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, 'clif, 'tcx: 'a, B: Backend + 'static>(
  13     cx: &mut crate::CodegenCx<'a, 'clif, 'tcx, B>,
  14     mono_item: MonoItem<'tcx>,
  15     linkage: Linkage,
  16 ) {
  17     let tcx = cx.tcx;
  18     match mono_item {
  19         MonoItem::Fn(inst) => {
  20             let _inst_guard =
  21                 PrintOnPanic(|| format!("{:?} {}", inst, tcx.symbol_name(inst).as_str()));
  22             debug_assert!(!inst.substs.needs_infer());
  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                     _ => {
  40                         // FIXME fix write_mir_pretty for these instances
  41                         format!("{:#?}", tcx.instance_mir(inst.def))
  42                     }
  43                 }
  44             });
  45
  46             trans_fn(cx, inst, linkage);
  47         }
  48         MonoItem::Static(def_id) => {
  49             crate::constant::codegen_static(&mut cx.ccx, def_id);
  50         }
  51         MonoItem::GlobalAsm(node_id) => tcx
  52             .sess
  53             .fatal(&format!("Unimplemented global asm mono item {:?}", node_id)),
  54     }
  55 }
  56
  57 fn trans_fn<'a, 'clif, 'tcx: 'a, B: Backend + 'static>(
  58     cx: &mut crate::CodegenCx<'a, 'clif, 'tcx, B>,
  59     instance: Instance<'tcx>,
  60     linkage: Linkage,
  61 ) {
  62     let tcx = cx.tcx;
  63
  64     // Step 1. Get mir
  65     let mir = tcx.instance_mir(instance.def);
  66
  67     // Step 2. Check fn sig for u128 and i128 and replace those functions with a trap.
  68     {
  69         // FIXME implement u128 and i128 support
  70
  71         // Step 2a. Check sig for u128 and i128
  72         let fn_sig = tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), &instance.fn_sig(tcx));
  73
  74         struct UI128Visitor<'a, 'tcx: 'a>(TyCtxt<'a, 'tcx, 'tcx>, bool);
  75
  76         impl<'a, 'tcx: 'a> rustc::ty::fold::TypeVisitor<'tcx> for UI128Visitor<'a, 'tcx> {
  77             fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
  78                 if t.sty == self.0.types.u128.sty || t.sty == self.0.types.i128.sty {
  79                     self.1 = true;
  80                     return false; // stop visiting
  81                 }
  82
  83                 t.super_visit_with(self)
  84             }
  85         }
  86
  87         let mut visitor = UI128Visitor(tcx, false);
  88         fn_sig.visit_with(&mut visitor);
  89
  90         // Step 2b. If found replace function with a trap.
  91         if visitor.1 {
  92             tcx.sess.warn("u128 and i128 are not yet supported. \
  93             Functions using these as args will be replaced with a trap.");
  94
  95             // Step 2b1. Declare function with fake signature
  96             let sig = Signature {
  97                 params: vec![AbiParam::new(types::INVALID)],
  98                 returns: vec![],
  99                 call_conv: CallConv::Fast,
 100             };
 101             let name = tcx.symbol_name(instance).as_str();
 102             let func_id = cx.module.declare_function(&*name, linkage, &sig).unwrap();
 103
 104             // Step 2b2. Create trapping function
 105             let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
 106             let mut func_ctx = FunctionBuilderContext::new();
 107             let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
 108             let start_ebb = bcx.create_ebb();
 109             bcx.append_ebb_params_for_function_params(start_ebb);
 110             bcx.switch_to_block(start_ebb);
 111             crate::trap::trap_unreachable(&mut bcx);
 112             bcx.seal_all_blocks();
 113             bcx.finalize();
 114
 115             // Step 2b3. Define function
 116             cx.caches.context.func = func;
 117             cx.module
 118                 .define_function(func_id, &mut cx.caches.context)
 119                 .unwrap();
 120             cx.caches.context.clear();
 121             return;
 122         }
 123     }
 124
 125     // Step 3. Declare function
 126     let (name, sig) = get_function_name_and_sig(tcx, instance, false);
 127     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
 128     let mut debug_context = cx
 129         .debug_context
 130         .as_mut()
 131         .map(|debug_context| FunctionDebugContext::new(tcx, debug_context, mir, &name, &sig));
 132
 133     // Step 4. Make FunctionBuilder
 134     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
 135     let mut func_ctx = FunctionBuilderContext::new();
 136     let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
 137
 138     // Step 5. Predefine ebb's
 139     let start_ebb = bcx.create_ebb();
 140     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
 141     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
 142         ebb_map.insert(bb, bcx.create_ebb());
 143     }
 144
 145     // Step 6. Make FunctionCx
 146     let pointer_type = cx.module.target_config().pointer_type();
 147     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
 148
 149     let mut fx = FunctionCx {
 150         tcx,
 151         module: cx.module,
 152         pointer_type,
 153
 154         instance,
 155         mir,
 156
 157         bcx,
 158         ebb_map,
 159         local_map: HashMap::new(),
 160
 161         clif_comments,
 162         constants: &mut cx.ccx,
 163         caches: &mut cx.caches,
 164         source_info_set: indexmap::IndexSet::new(),
 165     };
 166
 167     // Step 7. Codegen function
 168     with_unimpl_span(fx.mir.span, || {
 169         crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
 170         codegen_fn_content(&mut fx);
 171     });
 172     let source_info_set = fx.source_info_set.clone();
 173
 174     // Step 8. Write function to file for debugging
 175     #[cfg(debug_assertions)]
 176     fx.write_clif_file();
 177
 178     // Step 9. Verify function
 179     verify_func(tcx, fx.clif_comments, &func);
 180
 181     // Step 10. Define function
 182     cx.caches.context.func = func;
 183     cx.module
 184         .define_function(func_id, &mut cx.caches.context)
 185         .unwrap();
 186
 187     // Step 11. Define debuginfo for function
 188     let context = &cx.caches.context;
 189     let isa = cx.module.isa();
 190     debug_context
 191         .as_mut()
 192         .map(|x| x.define(tcx, context, isa, &source_info_set));
 193
 194     // Step 12. Clear context to make it usable for the next function
 195     cx.caches.context.clear();
 196 }
 197
 198 fn verify_func(tcx: TyCtxt, writer: crate::pretty_clif::CommentWriter, func: &Function) {
 199     let flags = settings::Flags::new(settings::builder());
 200     match ::cranelift::codegen::verify_function(&func, &flags) {
 201         Ok(_) => {}
 202         Err(err) => {
 203             tcx.sess.err(&format!("{:?}", err));
 204             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 205                 &func,
 206                 None,
 207                 Some(Box::new(&writer)),
 208                 err,
 209             );
 210             tcx.sess
 211                 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
 212         }
 213     }
 214 }
 215
 216 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 217     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 218         if bb_data.is_cleanup {
 219             // Unwinding after panicking is not supported
 220             continue;
 221         }
 222
 223         let ebb = fx.get_ebb(bb);
 224         fx.bcx.switch_to_block(ebb);
 225
 226         fx.bcx.ins().nop();
 227         for stmt in &bb_data.statements {
 228             fx.set_debug_loc(stmt.source_info);
 229             trans_stmt(fx, ebb, stmt);
 230         }
 231
 232         #[cfg(debug_assertions)]
 233         {
 234             let mut terminator_head = "\n".to_string();
 235             bb_data
 236                 .terminator()
 237                 .kind
 238                 .fmt_head(&mut terminator_head)
 239                 .unwrap();
 240             let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 241             fx.add_comment(inst, terminator_head);
 242         }
 243
 244         fx.set_debug_loc(bb_data.terminator().source_info);
 245
 246         match &bb_data.terminator().kind {
 247             TerminatorKind::Goto { target } => {
 248                 let ebb = fx.get_ebb(*target);
 249                 fx.bcx.ins().jump(ebb, &[]);
 250             }
 251             TerminatorKind::Return => {
 252                 crate::abi::codegen_return(fx);
 253             }
 254             TerminatorKind::Assert {
 255                 cond,
 256                 expected,
 257                 msg: _,
 258                 target,
 259                 cleanup: _,
 260             } => {
 261                 let cond = trans_operand(fx, cond).load_scalar(fx);
 262                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 263                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 264                 let target = fx.get_ebb(*target);
 265                 if *expected {
 266                     fx.bcx.ins().brnz(cond, target, &[]);
 267                 } else {
 268                     fx.bcx.ins().brz(cond, target, &[]);
 269                 };
 270                 trap_panic(&mut fx.bcx);
 271             }
 272
 273             TerminatorKind::SwitchInt {
 274                 discr,
 275                 switch_ty: _,
 276                 values,
 277                 targets,
 278             } => {
 279                 let discr = trans_operand(fx, discr).load_scalar(fx);
 280                 let mut switch = ::cranelift::frontend::Switch::new();
 281                 for (i, value) in values.iter().enumerate() {
 282                     let ebb = fx.get_ebb(targets[i]);
 283                     switch.set_entry(*value as u64, ebb);
 284                 }
 285                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 286                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 287             }
 288             TerminatorKind::Call {
 289                 func,
 290                 args,
 291                 destination,
 292                 cleanup: _,
 293                 from_hir_call: _,
 294             } => {
 295                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 296             }
 297             TerminatorKind::Resume | TerminatorKind::Abort | TerminatorKind::Unreachable => {
 298                 trap_unreachable(&mut fx.bcx);
 299             }
 300             TerminatorKind::Yield { .. }
 301             | TerminatorKind::FalseEdges { .. }
 302             | TerminatorKind::FalseUnwind { .. }
 303             | TerminatorKind::DropAndReplace { .. }
 304             | TerminatorKind::GeneratorDrop => {
 305                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 306             }
 307             TerminatorKind::Drop {
 308                 location,
 309                 target,
 310                 unwind: _,
 311             } => {
 312                 let ty = location.ty(fx.mir, fx.tcx).to_ty(fx.tcx);
 313                 let ty = fx.monomorphize(&ty);
 314                 let drop_fn = crate::rustc_mir::monomorphize::resolve_drop_in_place(fx.tcx, ty);
 315
 316                 if let ty::InstanceDef::DropGlue(_, None) = drop_fn.def {
 317                     // we don't actually need to drop anything
 318                 } else {
 319                     let drop_place = trans_place(fx, location);
 320                     let drop_fn_ty = drop_fn.ty(fx.tcx);
 321                     match ty.sty {
 322                         ty::Dynamic(..) => {
 323                             crate::abi::codegen_drop(fx, drop_place, drop_fn_ty);
 324                         }
 325                         _ => {
 326                             let arg_place = CPlace::new_stack_slot(
 327                                 fx,
 328                                 fx.tcx.mk_ref(
 329                                     &ty::RegionKind::ReErased,
 330                                     TypeAndMut {
 331                                         ty,
 332                                         mutbl: crate::rustc::hir::Mutability::MutMutable,
 333                                     },
 334                                 ),
 335                             );
 336                             drop_place.write_place_ref(fx, arg_place);
 337                             let arg_value = arg_place.to_cvalue(fx);
 338                             crate::abi::codegen_call_inner(
 339                                 fx,
 340                                 None,
 341                                 drop_fn_ty,
 342                                 vec![arg_value],
 343                                 None,
 344                             );
 345                         }
 346                     }
 347                 }
 348
 349                 let target_ebb = fx.get_ebb(*target);
 350                 fx.bcx.ins().jump(target_ebb, &[]);
 351             }
 352         };
 353     }
 354
 355     fx.bcx.seal_all_blocks();
 356     fx.bcx.finalize();
 357 }
 358
 359 fn trans_stmt<'a, 'tcx: 'a>(
 360     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 361     cur_ebb: Ebb,
 362     stmt: &Statement<'tcx>,
 363 ) {
 364     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 365
 366     fx.set_debug_loc(stmt.source_info);
 367
 368     #[cfg(debug_assertions)]
 369     match &stmt.kind {
 370         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 371         _ => {
 372             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 373             fx.add_comment(inst, format!("{:?}", stmt));
 374         }
 375     }
 376
 377     match &stmt.kind {
 378         StatementKind::SetDiscriminant {
 379             place,
 380             variant_index,
 381         } => {
 382             let place = trans_place(fx, place);
 383             let layout = place.layout();
 384             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 385                 return;
 386             }
 387             match layout.variants {
 388                 layout::Variants::Single { index } => {
 389                     assert_eq!(index, *variant_index);
 390                 }
 391                 layout::Variants::Multiple { discr_kind: layout::DiscriminantKind::Tag, .. } => {
 392                     let ptr = place.place_field(fx, mir::Field::new(0));
 393                     let to = layout
 394                         .ty
 395                         .ty_adt_def()
 396                         .unwrap()
 397                         .discriminant_for_variant(fx.tcx, *variant_index)
 398                         .val;
 399                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 400                     ptr.write_cvalue(fx, discr);
 401                 }
 402                 layout::Variants::Multiple {
 403                     discr_kind: layout::DiscriminantKind::Niche {
 404                         dataful_variant,
 405                         ref niche_variants,
 406                         niche_start,
 407                     },
 408                     ..
 409                 } => {
 410                     if *variant_index != dataful_variant {
 411                         let niche = place.place_field(fx, mir::Field::new(0));
 412                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 413                         let niche_value =
 414                             ((variant_index.as_u32() - niche_variants.start().as_u32()) as u128)
 415                                 .wrapping_add(niche_start);
 416                         // FIXME(eddyb) Check the actual primitive type here.
 417                         let niche_llval = if niche_value == 0 {
 418                             CValue::const_val(fx, niche.layout().ty, 0)
 419                         } else {
 420                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 421                         };
 422                         niche.write_cvalue(fx, niche_llval);
 423                     }
 424                 }
 425             }
 426         }
 427         StatementKind::Assign(to_place, rval) => {
 428             let lval = trans_place(fx, to_place);
 429             let dest_layout = lval.layout();
 430             match &**rval {
 431                 Rvalue::Use(operand) => {
 432                     let val = trans_operand(fx, operand);
 433                     lval.write_cvalue(fx, val);
 434                 }
 435                 Rvalue::Ref(_, _, place) => {
 436                     let place = trans_place(fx, place);
 437                     place.write_place_ref(fx, lval);
 438                 }
 439                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 440                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 441                     let lhs = trans_operand(fx, lhs);
 442                     let rhs = trans_operand(fx, rhs);
 443
 444                     let res = match ty.sty {
 445                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 446                         ty::Uint(_) => {
 447                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 448                         }
 449                         ty::Int(_) => {
 450                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 451                         }
 452                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 453                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 454                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 455                         ty::FnPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 456                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 457                     };
 458                     lval.write_cvalue(fx, res);
 459                 }
 460                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 461                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 462                     let lhs = trans_operand(fx, lhs);
 463                     let rhs = trans_operand(fx, rhs);
 464
 465                     let res = match ty.sty {
 466                         ty::Uint(_) => {
 467                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 468                         }
 469                         ty::Int(_) => {
 470                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 471                         }
 472                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 473                     };
 474                     lval.write_cvalue(fx, res);
 475                 }
 476                 Rvalue::UnaryOp(un_op, operand) => {
 477                     let operand = trans_operand(fx, operand);
 478                     let layout = operand.layout();
 479                     let val = operand.load_scalar(fx);
 480                     let res = match un_op {
 481                         UnOp::Not => {
 482                             match layout.ty.sty {
 483                                 ty::Bool => {
 484                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 485                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 486                                     fx.bcx.ins().bint(types::I8, res)
 487                                 }
 488                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 489                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 490                             }
 491                         }
 492                         UnOp::Neg => match layout.ty.sty {
 493                             ty::Int(_) => {
 494                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 495                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 496                                 fx.bcx.ins().isub(zero, val)
 497                             }
 498                             ty::Float(_) => fx.bcx.ins().fneg(val),
 499                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 500                         },
 501                     };
 502                     lval.write_cvalue(fx, CValue::ByVal(res, layout));
 503                 }
 504                 Rvalue::Cast(CastKind::ReifyFnPointer, operand, ty) => {
 505                     let layout = fx.layout_of(ty);
 506                     match fx
 507                         .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
 508                         .sty
 509                     {
 510                         ty::FnDef(def_id, substs) => {
 511                             let func_ref = fx.get_function_ref(
 512                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
 513                                     .unwrap(),
 514                             );
 515                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 516                             lval.write_cvalue(fx, CValue::ByVal(func_addr, layout));
 517                         }
 518                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 519                     }
 520                 }
 521                 Rvalue::Cast(CastKind::UnsafeFnPointer, operand, ty)
 522                 | Rvalue::Cast(CastKind::MutToConstPointer, operand, ty) => {
 523                     let operand = trans_operand(fx, operand);
 524                     let layout = fx.layout_of(ty);
 525                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 526                 }
 527                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 528                     let operand = trans_operand(fx, operand);
 529                     let from_ty = operand.layout().ty;
 530
 531                     fn is_fat_ptr<'a, 'tcx: 'a>(fx: &FunctionCx<'a, 'tcx, impl Backend>, ty: Ty<'tcx>) -> bool {
 532                         ty
 533                             .builtin_deref(true)
 534                             .map(|ty::TypeAndMut {ty: pointee_ty, mutbl: _ }| fx.layout_of(pointee_ty).is_unsized())
 535                             .unwrap_or(false)
 536                     }
 537
 538                     if is_fat_ptr(fx, from_ty) {
 539                         if is_fat_ptr(fx, to_ty) {
 540                             // fat-ptr -> fat-ptr
 541                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 542                         } else {
 543                             // fat-ptr -> thin-ptr
 544                             let (ptr, _extra) = operand.load_scalar_pair(fx);
 545                             lval.write_cvalue(fx, CValue::ByVal(ptr, dest_layout))
 546                         }
 547                     } else if let ty::Adt(adt_def, _substs) = from_ty.sty {
 548                         // enum -> discriminant value
 549                         assert!(adt_def.is_enum());
 550                         match to_ty.sty {
 551                             ty::Uint(_) | ty::Int(_) => {},
 552                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
 553                         }
 554
 555                         // FIXME avoid forcing to stack
 556                         let place =
 557                             CPlace::Addr(operand.force_stack(fx), None, operand.layout());
 558                         let discr = trans_get_discriminant(fx, place, fx.layout_of(to_ty));
 559                         lval.write_cvalue(fx, discr);
 560                     } else {
 561                         let from_clif_ty = fx.clif_type(from_ty).unwrap();
 562                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
 563                         let from = operand.load_scalar(fx);
 564
 565                         let signed = match from_ty.sty {
 566                             ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 567                             ty::Int(..) => true,
 568                             ty::Float(..) => false, // `signed` is unused for floats
 569                             _ => panic!("{}", from_ty),
 570                         };
 571
 572                         let res = if from_clif_ty.is_int() && to_clif_ty.is_int() {
 573                             // int-like -> int-like
 574                             crate::common::clif_intcast(
 575                                 fx,
 576                                 from,
 577                                 to_clif_ty,
 578                                 signed,
 579                             )
 580                         } else if from_clif_ty.is_int() && to_clif_ty.is_float() {
 581                             // int-like -> float
 582                             // FIXME missing encoding for fcvt_from_sint.f32.i8
 583                             let from = if from_clif_ty == types::I8 || from_clif_ty == types::I16 {
 584                                 fx.bcx.ins().uextend(types::I32, from)
 585                             } else {
 586                                 from
 587                             };
 588                             if signed {
 589                                 fx.bcx.ins().fcvt_from_sint(to_clif_ty, from)
 590                             } else {
 591                                 fx.bcx.ins().fcvt_from_uint(to_clif_ty, from)
 592                             }
 593                         } else if from_clif_ty.is_float() && to_clif_ty.is_int() {
 594                             // float -> int-like
 595                             let from = operand.load_scalar(fx);
 596                             if signed {
 597                                 fx.bcx.ins().fcvt_to_sint_sat(to_clif_ty, from)
 598                             } else {
 599                                 fx.bcx.ins().fcvt_to_uint_sat(to_clif_ty, from)
 600                             }
 601                         } else if from_clif_ty.is_float() && to_clif_ty.is_float() {
 602                             // float -> float
 603                             match (from_clif_ty, to_clif_ty) {
 604                                 (types::F32, types::F64) => {
 605                                     fx.bcx.ins().fpromote(types::F64, from)
 606                                 }
 607                                 (types::F64, types::F32) => {
 608                                     fx.bcx.ins().fdemote(types::F32, from)
 609                                 }
 610                                 _ => from,
 611                             }
 612                         } else {
 613                             unimpl!("rval misc {:?} {:?}", from_ty, to_ty)
 614                         };
 615                         lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 616                     }
 617                 }
 618                 Rvalue::Cast(CastKind::ClosureFnPointer(_), operand, _ty) => {
 619                     let operand = trans_operand(fx, operand);
 620                     match operand.layout().ty.sty {
 621                         ty::Closure(def_id, substs) => {
 622                             let instance = rustc_mir::monomorphize::resolve_closure(
 623                                 fx.tcx,
 624                                 def_id,
 625                                 substs,
 626                                 ty::ClosureKind::FnOnce,
 627                             );
 628                             let func_ref = fx.get_function_ref(instance);
 629                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 630                             lval.write_cvalue(fx, CValue::ByVal(func_addr, lval.layout()));
 631                         }
 632                         _ => {
 633                             bug!("{} cannot be cast to a fn ptr", operand.layout().ty)
 634                         }
 635                     }
 636                 }
 637                 Rvalue::Cast(CastKind::Unsize, operand, _ty) => {
 638                     let operand = trans_operand(fx, operand);
 639                     operand.unsize_value(fx, lval);
 640                 }
 641                 Rvalue::Discriminant(place) => {
 642                     let place = trans_place(fx, place);
 643                     let discr = trans_get_discriminant(fx, place, dest_layout);
 644                     lval.write_cvalue(fx, discr);
 645                 }
 646                 Rvalue::Repeat(operand, times) => {
 647                     let operand = trans_operand(fx, operand);
 648                     for i in 0..*times {
 649                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 650                         let to = lval.place_index(fx, index);
 651                         to.write_cvalue(fx, operand);
 652                     }
 653                 }
 654                 Rvalue::Len(place) => {
 655                     let place = trans_place(fx, place);
 656                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 657                     let len = codegen_array_len(fx, place);
 658                     lval.write_cvalue(fx, CValue::ByVal(len, usize_layout));
 659                 }
 660                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 661                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 662
 663                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 664                     let layout = fx.layout_of(content_ty);
 665                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 666                     let llalign = fx
 667                         .bcx
 668                         .ins()
 669                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 670                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 671
 672                     // Allocate space:
 673                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 674                         Ok(id) => id,
 675                         Err(s) => {
 676                             fx.tcx
 677                                 .sess
 678                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 679                         }
 680                     };
 681                     let instance = ty::Instance::mono(fx.tcx, def_id);
 682                     let func_ref = fx.get_function_ref(instance);
 683                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 684                     let ptr = fx.bcx.inst_results(call)[0];
 685                     lval.write_cvalue(fx, CValue::ByVal(ptr, box_layout));
 686                 }
 687                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 688                     assert!(lval
 689                         .layout()
 690                         .ty
 691                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 692                     let ty_size = fx.layout_of(ty).size.bytes();
 693                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 694                     lval.write_cvalue(fx, val);
 695                 }
 696                 Rvalue::Aggregate(kind, operands) => match **kind {
 697                     AggregateKind::Array(_ty) => {
 698                         for (i, operand) in operands.into_iter().enumerate() {
 699                             let operand = trans_operand(fx, operand);
 700                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 701                             let to = lval.place_index(fx, index);
 702                             to.write_cvalue(fx, operand);
 703                         }
 704                     }
 705                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 706                 },
 707             }
 708         }
 709         StatementKind::StorageLive(_)
 710         | StatementKind::StorageDead(_)
 711         | StatementKind::Nop
 712         | StatementKind::FakeRead(..)
 713         | StatementKind::Retag { .. }
 714         | StatementKind::AscribeUserType(..) => {}
 715
 716         StatementKind::InlineAsm { .. } => unimpl!("Inline assembly is not supported"),
 717     }
 718 }
 719
 720 fn codegen_array_len<'a, 'tcx: 'a>(
 721     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 722     place: CPlace<'tcx>,
 723 ) -> Value {
 724     match place.layout().ty.sty {
 725         ty::Array(_elem_ty, len) => {
 726             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx) as i64;
 727             fx.bcx.ins().iconst(fx.pointer_type, len)
 728         }
 729         ty::Slice(_elem_ty) => place
 730             .to_addr_maybe_unsized(fx)
 731             .1
 732             .expect("Length metadata for slice place"),
 733         _ => bug!("Rvalue::Len({:?})", place),
 734     }
 735 }
 736
 737 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 738     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 739     place: CPlace<'tcx>,
 740     dest_layout: TyLayout<'tcx>,
 741 ) -> CValue<'tcx> {
 742     let layout = place.layout();
 743
 744     if layout.abi == layout::Abi::Uninhabited {
 745         return trap_unreachable_ret_value(fx, dest_layout);
 746     }
 747
 748     let (discr_scalar, discr_kind) = match &layout.variants {
 749         layout::Variants::Single { index } => {
 750             let discr_val = layout
 751                 .ty
 752                 .ty_adt_def()
 753                 .map_or(index.as_u32() as u128, |def| {
 754                     def.discriminant_for_variant(fx.tcx, *index).val
 755                 });
 756             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 757         }
 758         layout::Variants::Multiple { discr, discr_kind, variants: _ } => (discr, discr_kind),
 759     };
 760
 761     let discr = place.place_field(fx, mir::Field::new(0)).to_cvalue(fx);
 762     let discr_ty = discr.layout().ty;
 763     let lldiscr = discr.load_scalar(fx);
 764     match discr_kind {
 765         layout::DiscriminantKind::Tag => {
 766             let signed = match discr_scalar.value {
 767                 layout::Int(_, signed) => signed,
 768                 _ => false,
 769             };
 770             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 771             return CValue::ByVal(val, dest_layout);
 772         }
 773         layout::DiscriminantKind::Niche {
 774             dataful_variant,
 775             ref niche_variants,
 776             niche_start,
 777         } => {
 778             let niche_llty = fx.clif_type(discr_ty).unwrap();
 779             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 780             if niche_variants.start() == niche_variants.end() {
 781                 let b = fx
 782                     .bcx
 783                     .ins()
 784                     .icmp_imm(IntCC::Equal, lldiscr, *niche_start as u64 as i64);
 785                 let if_true = fx
 786                     .bcx
 787                     .ins()
 788                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 789                 let if_false = fx
 790                     .bcx
 791                     .ins()
 792                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 793                 let val = fx.bcx.ins().select(b, if_true, if_false);
 794                 return CValue::ByVal(val, dest_layout);
 795             } else {
 796                 // Rebase from niche values to discriminant values.
 797                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 798                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 799                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 800                 let b = fx.bcx.ins().icmp_imm(
 801                     IntCC::UnsignedLessThanOrEqual,
 802                     lldiscr,
 803                     niche_variants.end().as_u32() as i64,
 804                 );
 805                 let if_true =
 806                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 807                 let if_false = fx
 808                     .bcx
 809                     .ins()
 810                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 811                 let val = fx.bcx.ins().select(b, if_true, if_false);
 812                 return CValue::ByVal(val, dest_layout);
 813             }
 814         }
 815     }
 816 }
 817
 818 macro_rules! binop_match {
 819     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 820         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 821     };
 822     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 823         assert_eq!($fx.tcx.types.bool, $ret_ty);
 824         let ret_layout = $fx.layout_of($ret_ty);
 825
 826         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 827         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 828     }};
 829     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 830         assert_eq!($fx.tcx.types.bool, $ret_ty);
 831         let ret_layout = $fx.layout_of($ret_ty);
 832         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 833         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 834     }};
 835     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 836         $body
 837     }};
 838     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 839         let ret_layout = $fx.layout_of($ret_ty);
 840         CValue::ByVal($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 841     }};
 842     (
 843         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 844         $(
 845             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 846         )*
 847     ) => {{
 848         let lhs = $lhs.load_scalar($fx);
 849         let rhs = $rhs.load_scalar($fx);
 850         match ($bin_op, $signed) {
 851             $(
 852                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 853             )*
 854         }
 855     }}
 856 }
 857
 858 fn trans_bool_binop<'a, 'tcx: 'a>(
 859     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 860     bin_op: BinOp,
 861     lhs: CValue<'tcx>,
 862     rhs: CValue<'tcx>,
 863     ty: Ty<'tcx>,
 864 ) -> CValue<'tcx> {
 865     let res = binop_match! {
 866         fx, bin_op, false, lhs, rhs, ty, "bool";
 867         Add (_) bug;
 868         Sub (_) bug;
 869         Mul (_) bug;
 870         Div (_) bug;
 871         Rem (_) bug;
 872         BitXor (_) bxor;
 873         BitAnd (_) band;
 874         BitOr (_) bor;
 875         Shl (_) bug;
 876         Shr (_) bug;
 877
 878         Eq (_) icmp(Equal);
 879         Lt (_) icmp(UnsignedLessThan);
 880         Le (_) icmp(UnsignedLessThanOrEqual);
 881         Ne (_) icmp(NotEqual);
 882         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 883         Gt (_) icmp(UnsignedGreaterThan);
 884
 885         Offset (_) bug;
 886     };
 887
 888     res
 889 }
 890
 891 pub fn trans_int_binop<'a, 'tcx: 'a>(
 892     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 893     bin_op: BinOp,
 894     lhs: CValue<'tcx>,
 895     rhs: CValue<'tcx>,
 896     out_ty: Ty<'tcx>,
 897     signed: bool,
 898 ) -> CValue<'tcx> {
 899     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 900         assert_eq!(
 901             lhs.layout().ty,
 902             rhs.layout().ty,
 903             "int binop requires lhs and rhs of same type"
 904         );
 905     }
 906     binop_match! {
 907         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 908         Add (_) iadd;
 909         Sub (_) isub;
 910         Mul (_) imul;
 911         Div (false) udiv;
 912         Div (true) sdiv;
 913         Rem (false) urem;
 914         Rem (true) srem;
 915         BitXor (_) bxor;
 916         BitAnd (_) band;
 917         BitOr (_) bor;
 918         Shl (_) ishl;
 919         Shr (false) ushr;
 920         Shr (true) sshr;
 921
 922         Eq (_) icmp(Equal);
 923         Lt (false) icmp(UnsignedLessThan);
 924         Lt (true) icmp(SignedLessThan);
 925         Le (false) icmp(UnsignedLessThanOrEqual);
 926         Le (true) icmp(SignedLessThanOrEqual);
 927         Ne (_) icmp(NotEqual);
 928         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 929         Ge (true) icmp(SignedGreaterThanOrEqual);
 930         Gt (false) icmp(UnsignedGreaterThan);
 931         Gt (true) icmp(SignedGreaterThan);
 932
 933         Offset (_) bug;
 934     }
 935 }
 936
 937 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 938     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 939     bin_op: BinOp,
 940     in_lhs: CValue<'tcx>,
 941     in_rhs: CValue<'tcx>,
 942     out_ty: Ty<'tcx>,
 943     signed: bool,
 944 ) -> CValue<'tcx> {
 945     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 946         assert_eq!(
 947             in_lhs.layout().ty,
 948             in_rhs.layout().ty,
 949             "checked int binop requires lhs and rhs of same type"
 950         );
 951     }
 952
 953     let lhs = in_lhs.load_scalar(fx);
 954     let rhs = in_rhs.load_scalar(fx);
 955     let res = match bin_op {
 956         BinOp::Add => fx.bcx.ins().iadd(lhs, rhs),
 957         BinOp::Sub => fx.bcx.ins().isub(lhs, rhs),
 958         BinOp::Mul => fx.bcx.ins().imul(lhs, rhs),
 959         BinOp::Shl => fx.bcx.ins().ishl(lhs, rhs),
 960         BinOp::Shr => {
 961             if !signed {
 962                 fx.bcx.ins().ushr(lhs, rhs)
 963             } else {
 964                 fx.bcx.ins().sshr(lhs, rhs)
 965             }
 966         }
 967         _ => bug!(
 968             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 969             bin_op,
 970             in_lhs,
 971             in_rhs
 972         ),
 973     };
 974
 975     // TODO: check for overflow
 976     let has_overflow = fx.bcx.ins().iconst(types::I8, 0);
 977
 978     let out_place = CPlace::new_stack_slot(fx, out_ty);
 979     let out_layout = out_place.layout();
 980     out_place.write_cvalue(fx, CValue::ByValPair(res, has_overflow, out_layout));
 981
 982     out_place.to_cvalue(fx)
 983 }
 984
 985 fn trans_float_binop<'a, 'tcx: 'a>(
 986     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 987     bin_op: BinOp,
 988     lhs: CValue<'tcx>,
 989     rhs: CValue<'tcx>,
 990     ty: Ty<'tcx>,
 991 ) -> CValue<'tcx> {
 992     let res = binop_match! {
 993         fx, bin_op, false, lhs, rhs, ty, "float";
 994         Add (_) fadd;
 995         Sub (_) fsub;
 996         Mul (_) fmul;
 997         Div (_) fdiv;
 998         Rem (_) custom(|| {
 999             assert_eq!(lhs.layout().ty, ty);
1000             assert_eq!(rhs.layout().ty, ty);
1001             match ty.sty {
1002                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
1003                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
1004                 _ => bug!(),
1005             }
1006         });
1007         BitXor (_) bxor;
1008         BitAnd (_) band;
1009         BitOr (_) bor;
1010         Shl (_) bug;
1011         Shr (_) bug;
1012
1013         Eq (_) fcmp(Equal);
1014         Lt (_) fcmp(LessThan);
1015         Le (_) fcmp(LessThanOrEqual);
1016         Ne (_) fcmp(NotEqual);
1017         Ge (_) fcmp(GreaterThanOrEqual);
1018         Gt (_) fcmp(GreaterThan);
1019
1020         Offset (_) bug;
1021     };
1022
1023     res
1024 }
1025
1026 fn trans_char_binop<'a, 'tcx: 'a>(
1027     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1028     bin_op: BinOp,
1029     lhs: CValue<'tcx>,
1030     rhs: CValue<'tcx>,
1031     ty: Ty<'tcx>,
1032 ) -> CValue<'tcx> {
1033     let res = binop_match! {
1034         fx, bin_op, false, lhs, rhs, ty, "char";
1035         Add (_) bug;
1036         Sub (_) bug;
1037         Mul (_) bug;
1038         Div (_) bug;
1039         Rem (_) bug;
1040         BitXor (_) bug;
1041         BitAnd (_) bug;
1042         BitOr (_) bug;
1043         Shl (_) bug;
1044         Shr (_) bug;
1045
1046         Eq (_) icmp(Equal);
1047         Lt (_) icmp(UnsignedLessThan);
1048         Le (_) icmp(UnsignedLessThanOrEqual);
1049         Ne (_) icmp(NotEqual);
1050         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1051         Gt (_) icmp(UnsignedGreaterThan);
1052
1053         Offset (_) bug;
1054     };
1055
1056     res
1057 }
1058
1059 fn trans_ptr_binop<'a, 'tcx: 'a>(
1060     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1061     bin_op: BinOp,
1062     lhs: CValue<'tcx>,
1063     rhs: CValue<'tcx>,
1064     ret_ty: Ty<'tcx>,
1065 ) -> CValue<'tcx> {
1066     let not_fat = match lhs.layout().ty.sty {
1067         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1068             ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
1069         }
1070         ty::FnPtr(..) => true,
1071         _ => bug!("trans_ptr_binop on non ptr"),
1072     };
1073     if not_fat {
1074         if let BinOp::Offset = bin_op {
1075             let (base, offset) = (lhs, rhs.load_scalar(fx));
1076             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
1077             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
1078             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
1079             let base_val = base.load_scalar(fx);
1080             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
1081             return CValue::ByVal(res, base.layout());
1082         }
1083
1084         binop_match! {
1085             fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1086             Add (_) bug;
1087             Sub (_) bug;
1088             Mul (_) bug;
1089             Div (_) bug;
1090             Rem (_) bug;
1091             BitXor (_) bug;
1092             BitAnd (_) bug;
1093             BitOr (_) bug;
1094             Shl (_) bug;
1095             Shr (_) bug;
1096
1097             Eq (_) icmp(Equal);
1098             Lt (_) icmp(UnsignedLessThan);
1099             Le (_) icmp(UnsignedLessThanOrEqual);
1100             Ne (_) icmp(NotEqual);
1101             Ge (_) icmp(UnsignedGreaterThanOrEqual);
1102             Gt (_) icmp(UnsignedGreaterThan);
1103
1104             Offset (_) bug; // Handled above
1105         }
1106     } else {
1107         let (lhs_ptr, lhs_extra) = lhs.load_scalar_pair(fx);
1108         let (rhs_ptr, rhs_extra) = rhs.load_scalar_pair(fx);
1109         let res = match bin_op {
1110             BinOp::Eq => {
1111                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1112                 let extra_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_extra, rhs_extra);
1113                 fx.bcx.ins().band(ptr_eq, extra_eq)
1114             }
1115             BinOp::Ne => {
1116                 let ptr_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_ptr, rhs_ptr);
1117                 let extra_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_extra, rhs_extra);
1118                 fx.bcx.ins().bor(ptr_ne, extra_ne)
1119             }
1120             _ => unimplemented!(
1121                 "trans_ptr_binop({:?}, <fat ptr>, <fat ptr>) not implemented",
1122                 bin_op
1123             ),
1124         };
1125
1126         assert_eq!(fx.tcx.types.bool, ret_ty);
1127         let ret_layout = fx.layout_of(ret_ty);
1128         CValue::ByVal(fx.bcx.ins().bint(types::I8, res), ret_layout)
1129     }
1130 }
1131
1132 pub fn trans_place<'a, 'tcx: 'a>(
1133     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1134     place: &Place<'tcx>,
1135 ) -> CPlace<'tcx> {
1136     match place {
1137         Place::Base(base) => match base {
1138             PlaceBase::Local(local) => fx.get_local_place(*local),
1139             PlaceBase::Static(static_) => match static_.kind {
1140                 StaticKind::Static(def_id) => {
1141                     crate::constant::codegen_static_ref(fx, def_id, static_.ty)
1142                 }
1143                 StaticKind::Promoted(promoted) => {
1144                     crate::constant::trans_promoted(fx, promoted, static_.ty)
1145                 }
1146             }
1147         }
1148         Place::Projection(projection) => {
1149             let base = trans_place(fx, &projection.base);
1150             match projection.elem {
1151                 ProjectionElem::Deref => base.place_deref(fx),
1152                 ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1153                 ProjectionElem::Index(local) => {
1154                     let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1155                     base.place_index(fx, index)
1156                 }
1157                 ProjectionElem::ConstantIndex {
1158                     offset,
1159                     min_length: _,
1160                     from_end,
1161                 } => {
1162                     let index = if !from_end {
1163                         fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1164                     } else {
1165                         let len = codegen_array_len(fx, base);
1166                         fx.bcx.ins().iadd_imm(len, -(offset as i64))
1167                     };
1168                     base.place_index(fx, index)
1169                 }
1170                 ProjectionElem::Subslice { from, to } => {
1171                     // These indices are generated by slice patterns.
1172                     // slice[from:-to] in Python terms.
1173
1174                     match base.layout().ty.sty {
1175                         ty::Array(elem_ty, len) => {
1176                             let elem_layout = fx.layout_of(elem_ty);
1177                             let ptr = base.to_addr(fx);
1178                             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx);
1179                             CPlace::Addr(
1180                                 fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1181                                 None,
1182                                 fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
1183                             )
1184                         }
1185                         ty::Slice(elem_ty) => {
1186                             let elem_layout = fx.layout_of(elem_ty);
1187                             let (ptr, len) = base.to_addr_maybe_unsized(fx);
1188                             let len = len.unwrap();
1189                             CPlace::Addr(
1190                                 fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1191                                 Some(fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64))),
1192                                 base.layout(),
1193                             )
1194                         }
1195                         _ => unreachable!(),
1196                     }
1197                 }
1198                 ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1199             }
1200         }
1201     }
1202 }
1203
1204 pub fn trans_operand<'a, 'tcx>(
1205     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1206     operand: &Operand<'tcx>,
1207 ) -> CValue<'tcx> {
1208     match operand {
1209         Operand::Move(place) | Operand::Copy(place) => {
1210             let cplace = trans_place(fx, place);
1211             cplace.to_cvalue(fx)
1212         }
1213         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1214     }
1215 }