuilderContext::new();
  83     let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut func, &mut func_ctx);
  84
  85     // Step 4. Predefine ebb's
  86     let start_ebb = bcx.create_ebb();
  87     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
  88     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
  89         ebb_map.insert(bb, bcx.create_ebb());
  90     }
  91
  92     // Step 5. Make FunctionCx
  93     let mut fx = FunctionCx {
  94         tcx,
  95         isa,
  96         module,
  97         instance,
  98         mir,
  99         bcx,
 100         param_substs: {
 101             assert!(!instance.substs.needs_infer());
 102             instance.substs
 103         },
 104         ebb_map,
 105         local_map: HashMap::new(),
 106         comments: HashMap::new(),
 107         constants,
 108         caches,
 109
 110         top_nop: None,
 111     };
 112
 113     // Step 6. Codegen function
 114     crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
 115     codegen_fn_content(&mut fx);
 116
 117     // Step 7. Write function to file for debugging
 118     let mut writer = crate::pretty_clif::CommentWriter(fx.comments);
 119
 120     let mut cton = String::new();
 121     if cfg!(debug_assertions) {
 122         ::cranelift::codegen::write::decorate_function(&mut writer, &mut cton, &func, None)
 123             .unwrap();
 124         let clif_file_name = format!(
 125             "{}/{}__{}.clif",
 126             concat!(env!("CARGO_MANIFEST_DIR"), "/target/out/clif"),
 127             tcx.crate_name(LOCAL_CRATE),
 128             tcx.symbol_name(instance).as_str(),
 129         );
 130         if let Err(e) = ::std::fs::write(clif_file_name, cton.as_bytes()) {
 131             tcx.sess.warn(&format!("err writing clif file: {:?}", e));
 132         }
 133     }
 134
 135     // Step 8. Verify function
 136     verify_func(tcx, writer, &func);
 137
 138     // Step 9. Define function
 139     // TODO: cranelift doesn't yet support some of the things needed
 140     if should_codegen(tcx.sess) {
 141         caches.context.func = func;
 142         module
 143             .define_function(func_id, &mut caches.context)
 144             .unwrap();
 145         caches.context.clear();
 146     }
 147 }
 148
 149 fn verify_func(tcx: TyCtxt, writer: crate::pretty_clif::CommentWriter, func: &Function) {
 150     let flags = settings::Flags::new(settings::builder());
 151     match ::cranelift::codegen::verify_function(&func, &flags) {
 152         Ok(_) => {}
 153         Err(err) => {
 154             tcx.sess.err(&format!("{:?}", err));
 155             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 156                 &func,
 157                 None,
 158                 Some(Box::new(writer)),
 159                 err,
 160             );
 161             tcx.sess
 162                 .fatal(&format!("cretonne verify error:\n{}", pretty_error));
 163         }
 164     }
 165 }
 166
 167 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 168     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 169         if bb_data.is_cleanup {
 170             // Unwinding after panicking is not supported
 171             continue;
 172         }
 173
 174         let ebb = fx.get_ebb(bb);
 175         fx.bcx.switch_to_block(ebb);
 176
 177         fx.bcx.ins().nop();
 178         for stmt in &bb_data.statements {
 179             trans_stmt(fx, ebb, stmt);
 180         }
 181
 182         let mut terminator_head = "\n".to_string();
 183         bb_data
 184             .terminator()
 185             .kind
 186             .fmt_head(&mut terminator_head)
 187             .unwrap();
 188         let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 189         fx.add_comment(inst, terminator_head);
 190
 191         match &bb_data.terminator().kind {
 192             TerminatorKind::Goto { target } => {
 193                 let ebb = fx.get_ebb(*target);
 194                 fx.bcx.ins().jump(ebb, &[]);
 195             }
 196             TerminatorKind::Return => {
 197                 crate::abi::codegen_return(fx);
 198             }
 199             TerminatorKind::Assert {
 200                 cond,
 201                 expected,
 202                 msg: _,
 203                 target,
 204                 cleanup: _,
 205             } => {
 206                 let cond = trans_operand(fx, cond).load_value(fx);
 207                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 208                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 209                 let target = fx.get_ebb(*target);
 210                 if *expected {
 211                     fx.bcx.ins().brnz(cond, target, &[]);
 212                 } else {
 213                     fx.bcx.ins().brz(cond, target, &[]);
 214                 };
 215                 fx.bcx.ins().trap(TrapCode::User(!0));
 216             }
 217
 218             TerminatorKind::SwitchInt {
 219                 discr,
 220                 switch_ty: _,
 221                 values,
 222                 targets,
 223             } => {
 224                 let discr = trans_operand(fx, discr).load_value(fx);
 225                 let mut switch = ::cranelift::frontend::Switch::new();
 226                 for (i, value) in values.iter().enumerate() {
 227                     let ebb = fx.get_ebb(targets[i]);
 228                     switch.set_entry(*value as u64, ebb);
 229                 }
 230                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 231                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 232             }
 233             TerminatorKind::Call {
 234                 func,
 235                 args,
 236                 destination,
 237                 cleanup: _,
 238                 from_hir_call: _,
 239             } => {
 240                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 241             }
 242             TerminatorKind::Resume | TerminatorKind::Abort | TerminatorKind::Unreachable => {
 243                 fx.bcx.ins().trap(TrapCode::User(!0));
 244             }
 245             TerminatorKind::Yield { .. }
 246             | TerminatorKind::FalseEdges { .. }
 247             | TerminatorKind::FalseUnwind { .. }
 248             | TerminatorKind::DropAndReplace { .. } => {
 249                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 250             }
 251             TerminatorKind::Drop {
 252                 location,
 253                 target,
 254                 unwind: _,
 255             } => {
 256                 let ty = location.ty(fx.mir, fx.tcx).to_ty(fx.tcx);
 257                 let ty = fx.monomorphize(&ty);
 258                 let drop_fn = crate::rustc_mir::monomorphize::resolve_drop_in_place(fx.tcx, ty);
 259
 260                 if let ty::InstanceDef::DropGlue(_, None) = drop_fn.def {
 261                     // we don't actually need to drop anything
 262                 } else {
 263                     let drop_place = trans_place(fx, location);
 264                     let arg_place = CPlace::temp(
 265                         fx,
 266                         fx.tcx.mk_ref(
 267                             &ty::RegionKind::ReErased,
 268                             TypeAndMut {
 269                                 ty,
 270                                 mutbl: crate::rustc::hir::Mutability::MutMutable,
 271                             },
 272                         ),
 273                     );
 274                     drop_place.write_place_ref(fx, arg_place);
 275                     match ty.sty {
 276                         ty::Dynamic(..) => {
 277                             unimplemented!("Drop for trait object");
 278                         }
 279                         _ => {
 280                             let drop_fn_ty = drop_fn.ty(fx.tcx);
 281                             let arg_value = arg_place.to_cvalue(fx);
 282                             crate::abi::codegen_call_inner(
 283                                 fx,
 284                                 None,
 285                                 drop_fn_ty,
 286                                 vec![arg_value],
 287                                 None,
 288                             );
 289                         }
 290                     }
 291                     /*
 292                     let (args1, args2);
 293                     /*let mut args = if let Some(llextra) = place.llextra {
 294                         args2 = [place.llval, llextra];
 295                         &args2[..]
 296                     } else {
 297                         args1 = [place.llval];
 298                         &args1[..]
 299                     };*/
 300                     let (drop_fn, fn_ty) = match ty.sty {
 301                     ty::Dynamic(..) => {
 302                     let fn_ty = drop_fn.ty(bx.cx.tcx);
 303                     let sig = common::ty_fn_sig(bx.cx, fn_ty);
 304                     let sig = bx.tcx().normalize_erasing_late_bound_regions(
 305                     ty::ParamEnv::reveal_all(),
 306                     &sig,
 307                     );
 308                     let fn_ty = FnType::new_vtable(bx.cx, sig, &[]);
 309                     let vtable = args[1];
 310                     args = &args[..1];
 311                     (meth::DESTRUCTOR.get_fn(&bx, vtable, &fn_ty), fn_ty)
 312                     }
 313                     _ => {
 314                     let value = place.to_cvalue(fx);
 315                     (callee::get_fn(bx.cx, drop_fn),
 316                     FnType::of_instance(bx.cx, &drop_fn))
 317                     }
 318                     };
 319                     do_call(self, bx, fn_ty, drop_fn, args,
 320                     Some((ReturnDest::Nothing, target)),
 321                     unwind);*/
 322                 }
 323
 324                 let target_ebb = fx.get_ebb(*target);
 325                 fx.bcx.ins().jump(target_ebb, &[]);
 326             }
 327             TerminatorKind::GeneratorDrop => {
 328                 unimplemented!("terminator GeneratorDrop");
 329             }
 330         };
 331     }
 332
 333     fx.bcx.seal_all_blocks();
 334     fx.bcx.finalize();
 335 }
 336
 337 fn trans_stmt<'a, 'tcx: 'a>(
 338     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 339     cur_ebb: Ebb,
 340     stmt: &Statement<'tcx>,
 341 ) {
 342     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 343
 344     match &stmt.kind {
 345         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 346         _ => {
 347             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 348             fx.add_comment(inst, format!("{:?}", stmt));
 349         }
 350     }
 351
 352     match &stmt.kind {
 353         StatementKind::SetDiscriminant {
 354             place,
 355             variant_index,
 356         } => {
 357             let place = trans_place(fx, place);
 358             let layout = place.layout();
 359             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 360                 return;
 361             }
 362             match layout.variants {
 363                 layout::Variants::Single { index } => {
 364                     assert_eq!(index, *variant_index);
 365                 }
 366                 layout::Variants::Tagged { .. } => {
 367                     let ptr = place.place_field(fx, mir::Field::new(0));
 368                     let to = layout
 369                         .ty
 370                         .ty_adt_def()
 371                         .unwrap()
 372                         .discriminant_for_variant(fx.tcx, *variant_index)
 373                         .val;
 374                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 375                     ptr.write_cvalue(fx, discr);
 376                 }
 377                 layout::Variants::NicheFilling {
 378                     dataful_variant,
 379                     ref niche_variants,
 380                     niche_start,
 381                     ..
 382                 } => {
 383                     if *variant_index != dataful_variant {
 384                         let niche = place.place_field(fx, mir::Field::new(0));
 385                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 386                         let niche_value = ((variant_index - *niche_variants.start()) as u128)
 387                             .wrapping_add(niche_start);
 388                         // FIXME(eddyb) Check the actual primitive type here.
 389                         let niche_llval = if niche_value == 0 {
 390                             CValue::const_val(fx, niche.layout().ty, 0)
 391                         } else {
 392                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 393                         };
 394                         niche.write_cvalue(fx, niche_llval);
 395                     }
 396                 }
 397             }
 398         }
 399         StatementKind::Assign(to_place, rval) => {
 400             let lval = trans_place(fx, to_place);
 401             let dest_layout = lval.layout();
 402             match &**rval {
 403                 Rvalue::Use(operand) => {
 404                     let val = trans_operand(fx, operand);
 405                     lval.write_cvalue(fx, val);
 406                 }
 407                 Rvalue::Ref(_, _, place) => {
 408                     let place = trans_place(fx, place);
 409                     place.write_place_ref(fx, lval);
 410                 }
 411                 Rvalue::BinaryOp(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::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 418                         ty::Uint(_) => {
 419                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 420                         }
 421                         ty::Int(_) => {
 422                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 423                         }
 424                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 425                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 426                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 427                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 428                     };
 429                     lval.write_cvalue(fx, res);
 430                 }
 431                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 432                     let ty = fx.monomorphize(&lhs.ty(&fx.mir.local_decls, fx.tcx));
 433                     let lhs = trans_operand(fx, lhs);
 434                     let rhs = trans_operand(fx, rhs);
 435
 436                     let res = match ty.sty {
 437                         ty::Uint(_) => {
 438                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 439                         }
 440                         ty::Int(_) => {
 441                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 442                         }
 443                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 444                     };
 445                     lval.write_cvalue(fx, res);
 446                 }
 447                 Rvalue::UnaryOp(un_op, operand) => {
 448                     let operand = trans_operand(fx, operand);
 449                     let layout = operand.layout();
 450                     let val = operand.load_value(fx);
 451                     let res = match un_op {
 452                         UnOp::Not => {
 453                             match layout.ty.sty {
 454                                 ty::Bool => {
 455                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 456                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 457                                     fx.bcx.ins().bint(types::I8, res)
 458                                 }
 459                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 460                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 461                             }
 462                         }
 463                         UnOp::Neg => match layout.ty.sty {
 464                             ty::Int(_) => {
 465                                 let clif_ty = fx.cton_type(layout.ty).unwrap();
 466                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 467                                 fx.bcx.ins().isub(zero, val)
 468                             }
 469                             ty::Float(_) => fx.bcx.ins().fneg(val),
 470                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 471                         },
 472                     };
 473                     lval.write_cvalue(fx, CValue::ByVal(res, layout));
 474                 }
 475                 Rvalue::Cast(CastKind::ReifyFnPointer, operand, ty) => {
 476                     let operand = trans_operand(fx, operand);
 477                     let layout = fx.layout_of(ty);
 478                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 479                 }
 480                 Rvalue::Cast(CastKind::UnsafeFnPointer, operand, ty) => {
 481                     let operand = trans_operand(fx, operand);
 482                     let layout = fx.layout_of(ty);
 483                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 484                 }
 485                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 486                     let operand = trans_operand(fx, operand);
 487                     let from_ty = operand.layout().ty;
 488                     match (&from_ty.sty, &to_ty.sty) {
 489                         (ty::Ref(..), ty::Ref(..))
 490                         | (ty::Ref(..), ty::RawPtr(..))
 491                         | (ty::RawPtr(..), ty::Ref(..))
 492                         | (ty::RawPtr(..), ty::RawPtr(..)) => {
 493                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 494                         }
 495                         (ty::RawPtr(..), ty::Uint(_)) | (ty::FnPtr(..), ty::Uint(_))
 496                             if to_ty.sty == fx.tcx.types.usize.sty =>
 497                         {
 498                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 499                         }
 500                         (ty::Uint(_), ty::RawPtr(..)) if from_ty.sty == fx.tcx.types.usize.sty => {
 501                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 502                         }
 503                         (ty::Char, ty::Uint(_))
 504                         | (ty::Uint(_), ty::Char)
 505                         | (ty::Uint(_), ty::Int(_))
 506                         | (ty::Uint(_), ty::Uint(_)) => {
 507                             let from = operand.load_value(fx);
 508                             let res = crate::common::cton_intcast(
 509                                 fx,
 510                                 from,
 511                                 fx.cton_type(to_ty).unwrap(),
 512                                 false,
 513                             );
 514                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 515                         }
 516                         (ty::Int(_), ty::Int(_)) | (ty::Int(_), ty::Uint(_)) => {
 517                             let from = operand.load_value(fx);
 518                             let res = crate::common::cton_intcast(
 519                                 fx,
 520                                 from,
 521                                 fx.cton_type(to_ty).unwrap(),
 522                                 true,
 523                             );
 524                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 525                         }
 526                         (ty::Float(from_flt), ty::Float(to_flt)) => {
 527                             let from = operand.load_value(fx);
 528                             let res = match (from_flt, to_flt) {
 529                                 (FloatTy::F32, FloatTy::F64) => {
 530                                     fx.bcx.ins().fpromote(types::F64, from)
 531                                 }
 532                                 (FloatTy::F64, FloatTy::F32) => {
 533                                     fx.bcx.ins().fdemote(types::F32, from)
 534                                 }
 535                                 _ => from,
 536                             };
 537                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 538                         }
 539                         (ty::Int(_), ty::Float(_)) => {
 540                             let from_ty = fx.cton_type(from_ty).unwrap();
 541                             let from = operand.load_value(fx);
 542                             // FIXME missing encoding for fcvt_from_sint.f32.i8
 543                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 544                                 fx.bcx.ins().sextend(types::I32, from)
 545                             } else {
 546                                 from
 547                             };
 548                             let f_type = fx.cton_type(to_ty).unwrap();
 549                             let res = fx.bcx.ins().fcvt_from_sint(f_type, from);
 550                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 551                         }
 552                         (ty::Uint(_), ty::Float(_)) => {
 553                             let from_ty = fx.cton_type(from_ty).unwrap();
 554                             let from = operand.load_value(fx);
 555                             // FIXME missing encoding for fcvt_from_uint.f32.i8
 556                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 557                                 fx.bcx.ins().uextend(types::I32, from)
 558                             } else {
 559                                 from
 560                             };
 561                             let f_type = fx.cton_type(to_ty).unwrap();
 562                             let res = fx.bcx.ins().fcvt_from_uint(f_type, from);
 563                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 564                         }
 565                         (ty::Bool, ty::Uint(_)) | (ty::Bool, ty::Int(_)) => {
 566                             let to_ty = fx.cton_type(to_ty).unwrap();
 567                             let from = operand.load_value(fx);
 568                             let res = if to_ty != types::I8 {
 569                                 fx.bcx.ins().uextend(to_ty, from)
 570                             } else {
 571                                 from
 572                             };
 573                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 574                         }
 575                         _ => unimpl!("rval misc {:?} {:?}", from_ty, to_ty),
 576                     }
 577                 }
 578                 Rvalue::Cast(CastKind::ClosureFnPointer, operand, ty) => {
 579                     unimplemented!("rval closure_fn_ptr {:?} {:?}", operand, ty)
 580                 }
 581                 Rvalue::Cast(CastKind::Unsize, operand, _ty) => {
 582                     let operand = trans_operand(fx, operand);
 583                     operand.unsize_value(fx, lval);
 584                 }
 585                 Rvalue::Discriminant(place) => {
 586                     let place = trans_place(fx, place).to_cvalue(fx);
 587                     let discr = trans_get_discriminant(fx, place, dest_layout);
 588                     lval.write_cvalue(fx, discr);
 589                 }
 590                 Rvalue::Repeat(operand, times) => {
 591                     let operand = trans_operand(fx, operand);
 592                     for i in 0..*times {
 593                         let index = fx.bcx.ins().iconst(fx.module.pointer_type(), i as i64);
 594                         let to = lval.place_index(fx, index);
 595                         to.write_cvalue(fx, operand);
 596                     }
 597                 }
 598                 Rvalue::Len(place) => {
 599                     let place = trans_place(fx, place);
 600                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 601                     let len = match place.layout().ty.sty {
 602                         ty::Array(_elem_ty, len) => {
 603                             let len = crate::constant::force_eval_const(fx, len)
 604                                 .unwrap_usize(fx.tcx) as i64;
 605                             fx.bcx.ins().iconst(fx.module.pointer_type(), len)
 606                         }
 607                         ty::Slice(_elem_ty) => match place {
 608                             CPlace::Addr(_, size, _) => size.unwrap(),
 609                             CPlace::Var(_, _) => unreachable!(),
 610                         },
 611                         _ => bug!("Rvalue::Len({:?})", place),
 612                     };
 613                     lval.write_cvalue(fx, CValue::ByVal(len, usize_layout));
 614                 }
 615                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 616                     use crate::rustc::middle::lang_items::ExchangeMallocFnLangItem;
 617
 618                     let usize_type = fx.cton_type(fx.tcx.types.usize).unwrap();
 619                     let (size, align) = fx.layout_of(content_ty).size_and_align();
 620                     let llsize = fx.bcx.ins().iconst(usize_type, size.bytes() as i64);
 621                     let llalign = fx.bcx.ins().iconst(usize_type, align.abi() as i64);
 622                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 623
 624                     // Allocate space:
 625                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 626                         Ok(id) => id,
 627                         Err(s) => {
 628                             fx.tcx
 629                                 .sess
 630                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 631                         }
 632                     };
 633                     let instance = ty::Instance::mono(fx.tcx, def_id);
 634                     let func_ref = fx.get_function_ref(instance);
 635                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 636                     let ptr = fx.bcx.inst_results(call)[0];
 637                     lval.write_cvalue(fx, CValue::ByVal(ptr, box_layout));
 638                 }
 639                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 640                     assert!(
 641                         lval.layout()
 642                             .ty
 643                             .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
 644                     );
 645                     let ty_size = fx.layout_of(ty).size.bytes();
 646                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 647                     lval.write_cvalue(fx, val);
 648                 }
 649                 Rvalue::Aggregate(kind, operands) => match **kind {
 650                     AggregateKind::Array(_ty) => {
 651                         for (i, operand) in operands.into_iter().enumerate() {
 652                             let operand = trans_operand(fx, operand);
 653                             let index = fx.bcx.ins().iconst(fx.module.pointer_type(), i as i64);
 654                             let to = lval.place_index(fx, index);
 655                             to.write_cvalue(fx, operand);
 656                         }
 657                     }
 658                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 659                 },
 660             }
 661         }
 662         StatementKind::StorageLive(_)
 663         | StatementKind::StorageDead(_)
 664         | StatementKind::Nop
 665         | StatementKind::FakeRead(..)
 666         | StatementKind::Validate(_, _)
 667         | StatementKind::EndRegion(_)
 668         | StatementKind::AscribeUserType(..) => {}
 669
 670         StatementKind::InlineAsm { .. } => unimpl!("Inline assembly is not supported"),
 671     }
 672 }
 673
 674 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 675     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 676     value: CValue<'tcx>,
 677     dest_layout: TyLayout<'tcx>,
 678 ) -> CValue<'tcx> {
 679     let layout = value.layout();
 680
 681     if layout.abi == layout::Abi::Uninhabited {
 682         fx.bcx.ins().trap(TrapCode::User(!0));
 683     }
 684     match layout.variants {
 685         layout::Variants::Single { index } => {
 686             let discr_val = layout.ty.ty_adt_def().map_or(index as u128, |def| {
 687                 def.discriminant_for_variant(fx.tcx, index).val
 688             });
 689             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 690         }
 691         layout::Variants::Tagged { .. } | layout::Variants::NicheFilling { .. } => {}
 692     }
 693
 694     let discr = value.value_field(fx, mir::Field::new(0));
 695     let discr_ty = discr.layout().ty;
 696     let lldiscr = discr.load_value(fx);
 697     match layout.variants {
 698         layout::Variants::Single { .. } => bug!(),
 699         layout::Variants::Tagged { ref tag, .. } => {
 700             let signed = match tag.value {
 701                 layout::Int(_, signed) => signed,
 702                 _ => false,
 703             };
 704             let val = cton_intcast(fx, lldiscr, fx.cton_type(dest_layout.ty).unwrap(), signed);
 705             return CValue::ByVal(val, dest_layout);
 706         }
 707         layout::Variants::NicheFilling {
 708             dataful_variant,
 709             ref niche_variants,
 710             niche_start,
 711             ..
 712         } => {
 713             let niche_llty = fx.cton_type(discr_ty).unwrap();
 714             let dest_cton_ty = fx.cton_type(dest_layout.ty).unwrap();
 715             if niche_variants.start() == niche_variants.end() {
 716                 let b = fx
 717                     .bcx
 718                     .ins()
 719                     .icmp_imm(IntCC::Equal, lldiscr, niche_start as u64 as i64);
 720                 let if_true = fx
 721                     .bcx
 722                     .ins()
 723                     .iconst(dest_cton_ty, *niche_variants.start() as u64 as i64);
 724                 let if_false = fx
 725                     .bcx
 726                     .ins()
 727                     .iconst(dest_cton_ty, dataful_variant as u64 as i64);
 728                 let val = fx.bcx.ins().select(b, if_true, if_false);
 729                 return CValue::ByVal(val, dest_layout);
 730             } else {
 731                 // Rebase from niche values to discriminant values.
 732                 let delta = niche_start.wrapping_sub(*niche_variants.start() as u128);
 733                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 734                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 735                 let b = fx.bcx.ins().icmp_imm(
 736                     IntCC::UnsignedLessThanOrEqual,
 737                     lldiscr,
 738                     *niche_variants.end() as u64 as i64,
 739                 );
 740                 let if_true =
 741                     cton_intcast(fx, lldiscr, fx.cton_type(dest_layout.ty).unwrap(), false);
 742                 let if_false = fx
 743                     .bcx
 744                     .ins()
 745                     .iconst(dest_cton_ty, dataful_variant as u64 as i64);
 746                 let val = fx.bcx.ins().select(b, if_true, if_false);
 747                 return CValue::ByVal(val, dest_layout);
 748             }
 749         }
 750     }
 751 }
 752
 753 macro_rules! binop_match {
 754     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 755         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 756     };
 757     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 758         assert_eq!($fx.tcx.types.bool, $ret_ty);
 759         let ret_layout = $fx.layout_of($ret_ty);
 760
 761         // TODO HACK no encoding for icmp.i8
 762         use crate::common::cton_intcast;
 763         let (lhs, rhs) = (
 764             cton_intcast($fx, $lhs, types::I64, $signed),
 765             cton_intcast($fx, $rhs, types::I64, $signed),
 766         );
 767         let b = $fx.bcx.ins().icmp(IntCC::$cc, lhs, rhs);
 768
 769         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 770     }};
 771     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 772         assert_eq!($fx.tcx.types.bool, $ret_ty);
 773         let ret_layout = $fx.layout_of($ret_ty);
 774         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 775         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 776     }};
 777     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 778         $body
 779     }};
 780     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 781         let ret_layout = $fx.layout_of($ret_ty);
 782         CValue::ByVal($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 783     }};
 784     (
 785         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 786         $(
 787             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 788         )*
 789     ) => {{
 790         let lhs = $lhs.load_value($fx);
 791         let rhs = $rhs.load_value($fx);
 792         match ($bin_op, $signed) {
 793             $(
 794                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 795             )*
 796         }
 797     }}
 798 }
 799
 800 fn trans_bool_binop<'a, 'tcx: 'a>(
 801     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 802     bin_op: BinOp,
 803     lhs: CValue<'tcx>,
 804     rhs: CValue<'tcx>,
 805     ty: Ty<'tcx>,
 806 ) -> CValue<'tcx> {
 807     let res = binop_match! {
 808         fx, bin_op, false, lhs, rhs, ty, "bool";
 809         Add (_) bug;
 810         Sub (_) bug;
 811         Mul (_) bug;
 812         Div (_) bug;
 813         Rem (_) bug;
 814         BitXor (_) bxor;
 815         BitAnd (_) band;
 816         BitOr (_) bor;
 817         Shl (_) bug;
 818         Shr (_) bug;
 819
 820         Eq (_) icmp(Equal);
 821         Lt (_) icmp(UnsignedLessThan);
 822         Le (_) icmp(UnsignedLessThanOrEqual);
 823         Ne (_) icmp(NotEqual);
 824         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 825         Gt (_) icmp(UnsignedGreaterThan);
 826
 827         Offset (_) bug;
 828     };
 829
 830     res
 831 }
 832
 833 pub fn trans_int_binop<'a, 'tcx: 'a>(
 834     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 835     bin_op: BinOp,
 836     lhs: CValue<'tcx>,
 837     rhs: CValue<'tcx>,
 838     out_ty: Ty<'tcx>,
 839     signed: bool,
 840 ) -> CValue<'tcx> {
 841     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 842         assert_eq!(
 843             lhs.layout().ty,
 844             rhs.layout().ty,
 845             "int binop requires lhs and rhs of same type"
 846         );
 847     }
 848     binop_match! {
 849         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 850         Add (_) iadd;
 851         Sub (_) isub;
 852         Mul (_) imul;
 853         Div (false) udiv;
 854         Div (true) sdiv;
 855         Rem (false) urem;
 856         Rem (true) srem;
 857         BitXor (_) bxor;
 858         BitAnd (_) band;
 859         BitOr (_) bor;
 860         Shl (_) ishl;
 861         Shr (false) ushr;
 862         Shr (true) sshr;
 863
 864         Eq (_) icmp(Equal);
 865         Lt (false) icmp(UnsignedLessThan);
 866         Lt (true) icmp(SignedLessThan);
 867         Le (false) icmp(UnsignedLessThanOrEqual);
 868         Le (true) icmp(SignedLessThanOrEqual);
 869         Ne (_) icmp(NotEqual);
 870         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 871         Ge (true) icmp(SignedGreaterThanOrEqual);
 872         Gt (false) icmp(UnsignedGreaterThan);
 873         Gt (true) icmp(SignedGreaterThan);
 874
 875         Offset (_) bug;
 876     }
 877 }
 878
 879 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 880     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 881     bin_op: BinOp,
 882     in_lhs: CValue<'tcx>,
 883     in_rhs: CValue<'tcx>,
 884     out_ty: Ty<'tcx>,
 885     signed: bool,
 886 ) -> CValue<'tcx> {
 887     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 888         assert_eq!(
 889             in_lhs.layout().ty,
 890             in_rhs.layout().ty,
 891             "checked int binop requires lhs and rhs of same type"
 892         );
 893     }
 894
 895     let lhs = in_lhs.load_value(fx);
 896     let rhs = in_rhs.load_value(fx);
 897     let res = match bin_op {
 898         BinOp::Add => fx.bcx.ins().iadd(lhs, rhs),
 899         BinOp::Sub => fx.bcx.ins().isub(lhs, rhs),
 900         BinOp::Mul => fx.bcx.ins().imul(lhs, rhs),
 901         BinOp::Shl => fx.bcx.ins().ishl(lhs, rhs),
 902         BinOp::Shr => {
 903             if !signed {
 904                 fx.bcx.ins().ushr(lhs, rhs)
 905             } else {
 906                 fx.bcx.ins().sshr(lhs, rhs)
 907             }
 908         }
 909         _ => bug!(
 910             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 911             bin_op,
 912             in_lhs,
 913             in_rhs
 914         ),
 915     };
 916
 917     // TODO: check for overflow
 918     let has_overflow = fx.bcx.ins().iconst(types::I8, 0);
 919
 920     let out_place = CPlace::temp(fx, out_ty);
 921     let out_layout = out_place.layout();
 922     out_place.write_cvalue(fx, CValue::ByValPair(res, has_overflow, out_layout));
 923
 924     out_place.to_cvalue(fx)
 925 }
 926
 927 fn trans_float_binop<'a, 'tcx: 'a>(
 928     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 929     bin_op: BinOp,
 930     lhs: CValue<'tcx>,
 931     rhs: CValue<'tcx>,
 932     ty: Ty<'tcx>,
 933 ) -> CValue<'tcx> {
 934     let res = binop_match! {
 935         fx, bin_op, false, lhs, rhs, ty, "float";
 936         Add (_) fadd;
 937         Sub (_) fsub;
 938         Mul (_) fmul;
 939         Div (_) fdiv;
 940         Rem (_) custom(|| {
 941             assert_eq!(lhs.layout().ty, ty);
 942             assert_eq!(rhs.layout().ty, ty);
 943             match ty.sty {
 944                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
 945                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
 946                 _ => bug!(),
 947             }
 948         });
 949         BitXor (_) bxor;
 950         BitAnd (_) band;
 951         BitOr (_) bor;
 952         Shl (_) bug;
 953         Shr (_) bug;
 954
 955         Eq (_) fcmp(Equal);
 956         Lt (_) fcmp(LessThan);
 957         Le (_) fcmp(LessThanOrEqual);
 958         Ne (_) fcmp(NotEqual);
 959         Ge (_) fcmp(GreaterThanOrEqual);
 960         Gt (_) fcmp(GreaterThan);
 961
 962         Offset (_) bug;
 963     };
 964
 965     res
 966 }
 967
 968 fn trans_char_binop<'a, 'tcx: 'a>(
 969     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 970     bin_op: BinOp,
 971     lhs: CValue<'tcx>,
 972     rhs: CValue<'tcx>,
 973     ty: Ty<'tcx>,
 974 ) -> CValue<'tcx> {
 975     let res = binop_match! {
 976         fx, bin_op, false, lhs, rhs, ty, "char";
 977         Add (_) bug;
 978         Sub (_) bug;
 979         Mul (_) bug;
 980         Div (_) bug;
 981         Rem (_) bug;
 982         BitXor (_) bug;
 983         BitAnd (_) bug;
 984         BitOr (_) bug;
 985         Shl (_) bug;
 986         Shr (_) bug;
 987
 988         Eq (_) icmp(Equal);
 989         Lt (_) icmp(UnsignedLessThan);
 990         Le (_) icmp(UnsignedLessThanOrEqual);
 991         Ne (_) icmp(NotEqual);
 992         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 993         Gt (_) icmp(UnsignedGreaterThan);
 994
 995         Offset (_) bug;
 996     };
 997
 998     res
 999 }
1000
1001 fn trans_ptr_binop<'a, 'tcx: 'a>(
1002     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1003     bin_op: BinOp,
1004     lhs: CValue<'tcx>,
1005     rhs: CValue<'tcx>,
1006     ret_ty: Ty<'tcx>,
1007 ) -> CValue<'tcx> {
1008     match lhs.layout().ty.sty {
1009         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1010             if ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()) {
1011                 binop_match! {
1012                     fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1013                     Add (_) bug;
1014                     Sub (_) bug;
1015                     Mul (_) bug;
1016                     Div (_) bug;
1017                     Rem (_) bug;
1018                     BitXor (_) bug;
1019                     BitAnd (_) bug;
1020                     BitOr (_) bug;
1021                     Shl (_) bug;
1022                     Shr (_) bug;
1023
1024                     Eq (_) icmp(Equal);
1025                     Lt (_) icmp(UnsignedLessThan);
1026                     Le (_) icmp(UnsignedLessThanOrEqual);
1027                     Ne (_) icmp(NotEqual);
1028                     Ge (_) icmp(UnsignedGreaterThanOrEqual);
1029                     Gt (_) icmp(UnsignedGreaterThan);
1030
1031                     Offset (_) iadd;
1032                 }
1033             } else {
1034                 let lhs = lhs.load_value_pair(fx).0;
1035                 let rhs = rhs.load_value_pair(fx).0;
1036                 let res = match bin_op {
1037                     BinOp::Eq => fx.bcx.ins().icmp(IntCC::Equal, lhs, rhs),
1038                     BinOp::Ne => fx.bcx.ins().icmp(IntCC::NotEqual, lhs, rhs),
1039                     _ => unimplemented!(
1040                         "trans_ptr_binop({:?}, <fat ptr>, <fat ptr>) not implemented",
1041                         bin_op
1042                     ),
1043                 };
1044
1045                 assert_eq!(fx.tcx.types.bool, ret_ty);
1046                 let ret_layout = fx.layout_of(ret_ty);
1047                 CValue::ByVal(fx.bcx.ins().bint(types::I8, res), ret_layout)
1048             }
1049         }
1050         _ => bug!("trans_ptr_binop on non ptr"),
1051     }
1052 }
1053
1054 pub fn trans_place<'a, 'tcx: 'a>(
1055     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1056     place: &Place<'tcx>,
1057 ) -> CPlace<'tcx> {
1058     match place {
1059         Place::Local(local) => fx.get_local_place(*local),
1060         Place::Promoted(promoted) => crate::constant::trans_promoted(fx, promoted.0),
1061         Place::Static(static_) => crate::constant::codegen_static_ref(fx, static_),
1062         Place::Projection(projection) => {
1063             let base = trans_place(fx, &projection.base);
1064             match projection.elem {
1065                 ProjectionElem::Deref => base.place_deref(fx),
1066                 ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1067                 ProjectionElem::Index(local) => {
1068                     let index = fx.get_local_place(local).to_cvalue(fx).load_value(fx);
1069                     base.place_index(fx, index)
1070                 }
1071                 ProjectionElem::ConstantIndex {
1072                     offset,
1073                     min_length: _,
1074                     from_end: false,
1075                 } => unimplemented!(
1076                     "projection const index {:?} offset {:?} not from end",
1077                     projection.base,
1078                     offset
1079                 ),
1080                 ProjectionElem::ConstantIndex {
1081                     offset,
1082                     min_length: _,
1083                     from_end: true,
1084                 } => unimplemented!(
1085                     "projection const index {:?} offset {:?} from end",
1086                     projection.base,
1087                     offset
1088                 ),
1089                 ProjectionElem::Subslice { from, to } => unimplemented!(
1090                     "projection subslice {:?} from {} to {}",
1091                     projection.base,
1092                     from,
1093                     to
1094                 ),
1095                 ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1096             }
1097         }
1098     }
1099 }
1100
1101 pub fn trans_operand<'a, 'tcx>(
1102     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1103     operand: &Operand<'tcx>,
1104 ) -> CValue<'tcx> {
1105     match operand {
1106         Operand::Move(place) | Operand::Copy(place) => {
1107             let cplace = trans_place(fx, place);
1108             cplace.to_cvalue(fx)
1109         }
1110         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1111     }
1112 }