compiler/rustc_hir_analysis/src/check/intrinsic.rs

   1 //! Type-checking for the rust-intrinsic and platform-intrinsic
   2 //! intrinsics that the compiler exposes.
   3
   4 use crate::errors::{
   5     UnrecognizedAtomicOperation, UnrecognizedIntrinsicFunction,
   6     WrongNumberOfGenericArgumentsToIntrinsic,
   7 };
   8 use crate::require_same_types;
   9
  10 use hir::def_id::DefId;
  11 use rustc_errors::{struct_span_err, DiagnosticMessage};
  12 use rustc_hir as hir;
  13 use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
  14 use rustc_middle::ty::{self, TyCtxt};
  15 use rustc_span::symbol::{kw, sym, Symbol};
  16 use rustc_target::spec::abi::Abi;
  17
  18 use std::iter;
  19
  20 fn equate_intrinsic_type<'tcx>(
  21     tcx: TyCtxt<'tcx>,
  22     it: &hir::ForeignItem<'_>,
  23     n_tps: usize,
  24     n_lts: usize,
  25     sig: ty::PolyFnSig<'tcx>,
  26 ) {
  27     let (own_counts, span) = match &it.kind {
  28         hir::ForeignItemKind::Fn(.., generics) => {
  29             let own_counts = tcx.generics_of(it.def_id.to_def_id()).own_counts();
  30             (own_counts, generics.span)
  31         }
  32         _ => {
  33             struct_span_err!(tcx.sess, it.span, E0622, "intrinsic must be a function")
  34                 .span_label(it.span, "expected a function")
  35                 .emit();
  36             return;
  37         }
  38     };
  39
  40     let gen_count_ok = |found: usize, expected: usize, descr: &str| -> bool {
  41         if found != expected {
  42             tcx.sess.emit_err(WrongNumberOfGenericArgumentsToIntrinsic {
  43                 span,
  44                 found,
  45                 expected,
  46                 descr,
  47             });
  48             false
  49         } else {
  50             true
  51         }
  52     };
  53
  54     if gen_count_ok(own_counts.lifetimes, n_lts, "lifetime")
  55         && gen_count_ok(own_counts.types, n_tps, "type")
  56         && gen_count_ok(own_counts.consts, 0, "const")
  57     {
  58         let fty = tcx.mk_fn_ptr(sig);
  59         let cause = ObligationCause::new(it.span, it.hir_id(), ObligationCauseCode::IntrinsicType);
  60         require_same_types(tcx, &cause, tcx.mk_fn_ptr(tcx.fn_sig(it.def_id)), fty);
  61     }
  62 }
  63
  64 /// Returns the unsafety of the given intrinsic.
  65 pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: DefId) -> hir::Unsafety {
  66     let has_safe_attr = match tcx.has_attr(intrinsic_id, sym::rustc_safe_intrinsic) {
  67         true => hir::Unsafety::Normal,
  68         false => hir::Unsafety::Unsafe,
  69     };
  70     let is_in_list = match tcx.item_name(intrinsic_id) {
  71         // When adding a new intrinsic to this list,
  72         // it's usually worth updating that intrinsic's documentation
  73         // to note that it's safe to call, since
  74         // safe extern fns are otherwise unprecedented.
  75         sym::abort
  76         | sym::assert_inhabited
  77         | sym::assert_zero_valid
  78         | sym::assert_uninit_valid
  79         | sym::size_of
  80         | sym::min_align_of
  81         | sym::needs_drop
  82         | sym::caller_location
  83         | sym::add_with_overflow
  84         | sym::sub_with_overflow
  85         | sym::mul_with_overflow
  86         | sym::wrapping_add
  87         | sym::wrapping_sub
  88         | sym::wrapping_mul
  89         | sym::saturating_add
  90         | sym::saturating_sub
  91         | sym::rotate_left
  92         | sym::rotate_right
  93         | sym::ctpop
  94         | sym::ctlz
  95         | sym::cttz
  96         | sym::bswap
  97         | sym::bitreverse
  98         | sym::discriminant_value
  99         | sym::type_id
 100         | sym::likely
 101         | sym::unlikely
 102         | sym::ptr_guaranteed_cmp
 103         | sym::minnumf32
 104         | sym::minnumf64
 105         | sym::maxnumf32
 106         | sym::rustc_peek
 107         | sym::maxnumf64
 108         | sym::type_name
 109         | sym::forget
 110         | sym::black_box
 111         | sym::variant_count
 112         | sym::ptr_mask => hir::Unsafety::Normal,
 113         _ => hir::Unsafety::Unsafe,
 114     };
 115
 116     if has_safe_attr != is_in_list {
 117         tcx.sess.struct_span_err(
 118             tcx.def_span(intrinsic_id),
 119             DiagnosticMessage::Str(format!(
 120                     "intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `{}`",
 121                     tcx.item_name(intrinsic_id)
 122         ))).emit();
 123     }
 124
 125     is_in_list
 126 }
 127
 128 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
 129 /// and in `library/core/src/intrinsics.rs`.
 130 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
 131     let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
 132     let intrinsic_id = it.def_id.to_def_id();
 133     let intrinsic_name = tcx.item_name(intrinsic_id);
 134     let name_str = intrinsic_name.as_str();
 135
 136     let bound_vars = tcx.mk_bound_variable_kinds(
 137         [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)]
 138             .iter()
 139             .copied(),
 140     );
 141     let mk_va_list_ty = |mutbl| {
 142         tcx.lang_items().va_list().map(|did| {
 143             let region = tcx.mk_region(ty::ReLateBound(
 144                 ty::INNERMOST,
 145                 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) },
 146             ));
 147             let env_region = tcx.mk_region(ty::ReLateBound(
 148                 ty::INNERMOST,
 149                 ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
 150             ));
 151             let va_list_ty = tcx.bound_type_of(did).subst(tcx, &[region.into()]);
 152             (tcx.mk_ref(env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
 153         })
 154     };
 155
 156     let (n_tps, n_lts, inputs, output, unsafety) = if name_str.starts_with("atomic_") {
 157         let split: Vec<&str> = name_str.split('_').collect();
 158         assert!(split.len() >= 2, "Atomic intrinsic in an incorrect format");
 159
 160         //We only care about the operation here
 161         let (n_tps, inputs, output) = match split[1] {
 162             "cxchg" | "cxchgweak" => (
 163                 1,
 164                 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
 165                 tcx.intern_tup(&[param(0), tcx.types.bool]),
 166             ),
 167             "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
 168             "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
 169
 170             "xchg" | "xadd" | "xsub" | "and" | "nand" | "or" | "xor" | "max" | "min" | "umax"
 171             | "umin" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], param(0)),
 172             "fence" | "singlethreadfence" => (0, Vec::new(), tcx.mk_unit()),
 173             op => {
 174                 tcx.sess.emit_err(UnrecognizedAtomicOperation { span: it.span, op });
 175                 return;
 176             }
 177         };
 178         (n_tps, 0, inputs, output, hir::Unsafety::Unsafe)
 179     } else {
 180         let unsafety = intrinsic_operation_unsafety(tcx, intrinsic_id);
 181         let (n_tps, inputs, output) = match intrinsic_name {
 182             sym::abort => (0, Vec::new(), tcx.types.never),
 183             sym::unreachable => (0, Vec::new(), tcx.types.never),
 184             sym::breakpoint => (0, Vec::new(), tcx.mk_unit()),
 185             sym::size_of | sym::pref_align_of | sym::min_align_of | sym::variant_count => {
 186                 (1, Vec::new(), tcx.types.usize)
 187             }
 188             sym::size_of_val | sym::min_align_of_val => {
 189                 (1, vec![tcx.mk_imm_ptr(param(0))], tcx.types.usize)
 190             }
 191             sym::rustc_peek => (1, vec![param(0)], param(0)),
 192             sym::caller_location => (0, vec![], tcx.caller_location_ty()),
 193             sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
 194                 (1, Vec::new(), tcx.mk_unit())
 195             }
 196             sym::forget => (1, vec![param(0)], tcx.mk_unit()),
 197             sym::transmute => (2, vec![param(0)], param(1)),
 198             sym::prefetch_read_data
 199             | sym::prefetch_write_data
 200             | sym::prefetch_read_instruction
 201             | sym::prefetch_write_instruction => (
 202                 1,
 203                 vec![
 204                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 205                     tcx.types.i32,
 206                 ],
 207                 tcx.mk_unit(),
 208             ),
 209             sym::drop_in_place => (1, vec![tcx.mk_mut_ptr(param(0))], tcx.mk_unit()),
 210             sym::needs_drop => (1, Vec::new(), tcx.types.bool),
 211
 212             sym::type_name => (1, Vec::new(), tcx.mk_static_str()),
 213             sym::type_id => (1, Vec::new(), tcx.types.u64),
 214             sym::offset | sym::arith_offset => (
 215                 1,
 216                 vec![
 217                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 218                     tcx.types.isize,
 219                 ],
 220                 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 221             ),
 222             sym::ptr_mask => (
 223                 1,
 224                 vec![
 225                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 226                     tcx.types.usize,
 227                 ],
 228                 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 229             ),
 230
 231             sym::copy | sym::copy_nonoverlapping => (
 232                 1,
 233                 vec![
 234                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 235                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
 236                     tcx.types.usize,
 237                 ],
 238                 tcx.mk_unit(),
 239             ),
 240             sym::volatile_copy_memory | sym::volatile_copy_nonoverlapping_memory => (
 241                 1,
 242                 vec![
 243                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
 244                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
 245                     tcx.types.usize,
 246                 ],
 247                 tcx.mk_unit(),
 248             ),
 249             sym::write_bytes | sym::volatile_set_memory => (
 250                 1,
 251                 vec![
 252                     tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
 253                     tcx.types.u8,
 254                     tcx.types.usize,
 255                 ],
 256                 tcx.mk_unit(),
 257             ),
 258             sym::sqrtf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 259             sym::sqrtf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 260             sym::powif32 => (0, vec![tcx.types.f32, tcx.types.i32], tcx.types.f32),
 261             sym::powif64 => (0, vec![tcx.types.f64, tcx.types.i32], tcx.types.f64),
 262             sym::sinf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 263             sym::sinf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 264             sym::cosf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 265             sym::cosf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 266             sym::powf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
 267             sym::powf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
 268             sym::expf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 269             sym::expf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 270             sym::exp2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
 271             sym::exp2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
 272             sym::logf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 273             sym::logf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 274             sym::log10f32 => (0, vec![tcx.types.f32], tcx.types.f32),
 275             sym::log10f64 => (0, vec![tcx.types.f64], tcx.types.f64),
 276             sym::log2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
 277             sym::log2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
 278             sym::fmaf32 => (0, vec![tcx.types.f32, tcx.types.f32, tcx.types.f32], tcx.types.f32),
 279             sym::fmaf64 => (0, vec![tcx.types.f64, tcx.types.f64, tcx.types.f64], tcx.types.f64),
 280             sym::fabsf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 281             sym::fabsf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 282             sym::minnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
 283             sym::minnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
 284             sym::maxnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
 285             sym::maxnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
 286             sym::copysignf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
 287             sym::copysignf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
 288             sym::floorf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 289             sym::floorf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 290             sym::ceilf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 291             sym::ceilf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 292             sym::truncf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 293             sym::truncf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 294             sym::rintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 295             sym::rintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 296             sym::nearbyintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 297             sym::nearbyintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 298             sym::roundf32 => (0, vec![tcx.types.f32], tcx.types.f32),
 299             sym::roundf64 => (0, vec![tcx.types.f64], tcx.types.f64),
 300
 301             sym::volatile_load | sym::unaligned_volatile_load => {
 302                 (1, vec![tcx.mk_imm_ptr(param(0))], param(0))
 303             }
 304             sym::volatile_store | sym::unaligned_volatile_store => {
 305                 (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit())
 306             }
 307
 308             sym::ctpop
 309             | sym::ctlz
 310             | sym::ctlz_nonzero
 311             | sym::cttz
 312             | sym::cttz_nonzero
 313             | sym::bswap
 314             | sym::bitreverse => (1, vec![param(0)], param(0)),
 315
 316             sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
 317                 (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
 318             }
 319
 320             sym::ptr_guaranteed_cmp => {
 321                 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.u8)
 322             }
 323
 324             sym::const_allocate => {
 325                 (0, vec![tcx.types.usize, tcx.types.usize], tcx.mk_mut_ptr(tcx.types.u8))
 326             }
 327             sym::const_deallocate => (
 328                 0,
 329                 vec![tcx.mk_mut_ptr(tcx.types.u8), tcx.types.usize, tcx.types.usize],
 330                 tcx.mk_unit(),
 331             ),
 332
 333             sym::ptr_offset_from => {
 334                 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.isize)
 335             }
 336             sym::ptr_offset_from_unsigned => {
 337                 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.usize)
 338             }
 339             sym::unchecked_div | sym::unchecked_rem | sym::exact_div => {
 340                 (1, vec![param(0), param(0)], param(0))
 341             }
 342             sym::unchecked_shl | sym::unchecked_shr | sym::rotate_left | sym::rotate_right => {
 343                 (1, vec![param(0), param(0)], param(0))
 344             }
 345             sym::unchecked_add | sym::unchecked_sub | sym::unchecked_mul => {
 346                 (1, vec![param(0), param(0)], param(0))
 347             }
 348             sym::wrapping_add | sym::wrapping_sub | sym::wrapping_mul => {
 349                 (1, vec![param(0), param(0)], param(0))
 350             }
 351             sym::saturating_add | sym::saturating_sub => (1, vec![param(0), param(0)], param(0)),
 352             sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
 353                 (1, vec![param(0), param(0)], param(0))
 354             }
 355             sym::float_to_int_unchecked => (2, vec![param(0)], param(1)),
 356
 357             sym::assume => (0, vec![tcx.types.bool], tcx.mk_unit()),
 358             sym::likely => (0, vec![tcx.types.bool], tcx.types.bool),
 359             sym::unlikely => (0, vec![tcx.types.bool], tcx.types.bool),
 360
 361             sym::discriminant_value => {
 362                 let assoc_items = tcx.associated_item_def_ids(
 363                     tcx.require_lang_item(hir::LangItem::DiscriminantKind, None),
 364                 );
 365                 let discriminant_def_id = assoc_items[0];
 366
 367                 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
 368                 (
 369                     1,
 370                     vec![
 371                         tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)),
 372                     ],
 373                     tcx.mk_projection(discriminant_def_id, tcx.mk_substs([param(0).into()].iter())),
 374                 )
 375             }
 376
 377             kw::Try => {
 378                 let mut_u8 = tcx.mk_mut_ptr(tcx.types.u8);
 379                 let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
 380                     iter::once(mut_u8),
 381                     tcx.mk_unit(),
 382                     false,
 383                     hir::Unsafety::Normal,
 384                     Abi::Rust,
 385                 ));
 386                 let catch_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
 387                     [mut_u8, mut_u8].iter().cloned(),
 388                     tcx.mk_unit(),
 389                     false,
 390                     hir::Unsafety::Normal,
 391                     Abi::Rust,
 392                 ));
 393                 (
 394                     0,
 395                     vec![tcx.mk_fn_ptr(try_fn_ty), mut_u8, tcx.mk_fn_ptr(catch_fn_ty)],
 396                     tcx.types.i32,
 397                 )
 398             }
 399
 400             sym::va_start | sym::va_end => match mk_va_list_ty(hir::Mutability::Mut) {
 401                 Some((va_list_ref_ty, _)) => (0, vec![va_list_ref_ty], tcx.mk_unit()),
 402                 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
 403             },
 404
 405             sym::va_copy => match mk_va_list_ty(hir::Mutability::Not) {
 406                 Some((va_list_ref_ty, va_list_ty)) => {
 407                     let va_list_ptr_ty = tcx.mk_mut_ptr(va_list_ty);
 408                     (0, vec![va_list_ptr_ty, va_list_ref_ty], tcx.mk_unit())
 409                 }
 410                 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
 411             },
 412
 413             sym::va_arg => match mk_va_list_ty(hir::Mutability::Mut) {
 414                 Some((va_list_ref_ty, _)) => (1, vec![va_list_ref_ty], param(0)),
 415                 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
 416             },
 417
 418             sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
 419
 420             sym::raw_eq => {
 421                 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
 422                 let param_ty =
 423                     tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
 424                 (1, vec![param_ty; 2], tcx.types.bool)
 425             }
 426
 427             sym::black_box => (1, vec![param(0)], param(0)),
 428
 429             sym::const_eval_select => (4, vec![param(0), param(1), param(2)], param(3)),
 430
 431             sym::vtable_size | sym::vtable_align => {
 432                 (0, vec![tcx.mk_imm_ptr(tcx.mk_unit())], tcx.types.usize)
 433             }
 434
 435             other => {
 436                 tcx.sess.emit_err(UnrecognizedIntrinsicFunction { span: it.span, name: other });
 437                 return;
 438             }
 439         };
 440         (n_tps, 0, inputs, output, unsafety)
 441     };
 442     let sig = tcx.mk_fn_sig(inputs.into_iter(), output, false, unsafety, Abi::RustIntrinsic);
 443     let sig = ty::Binder::bind_with_vars(sig, bound_vars);
 444     equate_intrinsic_type(tcx, it, n_tps, n_lts, sig)
 445 }
 446
 447 /// Type-check `extern "platform-intrinsic" { ... }` functions.
 448 pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
 449     let param = |n| {
 450         let name = Symbol::intern(&format!("P{}", n));
 451         tcx.mk_ty_param(n, name)
 452     };
 453
 454     let name = it.ident.name;
 455
 456     let (n_tps, inputs, output) = match name {
 457         sym::simd_eq | sym::simd_ne | sym::simd_lt | sym::simd_le | sym::simd_gt | sym::simd_ge => {
 458             (2, vec![param(0), param(0)], param(1))
 459         }
 460         sym::simd_add
 461         | sym::simd_sub
 462         | sym::simd_mul
 463         | sym::simd_rem
 464         | sym::simd_div
 465         | sym::simd_shl
 466         | sym::simd_shr
 467         | sym::simd_and
 468         | sym::simd_or
 469         | sym::simd_xor
 470         | sym::simd_fmin
 471         | sym::simd_fmax
 472         | sym::simd_fpow
 473         | sym::simd_saturating_add
 474         | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
 475         sym::simd_arith_offset => (2, vec![param(0), param(1)], param(0)),
 476         sym::simd_neg
 477         | sym::simd_fsqrt
 478         | sym::simd_fsin
 479         | sym::simd_fcos
 480         | sym::simd_fexp
 481         | sym::simd_fexp2
 482         | sym::simd_flog2
 483         | sym::simd_flog10
 484         | sym::simd_flog
 485         | sym::simd_fabs
 486         | sym::simd_ceil
 487         | sym::simd_floor
 488         | sym::simd_round
 489         | sym::simd_trunc => (1, vec![param(0)], param(0)),
 490         sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
 491         sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
 492         sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),
 493         sym::simd_scatter => (3, vec![param(0), param(1), param(2)], tcx.mk_unit()),
 494         sym::simd_insert => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
 495         sym::simd_extract => (2, vec![param(0), tcx.types.u32], param(1)),
 496         sym::simd_cast
 497         | sym::simd_as
 498         | sym::simd_cast_ptr
 499         | sym::simd_expose_addr
 500         | sym::simd_from_exposed_addr => (2, vec![param(0)], param(1)),
 501         sym::simd_bitmask => (2, vec![param(0)], param(1)),
 502         sym::simd_select | sym::simd_select_bitmask => {
 503             (2, vec![param(0), param(1), param(1)], param(1))
 504         }
 505         sym::simd_reduce_all | sym::simd_reduce_any => (1, vec![param(0)], tcx.types.bool),
 506         sym::simd_reduce_add_ordered | sym::simd_reduce_mul_ordered => {
 507             (2, vec![param(0), param(1)], param(1))
 508         }
 509         sym::simd_reduce_add_unordered
 510         | sym::simd_reduce_mul_unordered
 511         | sym::simd_reduce_and
 512         | sym::simd_reduce_or
 513         | sym::simd_reduce_xor
 514         | sym::simd_reduce_min
 515         | sym::simd_reduce_max
 516         | sym::simd_reduce_min_nanless
 517         | sym::simd_reduce_max_nanless => (2, vec![param(0)], param(1)),
 518         sym::simd_shuffle => (3, vec![param(0), param(0), param(1)], param(2)),
 519         name if name.as_str().starts_with("simd_shuffle") => {
 520             match name.as_str()["simd_shuffle".len()..].parse() {
 521                 Ok(n) => {
 522                     let params = vec![param(0), param(0), tcx.mk_array(tcx.types.u32, n)];
 523                     (2, params, param(1))
 524                 }
 525                 Err(_) => {
 526                     let msg =
 527                         format!("unrecognized platform-specific intrinsic function: `{name}`");
 528                     tcx.sess.struct_span_err(it.span, &msg).emit();
 529                     return;
 530                 }
 531             }
 532         }
 533         _ => {
 534             let msg = format!("unrecognized platform-specific intrinsic function: `{name}`");
 535             tcx.sess.struct_span_err(it.span, &msg).emit();
 536             return;
 537         }
 538     };
 539
 540     let sig = tcx.mk_fn_sig(
 541         inputs.into_iter(),
 542         output,
 543         false,
 544         hir::Unsafety::Unsafe,
 545         Abi::PlatformIntrinsic,
 546     );
 547     let sig = ty::Binder::dummy(sig);
 548     equate_intrinsic_type(tcx, it, n_tps, 0, sig)
 549 }