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 {:?} failed at {:?}.", 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 as u64 as i64);
 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 as u64 as i64)
 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 res = match ty.sty {
 338                         ty::Uint(_) => {
 339                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 340                         }
 341                         ty::Int(_) => {
 342                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 343                         }
 344                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 345                     };
 346                     lval.write_cvalue(fx, res);
 347                 }
 348                 Rvalue::UnaryOp(un_op, operand) => {
 349                     let operand = trans_operand(fx, operand);
 350                     let layout = operand.layout();
 351                     let val = operand.load_scalar(fx);
 352                     let res = match un_op {
 353                         UnOp::Not => {
 354                             match layout.ty.sty {
 355                                 ty::Bool => {
 356                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 357                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 358                                     fx.bcx.ins().bint(types::I8, res)
 359                                 }
 360                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 361                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 362                             }
 363                         }
 364                         UnOp::Neg => match layout.ty.sty {
 365                             ty::Int(_) => {
 366                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 367                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 368                                 fx.bcx.ins().isub(zero, val)
 369                             }
 370                             ty::Float(_) => fx.bcx.ins().fneg(val),
 371                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 372                         },
 373                     };
 374                     lval.write_cvalue(fx, CValue::by_val(res, layout));
 375                 }
 376                 Rvalue::Cast(CastKind::Pointer(PointerCast::ReifyFnPointer), operand, ty) => {
 377                     let layout = fx.layout_of(ty);
 378                     match fx
 379                         .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
 380                         .sty
 381                     {
 382                         ty::FnDef(def_id, substs) => {
 383                             let func_ref = fx.get_function_ref(
 384                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
 385                                     .unwrap(),
 386                             );
 387                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 388                             lval.write_cvalue(fx, CValue::by_val(func_addr, layout));
 389                         }
 390                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 391                     }
 392                 }
 393                 Rvalue::Cast(CastKind::Pointer(PointerCast::UnsafeFnPointer), operand, ty)
 394                 | Rvalue::Cast(CastKind::Pointer(PointerCast::MutToConstPointer), operand, ty) => {
 395                     let operand = trans_operand(fx, operand);
 396                     let layout = fx.layout_of(ty);
 397                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 398                 }
 399                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 400                     let operand = trans_operand(fx, operand);
 401                     let from_ty = operand.layout().ty;
 402
 403                     fn is_fat_ptr<'a, 'tcx: 'a>(fx: &FunctionCx<'a, 'tcx, impl Backend>, ty: Ty<'tcx>) -> bool {
 404                         ty
 405                             .builtin_deref(true)
 406                             .map(|ty::TypeAndMut {ty: pointee_ty, mutbl: _ }| fx.layout_of(pointee_ty).is_unsized())
 407                             .unwrap_or(false)
 408                     }
 409
 410                     if is_fat_ptr(fx, from_ty) {
 411                         if is_fat_ptr(fx, to_ty) {
 412                             // fat-ptr -> fat-ptr
 413                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 414                         } else {
 415                             // fat-ptr -> thin-ptr
 416                             let (ptr, _extra) = operand.load_scalar_pair(fx);
 417                             lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
 418                         }
 419                     } else if let ty::Adt(adt_def, _substs) = from_ty.sty {
 420                         // enum -> discriminant value
 421                         assert!(adt_def.is_enum());
 422                         match to_ty.sty {
 423                             ty::Uint(_) | ty::Int(_) => {},
 424                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
 425                         }
 426
 427                         // FIXME avoid forcing to stack
 428                         let place =
 429                             CPlace::for_addr(operand.force_stack(fx), operand.layout());
 430                         let discr = trans_get_discriminant(fx, place, fx.layout_of(to_ty));
 431                         lval.write_cvalue(fx, discr);
 432                     } else {
 433                         let from_clif_ty = fx.clif_type(from_ty).unwrap();
 434                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
 435                         let from = operand.load_scalar(fx);
 436
 437                         let signed = match from_ty.sty {
 438                             ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 439                             ty::Int(..) => true,
 440                             ty::Float(..) => false, // `signed` is unused for floats
 441                             _ => panic!("{}", from_ty),
 442                         };
 443
 444                         let res = if from_clif_ty.is_int() && to_clif_ty.is_int() {
 445                             // int-like -> int-like
 446                             crate::common::clif_intcast(
 447                                 fx,
 448                                 from,
 449                                 to_clif_ty,
 450                                 signed,
 451                             )
 452                         } else if from_clif_ty.is_int() && to_clif_ty.is_float() {
 453                             // int-like -> float
 454                             if signed {
 455                                 fx.bcx.ins().fcvt_from_sint(to_clif_ty, from)
 456                             } else {
 457                                 fx.bcx.ins().fcvt_from_uint(to_clif_ty, from)
 458                             }
 459                         } else if from_clif_ty.is_float() && to_clif_ty.is_int() {
 460                             // float -> int-like
 461                             let from = operand.load_scalar(fx);
 462                             if signed {
 463                                 fx.bcx.ins().fcvt_to_sint_sat(to_clif_ty, from)
 464                             } else {
 465                                 fx.bcx.ins().fcvt_to_uint_sat(to_clif_ty, from)
 466                             }
 467                         } else if from_clif_ty.is_float() && to_clif_ty.is_float() {
 468                             // float -> float
 469                             match (from_clif_ty, to_clif_ty) {
 470                                 (types::F32, types::F64) => {
 471                                     fx.bcx.ins().fpromote(types::F64, from)
 472                                 }
 473                                 (types::F64, types::F32) => {
 474                                     fx.bcx.ins().fdemote(types::F32, from)
 475                                 }
 476                                 _ => from,
 477                             }
 478                         } else {
 479                             unimpl!("rval misc {:?} {:?}", from_ty, to_ty)
 480                         };
 481                         lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
 482                     }
 483                 }
 484                 Rvalue::Cast(CastKind::Pointer(PointerCast::ClosureFnPointer(_)), operand, _ty) => {
 485                     let operand = trans_operand(fx, operand);
 486                     match operand.layout().ty.sty {
 487                         ty::Closure(def_id, substs) => {
 488                             let instance = Instance::resolve_closure(
 489                                 fx.tcx,
 490                                 def_id,
 491                                 substs,
 492                                 ty::ClosureKind::FnOnce,
 493                             );
 494                             let func_ref = fx.get_function_ref(instance);
 495                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 496                             lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
 497                         }
 498                         _ => {
 499                             bug!("{} cannot be cast to a fn ptr", operand.layout().ty)
 500                         }
 501                     }
 502                 }
 503                 Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), operand, _ty) => {
 504                     let operand = trans_operand(fx, operand);
 505                     operand.unsize_value(fx, lval);
 506                 }
 507                 Rvalue::Discriminant(place) => {
 508                     let place = trans_place(fx, place);
 509                     let discr = trans_get_discriminant(fx, place, dest_layout);
 510                     lval.write_cvalue(fx, discr);
 511                 }
 512                 Rvalue::Repeat(operand, times) => {
 513                     let operand = trans_operand(fx, operand);
 514                     for i in 0..*times {
 515                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 516                         let to = lval.place_index(fx, index);
 517                         to.write_cvalue(fx, operand);
 518                     }
 519                 }
 520                 Rvalue::Len(place) => {
 521                     let place = trans_place(fx, place);
 522                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 523                     let len = codegen_array_len(fx, place);
 524                     lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
 525                 }
 526                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 527                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 528
 529                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 530                     let layout = fx.layout_of(content_ty);
 531                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 532                     let llalign = fx
 533                         .bcx
 534                         .ins()
 535                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 536                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 537
 538                     // Allocate space:
 539                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 540                         Ok(id) => id,
 541                         Err(s) => {
 542                             fx.tcx
 543                                 .sess
 544                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 545                         }
 546                     };
 547                     let instance = ty::Instance::mono(fx.tcx, def_id);
 548                     let func_ref = fx.get_function_ref(instance);
 549                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 550                     let ptr = fx.bcx.inst_results(call)[0];
 551                     lval.write_cvalue(fx, CValue::by_val(ptr, box_layout));
 552                 }
 553                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 554                     assert!(lval
 555                         .layout()
 556                         .ty
 557                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 558                     let ty_size = fx.layout_of(ty).size.bytes();
 559                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 560                     lval.write_cvalue(fx, val);
 561                 }
 562                 Rvalue::Aggregate(kind, operands) => match **kind {
 563                     AggregateKind::Array(_ty) => {
 564                         for (i, operand) in operands.into_iter().enumerate() {
 565                             let operand = trans_operand(fx, operand);
 566                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 567                             let to = lval.place_index(fx, index);
 568                             to.write_cvalue(fx, operand);
 569                         }
 570                     }
 571                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 572                 },
 573             }
 574         }
 575         StatementKind::StorageLive(_)
 576         | StatementKind::StorageDead(_)
 577         | StatementKind::Nop
 578         | StatementKind::FakeRead(..)
 579         | StatementKind::Retag { .. }
 580         | StatementKind::AscribeUserType(..) => {}
 581
 582         StatementKind::InlineAsm(asm) => {
 583             use syntax::ast::Name;
 584             let InlineAsm { asm, outputs: _, inputs: _ } = &**asm;
 585             let rustc::hir::InlineAsm {
 586                 asm: asm_code, // Name
 587                 outputs, // Vec<Name>
 588                 inputs, // Vec<Name>
 589                 clobbers, // Vec<Name>
 590                 volatile, // bool
 591                 alignstack, // bool
 592                 dialect: _, // syntax::ast::AsmDialect
 593                 asm_str_style: _,
 594                 ctxt: _,
 595             } = asm;
 596             match &*asm_code.as_str() {
 597                 "cpuid" | "cpuid\n" => {
 598                     assert_eq!(inputs, &[Name::intern("{eax}"), Name::intern("{ecx}")]);
 599
 600                     assert_eq!(outputs.len(), 4);
 601                     for (i, c) in (&["={eax}", "={ebx}", "={ecx}", "={edx}"]).iter().enumerate() {
 602                         assert_eq!(&outputs[i].constraint.as_str(), c);
 603                         assert!(!outputs[i].is_rw);
 604                         assert!(!outputs[i].is_indirect);
 605                     }
 606
 607                     assert_eq!(clobbers, &[Name::intern("rbx")]);
 608
 609                     assert!(!volatile);
 610                     assert!(!alignstack);
 611
 612                     crate::trap::trap_unimplemented(fx, "__cpuid_count arch intrinsic is not supported");
 613                 }
 614                 "xgetbv" => {
 615                     assert_eq!(inputs, &[Name::intern("{ecx}")]);
 616
 617                     assert_eq!(outputs.len(), 2);
 618                     for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
 619                         assert_eq!(&outputs[i].constraint.as_str(), c);
 620                         assert!(!outputs[i].is_rw);
 621                         assert!(!outputs[i].is_indirect);
 622                     }
 623
 624                     assert_eq!(clobbers, &[]);
 625
 626                     assert!(!volatile);
 627                     assert!(!alignstack);
 628
 629                     crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
 630                 }
 631                 _ if fx.tcx.symbol_name(fx.instance).as_str() == "__rust_probestack" => {
 632                     crate::trap::trap_unimplemented(fx, "__rust_probestack is not supported");
 633                 }
 634                 _ => unimpl!("Inline assembly is not supported"),
 635             }
 636         }
 637     }
 638 }
 639
 640 fn codegen_array_len<'a, 'tcx: 'a>(
 641     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 642     place: CPlace<'tcx>,
 643 ) -> Value {
 644     match place.layout().ty.sty {
 645         ty::Array(_elem_ty, len) => {
 646             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx) as i64;
 647             fx.bcx.ins().iconst(fx.pointer_type, len)
 648         }
 649         ty::Slice(_elem_ty) => place
 650             .to_addr_maybe_unsized(fx)
 651             .1
 652             .expect("Length metadata for slice place"),
 653         _ => bug!("Rvalue::Len({:?})", place),
 654     }
 655 }
 656
 657 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 658     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 659     place: CPlace<'tcx>,
 660     dest_layout: TyLayout<'tcx>,
 661 ) -> CValue<'tcx> {
 662     let layout = place.layout();
 663
 664     if layout.abi == layout::Abi::Uninhabited {
 665         return trap_unreachable_ret_value(fx, dest_layout, "[panic] Tried to get discriminant for uninhabited type.");
 666     }
 667
 668     let (discr_scalar, discr_index, discr_kind) = match &layout.variants {
 669         layout::Variants::Single { index } => {
 670             let discr_val = layout
 671                 .ty
 672                 .ty_adt_def()
 673                 .map_or(index.as_u32() as u128, |def| {
 674                     def.discriminant_for_variant(fx.tcx, *index).val
 675                 });
 676             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 677         }
 678         layout::Variants::Multiple { discr, discr_index, discr_kind, variants: _ } => {
 679             (discr, *discr_index, discr_kind)
 680         }
 681     };
 682
 683     let discr = place.place_field(fx, mir::Field::new(discr_index)).to_cvalue(fx);
 684     let discr_ty = discr.layout().ty;
 685     let lldiscr = discr.load_scalar(fx);
 686     match discr_kind {
 687         layout::DiscriminantKind::Tag => {
 688             let signed = match discr_scalar.value {
 689                 layout::Int(_, signed) => signed,
 690                 _ => false,
 691             };
 692             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 693             return CValue::by_val(val, dest_layout);
 694         }
 695         layout::DiscriminantKind::Niche {
 696             dataful_variant,
 697             ref niche_variants,
 698             niche_start,
 699         } => {
 700             let niche_llty = fx.clif_type(discr_ty).unwrap();
 701             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 702             if niche_variants.start() == niche_variants.end() {
 703                 let b = fx
 704                     .bcx
 705                     .ins()
 706                     .icmp_imm(IntCC::Equal, lldiscr, *niche_start as u64 as i64);
 707                 let if_true = fx
 708                     .bcx
 709                     .ins()
 710                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 711                 let if_false = fx
 712                     .bcx
 713                     .ins()
 714                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 715                 let val = fx.bcx.ins().select(b, if_true, if_false);
 716                 return CValue::by_val(val, dest_layout);
 717             } else {
 718                 // Rebase from niche values to discriminant values.
 719                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 720                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 721                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 722                 let b = fx.bcx.ins().icmp_imm(
 723                     IntCC::UnsignedLessThanOrEqual,
 724                     lldiscr,
 725                     niche_variants.end().as_u32() as i64,
 726                 );
 727                 let if_true =
 728                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 729                 let if_false = fx
 730                     .bcx
 731                     .ins()
 732                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 733                 let val = fx.bcx.ins().select(b, if_true, if_false);
 734                 return CValue::by_val(val, dest_layout);
 735             }
 736         }
 737     }
 738 }
 739
 740 macro_rules! binop_match {
 741     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 742         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 743     };
 744     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 745         assert_eq!($fx.tcx.types.bool, $ret_ty);
 746         let ret_layout = $fx.layout_of($ret_ty);
 747
 748         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 749         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 750     }};
 751     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 752         assert_eq!($fx.tcx.types.bool, $ret_ty);
 753         let ret_layout = $fx.layout_of($ret_ty);
 754         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 755         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 756     }};
 757     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 758         $body
 759     }};
 760     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 761         let ret_layout = $fx.layout_of($ret_ty);
 762         CValue::by_val($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 763     }};
 764     (
 765         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 766         $(
 767             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 768         )*
 769     ) => {{
 770         let lhs = $lhs.load_scalar($fx);
 771         let rhs = $rhs.load_scalar($fx);
 772         match ($bin_op, $signed) {
 773             $(
 774                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 775             )*
 776         }
 777     }}
 778 }
 779
 780 fn trans_bool_binop<'a, 'tcx: 'a>(
 781     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 782     bin_op: BinOp,
 783     lhs: CValue<'tcx>,
 784     rhs: CValue<'tcx>,
 785 ) -> CValue<'tcx> {
 786     let res = binop_match! {
 787         fx, bin_op, false, lhs, rhs, fx.tcx.types.bool, "bool";
 788         Add (_) bug;
 789         Sub (_) bug;
 790         Mul (_) bug;
 791         Div (_) bug;
 792         Rem (_) bug;
 793         BitXor (_) bxor;
 794         BitAnd (_) band;
 795         BitOr (_) bor;
 796         Shl (_) bug;
 797         Shr (_) bug;
 798
 799         Eq (_) icmp(Equal);
 800         Lt (_) icmp(UnsignedLessThan);
 801         Le (_) icmp(UnsignedLessThanOrEqual);
 802         Ne (_) icmp(NotEqual);
 803         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 804         Gt (_) icmp(UnsignedGreaterThan);
 805
 806         Offset (_) bug;
 807     };
 808
 809     res
 810 }
 811
 812 pub fn trans_int_binop<'a, 'tcx: 'a>(
 813     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 814     bin_op: BinOp,
 815     lhs: CValue<'tcx>,
 816     rhs: CValue<'tcx>,
 817     out_ty: Ty<'tcx>,
 818     signed: bool,
 819 ) -> CValue<'tcx> {
 820     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 821         assert_eq!(
 822             lhs.layout().ty,
 823             rhs.layout().ty,
 824             "int binop requires lhs and rhs of same type"
 825         );
 826     }
 827
 828     if lhs.layout().ty == fx.tcx.types.u128 || lhs.layout().ty == fx.tcx.types.i128 {
 829         return match (bin_op, signed) {
 830             _ => {
 831                 let layout = fx.layout_of(out_ty);
 832                 let a = fx.bcx.ins().iconst(types::I64, 42);
 833                 let b = fx.bcx.ins().iconst(types::I64, 0);
 834                 let val = fx.bcx.ins().iconcat(a, b);
 835                 CValue::by_val(val, layout)
 836             }
 837         }
 838     }
 839
 840     binop_match! {
 841         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 842         Add (_) iadd;
 843         Sub (_) isub;
 844         Mul (_) imul;
 845         Div (false) udiv;
 846         Div (true) sdiv;
 847         Rem (false) urem;
 848         Rem (true) srem;
 849         BitXor (_) bxor;
 850         BitAnd (_) band;
 851         BitOr (_) bor;
 852         Shl (_) ishl;
 853         Shr (false) ushr;
 854         Shr (true) sshr;
 855
 856         Eq (_) icmp(Equal);
 857         Lt (false) icmp(UnsignedLessThan);
 858         Lt (true) icmp(SignedLessThan);
 859         Le (false) icmp(UnsignedLessThanOrEqual);
 860         Le (true) icmp(SignedLessThanOrEqual);
 861         Ne (_) icmp(NotEqual);
 862         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 863         Ge (true) icmp(SignedGreaterThanOrEqual);
 864         Gt (false) icmp(UnsignedGreaterThan);
 865         Gt (true) icmp(SignedGreaterThan);
 866
 867         Offset (_) bug;
 868     }
 869 }
 870
 871 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 872     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 873     bin_op: BinOp,
 874     in_lhs: CValue<'tcx>,
 875     in_rhs: CValue<'tcx>,
 876     out_ty: Ty<'tcx>,
 877     signed: bool,
 878 ) -> CValue<'tcx> {
 879     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 880         assert_eq!(
 881             in_lhs.layout().ty,
 882             in_rhs.layout().ty,
 883             "checked int binop requires lhs and rhs of same type"
 884         );
 885     }
 886
 887     let lhs = in_lhs.load_scalar(fx);
 888     let rhs = in_rhs.load_scalar(fx);
 889     let (res, has_overflow) = if in_lhs.layout().ty == fx.tcx.types.u128 || in_lhs.layout().ty == fx.tcx.types.i128 {
 890         match (bin_op, signed) {
 891             _ => {
 892                 let a = fx.bcx.ins().iconst(types::I64, 42);
 893                 let b = fx.bcx.ins().iconst(types::I64, 0);
 894                 (fx.bcx.ins().iconcat(a, b), fx.bcx.ins().bconst(types::B1, false))
 895             }
 896         }
 897     } else {
 898         match bin_op {
 899             BinOp::Add => {
 900                 /*let (val, c_out) = fx.bcx.ins().iadd_cout(lhs, rhs);
 901                 (val, c_out)*/
 902                 // FIXME(CraneStation/cranelift#849) legalize iadd_cout for i8 and i16
 903                 let val = fx.bcx.ins().iadd(lhs, rhs);
 904                 let has_overflow = if !signed {
 905                     fx.bcx.ins().icmp(IntCC::UnsignedLessThan, val, lhs)
 906                 } else {
 907                     let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 908                     let slt = fx.bcx.ins().icmp(IntCC::SignedLessThan, val, lhs);
 909                     fx.bcx.ins().bxor(rhs_is_negative, slt)
 910                 };
 911                 (val, has_overflow)
 912             }
 913             BinOp::Sub => {
 914                 /*let (val, b_out) = fx.bcx.ins().isub_bout(lhs, rhs);
 915                 (val, b_out)*/
 916                 // FIXME(CraneStation/cranelift#849) legalize isub_bout for i8 and i16
 917                 let val = fx.bcx.ins().isub(lhs, rhs);
 918                 let has_overflow = if !signed {
 919                     fx.bcx.ins().icmp(IntCC::UnsignedGreaterThan, val, lhs)
 920                 } else {
 921                     let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 922                     let sgt = fx.bcx.ins().icmp(IntCC::SignedGreaterThan, val, lhs);
 923                     fx.bcx.ins().bxor(rhs_is_negative, sgt)
 924                 };
 925                 (val, has_overflow)
 926             }
 927             BinOp::Mul => {
 928                 let val = fx.bcx.ins().imul(lhs, rhs);
 929                 /*let val_hi = if !signed {
 930                     fx.bcx.ins().umulhi(lhs, rhs)
 931                 } else {
 932                     fx.bcx.ins().smulhi(lhs, rhs)
 933                 };
 934                 let has_overflow = fx.bcx.ins().icmp_imm(IntCC::NotEqual, val_hi, 0);*/
 935                 // TODO: check for overflow
 936                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 937                 (val, has_overflow)
 938             }
 939             BinOp::Shl => {
 940                 let val = fx.bcx.ins().ishl(lhs, rhs);
 941                 // TODO: check for overflow
 942                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 943                 (val, has_overflow)
 944             }
 945             BinOp::Shr => {
 946                 let val = if !signed {
 947                     fx.bcx.ins().ushr(lhs, rhs)
 948                 } else {
 949                     fx.bcx.ins().sshr(lhs, rhs)
 950                 };
 951                 // TODO: check for overflow
 952                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 953                 (val, has_overflow)
 954             }
 955             _ => bug!(
 956                 "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 957                 bin_op,
 958                 in_lhs,
 959                 in_rhs
 960             ),
 961         }
 962     };
 963
 964     let has_overflow = fx.bcx.ins().bint(types::I8, has_overflow);
 965     let out_place = CPlace::new_stack_slot(fx, out_ty);
 966     let out_layout = out_place.layout();
 967     out_place.write_cvalue(fx, CValue::by_val_pair(res, has_overflow, out_layout));
 968
 969     out_place.to_cvalue(fx)
 970 }
 971
 972 fn trans_float_binop<'a, 'tcx: 'a>(
 973     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 974     bin_op: BinOp,
 975     lhs: CValue<'tcx>,
 976     rhs: CValue<'tcx>,
 977     ty: Ty<'tcx>,
 978 ) -> CValue<'tcx> {
 979     let res = binop_match! {
 980         fx, bin_op, false, lhs, rhs, ty, "float";
 981         Add (_) fadd;
 982         Sub (_) fsub;
 983         Mul (_) fmul;
 984         Div (_) fdiv;
 985         Rem (_) custom(|| {
 986             assert_eq!(lhs.layout().ty, ty);
 987             assert_eq!(rhs.layout().ty, ty);
 988             match ty.sty {
 989                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
 990                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
 991                 _ => bug!(),
 992             }
 993         });
 994         BitXor (_) bxor;
 995         BitAnd (_) band;
 996         BitOr (_) bor;
 997         Shl (_) bug;
 998         Shr (_) bug;
 999
1000         Eq (_) fcmp(Equal);
1001         Lt (_) fcmp(LessThan);
1002         Le (_) fcmp(LessThanOrEqual);
1003         Ne (_) fcmp(NotEqual);
1004         Ge (_) fcmp(GreaterThanOrEqual);
1005         Gt (_) fcmp(GreaterThan);
1006
1007         Offset (_) bug;
1008     };
1009
1010     res
1011 }
1012
1013 fn trans_char_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     ty: Ty<'tcx>,
1019 ) -> CValue<'tcx> {
1020     let res = binop_match! {
1021         fx, bin_op, false, lhs, rhs, ty, "char";
1022         Add (_) bug;
1023         Sub (_) bug;
1024         Mul (_) bug;
1025         Div (_) bug;
1026         Rem (_) bug;
1027         BitXor (_) bug;
1028         BitAnd (_) bug;
1029         BitOr (_) bug;
1030         Shl (_) bug;
1031         Shr (_) bug;
1032
1033         Eq (_) icmp(Equal);
1034         Lt (_) icmp(UnsignedLessThan);
1035         Le (_) icmp(UnsignedLessThanOrEqual);
1036         Ne (_) icmp(NotEqual);
1037         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1038         Gt (_) icmp(UnsignedGreaterThan);
1039
1040         Offset (_) bug;
1041     };
1042
1043     res
1044 }
1045
1046 fn trans_ptr_binop<'a, 'tcx: 'a>(
1047     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1048     bin_op: BinOp,
1049     lhs: CValue<'tcx>,
1050     rhs: CValue<'tcx>,
1051     ret_ty: Ty<'tcx>,
1052 ) -> CValue<'tcx> {
1053     let not_fat = match lhs.layout().ty.sty {
1054         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1055             ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
1056         }
1057         ty::FnPtr(..) => true,
1058         _ => bug!("trans_ptr_binop on non ptr"),
1059     };
1060     if not_fat {
1061         if let BinOp::Offset = bin_op {
1062             let (base, offset) = (lhs, rhs.load_scalar(fx));
1063             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
1064             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
1065             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
1066             let base_val = base.load_scalar(fx);
1067             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
1068             return CValue::by_val(res, base.layout());
1069         }
1070
1071         binop_match! {
1072             fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1073             Add (_) bug;
1074             Sub (_) bug;
1075             Mul (_) bug;
1076             Div (_) bug;
1077             Rem (_) bug;
1078             BitXor (_) bug;
1079             BitAnd (_) bug;
1080             BitOr (_) bug;
1081             Shl (_) bug;
1082             Shr (_) bug;
1083
1084             Eq (_) icmp(Equal);
1085             Lt (_) icmp(UnsignedLessThan);
1086             Le (_) icmp(UnsignedLessThanOrEqual);
1087             Ne (_) icmp(NotEqual);
1088             Ge (_) icmp(UnsignedGreaterThanOrEqual);
1089             Gt (_) icmp(UnsignedGreaterThan);
1090
1091             Offset (_) bug; // Handled above
1092         }
1093     } else {
1094         let (lhs_ptr, lhs_extra) = lhs.load_scalar_pair(fx);
1095         let (rhs_ptr, rhs_extra) = rhs.load_scalar_pair(fx);
1096
1097         let res = match bin_op {
1098             BinOp::Eq => {
1099                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1100                 let extra_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_extra, rhs_extra);
1101                 fx.bcx.ins().band(ptr_eq, extra_eq)
1102             }
1103             BinOp::Ne => {
1104                 let ptr_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_ptr, rhs_ptr);
1105                 let extra_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_extra, rhs_extra);
1106                 fx.bcx.ins().bor(ptr_ne, extra_ne)
1107             }
1108             BinOp::Lt | BinOp::Le | BinOp::Ge | BinOp::Gt => {
1109                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1110
1111                 let ptr_cmp = fx.bcx.ins().icmp(match bin_op {
1112                     BinOp::Lt => IntCC::UnsignedLessThan,
1113                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1114                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1115                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1116                     _ => unreachable!(),
1117                 }, lhs_ptr, rhs_ptr);
1118
1119                 let extra_cmp = fx.bcx.ins().icmp(match bin_op {
1120                     BinOp::Lt => IntCC::UnsignedLessThan,
1121                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1122                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1123                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1124                     _ => unreachable!(),
1125                 }, lhs_extra, rhs_extra);
1126
1127                 fx.bcx.ins().select(ptr_eq, extra_cmp, ptr_cmp)
1128             }
1129             _ => panic!("bin_op {:?} on ptr", bin_op),
1130         };
1131
1132         assert_eq!(fx.tcx.types.bool, ret_ty);
1133         let ret_layout = fx.layout_of(ret_ty);
1134         CValue::by_val(fx.bcx.ins().bint(types::I8, res), ret_layout)
1135     }
1136 }
1137
1138 pub fn trans_place<'a, 'tcx: 'a>(
1139     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1140     place: &Place<'tcx>,
1141 ) -> CPlace<'tcx> {
1142     let base = match &place.base {
1143         PlaceBase::Local(local) => fx.get_local_place(*local),
1144         PlaceBase::Static(static_) => match static_.kind {
1145             StaticKind::Static(def_id) => {
1146                 crate::constant::codegen_static_ref(fx, def_id, static_.ty)
1147             }
1148             StaticKind::Promoted(promoted) => {
1149                 crate::constant::trans_promoted(fx, promoted, static_.ty)
1150             }
1151         }
1152     };
1153
1154     trans_place_projection(fx, base, &place.projection)
1155 }
1156
1157 pub fn trans_place_projection<'a, 'tcx: 'a>(
1158     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1159     base: CPlace<'tcx>,
1160     projection: &Option<Box<Projection<'tcx>>>,
1161 ) -> CPlace<'tcx> {
1162     let projection = if let Some(projection) = projection {
1163         projection
1164     } else {
1165         return base;
1166     };
1167
1168     let base = trans_place_projection(fx, base, &projection.base);
1169
1170     match projection.elem {
1171         ProjectionElem::Deref => base.place_deref(fx),
1172         ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1173         ProjectionElem::Index(local) => {
1174             let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1175             base.place_index(fx, index)
1176         }
1177         ProjectionElem::ConstantIndex {
1178             offset,
1179             min_length: _,
1180             from_end,
1181         } => {
1182             let index = if !from_end {
1183                 fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1184             } else {
1185                 let len = codegen_array_len(fx, base);
1186                 fx.bcx.ins().iadd_imm(len, -(offset as i64))
1187             };
1188             base.place_index(fx, index)
1189         }
1190         ProjectionElem::Subslice { from, to } => {
1191             // These indices are generated by slice patterns.
1192             // slice[from:-to] in Python terms.
1193
1194             match base.layout().ty.sty {
1195                 ty::Array(elem_ty, len) => {
1196                     let elem_layout = fx.layout_of(elem_ty);
1197                     let ptr = base.to_addr(fx);
1198                     let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx);
1199                     CPlace::for_addr(
1200                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1201                         fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
1202                     )
1203                 }
1204                 ty::Slice(elem_ty) => {
1205                     let elem_layout = fx.layout_of(elem_ty);
1206                     let (ptr, len) = base.to_addr_maybe_unsized(fx);
1207                     let len = len.unwrap();
1208                     CPlace::for_addr_with_extra(
1209                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1210                         fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
1211                         base.layout(),
1212                     )
1213                 }
1214                 _ => unreachable!(),
1215             }
1216         }
1217         ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1218     }
1219 }
1220
1221 pub fn trans_operand<'a, 'tcx>(
1222     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1223     operand: &Operand<'tcx>,
1224 ) -> CValue<'tcx> {
1225     match operand {
1226         Operand::Move(place) | Operand::Copy(place) => {
1227             let cplace = trans_place(fx, place);
1228             cplace.to_cvalue(fx)
1229         }
1230         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1231     }
1232 }