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