src/base.rs

   1 use crate::prelude::*;
   2
   3 struct PrintOnPanic<F: Fn() -> String>(F);
   4 impl<F: Fn() -> String> Drop for PrintOnPanic<F> {
   5     fn drop(&mut self) {
   6         if ::std::thread::panicking() {
   7             println!("{}", (self.0)());
   8         }
   9     }
  10 }
  11
  12 pub fn trans_mono_item<'a, 'clif, 'tcx: 'a, B: Backend + 'static>(
  13     cx: &mut crate::CodegenCx<'a, 'clif, 'tcx, B>,
  14     mono_item: MonoItem<'tcx>,
  15     linkage: Linkage,
  16 ) {
  17     let tcx = cx.tcx;
  18     match mono_item {
  19         MonoItem::Fn(inst) => {
  20             let _inst_guard =
  21                 PrintOnPanic(|| format!("{:?} {}", inst, tcx.symbol_name(inst).as_str()));
  22             debug_assert!(!inst.substs.needs_infer());
  23             let _mir_guard = PrintOnPanic(|| {
  24                 match inst.def {
  25                     InstanceDef::Item(_)
  26                     | InstanceDef::DropGlue(_, _)
  27                     | InstanceDef::Virtual(_, _)
  28                         if inst.def_id().krate == LOCAL_CRATE =>
  29                     {
  30                         let mut mir = ::std::io::Cursor::new(Vec::new());
  31                         crate::rustc_mir::util::write_mir_pretty(
  32                             tcx,
  33                             Some(inst.def_id()),
  34                             &mut mir,
  35                         )
  36                         .unwrap();
  37                         String::from_utf8(mir.into_inner()).unwrap()
  38                     }
  39                     _ => {
  40                         // FIXME fix write_mir_pretty for these instances
  41                         format!("{:#?}", tcx.instance_mir(inst.def))
  42                     }
  43                 }
  44             });
  45
  46             trans_fn(cx, inst, linkage);
  47         }
  48         MonoItem::Static(def_id) => {
  49             crate::constant::codegen_static(&mut cx.ccx, def_id);
  50         }
  51         MonoItem::GlobalAsm(node_id) => tcx
  52             .sess
  53             .fatal(&format!("Unimplemented global asm mono item {:?}", node_id)),
  54     }
  55 }
  56
  57 fn trans_fn<'a, 'clif, 'tcx: 'a, B: Backend + 'static>(
  58     cx: &mut crate::CodegenCx<'a, 'clif, 'tcx, B>,
  59     instance: Instance<'tcx>,
  60     linkage: Linkage,
  61 ) {
  62     let tcx = cx.tcx;
  63
  64     // Step 1. Get mir
  65     let mir = tcx.instance_mir(instance.def);
  66
  67     // Step 2. Check fn sig for u128 and i128 and replace those functions with a trap.
  68     {
  69         // FIXME implement u128 and i128 support
  70
  71         // Step 2a. Check sig for u128 and i128
  72         let fn_sig = tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), &instance.fn_sig(tcx));
  73
  74         struct UI128Visitor<'a, 'tcx: 'a>(TyCtxt<'a, 'tcx, 'tcx>, bool);
  75
  76         impl<'a, 'tcx: 'a> rustc::ty::fold::TypeVisitor<'tcx> for UI128Visitor<'a, 'tcx> {
  77             fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
  78                 if t.sty == self.0.types.u128.sty || t.sty == self.0.types.i128.sty {
  79                     self.1 = true;
  80                     return false; // stop visiting
  81                 }
  82
  83                 t.super_visit_with(self)
  84             }
  85         }
  86
  87         let mut visitor = UI128Visitor(tcx, false);
  88         fn_sig.visit_with(&mut visitor);
  89
  90         // Step 2b. If found replace function with a trap.
  91         if visitor.1 {
  92             tcx.sess.warn("u128 and i128 are not yet supported. \
  93             Functions using these as args will be replaced with a trap.");
  94
  95             // Step 2b1. Declare function with fake signature
  96             let sig = Signature {
  97                 params: vec![AbiParam::new(types::INVALID)],
  98                 returns: vec![],
  99                 call_conv: CallConv::Fast,
 100             };
 101             let name = tcx.symbol_name(instance).as_str();
 102             let func_id = cx.module.declare_function(&*name, linkage, &sig).unwrap();
 103
 104             // Step 2b2. Create trapping function
 105             let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
 106             let mut func_ctx = FunctionBuilderContext::new();
 107             let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
 108             let start_ebb = bcx.create_ebb();
 109             bcx.append_ebb_params_for_function_params(start_ebb);
 110             bcx.switch_to_block(start_ebb);
 111
 112             let mut fx = FunctionCx {
 113                 tcx,
 114                 module: cx.module,
 115                 pointer_type: pointer_ty(tcx),
 116
 117                 instance,
 118                 mir,
 119
 120                 bcx,
 121                 ebb_map: HashMap::new(),
 122                 local_map: HashMap::new(),
 123
 124                 clif_comments: crate::pretty_clif::CommentWriter::new(tcx, instance),
 125                 constants: &mut cx.ccx,
 126                 caches: &mut cx.caches,
 127                 source_info_set: indexmap::IndexSet::new(),
 128             };
 129
 130             crate::trap::trap_unreachable(&mut fx, "[unimplemented] Called function with u128 or i128 as argument.");
 131             fx.bcx.seal_all_blocks();
 132             fx.bcx.finalize();
 133
 134             // Step 2b3. Define function
 135             cx.caches.context.func = func;
 136             cx.module
 137                 .define_function(func_id, &mut cx.caches.context)
 138                 .unwrap();
 139             cx.caches.context.clear();
 140             return;
 141         }
 142     }
 143
 144     // Step 3. Declare function
 145     let (name, sig) = get_function_name_and_sig(tcx, instance, false);
 146     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
 147     let mut debug_context = cx
 148         .debug_context
 149         .as_mut()
 150         .map(|debug_context| FunctionDebugContext::new(tcx, debug_context, mir, &name, &sig));
 151
 152     // Step 4. Make FunctionBuilder
 153     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
 154     let mut func_ctx = FunctionBuilderContext::new();
 155     let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
 156
 157     // Step 5. Predefine ebb's
 158     let start_ebb = bcx.create_ebb();
 159     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
 160     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
 161         ebb_map.insert(bb, bcx.create_ebb());
 162     }
 163
 164     // Step 6. Make FunctionCx
 165     let pointer_type = cx.module.target_config().pointer_type();
 166     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
 167
 168     let mut fx = FunctionCx {
 169         tcx,
 170         module: cx.module,
 171         pointer_type,
 172
 173         instance,
 174         mir,
 175
 176         bcx,
 177         ebb_map,
 178         local_map: HashMap::new(),
 179
 180         clif_comments,
 181         constants: &mut cx.ccx,
 182         caches: &mut cx.caches,
 183         source_info_set: indexmap::IndexSet::new(),
 184     };
 185
 186     // Step 7. Codegen function
 187     with_unimpl_span(fx.mir.span, || {
 188         crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
 189         codegen_fn_content(&mut fx);
 190     });
 191     let source_info_set = fx.source_info_set.clone();
 192
 193     // Step 8. Write function to file for debugging
 194     #[cfg(debug_assertions)]
 195     fx.write_clif_file();
 196
 197     // Step 9. Verify function
 198     verify_func(tcx, fx.clif_comments, &func);
 199
 200     // Step 10. Define function
 201     cx.caches.context.func = func;
 202     cx.module
 203         .define_function(func_id, &mut cx.caches.context)
 204         .unwrap();
 205
 206     // Step 11. Define debuginfo for function
 207     let context = &cx.caches.context;
 208     let isa = cx.module.isa();
 209     debug_context
 210         .as_mut()
 211         .map(|x| x.define(tcx, context, isa, &source_info_set));
 212
 213     // Step 12. Clear context to make it usable for the next function
 214     cx.caches.context.clear();
 215 }
 216
 217 fn verify_func(tcx: TyCtxt, writer: crate::pretty_clif::CommentWriter, func: &Function) {
 218     let flags = settings::Flags::new(settings::builder());
 219     match ::cranelift::codegen::verify_function(&func, &flags) {
 220         Ok(_) => {}
 221         Err(err) => {
 222             tcx.sess.err(&format!("{:?}", err));
 223             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 224                 &func,
 225                 None,
 226                 Some(Box::new(&writer)),
 227                 err,
 228             );
 229             tcx.sess
 230                 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
 231         }
 232     }
 233 }
 234
 235 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 236     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 237         if bb_data.is_cleanup {
 238             // Unwinding after panicking is not supported
 239             continue;
 240         }
 241
 242         let ebb = fx.get_ebb(bb);
 243         fx.bcx.switch_to_block(ebb);
 244
 245         fx.bcx.ins().nop();
 246         for stmt in &bb_data.statements {
 247             fx.set_debug_loc(stmt.source_info);
 248             trans_stmt(fx, ebb, stmt);
 249         }
 250
 251         #[cfg(debug_assertions)]
 252         {
 253             let mut terminator_head = "\n".to_string();
 254             bb_data
 255                 .terminator()
 256                 .kind
 257                 .fmt_head(&mut terminator_head)
 258                 .unwrap();
 259             let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 260             fx.add_comment(inst, terminator_head);
 261         }
 262
 263         fx.set_debug_loc(bb_data.terminator().source_info);
 264
 265         match &bb_data.terminator().kind {
 266             TerminatorKind::Goto { target } => {
 267                 let ebb = fx.get_ebb(*target);
 268                 fx.bcx.ins().jump(ebb, &[]);
 269             }
 270             TerminatorKind::Return => {
 271                 crate::abi::codegen_return(fx);
 272             }
 273             TerminatorKind::Assert {
 274                 cond,
 275                 expected,
 276                 msg,
 277                 target,
 278                 cleanup: _,
 279             } => {
 280                 let cond = trans_operand(fx, cond).load_scalar(fx);
 281                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 282                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 283                 let target = fx.get_ebb(*target);
 284                 if *expected {
 285                     fx.bcx.ins().brnz(cond, target, &[]);
 286                 } else {
 287                     fx.bcx.ins().brz(cond, target, &[]);
 288                 };
 289                 trap_panic(fx, format!("[panic] Assert {:?} failed.", msg));
 290             }
 291
 292             TerminatorKind::SwitchInt {
 293                 discr,
 294                 switch_ty: _,
 295                 values,
 296                 targets,
 297             } => {
 298                 let discr = trans_operand(fx, discr).load_scalar(fx);
 299                 let mut switch = ::cranelift::frontend::Switch::new();
 300                 for (i, value) in values.iter().enumerate() {
 301                     let ebb = fx.get_ebb(targets[i]);
 302                     switch.set_entry(*value as u64, ebb);
 303                 }
 304                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 305                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 306             }
 307             TerminatorKind::Call {
 308                 func,
 309                 args,
 310                 destination,
 311                 cleanup: _,
 312                 from_hir_call: _,
 313             } => {
 314                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 315             }
 316             TerminatorKind::Resume | TerminatorKind::Abort => {
 317                 trap_unreachable(fx, "[corruption] Unwinding bb reached.");
 318             }
 319             TerminatorKind::Unreachable => {
 320                 trap_unreachable(fx, "[corruption] Hit unreachable code.");
 321             }
 322             TerminatorKind::Yield { .. }
 323             | TerminatorKind::FalseEdges { .. }
 324             | TerminatorKind::FalseUnwind { .. }
 325             | TerminatorKind::DropAndReplace { .. }
 326             | TerminatorKind::GeneratorDrop => {
 327                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 328             }
 329             TerminatorKind::Drop {
 330                 location,
 331                 target,
 332                 unwind: _,
 333             } => {
 334                 let ty = location.ty(fx.mir, fx.tcx).ty;
 335                 let ty = fx.monomorphize(&ty);
 336                 let drop_fn = crate::rustc_mir::monomorphize::resolve_drop_in_place(fx.tcx, ty);
 337
 338                 if let ty::InstanceDef::DropGlue(_, None) = drop_fn.def {
 339                     // we don't actually need to drop anything
 340                 } else {
 341                     let drop_place = trans_place(fx, location);
 342                     let drop_fn_ty = drop_fn.ty(fx.tcx);
 343                     match ty.sty {
 344                         ty::Dynamic(..) => {
 345                             crate::abi::codegen_drop(fx, drop_place, drop_fn_ty);
 346                         }
 347                         _ => {
 348                             let arg_place = CPlace::new_stack_slot(
 349                                 fx,
 350                                 fx.tcx.mk_ref(
 351                                     &ty::RegionKind::ReErased,
 352                                     TypeAndMut {
 353                                         ty,
 354                                         mutbl: crate::rustc::hir::Mutability::MutMutable,
 355                                     },
 356                                 ),
 357                             );
 358                             drop_place.write_place_ref(fx, arg_place);
 359                             let arg_value = arg_place.to_cvalue(fx);
 360                             crate::abi::codegen_call_inner(
 361                                 fx,
 362                                 None,
 363                                 drop_fn_ty,
 364                                 vec![arg_value],
 365                                 None,
 366                             );
 367                         }
 368                     }
 369                 }
 370
 371                 let target_ebb = fx.get_ebb(*target);
 372                 fx.bcx.ins().jump(target_ebb, &[]);
 373             }
 374         };
 375     }
 376
 377     fx.bcx.seal_all_blocks();
 378     fx.bcx.finalize();
 379 }
 380
 381 fn trans_stmt<'a, 'tcx: 'a>(
 382     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 383     cur_ebb: Ebb,
 384     stmt: &Statement<'tcx>,
 385 ) {
 386     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 387
 388     fx.set_debug_loc(stmt.source_info);
 389
 390     #[cfg(debug_assertions)]
 391     match &stmt.kind {
 392         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 393         _ => {
 394             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 395             fx.add_comment(inst, format!("{:?}", stmt));
 396         }
 397     }
 398
 399     match &stmt.kind {
 400         StatementKind::SetDiscriminant {
 401             place,
 402             variant_index,
 403         } => {
 404             let place = trans_place(fx, place);
 405             let layout = place.layout();
 406             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 407                 return;
 408             }
 409             match layout.variants {
 410                 layout::Variants::Single { index } => {
 411                     assert_eq!(index, *variant_index);
 412                 }
 413                 layout::Variants::Multiple {
 414                     discr: _,
 415                     discr_index,
 416                     discr_kind: layout::DiscriminantKind::Tag,
 417                     variants: _,
 418                 } => {
 419                     let ptr = place.place_field(fx, mir::Field::new(discr_index));
 420                     let to = layout
 421                         .ty
 422                         .ty_adt_def()
 423                         .unwrap()
 424                         .discriminant_for_variant(fx.tcx, *variant_index)
 425                         .val;
 426                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 427                     ptr.write_cvalue(fx, discr);
 428                 }
 429                 layout::Variants::Multiple {
 430                     discr: _,
 431                     discr_index,
 432                     discr_kind: layout::DiscriminantKind::Niche {
 433                         dataful_variant,
 434                         ref niche_variants,
 435                         niche_start,
 436                     },
 437                     variants: _,
 438                 } => {
 439                     if *variant_index != dataful_variant {
 440                         let niche = place.place_field(fx, mir::Field::new(discr_index));
 441                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 442                         let niche_value =
 443                             ((variant_index.as_u32() - niche_variants.start().as_u32()) as u128)
 444                                 .wrapping_add(niche_start);
 445                         // FIXME(eddyb) Check the actual primitive type here.
 446                         let niche_llval = if niche_value == 0 {
 447                             CValue::const_val(fx, niche.layout().ty, 0)
 448                         } else {
 449                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 450                         };
 451                         niche.write_cvalue(fx, niche_llval);
 452                     }
 453                 }
 454             }
 455         }
 456         StatementKind::Assign(to_place, rval) => {
 457             let lval = trans_place(fx, to_place);
 458             let dest_layout = lval.layout();
 459             match &**rval {
 460                 Rvalue::Use(operand) => {
 461                     let val = trans_operand(fx, operand);
 462                     lval.write_cvalue(fx, val);
 463                 }
 464                 Rvalue::Ref(_, _, place) => {
 465                     let place = trans_place(fx, place);
 466                     place.write_place_ref(fx, lval);
 467                 }
 468                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 469                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 470                     let lhs = trans_operand(fx, lhs);
 471                     let rhs = trans_operand(fx, rhs);
 472
 473                     let res = match ty.sty {
 474                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 475                         ty::Uint(_) => {
 476                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 477                         }
 478                         ty::Int(_) => {
 479                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 480                         }
 481                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 482                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 483                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 484                         ty::FnPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 485                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 486                     };
 487                     lval.write_cvalue(fx, res);
 488                 }
 489                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 490                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 491                     let lhs = trans_operand(fx, lhs);
 492                     let rhs = trans_operand(fx, rhs);
 493
 494                     let res = match ty.sty {
 495                         ty::Uint(_) => {
 496                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 497                         }
 498                         ty::Int(_) => {
 499                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 500                         }
 501                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 502                     };
 503                     lval.write_cvalue(fx, res);
 504                 }
 505                 Rvalue::UnaryOp(un_op, operand) => {
 506                     let operand = trans_operand(fx, operand);
 507                     let layout = operand.layout();
 508                     let val = operand.load_scalar(fx);
 509                     let res = match un_op {
 510                         UnOp::Not => {
 511                             match layout.ty.sty {
 512                                 ty::Bool => {
 513                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 514                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 515                                     fx.bcx.ins().bint(types::I8, res)
 516                                 }
 517                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 518                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 519                             }
 520                         }
 521                         UnOp::Neg => match layout.ty.sty {
 522                             ty::Int(_) => {
 523                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 524                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 525                                 fx.bcx.ins().isub(zero, val)
 526                             }
 527                             ty::Float(_) => fx.bcx.ins().fneg(val),
 528                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 529                         },
 530                     };
 531                     lval.write_cvalue(fx, CValue::ByVal(res, layout));
 532                 }
 533                 Rvalue::Cast(CastKind::ReifyFnPointer, operand, ty) => {
 534                     let layout = fx.layout_of(ty);
 535                     match fx
 536                         .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
 537                         .sty
 538                     {
 539                         ty::FnDef(def_id, substs) => {
 540                             let func_ref = fx.get_function_ref(
 541                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
 542                                     .unwrap(),
 543                             );
 544                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 545                             lval.write_cvalue(fx, CValue::ByVal(func_addr, layout));
 546                         }
 547                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 548                     }
 549                 }
 550                 Rvalue::Cast(CastKind::UnsafeFnPointer, operand, ty)
 551                 | Rvalue::Cast(CastKind::MutToConstPointer, operand, ty) => {
 552                     let operand = trans_operand(fx, operand);
 553                     let layout = fx.layout_of(ty);
 554                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 555                 }
 556                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 557                     let operand = trans_operand(fx, operand);
 558                     let from_ty = operand.layout().ty;
 559
 560                     fn is_fat_ptr<'a, 'tcx: 'a>(fx: &FunctionCx<'a, 'tcx, impl Backend>, ty: Ty<'tcx>) -> bool {
 561                         ty
 562                             .builtin_deref(true)
 563                             .map(|ty::TypeAndMut {ty: pointee_ty, mutbl: _ }| fx.layout_of(pointee_ty).is_unsized())
 564                             .unwrap_or(false)
 565                     }
 566
 567                     if is_fat_ptr(fx, from_ty) {
 568                         if is_fat_ptr(fx, to_ty) {
 569                             // fat-ptr -> fat-ptr
 570                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 571                         } else {
 572                             // fat-ptr -> thin-ptr
 573                             let (ptr, _extra) = operand.load_scalar_pair(fx);
 574                             lval.write_cvalue(fx, CValue::ByVal(ptr, dest_layout))
 575                         }
 576                     } else if let ty::Adt(adt_def, _substs) = from_ty.sty {
 577                         // enum -> discriminant value
 578                         assert!(adt_def.is_enum());
 579                         match to_ty.sty {
 580                             ty::Uint(_) | ty::Int(_) => {},
 581                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
 582                         }
 583
 584                         // FIXME avoid forcing to stack
 585                         let place =
 586                             CPlace::Addr(operand.force_stack(fx), None, operand.layout());
 587                         let discr = trans_get_discriminant(fx, place, fx.layout_of(to_ty));
 588                         lval.write_cvalue(fx, discr);
 589                     } else {
 590                         let from_clif_ty = fx.clif_type(from_ty).unwrap();
 591                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
 592                         let from = operand.load_scalar(fx);
 593
 594                         let signed = match from_ty.sty {
 595                             ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 596                             ty::Int(..) => true,
 597                             ty::Float(..) => false, // `signed` is unused for floats
 598                             _ => panic!("{}", from_ty),
 599                         };
 600
 601                         let res = if from_clif_ty.is_int() && to_clif_ty.is_int() {
 602                             // int-like -> int-like
 603                             crate::common::clif_intcast(
 604                                 fx,
 605                                 from,
 606                                 to_clif_ty,
 607                                 signed,
 608                             )
 609                         } else if from_clif_ty.is_int() && to_clif_ty.is_float() {
 610                             // int-like -> float
 611                             // FIXME missing encoding for fcvt_from_sint.f32.i8
 612                             let from = if from_clif_ty == types::I8 || from_clif_ty == types::I16 {
 613                                 fx.bcx.ins().uextend(types::I32, from)
 614                             } else {
 615                                 from
 616                             };
 617                             if signed {
 618                                 fx.bcx.ins().fcvt_from_sint(to_clif_ty, from)
 619                             } else {
 620                                 fx.bcx.ins().fcvt_from_uint(to_clif_ty, from)
 621                             }
 622                         } else if from_clif_ty.is_float() && to_clif_ty.is_int() {
 623                             // float -> int-like
 624                             let from = operand.load_scalar(fx);
 625                             if signed {
 626                                 fx.bcx.ins().fcvt_to_sint_sat(to_clif_ty, from)
 627                             } else {
 628                                 fx.bcx.ins().fcvt_to_uint_sat(to_clif_ty, from)
 629                             }
 630                         } else if from_clif_ty.is_float() && to_clif_ty.is_float() {
 631                             // float -> float
 632                             match (from_clif_ty, to_clif_ty) {
 633                                 (types::F32, types::F64) => {
 634                                     fx.bcx.ins().fpromote(types::F64, from)
 635                                 }
 636                                 (types::F64, types::F32) => {
 637                                     fx.bcx.ins().fdemote(types::F32, from)
 638                                 }
 639                                 _ => from,
 640                             }
 641                         } else {
 642                             unimpl!("rval misc {:?} {:?}", from_ty, to_ty)
 643                         };
 644                         lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 645                     }
 646                 }
 647                 Rvalue::Cast(CastKind::ClosureFnPointer(_), operand, _ty) => {
 648                     let operand = trans_operand(fx, operand);
 649                     match operand.layout().ty.sty {
 650                         ty::Closure(def_id, substs) => {
 651                             let instance = rustc_mir::monomorphize::resolve_closure(
 652                                 fx.tcx,
 653                                 def_id,
 654                                 substs,
 655                                 ty::ClosureKind::FnOnce,
 656                             );
 657                             let func_ref = fx.get_function_ref(instance);
 658                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 659                             lval.write_cvalue(fx, CValue::ByVal(func_addr, lval.layout()));
 660                         }
 661                         _ => {
 662                             bug!("{} cannot be cast to a fn ptr", operand.layout().ty)
 663                         }
 664                     }
 665                 }
 666                 Rvalue::Cast(CastKind::Unsize, operand, _ty) => {
 667                     let operand = trans_operand(fx, operand);
 668                     operand.unsize_value(fx, lval);
 669                 }
 670                 Rvalue::Discriminant(place) => {
 671                     let place = trans_place(fx, place);
 672                     let discr = trans_get_discriminant(fx, place, dest_layout);
 673                     lval.write_cvalue(fx, discr);
 674                 }
 675                 Rvalue::Repeat(operand, times) => {
 676                     let operand = trans_operand(fx, operand);
 677                     for i in 0..*times {
 678                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 679                         let to = lval.place_index(fx, index);
 680                         to.write_cvalue(fx, operand);
 681                     }
 682                 }
 683                 Rvalue::Len(place) => {
 684                     let place = trans_place(fx, place);
 685                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 686                     let len = codegen_array_len(fx, place);
 687                     lval.write_cvalue(fx, CValue::ByVal(len, usize_layout));
 688                 }
 689                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 690                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 691
 692                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 693                     let layout = fx.layout_of(content_ty);
 694                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 695                     let llalign = fx
 696                         .bcx
 697                         .ins()
 698                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 699                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 700
 701                     // Allocate space:
 702                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 703                         Ok(id) => id,
 704                         Err(s) => {
 705                             fx.tcx
 706                                 .sess
 707                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 708                         }
 709                     };
 710                     let instance = ty::Instance::mono(fx.tcx, def_id);
 711                     let func_ref = fx.get_function_ref(instance);
 712                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 713                     let ptr = fx.bcx.inst_results(call)[0];
 714                     lval.write_cvalue(fx, CValue::ByVal(ptr, box_layout));
 715                 }
 716                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 717                     assert!(lval
 718                         .layout()
 719                         .ty
 720                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 721                     let ty_size = fx.layout_of(ty).size.bytes();
 722                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 723                     lval.write_cvalue(fx, val);
 724                 }
 725                 Rvalue::Aggregate(kind, operands) => match **kind {
 726                     AggregateKind::Array(_ty) => {
 727                         for (i, operand) in operands.into_iter().enumerate() {
 728                             let operand = trans_operand(fx, operand);
 729                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 730                             let to = lval.place_index(fx, index);
 731                             to.write_cvalue(fx, operand);
 732                         }
 733                     }
 734                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 735                 },
 736             }
 737         }
 738         StatementKind::StorageLive(_)
 739         | StatementKind::StorageDead(_)
 740         | StatementKind::Nop
 741         | StatementKind::FakeRead(..)
 742         | StatementKind::Retag { .. }
 743         | StatementKind::AscribeUserType(..) => {}
 744
 745         StatementKind::InlineAsm { .. } => unimpl!("Inline assembly is not supported"),
 746     }
 747 }
 748
 749 fn codegen_array_len<'a, 'tcx: 'a>(
 750     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 751     place: CPlace<'tcx>,
 752 ) -> Value {
 753     match place.layout().ty.sty {
 754         ty::Array(_elem_ty, len) => {
 755             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx) as i64;
 756             fx.bcx.ins().iconst(fx.pointer_type, len)
 757         }
 758         ty::Slice(_elem_ty) => place
 759             .to_addr_maybe_unsized(fx)
 760             .1
 761             .expect("Length metadata for slice place"),
 762         _ => bug!("Rvalue::Len({:?})", place),
 763     }
 764 }
 765
 766 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 767     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 768     place: CPlace<'tcx>,
 769     dest_layout: TyLayout<'tcx>,
 770 ) -> CValue<'tcx> {
 771     let layout = place.layout();
 772
 773     if layout.abi == layout::Abi::Uninhabited {
 774         return trap_unreachable_ret_value(fx, dest_layout, "[panic] Tried to get discriminant for uninhabited type.");
 775     }
 776
 777     let (discr_scalar, discr_index, discr_kind) = match &layout.variants {
 778         layout::Variants::Single { index } => {
 779             let discr_val = layout
 780                 .ty
 781                 .ty_adt_def()
 782                 .map_or(index.as_u32() as u128, |def| {
 783                     def.discriminant_for_variant(fx.tcx, *index).val
 784                 });
 785             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 786         }
 787         layout::Variants::Multiple { discr, discr_index, discr_kind, variants: _ } => {
 788             (discr, *discr_index, discr_kind)
 789         }
 790     };
 791
 792     let discr = place.place_field(fx, mir::Field::new(discr_index)).to_cvalue(fx);
 793     let discr_ty = discr.layout().ty;
 794     let lldiscr = discr.load_scalar(fx);
 795     match discr_kind {
 796         layout::DiscriminantKind::Tag => {
 797             let signed = match discr_scalar.value {
 798                 layout::Int(_, signed) => signed,
 799                 _ => false,
 800             };
 801             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 802             return CValue::ByVal(val, dest_layout);
 803         }
 804         layout::DiscriminantKind::Niche {
 805             dataful_variant,
 806             ref niche_variants,
 807             niche_start,
 808         } => {
 809             let niche_llty = fx.clif_type(discr_ty).unwrap();
 810             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 811             if niche_variants.start() == niche_variants.end() {
 812                 let b = fx
 813                     .bcx
 814                     .ins()
 815                     .icmp_imm(IntCC::Equal, lldiscr, *niche_start as u64 as i64);
 816                 let if_true = fx
 817                     .bcx
 818                     .ins()
 819                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 820                 let if_false = fx
 821                     .bcx
 822                     .ins()
 823                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 824                 let val = fx.bcx.ins().select(b, if_true, if_false);
 825                 return CValue::ByVal(val, dest_layout);
 826             } else {
 827                 // Rebase from niche values to discriminant values.
 828                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 829                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 830                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 831                 let b = fx.bcx.ins().icmp_imm(
 832                     IntCC::UnsignedLessThanOrEqual,
 833                     lldiscr,
 834                     niche_variants.end().as_u32() as i64,
 835                 );
 836                 let if_true =
 837                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 838                 let if_false = fx
 839                     .bcx
 840                     .ins()
 841                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 842                 let val = fx.bcx.ins().select(b, if_true, if_false);
 843                 return CValue::ByVal(val, dest_layout);
 844             }
 845         }
 846     }
 847 }
 848
 849 macro_rules! binop_match {
 850     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 851         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 852     };
 853     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 854         assert_eq!($fx.tcx.types.bool, $ret_ty);
 855         let ret_layout = $fx.layout_of($ret_ty);
 856
 857         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 858         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 859     }};
 860     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 861         assert_eq!($fx.tcx.types.bool, $ret_ty);
 862         let ret_layout = $fx.layout_of($ret_ty);
 863         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 864         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 865     }};
 866     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 867         $body
 868     }};
 869     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 870         let ret_layout = $fx.layout_of($ret_ty);
 871         CValue::ByVal($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 872     }};
 873     (
 874         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 875         $(
 876             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 877         )*
 878     ) => {{
 879         let lhs = $lhs.load_scalar($fx);
 880         let rhs = $rhs.load_scalar($fx);
 881         match ($bin_op, $signed) {
 882             $(
 883                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 884             )*
 885         }
 886     }}
 887 }
 888
 889 fn trans_bool_binop<'a, 'tcx: 'a>(
 890     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 891     bin_op: BinOp,
 892     lhs: CValue<'tcx>,
 893     rhs: CValue<'tcx>,
 894     ty: Ty<'tcx>,
 895 ) -> CValue<'tcx> {
 896     let res = binop_match! {
 897         fx, bin_op, false, lhs, rhs, ty, "bool";
 898         Add (_) bug;
 899         Sub (_) bug;
 900         Mul (_) bug;
 901         Div (_) bug;
 902         Rem (_) bug;
 903         BitXor (_) bxor;
 904         BitAnd (_) band;
 905         BitOr (_) bor;
 906         Shl (_) bug;
 907         Shr (_) bug;
 908
 909         Eq (_) icmp(Equal);
 910         Lt (_) icmp(UnsignedLessThan);
 911         Le (_) icmp(UnsignedLessThanOrEqual);
 912         Ne (_) icmp(NotEqual);
 913         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 914         Gt (_) icmp(UnsignedGreaterThan);
 915
 916         Offset (_) bug;
 917     };
 918
 919     res
 920 }
 921
 922 pub fn trans_int_binop<'a, 'tcx: 'a>(
 923     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 924     bin_op: BinOp,
 925     lhs: CValue<'tcx>,
 926     rhs: CValue<'tcx>,
 927     out_ty: Ty<'tcx>,
 928     signed: bool,
 929 ) -> CValue<'tcx> {
 930     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 931         assert_eq!(
 932             lhs.layout().ty,
 933             rhs.layout().ty,
 934             "int binop requires lhs and rhs of same type"
 935         );
 936     }
 937     binop_match! {
 938         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 939         Add (_) iadd;
 940         Sub (_) isub;
 941         Mul (_) imul;
 942         Div (false) udiv;
 943         Div (true) sdiv;
 944         Rem (false) urem;
 945         Rem (true) srem;
 946         BitXor (_) bxor;
 947         BitAnd (_) band;
 948         BitOr (_) bor;
 949         Shl (_) ishl;
 950         Shr (false) ushr;
 951         Shr (true) sshr;
 952
 953         Eq (_) icmp(Equal);
 954         Lt (false) icmp(UnsignedLessThan);
 955         Lt (true) icmp(SignedLessThan);
 956         Le (false) icmp(UnsignedLessThanOrEqual);
 957         Le (true) icmp(SignedLessThanOrEqual);
 958         Ne (_) icmp(NotEqual);
 959         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 960         Ge (true) icmp(SignedGreaterThanOrEqual);
 961         Gt (false) icmp(UnsignedGreaterThan);
 962         Gt (true) icmp(SignedGreaterThan);
 963
 964         Offset (_) bug;
 965     }
 966 }
 967
 968 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 969     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 970     bin_op: BinOp,
 971     in_lhs: CValue<'tcx>,
 972     in_rhs: CValue<'tcx>,
 973     out_ty: Ty<'tcx>,
 974     signed: bool,
 975 ) -> CValue<'tcx> {
 976     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 977         assert_eq!(
 978             in_lhs.layout().ty,
 979             in_rhs.layout().ty,
 980             "checked int binop requires lhs and rhs of same type"
 981         );
 982     }
 983
 984     let lhs = in_lhs.load_scalar(fx);
 985     let rhs = in_rhs.load_scalar(fx);
 986     let res = match bin_op {
 987         BinOp::Add => fx.bcx.ins().iadd(lhs, rhs),
 988         BinOp::Sub => fx.bcx.ins().isub(lhs, rhs),
 989         BinOp::Mul => fx.bcx.ins().imul(lhs, rhs),
 990         BinOp::Shl => fx.bcx.ins().ishl(lhs, rhs),
 991         BinOp::Shr => {
 992             if !signed {
 993                 fx.bcx.ins().ushr(lhs, rhs)
 994             } else {
 995                 fx.bcx.ins().sshr(lhs, rhs)
 996             }
 997         }
 998         _ => bug!(
 999             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
1000             bin_op,
1001             in_lhs,
1002             in_rhs
1003         ),
1004     };
1005
1006     // TODO: check for overflow
1007     let has_overflow = fx.bcx.ins().iconst(types::I8, 0);
1008
1009     let out_place = CPlace::new_stack_slot(fx, out_ty);
1010     let out_layout = out_place.layout();
1011     out_place.write_cvalue(fx, CValue::ByValPair(res, has_overflow, out_layout));
1012
1013     out_place.to_cvalue(fx)
1014 }
1015
1016 fn trans_float_binop<'a, 'tcx: 'a>(
1017     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1018     bin_op: BinOp,
1019     lhs: CValue<'tcx>,
1020     rhs: CValue<'tcx>,
1021     ty: Ty<'tcx>,
1022 ) -> CValue<'tcx> {
1023     let res = binop_match! {
1024         fx, bin_op, false, lhs, rhs, ty, "float";
1025         Add (_) fadd;
1026         Sub (_) fsub;
1027         Mul (_) fmul;
1028         Div (_) fdiv;
1029         Rem (_) custom(|| {
1030             assert_eq!(lhs.layout().ty, ty);
1031             assert_eq!(rhs.layout().ty, ty);
1032             match ty.sty {
1033                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
1034                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
1035                 _ => bug!(),
1036             }
1037         });
1038         BitXor (_) bxor;
1039         BitAnd (_) band;
1040         BitOr (_) bor;
1041         Shl (_) bug;
1042         Shr (_) bug;
1043
1044         Eq (_) fcmp(Equal);
1045         Lt (_) fcmp(LessThan);
1046         Le (_) fcmp(LessThanOrEqual);
1047         Ne (_) fcmp(NotEqual);
1048         Ge (_) fcmp(GreaterThanOrEqual);
1049         Gt (_) fcmp(GreaterThan);
1050
1051         Offset (_) bug;
1052     };
1053
1054     res
1055 }
1056
1057 fn trans_char_binop<'a, 'tcx: 'a>(
1058     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1059     bin_op: BinOp,
1060     lhs: CValue<'tcx>,
1061     rhs: CValue<'tcx>,
1062     ty: Ty<'tcx>,
1063 ) -> CValue<'tcx> {
1064     let res = binop_match! {
1065         fx, bin_op, false, lhs, rhs, ty, "char";
1066         Add (_) bug;
1067         Sub (_) bug;
1068         Mul (_) bug;
1069         Div (_) bug;
1070         Rem (_) bug;
1071         BitXor (_) bug;
1072         BitAnd (_) bug;
1073         BitOr (_) bug;
1074         Shl (_) bug;
1075         Shr (_) bug;
1076
1077         Eq (_) icmp(Equal);
1078         Lt (_) icmp(UnsignedLessThan);
1079         Le (_) icmp(UnsignedLessThanOrEqual);
1080         Ne (_) icmp(NotEqual);
1081         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1082         Gt (_) icmp(UnsignedGreaterThan);
1083
1084         Offset (_) bug;
1085     };
1086
1087     res
1088 }
1089
1090 fn trans_ptr_binop<'a, 'tcx: 'a>(
1091     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1092     bin_op: BinOp,
1093     lhs: CValue<'tcx>,
1094     rhs: CValue<'tcx>,
1095     ret_ty: Ty<'tcx>,
1096 ) -> CValue<'tcx> {
1097     let not_fat = match lhs.layout().ty.sty {
1098         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1099             ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
1100         }
1101         ty::FnPtr(..) => true,
1102         _ => bug!("trans_ptr_binop on non ptr"),
1103     };
1104     if not_fat {
1105         if let BinOp::Offset = bin_op {
1106             let (base, offset) = (lhs, rhs.load_scalar(fx));
1107             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
1108             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
1109             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
1110             let base_val = base.load_scalar(fx);
1111             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
1112             return CValue::ByVal(res, base.layout());
1113         }
1114
1115         binop_match! {
1116             fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1117             Add (_) bug;
1118             Sub (_) bug;
1119             Mul (_) bug;
1120             Div (_) bug;
1121             Rem (_) bug;
1122             BitXor (_) bug;
1123             BitAnd (_) bug;
1124             BitOr (_) bug;
1125             Shl (_) bug;
1126             Shr (_) bug;
1127
1128             Eq (_) icmp(Equal);
1129             Lt (_) icmp(UnsignedLessThan);
1130             Le (_) icmp(UnsignedLessThanOrEqual);
1131             Ne (_) icmp(NotEqual);
1132             Ge (_) icmp(UnsignedGreaterThanOrEqual);
1133             Gt (_) icmp(UnsignedGreaterThan);
1134
1135             Offset (_) bug; // Handled above
1136         }
1137     } else {
1138         let (lhs_ptr, lhs_extra) = lhs.load_scalar_pair(fx);
1139         let (rhs_ptr, rhs_extra) = rhs.load_scalar_pair(fx);
1140         let res = match bin_op {
1141             BinOp::Eq => {
1142                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1143                 let extra_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_extra, rhs_extra);
1144                 fx.bcx.ins().band(ptr_eq, extra_eq)
1145             }
1146             BinOp::Ne => {
1147                 let ptr_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_ptr, rhs_ptr);
1148                 let extra_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_extra, rhs_extra);
1149                 fx.bcx.ins().bor(ptr_ne, extra_ne)
1150             }
1151             _ => unimplemented!(
1152                 "trans_ptr_binop({:?}, <fat ptr>, <fat ptr>) not implemented",
1153                 bin_op
1154             ),
1155         };
1156
1157         assert_eq!(fx.tcx.types.bool, ret_ty);
1158         let ret_layout = fx.layout_of(ret_ty);
1159         CValue::ByVal(fx.bcx.ins().bint(types::I8, res), ret_layout)
1160     }
1161 }
1162
1163 pub fn trans_place<'a, 'tcx: 'a>(
1164     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1165     place: &Place<'tcx>,
1166 ) -> CPlace<'tcx> {
1167     match place {
1168         Place::Base(base) => match base {
1169             PlaceBase::Local(local) => fx.get_local_place(*local),
1170             PlaceBase::Static(static_) => match static_.kind {
1171                 StaticKind::Static(def_id) => {
1172                     crate::constant::codegen_static_ref(fx, def_id, static_.ty)
1173                 }
1174                 StaticKind::Promoted(promoted) => {
1175                     crate::constant::trans_promoted(fx, promoted, static_.ty)
1176                 }
1177             }
1178         }
1179         Place::Projection(projection) => {
1180             let base = trans_place(fx, &projection.base);
1181             match projection.elem {
1182                 ProjectionElem::Deref => base.place_deref(fx),
1183                 ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1184                 ProjectionElem::Index(local) => {
1185                     let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1186                     base.place_index(fx, index)
1187                 }
1188                 ProjectionElem::ConstantIndex {
1189                     offset,
1190                     min_length: _,
1191                     from_end,
1192                 } => {
1193                     let index = if !from_end {
1194                         fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1195                     } else {
1196                         let len = codegen_array_len(fx, base);
1197                         fx.bcx.ins().iadd_imm(len, -(offset as i64))
1198                     };
1199                     base.place_index(fx, index)
1200                 }
1201                 ProjectionElem::Subslice { from, to } => {
1202                     // These indices are generated by slice patterns.
1203                     // slice[from:-to] in Python terms.
1204
1205                     match base.layout().ty.sty {
1206                         ty::Array(elem_ty, len) => {
1207                             let elem_layout = fx.layout_of(elem_ty);
1208                             let ptr = base.to_addr(fx);
1209                             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx);
1210                             CPlace::Addr(
1211                                 fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1212                                 None,
1213                                 fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
1214                             )
1215                         }
1216                         ty::Slice(elem_ty) => {
1217                             let elem_layout = fx.layout_of(elem_ty);
1218                             let (ptr, len) = base.to_addr_maybe_unsized(fx);
1219                             let len = len.unwrap();
1220                             CPlace::Addr(
1221                                 fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1222                                 Some(fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64))),
1223                                 base.layout(),
1224                             )
1225                         }
1226                         _ => unreachable!(),
1227                     }
1228                 }
1229                 ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1230             }
1231         }
1232     }
1233 }
1234
1235 pub fn trans_operand<'a, 'tcx>(
1236     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1237     operand: &Operand<'tcx>,
1238 ) -> CValue<'tcx> {
1239     match operand {
1240         Operand::Move(place) | Operand::Copy(place) => {
1241             let cplace = trans_place(fx, place);
1242             cplace.to_cvalue(fx)
1243         }
1244         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1245     }
1246 }