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. Declare function
  68     let (name, sig) = get_function_name_and_sig(tcx, instance);
  69     let func_id = cx.module
  70         .declare_function(&name, linkage, &sig)
  71         .unwrap();
  72     let mut debug_context = cx.debug_context.as_mut().map(|debug_context| FunctionDebugContext::new(
  73         tcx,
  74         debug_context,
  75         mir,
  76         &name,
  77         &sig,
  78     ));
  79
  80     // Step 3. Make FunctionBuilder
  81     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
  82     let mut func_ctx = FunctionBuilderContext::new();
  83     let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
  84
  85     // Step 4. Predefine ebb's
  86     let start_ebb = bcx.create_ebb();
  87     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
  88     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
  89         ebb_map.insert(bb, bcx.create_ebb());
  90     }
  91
  92     // Step 5. Make FunctionCx
  93     let pointer_type = cx.module.target_config().pointer_type();
  94     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
  95
  96     let mut fx = FunctionCx {
  97         tcx,
  98         module: cx.module,
  99         pointer_type,
 100
 101         instance,
 102         mir,
 103
 104         bcx,
 105         ebb_map,
 106         local_map: HashMap::new(),
 107
 108         clif_comments,
 109         constants: &mut cx.ccx,
 110         caches: &mut cx.caches,
 111         source_info_set: indexmap::IndexSet::new(),
 112     };
 113
 114     // Step 6. Codegen function
 115     with_unimpl_span(fx.mir.span, || {
 116         crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
 117         codegen_fn_content(&mut fx);
 118     });
 119     let source_info_set = fx.source_info_set.clone();
 120
 121     // Step 7. Write function to file for debugging
 122     #[cfg(debug_assertions)]
 123     fx.write_clif_file();
 124
 125     // Step 8. Verify function
 126     verify_func(tcx, fx.clif_comments, &func);
 127
 128     // Step 9. Define function
 129     cx.caches.context.func = func;
 130     cx.module
 131         .define_function_peek_compiled(func_id, &mut cx.caches.context, |size, context, isa| {
 132             debug_context.as_mut().map(|x| x.define(tcx, size, context, isa, &source_info_set));
 133         })
 134         .unwrap();
 135     //let module = &mut cx.module;
 136     //let caches = &cx.caches;
 137     cx.caches.context.clear();
 138 }
 139
 140 fn verify_func(tcx: TyCtxt, writer: crate::pretty_clif::CommentWriter, func: &Function) {
 141     let flags = settings::Flags::new(settings::builder());
 142     match ::cranelift::codegen::verify_function(&func, &flags) {
 143         Ok(_) => {}
 144         Err(err) => {
 145             tcx.sess.err(&format!("{:?}", err));
 146             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 147                 &func,
 148                 None,
 149                 Some(Box::new(&writer)),
 150                 err,
 151             );
 152             tcx.sess
 153                 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
 154         }
 155     }
 156 }
 157
 158 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 159     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 160         if bb_data.is_cleanup {
 161             // Unwinding after panicking is not supported
 162             continue;
 163         }
 164
 165         let ebb = fx.get_ebb(bb);
 166         fx.bcx.switch_to_block(ebb);
 167
 168         fx.bcx.ins().nop();
 169         for stmt in &bb_data.statements {
 170             fx.set_debug_loc(stmt.source_info);
 171             trans_stmt(fx, ebb, stmt);
 172         }
 173
 174         #[cfg(debug_assertions)]
 175         {
 176             let mut terminator_head = "\n".to_string();
 177             bb_data
 178                 .terminator()
 179                 .kind
 180                 .fmt_head(&mut terminator_head)
 181                 .unwrap();
 182             let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 183             fx.add_comment(inst, terminator_head);
 184         }
 185
 186         fx.set_debug_loc(bb_data.terminator().source_info);
 187
 188         match &bb_data.terminator().kind {
 189             TerminatorKind::Goto { target } => {
 190                 let ebb = fx.get_ebb(*target);
 191                 fx.bcx.ins().jump(ebb, &[]);
 192             }
 193             TerminatorKind::Return => {
 194                 crate::abi::codegen_return(fx);
 195             }
 196             TerminatorKind::Assert {
 197                 cond,
 198                 expected,
 199                 msg: _,
 200                 target,
 201                 cleanup: _,
 202             } => {
 203                 let cond = trans_operand(fx, cond).load_scalar(fx);
 204                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 205                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 206                 let target = fx.get_ebb(*target);
 207                 if *expected {
 208                     fx.bcx.ins().brnz(cond, target, &[]);
 209                 } else {
 210                     fx.bcx.ins().brz(cond, target, &[]);
 211                 };
 212                 trap_panic(&mut fx.bcx);
 213             }
 214
 215             TerminatorKind::SwitchInt {
 216                 discr,
 217                 switch_ty: _,
 218                 values,
 219                 targets,
 220             } => {
 221                 let discr = trans_operand(fx, discr).load_scalar(fx);
 222                 let mut switch = ::cranelift::frontend::Switch::new();
 223                 for (i, value) in values.iter().enumerate() {
 224                     let ebb = fx.get_ebb(targets[i]);
 225                     switch.set_entry(*value as u64, ebb);
 226                 }
 227                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 228                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 229             }
 230             TerminatorKind::Call {
 231                 func,
 232                 args,
 233                 destination,
 234                 cleanup: _,
 235                 from_hir_call: _,
 236             } => {
 237                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 238             }
 239             TerminatorKind::Resume | TerminatorKind::Abort | TerminatorKind::Unreachable => {
 240                 trap_unreachable(&mut fx.bcx);
 241             }
 242             TerminatorKind::Yield { .. }
 243             | TerminatorKind::FalseEdges { .. }
 244             | TerminatorKind::FalseUnwind { .. }
 245             | TerminatorKind::DropAndReplace { .. } => {
 246                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 247             }
 248             TerminatorKind::Drop {
 249                 location,
 250                 target,
 251                 unwind: _,
 252             } => {
 253                 let ty = location.ty(fx.mir, fx.tcx).to_ty(fx.tcx);
 254                 let ty = fx.monomorphize(&ty);
 255                 let drop_fn = crate::rustc_mir::monomorphize::resolve_drop_in_place(fx.tcx, ty);
 256
 257                 if let ty::InstanceDef::DropGlue(_, None) = drop_fn.def {
 258                     // we don't actually need to drop anything
 259                 } else {
 260                     let drop_place = trans_place(fx, location);
 261                     let arg_place = CPlace::new_stack_slot(
 262                         fx,
 263                         fx.tcx.mk_ref(
 264                             &ty::RegionKind::ReErased,
 265                             TypeAndMut {
 266                                 ty,
 267                                 mutbl: crate::rustc::hir::Mutability::MutMutable,
 268                             },
 269                         ),
 270                     );
 271                     drop_place.write_place_ref(fx, arg_place);
 272                     match ty.sty {
 273                         ty::Dynamic(..) => {
 274                             fx.tcx.sess.warn("Drop for trait object");
 275                         }
 276                         _ => {
 277                             let drop_fn_ty = drop_fn.ty(fx.tcx);
 278                             let arg_value = arg_place.to_cvalue(fx);
 279                             crate::abi::codegen_call_inner(
 280                                 fx,
 281                                 None,
 282                                 drop_fn_ty,
 283                                 vec![arg_value],
 284                                 None,
 285                             );
 286                         }
 287                     }
 288                     /*
 289                     let (args1, args2);
 290                     /*let mut args = if let Some(llextra) = place.llextra {
 291                         args2 = [place.llval, llextra];
 292                         &args2[..]
 293                     } else {
 294                         args1 = [place.llval];
 295                         &args1[..]
 296                     };*/
 297                     let (drop_fn, fn_ty) = match ty.sty {
 298                     ty::Dynamic(..) => {
 299                     let fn_ty = drop_fn.ty(bx.cx.tcx);
 300                     let sig = common::ty_fn_sig(bx.cx, fn_ty);
 301                     let sig = bx.tcx().normalize_erasing_late_bound_regions(
 302                     ty::ParamEnv::reveal_all(),
 303                     &sig,
 304                     );
 305                     let fn_ty = FnType::new_vtable(bx.cx, sig, &[]);
 306                     let vtable = args[1];
 307                     args = &args[..1];
 308                     (meth::DESTRUCTOR.get_fn(&bx, vtable, &fn_ty), fn_ty)
 309                     }
 310                     _ => {
 311                     let value = place.to_cvalue(fx);
 312                     (callee::get_fn(bx.cx, drop_fn),
 313                     FnType::of_instance(bx.cx, &drop_fn))
 314                     }
 315                     };
 316                     do_call(self, bx, fn_ty, drop_fn, args,
 317                     Some((ReturnDest::Nothing, target)),
 318                     unwind);*/
 319                 }
 320
 321                 let target_ebb = fx.get_ebb(*target);
 322                 fx.bcx.ins().jump(target_ebb, &[]);
 323             }
 324             TerminatorKind::GeneratorDrop => {
 325                 unimplemented!("terminator GeneratorDrop");
 326             }
 327         };
 328     }
 329
 330     fx.bcx.seal_all_blocks();
 331     fx.bcx.finalize();
 332 }
 333
 334 fn trans_stmt<'a, 'tcx: 'a>(
 335     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 336     cur_ebb: Ebb,
 337     stmt: &Statement<'tcx>,
 338 ) {
 339     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 340
 341     fx.set_debug_loc(stmt.source_info);
 342
 343     #[cfg(debug_assertions)]
 344     match &stmt.kind {
 345         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 346         _ => {
 347             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 348             fx.add_comment(inst, format!("{:?}", stmt));
 349         }
 350     }
 351
 352     match &stmt.kind {
 353         StatementKind::SetDiscriminant {
 354             place,
 355             variant_index,
 356         } => {
 357             let place = trans_place(fx, place);
 358             let layout = place.layout();
 359             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 360                 return;
 361             }
 362             match layout.variants {
 363                 layout::Variants::Single { index } => {
 364                     assert_eq!(index, *variant_index);
 365                 }
 366                 layout::Variants::Tagged { .. } => {
 367                     let ptr = place.place_field(fx, mir::Field::new(0));
 368                     let to = layout
 369                         .ty
 370                         .ty_adt_def()
 371                         .unwrap()
 372                         .discriminant_for_variant(fx.tcx, *variant_index)
 373                         .val;
 374                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 375                     ptr.write_cvalue(fx, discr);
 376                 }
 377                 layout::Variants::NicheFilling {
 378                     dataful_variant,
 379                     ref niche_variants,
 380                     niche_start,
 381                     ..
 382                 } => {
 383                     if *variant_index != dataful_variant {
 384                         let niche = place.place_field(fx, mir::Field::new(0));
 385                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 386                         let niche_value =
 387                             ((variant_index.as_u32() - niche_variants.start().as_u32()) as u128)
 388                                 .wrapping_add(niche_start);
 389                         // FIXME(eddyb) Check the actual primitive type here.
 390                         let niche_llval = if niche_value == 0 {
 391                             CValue::const_val(fx, niche.layout().ty, 0)
 392                         } else {
 393                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 394                         };
 395                         niche.write_cvalue(fx, niche_llval);
 396                     }
 397                 }
 398             }
 399         }
 400         StatementKind::Assign(to_place, rval) => {
 401             let lval = trans_place(fx, to_place);
 402             let dest_layout = lval.layout();
 403             match &**rval {
 404                 Rvalue::Use(operand) => {
 405                     let val = trans_operand(fx, operand);
 406                     lval.write_cvalue(fx, val);
 407                 }
 408                 Rvalue::Ref(_, _, place) => {
 409                     let place = trans_place(fx, place);
 410                     place.write_place_ref(fx, lval);
 411                 }
 412                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 413                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 414                     let lhs = trans_operand(fx, lhs);
 415                     let rhs = trans_operand(fx, rhs);
 416
 417                     let res = match ty.sty {
 418                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 419                         ty::Uint(_) => {
 420                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 421                         }
 422                         ty::Int(_) => {
 423                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 424                         }
 425                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 426                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 427                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 428                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 429                     };
 430                     lval.write_cvalue(fx, res);
 431                 }
 432                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 433                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 434                     let lhs = trans_operand(fx, lhs);
 435                     let rhs = trans_operand(fx, rhs);
 436
 437                     let res = match ty.sty {
 438                         ty::Uint(_) => {
 439                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 440                         }
 441                         ty::Int(_) => {
 442                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 443                         }
 444                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 445                     };
 446                     lval.write_cvalue(fx, res);
 447                 }
 448                 Rvalue::UnaryOp(un_op, operand) => {
 449                     let operand = trans_operand(fx, operand);
 450                     let layout = operand.layout();
 451                     let val = operand.load_scalar(fx);
 452                     let res = match un_op {
 453                         UnOp::Not => {
 454                             match layout.ty.sty {
 455                                 ty::Bool => {
 456                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 457                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 458                                     fx.bcx.ins().bint(types::I8, res)
 459                                 }
 460                                 ty::Uint(_) | ty::Int(_) => fx.bcx.ins().bnot(val),
 461                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 462                             }
 463                         }
 464                         UnOp::Neg => match layout.ty.sty {
 465                             ty::Int(_) => {
 466                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 467                                 let zero = fx.bcx.ins().iconst(clif_ty, 0);
 468                                 fx.bcx.ins().isub(zero, val)
 469                             }
 470                             ty::Float(_) => fx.bcx.ins().fneg(val),
 471                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 472                         },
 473                     };
 474                     lval.write_cvalue(fx, CValue::ByVal(res, layout));
 475                 }
 476                 Rvalue::Cast(CastKind::ReifyFnPointer, operand, ty) => {
 477                     let layout = fx.layout_of(ty);
 478                     match fx.monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx)).sty {
 479                         ty::FnDef(def_id, substs) => {
 480                             let func_ref = fx.get_function_ref(
 481                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs).unwrap(),
 482                             );
 483                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 484                             lval.write_cvalue(fx, CValue::ByVal(func_addr, layout));
 485                         }
 486                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 487                     }
 488                 }
 489                 Rvalue::Cast(CastKind::UnsafeFnPointer, operand, ty) => {
 490                     let operand = trans_operand(fx, operand);
 491                     let layout = fx.layout_of(ty);
 492                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 493                 }
 494                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 495                     let operand = trans_operand(fx, operand);
 496                     let from_ty = operand.layout().ty;
 497                     match (&from_ty.sty, &to_ty.sty) {
 498                         (ty::Ref(..), ty::Ref(..))
 499                         | (ty::Ref(..), ty::RawPtr(..))
 500                         | (ty::RawPtr(..), ty::Ref(..))
 501                         | (ty::RawPtr(..), ty::RawPtr(..))
 502                         | (ty::FnPtr(..), ty::RawPtr(..)) => {
 503                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 504                         }
 505                         (ty::RawPtr(..), ty::Uint(_))
 506                         | (ty::RawPtr(..), ty::Int(_))
 507                         | (ty::FnPtr(..), ty::Uint(_))
 508                             if to_ty.sty == fx.tcx.types.usize.sty
 509                                 || to_ty.sty == fx.tcx.types.isize.sty
 510                                 || fx.clif_type(to_ty).unwrap() == pointer_ty(fx.tcx) =>
 511                         {
 512                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 513                         }
 514                         (ty::Uint(_), ty::RawPtr(..)) if from_ty.sty == fx.tcx.types.usize.sty => {
 515                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 516                         }
 517                         (ty::Char, ty::Uint(_))
 518                         | (ty::Uint(_), ty::Char)
 519                         | (ty::Uint(_), ty::Int(_))
 520                         | (ty::Uint(_), ty::Uint(_)) => {
 521                             let from = operand.load_scalar(fx);
 522                             let res = crate::common::clif_intcast(
 523                                 fx,
 524                                 from,
 525                                 fx.clif_type(to_ty).unwrap(),
 526                                 false,
 527                             );
 528                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 529                         }
 530                         (ty::Int(_), ty::Int(_)) | (ty::Int(_), ty::Uint(_)) => {
 531                             let from = operand.load_scalar(fx);
 532                             let res = crate::common::clif_intcast(
 533                                 fx,
 534                                 from,
 535                                 fx.clif_type(to_ty).unwrap(),
 536                                 true,
 537                             );
 538                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 539                         }
 540                         (ty::Float(from_flt), ty::Float(to_flt)) => {
 541                             let from = operand.load_scalar(fx);
 542                             let res = match (from_flt, to_flt) {
 543                                 (FloatTy::F32, FloatTy::F64) => {
 544                                     fx.bcx.ins().fpromote(types::F64, from)
 545                                 }
 546                                 (FloatTy::F64, FloatTy::F32) => {
 547                                     fx.bcx.ins().fdemote(types::F32, from)
 548                                 }
 549                                 _ => from,
 550                             };
 551                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 552                         }
 553                         (ty::Int(_), ty::Float(_)) => {
 554                             let from_ty = fx.clif_type(from_ty).unwrap();
 555                             let from = operand.load_scalar(fx);
 556                             // FIXME missing encoding for fcvt_from_sint.f32.i8
 557                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 558                                 fx.bcx.ins().sextend(types::I32, from)
 559                             } else {
 560                                 from
 561                             };
 562                             let f_type = fx.clif_type(to_ty).unwrap();
 563                             let res = fx.bcx.ins().fcvt_from_sint(f_type, from);
 564                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 565                         }
 566                         (ty::Uint(_), ty::Float(_)) => {
 567                             let from_ty = fx.clif_type(from_ty).unwrap();
 568                             let from = operand.load_scalar(fx);
 569                             // FIXME missing encoding for fcvt_from_uint.f32.i8
 570                             let from = if from_ty == types::I8 || from_ty == types::I16 {
 571                                 fx.bcx.ins().uextend(types::I32, from)
 572                             } else {
 573                                 from
 574                             };
 575                             let f_type = fx.clif_type(to_ty).unwrap();
 576                             let res = fx.bcx.ins().fcvt_from_uint(f_type, from);
 577                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 578                         }
 579                         (ty::Bool, ty::Uint(_)) | (ty::Bool, ty::Int(_)) => {
 580                             let to_ty = fx.clif_type(to_ty).unwrap();
 581                             let from = operand.load_scalar(fx);
 582                             let res = if to_ty != types::I8 {
 583                                 fx.bcx.ins().uextend(to_ty, from)
 584                             } else {
 585                                 from
 586                             };
 587                             lval.write_cvalue(fx, CValue::ByVal(res, dest_layout));
 588                         }
 589                         (ty::Adt(adt_def, _substs), ty::Uint(_)) | (ty::Adt(adt_def, _substs), ty::Int(_)) if adt_def.is_enum() => {
 590                             let discr = trans_get_discriminant(fx, operand, fx.layout_of(to_ty));
 591                             lval.write_cvalue(fx, discr);
 592                         }
 593                         _ => unimpl!("rval misc {:?} {:?}", from_ty, to_ty),
 594                     }
 595                 }
 596                 Rvalue::Cast(CastKind::ClosureFnPointer, operand, ty) => {
 597                     unimplemented!("rval closure_fn_ptr {:?} {:?}", operand, ty)
 598                 }
 599                 Rvalue::Cast(CastKind::Unsize, operand, _ty) => {
 600                     let operand = trans_operand(fx, operand);
 601                     operand.unsize_value(fx, lval);
 602                 }
 603                 Rvalue::Discriminant(place) => {
 604                     let place = trans_place(fx, place).to_cvalue(fx);
 605                     let discr = trans_get_discriminant(fx, place, dest_layout);
 606                     lval.write_cvalue(fx, discr);
 607                 }
 608                 Rvalue::Repeat(operand, times) => {
 609                     let operand = trans_operand(fx, operand);
 610                     for i in 0..*times {
 611                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 612                         let to = lval.place_index(fx, index);
 613                         to.write_cvalue(fx, operand);
 614                     }
 615                 }
 616                 Rvalue::Len(place) => {
 617                     let place = trans_place(fx, place);
 618                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 619                     let len = codegen_array_len(fx, place);
 620                     lval.write_cvalue(fx, CValue::ByVal(len, usize_layout));
 621                 }
 622                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 623                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 624
 625                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 626                     let layout = fx.layout_of(content_ty);
 627                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 628                     let llalign = fx
 629                         .bcx
 630                         .ins()
 631                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 632                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 633
 634                     // Allocate space:
 635                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 636                         Ok(id) => id,
 637                         Err(s) => {
 638                             fx.tcx
 639                                 .sess
 640                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 641                         }
 642                     };
 643                     let instance = ty::Instance::mono(fx.tcx, def_id);
 644                     let func_ref = fx.get_function_ref(instance);
 645                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 646                     let ptr = fx.bcx.inst_results(call)[0];
 647                     lval.write_cvalue(fx, CValue::ByVal(ptr, box_layout));
 648                 }
 649                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 650                     assert!(lval
 651                         .layout()
 652                         .ty
 653                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 654                     let ty_size = fx.layout_of(ty).size.bytes();
 655                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 656                     lval.write_cvalue(fx, val);
 657                 }
 658                 Rvalue::Aggregate(kind, operands) => match **kind {
 659                     AggregateKind::Array(_ty) => {
 660                         for (i, operand) in operands.into_iter().enumerate() {
 661                             let operand = trans_operand(fx, operand);
 662                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 663                             let to = lval.place_index(fx, index);
 664                             to.write_cvalue(fx, operand);
 665                         }
 666                     }
 667                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 668                 },
 669             }
 670         }
 671         StatementKind::StorageLive(_)
 672         | StatementKind::StorageDead(_)
 673         | StatementKind::Nop
 674         | StatementKind::FakeRead(..)
 675         | StatementKind::Retag { .. }
 676         | StatementKind::AscribeUserType(..) => {}
 677
 678         StatementKind::InlineAsm { .. } => unimpl!("Inline assembly is not supported"),
 679     }
 680 }
 681
 682 fn codegen_array_len<'a, 'tcx: 'a>(
 683     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 684     place: CPlace<'tcx>,
 685 ) -> Value {
 686     match place.layout().ty.sty {
 687         ty::Array(_elem_ty, len) => {
 688             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx) as i64;
 689             fx.bcx.ins().iconst(fx.pointer_type, len)
 690         }
 691         ty::Slice(_elem_ty) => {
 692             place.to_addr_maybe_unsized(fx).1.expect("Length metadata for slice place")
 693         }
 694         _ => bug!("Rvalue::Len({:?})", place),
 695     }
 696 }
 697
 698 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 699     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 700     value: CValue<'tcx>,
 701     dest_layout: TyLayout<'tcx>,
 702 ) -> CValue<'tcx> {
 703     let layout = value.layout();
 704
 705     if layout.abi == layout::Abi::Uninhabited {
 706         trap_unreachable(&mut fx.bcx);
 707     }
 708     match layout.variants {
 709         layout::Variants::Single { index } => {
 710             let discr_val = layout
 711                 .ty
 712                 .ty_adt_def()
 713                 .map_or(index.as_u32() as u128, |def| {
 714                     def.discriminant_for_variant(fx.tcx, index).val
 715                 });
 716             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 717         }
 718         layout::Variants::Tagged { .. } | layout::Variants::NicheFilling { .. } => {}
 719     }
 720
 721     let discr = value.value_field(fx, mir::Field::new(0));
 722     let discr_ty = discr.layout().ty;
 723     let lldiscr = discr.load_scalar(fx);
 724     match layout.variants {
 725         layout::Variants::Single { .. } => bug!(),
 726         layout::Variants::Tagged { ref tag, .. } => {
 727             let signed = match tag.value {
 728                 layout::Int(_, signed) => signed,
 729                 _ => false,
 730             };
 731             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 732             return CValue::ByVal(val, dest_layout);
 733         }
 734         layout::Variants::NicheFilling {
 735             dataful_variant,
 736             ref niche_variants,
 737             niche_start,
 738             ..
 739         } => {
 740             let niche_llty = fx.clif_type(discr_ty).unwrap();
 741             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 742             if niche_variants.start() == niche_variants.end() {
 743                 let b = fx
 744                     .bcx
 745                     .ins()
 746                     .icmp_imm(IntCC::Equal, lldiscr, niche_start as u64 as i64);
 747                 let if_true = fx
 748                     .bcx
 749                     .ins()
 750                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 751                 let if_false = fx
 752                     .bcx
 753                     .ins()
 754                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 755                 let val = fx.bcx.ins().select(b, if_true, if_false);
 756                 return CValue::ByVal(val, dest_layout);
 757             } else {
 758                 // Rebase from niche values to discriminant values.
 759                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 760                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 761                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 762                 let b = fx.bcx.ins().icmp_imm(
 763                     IntCC::UnsignedLessThanOrEqual,
 764                     lldiscr,
 765                     niche_variants.end().as_u32() as i64,
 766                 );
 767                 let if_true =
 768                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 769                 let if_false = fx
 770                     .bcx
 771                     .ins()
 772                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 773                 let val = fx.bcx.ins().select(b, if_true, if_false);
 774                 return CValue::ByVal(val, dest_layout);
 775             }
 776         }
 777     }
 778 }
 779
 780 macro_rules! binop_match {
 781     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 782         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 783     };
 784     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 785         assert_eq!($fx.tcx.types.bool, $ret_ty);
 786         let ret_layout = $fx.layout_of($ret_ty);
 787
 788         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 789         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 790     }};
 791     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 792         assert_eq!($fx.tcx.types.bool, $ret_ty);
 793         let ret_layout = $fx.layout_of($ret_ty);
 794         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 795         CValue::ByVal($fx.bcx.ins().bint(types::I8, b), ret_layout)
 796     }};
 797     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 798         $body
 799     }};
 800     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 801         let ret_layout = $fx.layout_of($ret_ty);
 802         CValue::ByVal($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 803     }};
 804     (
 805         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 806         $(
 807             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 808         )*
 809     ) => {{
 810         let lhs = $lhs.load_scalar($fx);
 811         let rhs = $rhs.load_scalar($fx);
 812         match ($bin_op, $signed) {
 813             $(
 814                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 815             )*
 816         }
 817     }}
 818 }
 819
 820 fn trans_bool_binop<'a, 'tcx: 'a>(
 821     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 822     bin_op: BinOp,
 823     lhs: CValue<'tcx>,
 824     rhs: CValue<'tcx>,
 825     ty: Ty<'tcx>,
 826 ) -> CValue<'tcx> {
 827     let res = binop_match! {
 828         fx, bin_op, false, lhs, rhs, ty, "bool";
 829         Add (_) bug;
 830         Sub (_) bug;
 831         Mul (_) bug;
 832         Div (_) bug;
 833         Rem (_) bug;
 834         BitXor (_) bxor;
 835         BitAnd (_) band;
 836         BitOr (_) bor;
 837         Shl (_) bug;
 838         Shr (_) bug;
 839
 840         Eq (_) icmp(Equal);
 841         Lt (_) icmp(UnsignedLessThan);
 842         Le (_) icmp(UnsignedLessThanOrEqual);
 843         Ne (_) icmp(NotEqual);
 844         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 845         Gt (_) icmp(UnsignedGreaterThan);
 846
 847         Offset (_) bug;
 848     };
 849
 850     res
 851 }
 852
 853 pub fn trans_int_binop<'a, 'tcx: 'a>(
 854     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 855     bin_op: BinOp,
 856     lhs: CValue<'tcx>,
 857     rhs: CValue<'tcx>,
 858     out_ty: Ty<'tcx>,
 859     signed: bool,
 860 ) -> CValue<'tcx> {
 861     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 862         assert_eq!(
 863             lhs.layout().ty,
 864             rhs.layout().ty,
 865             "int binop requires lhs and rhs of same type"
 866         );
 867     }
 868     binop_match! {
 869         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 870         Add (_) iadd;
 871         Sub (_) isub;
 872         Mul (_) imul;
 873         Div (false) udiv;
 874         Div (true) sdiv;
 875         Rem (false) urem;
 876         Rem (true) srem;
 877         BitXor (_) bxor;
 878         BitAnd (_) band;
 879         BitOr (_) bor;
 880         Shl (_) ishl;
 881         Shr (false) ushr;
 882         Shr (true) sshr;
 883
 884         Eq (_) icmp(Equal);
 885         Lt (false) icmp(UnsignedLessThan);
 886         Lt (true) icmp(SignedLessThan);
 887         Le (false) icmp(UnsignedLessThanOrEqual);
 888         Le (true) icmp(SignedLessThanOrEqual);
 889         Ne (_) icmp(NotEqual);
 890         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 891         Ge (true) icmp(SignedGreaterThanOrEqual);
 892         Gt (false) icmp(UnsignedGreaterThan);
 893         Gt (true) icmp(SignedGreaterThan);
 894
 895         Offset (_) bug;
 896     }
 897 }
 898
 899 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 900     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 901     bin_op: BinOp,
 902     in_lhs: CValue<'tcx>,
 903     in_rhs: CValue<'tcx>,
 904     out_ty: Ty<'tcx>,
 905     signed: bool,
 906 ) -> CValue<'tcx> {
 907     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 908         assert_eq!(
 909             in_lhs.layout().ty,
 910             in_rhs.layout().ty,
 911             "checked int binop requires lhs and rhs of same type"
 912         );
 913     }
 914
 915     let lhs = in_lhs.load_scalar(fx);
 916     let rhs = in_rhs.load_scalar(fx);
 917     let res = match bin_op {
 918         BinOp::Add => fx.bcx.ins().iadd(lhs, rhs),
 919         BinOp::Sub => fx.bcx.ins().isub(lhs, rhs),
 920         BinOp::Mul => fx.bcx.ins().imul(lhs, rhs),
 921         BinOp::Shl => fx.bcx.ins().ishl(lhs, rhs),
 922         BinOp::Shr => {
 923             if !signed {
 924                 fx.bcx.ins().ushr(lhs, rhs)
 925             } else {
 926                 fx.bcx.ins().sshr(lhs, rhs)
 927             }
 928         }
 929         _ => bug!(
 930             "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 931             bin_op,
 932             in_lhs,
 933             in_rhs
 934         ),
 935     };
 936
 937     // TODO: check for overflow
 938     let has_overflow = fx.bcx.ins().iconst(types::I8, 0);
 939
 940     let out_place = CPlace::new_stack_slot(fx, out_ty);
 941     let out_layout = out_place.layout();
 942     out_place.write_cvalue(fx, CValue::ByValPair(res, has_overflow, out_layout));
 943
 944     out_place.to_cvalue(fx)
 945 }
 946
 947 fn trans_float_binop<'a, 'tcx: 'a>(
 948     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 949     bin_op: BinOp,
 950     lhs: CValue<'tcx>,
 951     rhs: CValue<'tcx>,
 952     ty: Ty<'tcx>,
 953 ) -> CValue<'tcx> {
 954     let res = binop_match! {
 955         fx, bin_op, false, lhs, rhs, ty, "float";
 956         Add (_) fadd;
 957         Sub (_) fsub;
 958         Mul (_) fmul;
 959         Div (_) fdiv;
 960         Rem (_) custom(|| {
 961             assert_eq!(lhs.layout().ty, ty);
 962             assert_eq!(rhs.layout().ty, ty);
 963             match ty.sty {
 964                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
 965                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
 966                 _ => bug!(),
 967             }
 968         });
 969         BitXor (_) bxor;
 970         BitAnd (_) band;
 971         BitOr (_) bor;
 972         Shl (_) bug;
 973         Shr (_) bug;
 974
 975         Eq (_) fcmp(Equal);
 976         Lt (_) fcmp(LessThan);
 977         Le (_) fcmp(LessThanOrEqual);
 978         Ne (_) fcmp(NotEqual);
 979         Ge (_) fcmp(GreaterThanOrEqual);
 980         Gt (_) fcmp(GreaterThan);
 981
 982         Offset (_) bug;
 983     };
 984
 985     res
 986 }
 987
 988 fn trans_char_binop<'a, 'tcx: 'a>(
 989     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 990     bin_op: BinOp,
 991     lhs: CValue<'tcx>,
 992     rhs: CValue<'tcx>,
 993     ty: Ty<'tcx>,
 994 ) -> CValue<'tcx> {
 995     let res = binop_match! {
 996         fx, bin_op, false, lhs, rhs, ty, "char";
 997         Add (_) bug;
 998         Sub (_) bug;
 999         Mul (_) bug;
1000         Div (_) bug;
1001         Rem (_) bug;
1002         BitXor (_) bug;
1003         BitAnd (_) bug;
1004         BitOr (_) bug;
1005         Shl (_) bug;
1006         Shr (_) bug;
1007
1008         Eq (_) icmp(Equal);
1009         Lt (_) icmp(UnsignedLessThan);
1010         Le (_) icmp(UnsignedLessThanOrEqual);
1011         Ne (_) icmp(NotEqual);
1012         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1013         Gt (_) icmp(UnsignedGreaterThan);
1014
1015         Offset (_) bug;
1016     };
1017
1018     res
1019 }
1020
1021 fn trans_ptr_binop<'a, 'tcx: 'a>(
1022     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1023     bin_op: BinOp,
1024     lhs: CValue<'tcx>,
1025     rhs: CValue<'tcx>,
1026     ret_ty: Ty<'tcx>,
1027 ) -> CValue<'tcx> {
1028     match lhs.layout().ty.sty {
1029         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1030             if ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()) {
1031                 binop_match! {
1032                     fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1033                     Add (_) bug;
1034                     Sub (_) bug;
1035                     Mul (_) bug;
1036                     Div (_) bug;
1037                     Rem (_) bug;
1038                     BitXor (_) bug;
1039                     BitAnd (_) bug;
1040                     BitOr (_) bug;
1041                     Shl (_) bug;
1042                     Shr (_) bug;
1043
1044                     Eq (_) icmp(Equal);
1045                     Lt (_) icmp(UnsignedLessThan);
1046                     Le (_) icmp(UnsignedLessThanOrEqual);
1047                     Ne (_) icmp(NotEqual);
1048                     Ge (_) icmp(UnsignedGreaterThanOrEqual);
1049                     Gt (_) icmp(UnsignedGreaterThan);
1050
1051                     Offset (_) iadd;
1052                 }
1053             } else {
1054                 let lhs = lhs.load_value_pair(fx).0;
1055                 let rhs = rhs.load_value_pair(fx).0;
1056                 let res = match bin_op {
1057                     BinOp::Eq => fx.bcx.ins().icmp(IntCC::Equal, lhs, rhs),
1058                     BinOp::Ne => fx.bcx.ins().icmp(IntCC::NotEqual, lhs, rhs),
1059                     _ => unimplemented!(
1060                         "trans_ptr_binop({:?}, <fat ptr>, <fat ptr>) not implemented",
1061                         bin_op
1062                     ),
1063                 };
1064
1065                 assert_eq!(fx.tcx.types.bool, ret_ty);
1066                 let ret_layout = fx.layout_of(ret_ty);
1067                 CValue::ByVal(fx.bcx.ins().bint(types::I8, res), ret_layout)
1068             }
1069         }
1070         _ => bug!("trans_ptr_binop on non ptr"),
1071     }
1072 }
1073
1074 pub fn trans_place<'a, 'tcx: 'a>(
1075     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1076     place: &Place<'tcx>,
1077 ) -> CPlace<'tcx> {
1078     match place {
1079         Place::Local(local) => fx.get_local_place(*local),
1080         Place::Promoted(promoted) => crate::constant::trans_promoted(fx, promoted.0),
1081         Place::Static(static_) => crate::constant::codegen_static_ref(fx, static_),
1082         Place::Projection(projection) => {
1083             let base = trans_place(fx, &projection.base);
1084             match projection.elem {
1085                 ProjectionElem::Deref => base.place_deref(fx),
1086                 ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1087                 ProjectionElem::Index(local) => {
1088                     let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1089                     base.place_index(fx, index)
1090                 }
1091                 ProjectionElem::ConstantIndex {
1092                     offset,
1093                     min_length: _,
1094                     from_end,
1095                 } => {
1096                     let index = if !from_end {
1097                         fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1098                     } else {
1099                         let len = codegen_array_len(fx, base);
1100                         fx.bcx.ins().iadd_imm(len, -(offset as i64))
1101                     };
1102                     base.place_index(fx, index)
1103                 }
1104                 ProjectionElem::Subslice { from, to } => unimpl!(
1105                     "projection subslice {:?} from {} to {}",
1106                     projection.base,
1107                     from,
1108                     to
1109                 ),
1110                 ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1111             }
1112         }
1113     }
1114 }
1115
1116 pub fn trans_operand<'a, 'tcx>(
1117     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1118     operand: &Operand<'tcx>,
1119 ) -> CValue<'tcx> {
1120     match operand {
1121         Operand::Move(place) | Operand::Copy(place) => {
1122             let cplace = trans_place(fx, place);
1123             cplace.to_cvalue(fx)
1124         }
1125         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1126     }
1127 }