src/base.rs

   1 use rustc::ty::adjustment::PointerCast;
   2
   3 use crate::prelude::*;
   4
   5 pub fn trans_fn<'a, 'clif, 'tcx: 'a, B: Backend + 'static>(
   6     cx: &mut crate::CodegenCx<'clif, 'tcx, B>,
   7     instance: Instance<'tcx>,
   8     linkage: Linkage,
   9 ) {
  10     let tcx = cx.tcx;
  11
  12     let mir = tcx.instance_mir(instance.def);
  13
  14     // Declare function
  15     let (name, sig) = get_function_name_and_sig(tcx, instance, false);
  16     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
  17     let mut debug_context = cx
  18         .debug_context
  19         .as_mut()
  20         .map(|debug_context| FunctionDebugContext::new(tcx, debug_context, mir, &name, &sig));
  21
  22     // Make FunctionBuilder
  23     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
  24     let mut func_ctx = FunctionBuilderContext::new();
  25     let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
  26
  27     // Predefine ebb's
  28     let start_ebb = bcx.create_ebb();
  29     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
  30     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
  31         ebb_map.insert(bb, bcx.create_ebb());
  32     }
  33
  34     // Make FunctionCx
  35     let pointer_type = cx.module.target_config().pointer_type();
  36     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
  37
  38     let mut fx = FunctionCx {
  39         tcx,
  40         module: cx.module,
  41         pointer_type,
  42
  43         instance,
  44         mir,
  45
  46         bcx,
  47         ebb_map,
  48         local_map: HashMap::new(),
  49
  50         clif_comments,
  51         constants: &mut cx.ccx,
  52         caches: &mut cx.caches,
  53         source_info_set: indexmap::IndexSet::new(),
  54     };
  55
  56     with_unimpl_span(fx.mir.span, || {
  57         crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
  58         codegen_fn_content(&mut fx);
  59     });
  60
  61     // Recover all necessary data from fx, before accessing func will prevent future access to it.
  62     let instance = fx.instance;
  63     let clif_comments = fx.clif_comments;
  64     let source_info_set = fx.source_info_set;
  65
  66     #[cfg(debug_assertions)]
  67     crate::pretty_clif::write_clif_file(cx.tcx, "unopt", instance, &func, &clif_comments, None);
  68
  69     // Verify function
  70     verify_func(tcx, &clif_comments, &func);
  71
  72     // Define function
  73     let context = &mut cx.caches.context;
  74     context.func = func;
  75     cx.module
  76         .define_function(func_id, context)
  77         .unwrap();
  78
  79     let value_ranges = context.build_value_labels_ranges(cx.module.isa()).expect("value location ranges");
  80
  81     // Write optimized function to file for debugging
  82     #[cfg(debug_assertions)]
  83     crate::pretty_clif::write_clif_file(cx.tcx, "opt", instance, &context.func, &clif_comments, Some(&value_ranges));
  84
  85     // Define debuginfo for function
  86     let isa = cx.module.isa();
  87     debug_context
  88         .as_mut()
  89         .map(|x| x.define(tcx, context, isa, &source_info_set));
  90
  91     // Clear context to make it usable for the next function
  92     context.clear();
  93 }
  94
  95 fn verify_func(tcx: TyCtxt, writer: &crate::pretty_clif::CommentWriter, func: &Function) {
  96     let flags = settings::Flags::new(settings::builder());
  97     match ::cranelift::codegen::verify_function(&func, &flags) {
  98         Ok(_) => {}
  99         Err(err) => {
 100             tcx.sess.err(&format!("{:?}", err));
 101             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 102                 &func,
 103                 None,
 104                 Some(Box::new(writer)),
 105                 err,
 106             );
 107             tcx.sess
 108                 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
 109         }
 110     }
 111 }
 112
 113 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 114     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 115         if bb_data.is_cleanup {
 116             // Unwinding after panicking is not supported
 117             continue;
 118         }
 119
 120         let ebb = fx.get_ebb(bb);
 121         fx.bcx.switch_to_block(ebb);
 122
 123         fx.bcx.ins().nop();
 124         for stmt in &bb_data.statements {
 125             fx.set_debug_loc(stmt.source_info);
 126             trans_stmt(fx, ebb, stmt);
 127         }
 128
 129         #[cfg(debug_assertions)]
 130         {
 131             let mut terminator_head = "\n".to_string();
 132             bb_data
 133                 .terminator()
 134                 .kind
 135                 .fmt_head(&mut terminator_head)
 136                 .unwrap();
 137             let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 138             fx.add_comment(inst, terminator_head);
 139         }
 140
 141         fx.set_debug_loc(bb_data.terminator().source_info);
 142
 143         match &bb_data.terminator().kind {
 144             TerminatorKind::Goto { target } => {
 145                 let ebb = fx.get_ebb(*target);
 146                 fx.bcx.ins().jump(ebb, &[]);
 147             }
 148             TerminatorKind::Return => {
 149                 crate::abi::codegen_return(fx);
 150             }
 151             TerminatorKind::Assert {
 152                 cond,
 153                 expected,
 154                 msg,
 155                 target,
 156                 cleanup: _,
 157             } => {
 158                 let cond = trans_operand(fx, cond).load_scalar(fx);
 159                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 160                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 161                 let target = fx.get_ebb(*target);
 162                 if *expected {
 163                     fx.bcx.ins().brnz(cond, target, &[]);
 164                 } else {
 165                     fx.bcx.ins().brz(cond, target, &[]);
 166                 };
 167                 trap_panic(fx, format!("[panic] Assert {:?} at {:?} failed.", msg, bb_data.terminator().source_info.span));
 168             }
 169
 170             TerminatorKind::SwitchInt {
 171                 discr,
 172                 switch_ty: _,
 173                 values,
 174                 targets,
 175             } => {
 176                 let discr = trans_operand(fx, discr).load_scalar(fx);
 177                 let mut switch = ::cranelift::frontend::Switch::new();
 178                 for (i, value) in values.iter().enumerate() {
 179                     let ebb = fx.get_ebb(targets[i]);
 180                     switch.set_entry(*value as u64, ebb);
 181                 }
 182                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 183                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 184             }
 185             TerminatorKind::Call {
 186                 func,
 187                 args,
 188                 destination,
 189                 cleanup: _,
 190                 from_hir_call: _,
 191             } => {
 192                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 193             }
 194             TerminatorKind::Resume | TerminatorKind::Abort => {
 195                 trap_unreachable(fx, "[corruption] Unwinding bb reached.");
 196             }
 197             TerminatorKind::Unreachable => {
 198                 trap_unreachable(fx, "[corruption] Hit unreachable code.");
 199             }
 200             TerminatorKind::Yield { .. }
 201             | TerminatorKind::FalseEdges { .. }
 202             | TerminatorKind::FalseUnwind { .. }
 203             | TerminatorKind::DropAndReplace { .. }
 204             | TerminatorKind::GeneratorDrop => {
 205                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 206             }
 207             TerminatorKind::Drop {
 208                 location,
 209                 target,
 210                 unwind: _,
 211             } => {
 212                 let drop_place = trans_place(fx, location);
 213                 crate::abi::codegen_drop(fx, drop_place);
 214
 215                 let target_ebb = fx.get_ebb(*target);
 216                 fx.bcx.ins().jump(target_ebb, &[]);
 217             }
 218         };
 219     }
 220
 221     fx.bcx.seal_all_blocks();
 222     fx.bcx.finalize();
 223 }
 224
 225 fn trans_stmt<'a, 'tcx: 'a>(
 226     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 227     cur_ebb: Ebb,
 228     stmt: &Statement<'tcx>,
 229 ) {
 230     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 231
 232     fx.set_debug_loc(stmt.source_info);
 233
 234     #[cfg(debug_assertions)]
 235     match &stmt.kind {
 236         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 237         _ => {
 238             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 239             fx.add_comment(inst, format!("{:?}", stmt));
 240         }
 241     }
 242
 243     match &stmt.kind {
 244         StatementKind::SetDiscriminant {
 245             place,
 246             variant_index,
 247         } => {
 248             let place = trans_place(fx, place);
 249             let layout = place.layout();
 250             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 251                 return;
 252             }
 253             match layout.variants {
 254                 layout::Variants::Single { index } => {
 255                     assert_eq!(index, *variant_index);
 256                 }
 257                 layout::Variants::Multiple {
 258                     discr: _,
 259                     discr_index,
 260                     discr_kind: layout::DiscriminantKind::Tag,
 261                     variants: _,
 262                 } => {
 263                     let ptr = place.place_field(fx, mir::Field::new(discr_index));
 264                     let to = layout
 265                         .ty
 266                         .discriminant_for_variant(fx.tcx, *variant_index)
 267                         .unwrap()
 268                         .val;
 269                     let discr = CValue::const_val(fx, ptr.layout().ty, to);
 270                     ptr.write_cvalue(fx, discr);
 271                 }
 272                 layout::Variants::Multiple {
 273                     discr: _,
 274                     discr_index,
 275                     discr_kind: layout::DiscriminantKind::Niche {
 276                         dataful_variant,
 277                         ref niche_variants,
 278                         niche_start,
 279                     },
 280                     variants: _,
 281                 } => {
 282                     if *variant_index != dataful_variant {
 283                         let niche = place.place_field(fx, mir::Field::new(discr_index));
 284                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 285                         let niche_value =
 286                             ((variant_index.as_u32() - niche_variants.start().as_u32()) as u128)
 287                                 .wrapping_add(niche_start);
 288                         // FIXME(eddyb) Check the actual primitive type here.
 289                         let niche_llval = if niche_value == 0 {
 290                             CValue::const_val(fx, niche.layout().ty, 0)
 291                         } else {
 292                             CValue::const_val(fx, niche.layout().ty, niche_value)
 293                         };
 294                         niche.write_cvalue(fx, niche_llval);
 295                     }
 296                 }
 297             }
 298         }
 299         StatementKind::Assign(to_place, rval) => {
 300             let lval = trans_place(fx, to_place);
 301             let dest_layout = lval.layout();
 302             match &**rval {
 303                 Rvalue::Use(operand) => {
 304                     let val = trans_operand(fx, operand);
 305                     lval.write_cvalue(fx, val);
 306                 }
 307                 Rvalue::Ref(_, _, place) => {
 308                     let place = trans_place(fx, place);
 309                     place.write_place_ref(fx, lval);
 310                 }
 311                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 312                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 313                     let lhs = trans_operand(fx, lhs);
 314                     let rhs = trans_operand(fx, rhs);
 315
 316                     let res = match ty.sty {
 317                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs),
 318                         ty::Uint(_) => {
 319                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 320                         }
 321                         ty::Int(_) => {
 322                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 323                         }
 324                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 325                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 326                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 327                         ty::FnPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 328                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 329                     };
 330                     lval.write_cvalue(fx, res);
 331                 }
 332                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 333                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 334                     let lhs = trans_operand(fx, lhs);
 335                     let rhs = trans_operand(fx, rhs);
 336
 337                     let signed = match ty.sty {
 338                         ty::Uint(_) => false,
 339                         ty::Int(_) => true,
 340                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 341                     };
 342
 343                     let res = if !fx.tcx.sess.overflow_checks() {
 344                         let val = trans_int_binop(fx, *bin_op, lhs, rhs, lhs.layout().ty, signed).load_scalar(fx);
 345                         let is_overflow = fx.bcx.ins().iconst(types::I8, 0);
 346                         CValue::by_val_pair(val, is_overflow, lval.layout())
 347                     } else {
 348                         trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, signed)
 349                     };
 350
 351                     lval.write_cvalue(fx, res);
 352                 }
 353                 Rvalue::UnaryOp(un_op, operand) => {
 354                     let operand = trans_operand(fx, operand);
 355                     let layout = operand.layout();
 356                     let val = operand.load_scalar(fx);
 357                     let res = match un_op {
 358                         UnOp::Not => {
 359                             match layout.ty.sty {
 360                                 ty::Bool => {
 361                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 362                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 363                                     fx.bcx.ins().bint(types::I8, res)
 364                                 }
 365                                 ty::Uint(_) | ty::Int(_) => {
 366                                     fx.bcx.ins().bnot(val)
 367                                 }
 368                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 369                             }
 370                         }
 371                         UnOp::Neg => match layout.ty.sty {
 372                             ty::Int(_) => {
 373                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 374                                 if clif_ty == types::I128 {
 375                                     crate::trap::trap_unreachable_ret_value(fx, layout, "i128 neg is not yet supported").load_scalar(fx)
 376                                 } else {
 377                                     let zero = fx.bcx.ins().iconst(clif_ty, 0);
 378                                     fx.bcx.ins().isub(zero, val)
 379                                 }
 380                             }
 381                             ty::Float(_) => fx.bcx.ins().fneg(val),
 382                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 383                         },
 384                     };
 385                     lval.write_cvalue(fx, CValue::by_val(res, layout));
 386                 }
 387                 Rvalue::Cast(CastKind::Pointer(PointerCast::ReifyFnPointer), operand, ty) => {
 388                     let layout = fx.layout_of(ty);
 389                     match fx
 390                         .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
 391                         .sty
 392                     {
 393                         ty::FnDef(def_id, substs) => {
 394                             let func_ref = fx.get_function_ref(
 395                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
 396                                     .unwrap(),
 397                             );
 398                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 399                             lval.write_cvalue(fx, CValue::by_val(func_addr, layout));
 400                         }
 401                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 402                     }
 403                 }
 404                 Rvalue::Cast(CastKind::Pointer(PointerCast::UnsafeFnPointer), operand, ty)
 405                 | Rvalue::Cast(CastKind::Pointer(PointerCast::MutToConstPointer), operand, ty) => {
 406                     let operand = trans_operand(fx, operand);
 407                     let layout = fx.layout_of(ty);
 408                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 409                 }
 410                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 411                     let operand = trans_operand(fx, operand);
 412                     let from_ty = operand.layout().ty;
 413
 414                     fn is_fat_ptr<'a, 'tcx: 'a>(fx: &FunctionCx<'a, 'tcx, impl Backend>, ty: Ty<'tcx>) -> bool {
 415                         ty
 416                             .builtin_deref(true)
 417                             .map(|ty::TypeAndMut {ty: pointee_ty, mutbl: _ }| fx.layout_of(pointee_ty).is_unsized())
 418                             .unwrap_or(false)
 419                     }
 420
 421                     if is_fat_ptr(fx, from_ty) {
 422                         if is_fat_ptr(fx, to_ty) {
 423                             // fat-ptr -> fat-ptr
 424                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 425                         } else {
 426                             // fat-ptr -> thin-ptr
 427                             let (ptr, _extra) = operand.load_scalar_pair(fx);
 428                             lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
 429                         }
 430                     } else if let ty::Adt(adt_def, _substs) = from_ty.sty {
 431                         // enum -> discriminant value
 432                         assert!(adt_def.is_enum());
 433                         match to_ty.sty {
 434                             ty::Uint(_) | ty::Int(_) => {},
 435                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
 436                         }
 437
 438                         // FIXME avoid forcing to stack
 439                         let place =
 440                             CPlace::for_addr(operand.force_stack(fx), operand.layout());
 441                         let discr = trans_get_discriminant(fx, place, fx.layout_of(to_ty));
 442                         lval.write_cvalue(fx, discr);
 443                     } else {
 444                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
 445                         let from = operand.load_scalar(fx);
 446
 447                         let signed = match from_ty.sty {
 448                             ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 449                             ty::Int(..) => true,
 450                             ty::Float(..) => false, // `signed` is unused for floats
 451                             _ => panic!("{}", from_ty),
 452                         };
 453
 454                         let res = clif_int_or_float_cast(fx, from, to_clif_ty, signed);
 455                         lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
 456                     }
 457                 }
 458                 Rvalue::Cast(CastKind::Pointer(PointerCast::ClosureFnPointer(_)), operand, _ty) => {
 459                     let operand = trans_operand(fx, operand);
 460                     match operand.layout().ty.sty {
 461                         ty::Closure(def_id, substs) => {
 462                             let instance = Instance::resolve_closure(
 463                                 fx.tcx,
 464                                 def_id,
 465                                 substs,
 466                                 ty::ClosureKind::FnOnce,
 467                             );
 468                             let func_ref = fx.get_function_ref(instance);
 469                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 470                             lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
 471                         }
 472                         _ => {
 473                             bug!("{} cannot be cast to a fn ptr", operand.layout().ty)
 474                         }
 475                     }
 476                 }
 477                 Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), operand, _ty) => {
 478                     let operand = trans_operand(fx, operand);
 479                     operand.unsize_value(fx, lval);
 480                 }
 481                 Rvalue::Discriminant(place) => {
 482                     let place = trans_place(fx, place);
 483                     let discr = trans_get_discriminant(fx, place, dest_layout);
 484                     lval.write_cvalue(fx, discr);
 485                 }
 486                 Rvalue::Repeat(operand, times) => {
 487                     let operand = trans_operand(fx, operand);
 488                     for i in 0..*times {
 489                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 490                         let to = lval.place_index(fx, index);
 491                         to.write_cvalue(fx, operand);
 492                     }
 493                 }
 494                 Rvalue::Len(place) => {
 495                     let place = trans_place(fx, place);
 496                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 497                     let len = codegen_array_len(fx, place);
 498                     lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
 499                 }
 500                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 501                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 502
 503                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 504                     let layout = fx.layout_of(content_ty);
 505                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 506                     let llalign = fx
 507                         .bcx
 508                         .ins()
 509                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 510                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 511
 512                     // Allocate space:
 513                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 514                         Ok(id) => id,
 515                         Err(s) => {
 516                             fx.tcx
 517                                 .sess
 518                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 519                         }
 520                     };
 521                     let instance = ty::Instance::mono(fx.tcx, def_id);
 522                     let func_ref = fx.get_function_ref(instance);
 523                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 524                     let ptr = fx.bcx.inst_results(call)[0];
 525                     lval.write_cvalue(fx, CValue::by_val(ptr, box_layout));
 526                 }
 527                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 528                     assert!(lval
 529                         .layout()
 530                         .ty
 531                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 532                     let ty_size = fx.layout_of(ty).size.bytes();
 533                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size.into());
 534                     lval.write_cvalue(fx, val);
 535                 }
 536                 Rvalue::Aggregate(kind, operands) => match **kind {
 537                     AggregateKind::Array(_ty) => {
 538                         for (i, operand) in operands.into_iter().enumerate() {
 539                             let operand = trans_operand(fx, operand);
 540                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 541                             let to = lval.place_index(fx, index);
 542                             to.write_cvalue(fx, operand);
 543                         }
 544                     }
 545                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 546                 },
 547             }
 548         }
 549         StatementKind::StorageLive(_)
 550         | StatementKind::StorageDead(_)
 551         | StatementKind::Nop
 552         | StatementKind::FakeRead(..)
 553         | StatementKind::Retag { .. }
 554         | StatementKind::AscribeUserType(..) => {}
 555
 556         StatementKind::InlineAsm(asm) => {
 557             use syntax::ast::Name;
 558             let InlineAsm { asm, outputs: _, inputs: _ } = &**asm;
 559             let rustc::hir::InlineAsm {
 560                 asm: asm_code, // Name
 561                 outputs, // Vec<Name>
 562                 inputs, // Vec<Name>
 563                 clobbers, // Vec<Name>
 564                 volatile, // bool
 565                 alignstack, // bool
 566                 dialect: _, // syntax::ast::AsmDialect
 567                 asm_str_style: _,
 568                 ctxt: _,
 569             } = asm;
 570             match &*asm_code.as_str() {
 571                 "cpuid" | "cpuid\n" => {
 572                     assert_eq!(inputs, &[Name::intern("{eax}"), Name::intern("{ecx}")]);
 573
 574                     assert_eq!(outputs.len(), 4);
 575                     for (i, c) in (&["={eax}", "={ebx}", "={ecx}", "={edx}"]).iter().enumerate() {
 576                         assert_eq!(&outputs[i].constraint.as_str(), c);
 577                         assert!(!outputs[i].is_rw);
 578                         assert!(!outputs[i].is_indirect);
 579                     }
 580
 581                     assert_eq!(clobbers, &[Name::intern("rbx")]);
 582
 583                     assert!(!volatile);
 584                     assert!(!alignstack);
 585
 586                     crate::trap::trap_unimplemented(fx, "__cpuid_count arch intrinsic is not supported");
 587                 }
 588                 "xgetbv" => {
 589                     assert_eq!(inputs, &[Name::intern("{ecx}")]);
 590
 591                     assert_eq!(outputs.len(), 2);
 592                     for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
 593                         assert_eq!(&outputs[i].constraint.as_str(), c);
 594                         assert!(!outputs[i].is_rw);
 595                         assert!(!outputs[i].is_indirect);
 596                     }
 597
 598                     assert_eq!(clobbers, &[]);
 599
 600                     assert!(!volatile);
 601                     assert!(!alignstack);
 602
 603                     crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
 604                 }
 605                 _ if fx.tcx.symbol_name(fx.instance).as_str() == "__rust_probestack" => {
 606                     crate::trap::trap_unimplemented(fx, "__rust_probestack is not supported");
 607                 }
 608                 _ => unimpl!("Inline assembly is not supported"),
 609             }
 610         }
 611     }
 612 }
 613
 614 fn codegen_array_len<'a, 'tcx: 'a>(
 615     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 616     place: CPlace<'tcx>,
 617 ) -> Value {
 618     match place.layout().ty.sty {
 619         ty::Array(_elem_ty, len) => {
 620             let len = crate::constant::force_eval_const(fx, len)
 621                 .eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64;
 622             fx.bcx.ins().iconst(fx.pointer_type, len)
 623         }
 624         ty::Slice(_elem_ty) => place
 625             .to_addr_maybe_unsized(fx)
 626             .1
 627             .expect("Length metadata for slice place"),
 628         _ => bug!("Rvalue::Len({:?})", place),
 629     }
 630 }
 631
 632 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 633     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 634     place: CPlace<'tcx>,
 635     dest_layout: TyLayout<'tcx>,
 636 ) -> CValue<'tcx> {
 637     let layout = place.layout();
 638
 639     if layout.abi == layout::Abi::Uninhabited {
 640         return trap_unreachable_ret_value(fx, dest_layout, "[panic] Tried to get discriminant for uninhabited type.");
 641     }
 642
 643     let (discr_scalar, discr_index, discr_kind) = match &layout.variants {
 644         layout::Variants::Single { index } => {
 645             let discr_val = layout
 646                 .ty
 647                 .ty_adt_def()
 648                 .map_or(index.as_u32() as u128, |def| {
 649                     def.discriminant_for_variant(fx.tcx, *index).val
 650                 });
 651             return CValue::const_val(fx, dest_layout.ty, discr_val);
 652         }
 653         layout::Variants::Multiple { discr, discr_index, discr_kind, variants: _ } => {
 654             (discr, *discr_index, discr_kind)
 655         }
 656     };
 657
 658     let discr = place.place_field(fx, mir::Field::new(discr_index)).to_cvalue(fx);
 659     let discr_ty = discr.layout().ty;
 660     let lldiscr = discr.load_scalar(fx);
 661     match discr_kind {
 662         layout::DiscriminantKind::Tag => {
 663             let signed = match discr_scalar.value {
 664                 layout::Int(_, signed) => signed,
 665                 _ => false,
 666             };
 667             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 668             return CValue::by_val(val, dest_layout);
 669         }
 670         layout::DiscriminantKind::Niche {
 671             dataful_variant,
 672             ref niche_variants,
 673             niche_start,
 674         } => {
 675             let niche_llty = fx.clif_type(discr_ty).unwrap();
 676             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 677             if niche_variants.start() == niche_variants.end() {
 678                 let b = fx
 679                     .bcx
 680                     .ins()
 681                     .icmp_imm(IntCC::Equal, lldiscr, *niche_start as u64 as i64);
 682                 let if_true = fx
 683                     .bcx
 684                     .ins()
 685                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 686                 let if_false = fx
 687                     .bcx
 688                     .ins()
 689                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 690                 let val = fx.bcx.ins().select(b, if_true, if_false);
 691                 return CValue::by_val(val, dest_layout);
 692             } else {
 693                 // Rebase from niche values to discriminant values.
 694                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 695                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 696                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 697                 let b = fx.bcx.ins().icmp_imm(
 698                     IntCC::UnsignedLessThanOrEqual,
 699                     lldiscr,
 700                     niche_variants.end().as_u32() as i64,
 701                 );
 702                 let if_true =
 703                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 704                 let if_false = fx
 705                     .bcx
 706                     .ins()
 707                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 708                 let val = fx.bcx.ins().select(b, if_true, if_false);
 709                 return CValue::by_val(val, dest_layout);
 710             }
 711         }
 712     }
 713 }
 714
 715 macro_rules! binop_match {
 716     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 717         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 718     };
 719     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 720         assert_eq!($fx.tcx.types.bool, $ret_ty);
 721         let ret_layout = $fx.layout_of($ret_ty);
 722
 723         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 724         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 725     }};
 726     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 727         assert_eq!($fx.tcx.types.bool, $ret_ty);
 728         let ret_layout = $fx.layout_of($ret_ty);
 729         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 730         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 731     }};
 732     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 733         $body
 734     }};
 735     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 736         let ret_layout = $fx.layout_of($ret_ty);
 737         CValue::by_val($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 738     }};
 739     (
 740         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 741         $(
 742             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 743         )*
 744     ) => {{
 745         let lhs = $lhs.load_scalar($fx);
 746         let rhs = $rhs.load_scalar($fx);
 747         match ($bin_op, $signed) {
 748             $(
 749                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 750             )*
 751         }
 752     }}
 753 }
 754
 755 fn trans_bool_binop<'a, 'tcx: 'a>(
 756     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 757     bin_op: BinOp,
 758     lhs: CValue<'tcx>,
 759     rhs: CValue<'tcx>,
 760 ) -> CValue<'tcx> {
 761     let res = binop_match! {
 762         fx, bin_op, false, lhs, rhs, fx.tcx.types.bool, "bool";
 763         Add (_) bug;
 764         Sub (_) bug;
 765         Mul (_) bug;
 766         Div (_) bug;
 767         Rem (_) bug;
 768         BitXor (_) bxor;
 769         BitAnd (_) band;
 770         BitOr (_) bor;
 771         Shl (_) bug;
 772         Shr (_) bug;
 773
 774         Eq (_) icmp(Equal);
 775         Lt (_) icmp(UnsignedLessThan);
 776         Le (_) icmp(UnsignedLessThanOrEqual);
 777         Ne (_) icmp(NotEqual);
 778         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 779         Gt (_) icmp(UnsignedGreaterThan);
 780
 781         Offset (_) bug;
 782     };
 783
 784     res
 785 }
 786
 787 pub fn trans_int_binop<'a, 'tcx: 'a>(
 788     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 789     bin_op: BinOp,
 790     lhs: CValue<'tcx>,
 791     rhs: CValue<'tcx>,
 792     out_ty: Ty<'tcx>,
 793     signed: bool,
 794 ) -> CValue<'tcx> {
 795     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 796         assert_eq!(
 797             lhs.layout().ty,
 798             rhs.layout().ty,
 799             "int binop requires lhs and rhs of same type"
 800         );
 801     }
 802
 803     match out_ty.sty {
 804         ty::Bool | ty::Uint(_) | ty::Int(_) => {}
 805         _ => unreachable!("Out ty {:?} is not an integer or bool", out_ty),
 806     }
 807
 808     if let Some(res) = crate::codegen_i128::maybe_codegen(fx, bin_op, false, signed, lhs, rhs, out_ty) {
 809         return res;
 810     }
 811
 812     binop_match! {
 813         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 814         Add (_) iadd;
 815         Sub (_) isub;
 816         Mul (_) imul;
 817         Div (false) udiv;
 818         Div (true) sdiv;
 819         Rem (false) urem;
 820         Rem (true) srem;
 821         BitXor (_) bxor;
 822         BitAnd (_) band;
 823         BitOr (_) bor;
 824         Shl (_) ishl;
 825         Shr (false) ushr;
 826         Shr (true) sshr;
 827
 828         Eq (_) icmp(Equal);
 829         Lt (false) icmp(UnsignedLessThan);
 830         Lt (true) icmp(SignedLessThan);
 831         Le (false) icmp(UnsignedLessThanOrEqual);
 832         Le (true) icmp(SignedLessThanOrEqual);
 833         Ne (_) icmp(NotEqual);
 834         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 835         Ge (true) icmp(SignedGreaterThanOrEqual);
 836         Gt (false) icmp(UnsignedGreaterThan);
 837         Gt (true) icmp(SignedGreaterThan);
 838
 839         Offset (_) bug;
 840     }
 841 }
 842
 843 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 844     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 845     bin_op: BinOp,
 846     in_lhs: CValue<'tcx>,
 847     in_rhs: CValue<'tcx>,
 848     out_ty: Ty<'tcx>,
 849     signed: bool,
 850 ) -> CValue<'tcx> {
 851     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 852         assert_eq!(
 853             in_lhs.layout().ty,
 854             in_rhs.layout().ty,
 855             "checked int binop requires lhs and rhs of same type"
 856         );
 857     }
 858
 859     let lhs = in_lhs.load_scalar(fx);
 860     let rhs = in_rhs.load_scalar(fx);
 861
 862     if let Some(res) = crate::codegen_i128::maybe_codegen(fx, bin_op, true, signed, in_lhs, in_rhs, out_ty) {
 863         return res;
 864     }
 865
 866     let (res, has_overflow) = match bin_op {
 867         BinOp::Add => {
 868             /*let (val, c_out) = fx.bcx.ins().iadd_cout(lhs, rhs);
 869             (val, c_out)*/
 870             // FIXME(CraneStation/cranelift#849) legalize iadd_cout for i8 and i16
 871             let val = fx.bcx.ins().iadd(lhs, rhs);
 872             let has_overflow = if !signed {
 873                 fx.bcx.ins().icmp(IntCC::UnsignedLessThan, val, lhs)
 874             } else {
 875                 let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 876                 let slt = fx.bcx.ins().icmp(IntCC::SignedLessThan, val, lhs);
 877                 fx.bcx.ins().bxor(rhs_is_negative, slt)
 878             };
 879             (val, has_overflow)
 880         }
 881         BinOp::Sub => {
 882             /*let (val, b_out) = fx.bcx.ins().isub_bout(lhs, rhs);
 883             (val, b_out)*/
 884             // FIXME(CraneStation/cranelift#849) legalize isub_bout for i8 and i16
 885             let val = fx.bcx.ins().isub(lhs, rhs);
 886             let has_overflow = if !signed {
 887                 fx.bcx.ins().icmp(IntCC::UnsignedGreaterThan, val, lhs)
 888             } else {
 889                 let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 890                 let sgt = fx.bcx.ins().icmp(IntCC::SignedGreaterThan, val, lhs);
 891                 fx.bcx.ins().bxor(rhs_is_negative, sgt)
 892             };
 893             (val, has_overflow)
 894         }
 895         BinOp::Mul => {
 896             let val = fx.bcx.ins().imul(lhs, rhs);
 897             /*let val_hi = if !signed {
 898                 fx.bcx.ins().umulhi(lhs, rhs)
 899             } else {
 900                 fx.bcx.ins().smulhi(lhs, rhs)
 901             };
 902             let has_overflow = fx.bcx.ins().icmp_imm(IntCC::NotEqual, val_hi, 0);*/
 903             // TODO: check for overflow
 904             let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 905             (val, has_overflow)
 906         }
 907         BinOp::Shl => {
 908             let val = fx.bcx.ins().ishl(lhs, rhs);
 909             // TODO: check for overflow
 910             let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 911             (val, has_overflow)
 912         }
 913         BinOp::Shr => {
 914             let val = if !signed {
 915                 fx.bcx.ins().ushr(lhs, rhs)
 916             } else {
 917                 fx.bcx.ins().sshr(lhs, rhs)
 918             };
 919             // TODO: check for overflow
 920             let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 921             (val, has_overflow)
 922         }
 923         _ => bug!(
 924             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 925             bin_op,
 926             in_lhs,
 927             in_rhs
 928         ),
 929     };
 930
 931     let has_overflow = fx.bcx.ins().bint(types::I8, has_overflow);
 932     let out_place = CPlace::new_stack_slot(fx, out_ty);
 933     let out_layout = out_place.layout();
 934     out_place.write_cvalue(fx, CValue::by_val_pair(res, has_overflow, out_layout));
 935
 936     out_place.to_cvalue(fx)
 937 }
 938
 939 fn trans_float_binop<'a, 'tcx: 'a>(
 940     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 941     bin_op: BinOp,
 942     lhs: CValue<'tcx>,
 943     rhs: CValue<'tcx>,
 944     ty: Ty<'tcx>,
 945 ) -> CValue<'tcx> {
 946     let res = binop_match! {
 947         fx, bin_op, false, lhs, rhs, ty, "float";
 948         Add (_) fadd;
 949         Sub (_) fsub;
 950         Mul (_) fmul;
 951         Div (_) fdiv;
 952         Rem (_) custom(|| {
 953             assert_eq!(lhs.layout().ty, ty);
 954             assert_eq!(rhs.layout().ty, ty);
 955             match ty.sty {
 956                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
 957                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
 958                 _ => bug!(),
 959             }
 960         });
 961         BitXor (_) bxor;
 962         BitAnd (_) band;
 963         BitOr (_) bor;
 964         Shl (_) bug;
 965         Shr (_) bug;
 966
 967         Eq (_) fcmp(Equal);
 968         Lt (_) fcmp(LessThan);
 969         Le (_) fcmp(LessThanOrEqual);
 970         Ne (_) fcmp(NotEqual);
 971         Ge (_) fcmp(GreaterThanOrEqual);
 972         Gt (_) fcmp(GreaterThan);
 973
 974         Offset (_) bug;
 975     };
 976
 977     res
 978 }
 979
 980 fn trans_char_binop<'a, 'tcx: 'a>(
 981     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 982     bin_op: BinOp,
 983     lhs: CValue<'tcx>,
 984     rhs: CValue<'tcx>,
 985     ty: Ty<'tcx>,
 986 ) -> CValue<'tcx> {
 987     let res = binop_match! {
 988         fx, bin_op, false, lhs, rhs, ty, "char";
 989         Add (_) bug;
 990         Sub (_) bug;
 991         Mul (_) bug;
 992         Div (_) bug;
 993         Rem (_) bug;
 994         BitXor (_) bug;
 995         BitAnd (_) bug;
 996         BitOr (_) bug;
 997         Shl (_) bug;
 998         Shr (_) bug;
 999
1000         Eq (_) icmp(Equal);
1001         Lt (_) icmp(UnsignedLessThan);
1002         Le (_) icmp(UnsignedLessThanOrEqual);
1003         Ne (_) icmp(NotEqual);
1004         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1005         Gt (_) icmp(UnsignedGreaterThan);
1006
1007         Offset (_) bug;
1008     };
1009
1010     res
1011 }
1012
1013 fn trans_ptr_binop<'a, 'tcx: 'a>(
1014     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1015     bin_op: BinOp,
1016     lhs: CValue<'tcx>,
1017     rhs: CValue<'tcx>,
1018     ret_ty: Ty<'tcx>,
1019 ) -> CValue<'tcx> {
1020     let not_fat = match lhs.layout().ty.sty {
1021         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1022             ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
1023         }
1024         ty::FnPtr(..) => true,
1025         _ => bug!("trans_ptr_binop on non ptr"),
1026     };
1027     if not_fat {
1028         if let BinOp::Offset = bin_op {
1029             let (base, offset) = (lhs, rhs.load_scalar(fx));
1030             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
1031             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
1032             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
1033             let base_val = base.load_scalar(fx);
1034             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
1035             return CValue::by_val(res, base.layout());
1036         }
1037
1038         binop_match! {
1039             fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1040             Add (_) bug;
1041             Sub (_) bug;
1042             Mul (_) bug;
1043             Div (_) bug;
1044             Rem (_) bug;
1045             BitXor (_) bug;
1046             BitAnd (_) bug;
1047             BitOr (_) bug;
1048             Shl (_) bug;
1049             Shr (_) bug;
1050
1051             Eq (_) icmp(Equal);
1052             Lt (_) icmp(UnsignedLessThan);
1053             Le (_) icmp(UnsignedLessThanOrEqual);
1054             Ne (_) icmp(NotEqual);
1055             Ge (_) icmp(UnsignedGreaterThanOrEqual);
1056             Gt (_) icmp(UnsignedGreaterThan);
1057
1058             Offset (_) bug; // Handled above
1059         }
1060     } else {
1061         let (lhs_ptr, lhs_extra) = lhs.load_scalar_pair(fx);
1062         let (rhs_ptr, rhs_extra) = rhs.load_scalar_pair(fx);
1063
1064         let res = match bin_op {
1065             BinOp::Eq => {
1066                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1067                 let extra_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_extra, rhs_extra);
1068                 fx.bcx.ins().band(ptr_eq, extra_eq)
1069             }
1070             BinOp::Ne => {
1071                 let ptr_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_ptr, rhs_ptr);
1072                 let extra_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_extra, rhs_extra);
1073                 fx.bcx.ins().bor(ptr_ne, extra_ne)
1074             }
1075             BinOp::Lt | BinOp::Le | BinOp::Ge | BinOp::Gt => {
1076                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1077
1078                 let ptr_cmp = fx.bcx.ins().icmp(match bin_op {
1079                     BinOp::Lt => IntCC::UnsignedLessThan,
1080                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1081                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1082                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1083                     _ => unreachable!(),
1084                 }, lhs_ptr, rhs_ptr);
1085
1086                 let extra_cmp = fx.bcx.ins().icmp(match bin_op {
1087                     BinOp::Lt => IntCC::UnsignedLessThan,
1088                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1089                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1090                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1091                     _ => unreachable!(),
1092                 }, lhs_extra, rhs_extra);
1093
1094                 fx.bcx.ins().select(ptr_eq, extra_cmp, ptr_cmp)
1095             }
1096             _ => panic!("bin_op {:?} on ptr", bin_op),
1097         };
1098
1099         assert_eq!(fx.tcx.types.bool, ret_ty);
1100         let ret_layout = fx.layout_of(ret_ty);
1101         CValue::by_val(fx.bcx.ins().bint(types::I8, res), ret_layout)
1102     }
1103 }
1104
1105 pub fn trans_place<'a, 'tcx: 'a>(
1106     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1107     place: &Place<'tcx>,
1108 ) -> CPlace<'tcx> {
1109     let base = match &place.base {
1110         PlaceBase::Local(local) => fx.get_local_place(*local),
1111         PlaceBase::Static(static_) => match static_.kind {
1112             StaticKind::Static(def_id) => {
1113                 crate::constant::codegen_static_ref(fx, def_id, static_.ty)
1114             }
1115             StaticKind::Promoted(promoted) => {
1116                 crate::constant::trans_promoted(fx, promoted, static_.ty)
1117             }
1118         }
1119     };
1120
1121     trans_place_projection(fx, base, &place.projection)
1122 }
1123
1124 pub fn trans_place_projection<'a, 'tcx: 'a>(
1125     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1126     base: CPlace<'tcx>,
1127     projection: &Option<Box<Projection<'tcx>>>,
1128 ) -> CPlace<'tcx> {
1129     let projection = if let Some(projection) = projection {
1130         projection
1131     } else {
1132         return base;
1133     };
1134
1135     let base = trans_place_projection(fx, base, &projection.base);
1136
1137     match projection.elem {
1138         ProjectionElem::Deref => base.place_deref(fx),
1139         ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1140         ProjectionElem::Index(local) => {
1141             let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1142             base.place_index(fx, index)
1143         }
1144         ProjectionElem::ConstantIndex {
1145             offset,
1146             min_length: _,
1147             from_end,
1148         } => {
1149             let index = if !from_end {
1150                 fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1151             } else {
1152                 let len = codegen_array_len(fx, base);
1153                 fx.bcx.ins().iadd_imm(len, -(offset as i64))
1154             };
1155             base.place_index(fx, index)
1156         }
1157         ProjectionElem::Subslice { from, to } => {
1158             // These indices are generated by slice patterns.
1159             // slice[from:-to] in Python terms.
1160
1161             match base.layout().ty.sty {
1162                 ty::Array(elem_ty, len) => {
1163                     let elem_layout = fx.layout_of(elem_ty);
1164                     let ptr = base.to_addr(fx);
1165                     let len = crate::constant::force_eval_const(fx, len)
1166                         .eval_usize(fx.tcx, ParamEnv::reveal_all());
1167                     CPlace::for_addr(
1168                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1169                         fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
1170                     )
1171                 }
1172                 ty::Slice(elem_ty) => {
1173                     let elem_layout = fx.layout_of(elem_ty);
1174                     let (ptr, len) = base.to_addr_maybe_unsized(fx);
1175                     let len = len.unwrap();
1176                     CPlace::for_addr_with_extra(
1177                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1178                         fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
1179                         base.layout(),
1180                     )
1181                 }
1182                 _ => unreachable!(),
1183             }
1184         }
1185         ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1186     }
1187 }
1188
1189 pub fn trans_operand<'a, 'tcx>(
1190     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1191     operand: &Operand<'tcx>,
1192 ) -> CValue<'tcx> {
1193     match operand {
1194         Operand::Move(place) | Operand::Copy(place) => {
1195             let cplace = trans_place(fx, place);
1196             cplace.to_cvalue(fx)
1197         }
1198         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1199     }
1200 }