src/shims/intrinsics.rs

   1 use std::convert::TryInto;
   2 use std::iter;
   3
   4 use log::trace;
   5
   6 use rustc_apfloat::{Float, Round};
   7 use rustc_middle::ty::layout::{HasParamEnv, IntegerExt, LayoutOf};
   8 use rustc_middle::{mir, mir::BinOp, ty, ty::FloatTy};
   9 use rustc_target::abi::{Align, Endian, HasDataLayout, Integer, Size};
  10
  11 use crate::*;
  12 use helpers::check_arg_count;
  13
  14 pub enum AtomicOp {
  15     MirOp(mir::BinOp, bool),
  16     Max,
  17     Min,
  18 }
  19
  20 impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
  21 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
  22     fn call_intrinsic(
  23         &mut self,
  24         instance: ty::Instance<'tcx>,
  25         args: &[OpTy<'tcx, Tag>],
  26         ret: Option<(&PlaceTy<'tcx, Tag>, mir::BasicBlock)>,
  27         _unwind: StackPopUnwind,
  28     ) -> InterpResult<'tcx> {
  29         let this = self.eval_context_mut();
  30
  31         if this.emulate_intrinsic(instance, args, ret)? {
  32             return Ok(());
  33         }
  34
  35         // All supported intrinsics have a return place.
  36         let intrinsic_name = this.tcx.item_name(instance.def_id());
  37         let intrinsic_name = intrinsic_name.as_str();
  38         let (dest, ret) = match ret {
  39             None => throw_unsup_format!("unimplemented (diverging) intrinsic: {}", intrinsic_name),
  40             Some(p) => p,
  41         };
  42
  43         // Then handle terminating intrinsics.
  44         match intrinsic_name {
  45             // Miri overwriting CTFE intrinsics.
  46             "ptr_guaranteed_eq" => {
  47                 let &[ref left, ref right] = check_arg_count(args)?;
  48                 let left = this.read_immediate(left)?;
  49                 let right = this.read_immediate(right)?;
  50                 this.binop_ignore_overflow(mir::BinOp::Eq, &left, &right, dest)?;
  51             }
  52             "ptr_guaranteed_ne" => {
  53                 let &[ref left, ref right] = check_arg_count(args)?;
  54                 let left = this.read_immediate(left)?;
  55                 let right = this.read_immediate(right)?;
  56                 this.binop_ignore_overflow(mir::BinOp::Ne, &left, &right, dest)?;
  57             }
  58             "const_allocate" => {
  59                 // For now, for compatibility with the run-time implementation of this, we just return null.
  60                 // See <https://github.com/rust-lang/rust/issues/93935>.
  61                 this.write_null(dest)?;
  62             }
  63             "const_deallocate" => {
  64                 // complete NOP
  65             }
  66
  67             // Raw memory accesses
  68             "volatile_load" => {
  69                 let &[ref place] = check_arg_count(args)?;
  70                 let place = this.deref_operand(place)?;
  71                 this.copy_op(&place.into(), dest)?;
  72             }
  73             "volatile_store" => {
  74                 let &[ref place, ref dest] = check_arg_count(args)?;
  75                 let place = this.deref_operand(place)?;
  76                 this.copy_op(dest, &place.into())?;
  77             }
  78
  79             "write_bytes" | "volatile_set_memory" => {
  80                 let &[ref ptr, ref val_byte, ref count] = check_arg_count(args)?;
  81                 let ty = instance.substs.type_at(0);
  82                 let ty_layout = this.layout_of(ty)?;
  83                 let val_byte = this.read_scalar(val_byte)?.to_u8()?;
  84                 let ptr = this.read_pointer(ptr)?;
  85                 let count = this.read_scalar(count)?.to_machine_usize(this)?;
  86                 // `checked_mul` enforces a too small bound (the correct one would probably be machine_isize_max),
  87                 // but no actual allocation can be big enough for the difference to be noticeable.
  88                 let byte_count = ty_layout.size.checked_mul(count, this).ok_or_else(|| {
  89                     err_ub_format!("overflow computing total size of `{}`", intrinsic_name)
  90                 })?;
  91                 this.write_bytes_ptr(
  92                     ptr,
  93                     iter::repeat(val_byte).take(byte_count.bytes() as usize),
  94                 )?;
  95             }
  96
  97             // Floating-point operations
  98             "fabsf32" => {
  99                 let &[ref f] = check_arg_count(args)?;
 100                 let f = this.read_scalar(f)?.to_f32()?;
 101                 // Can be implemented in soft-floats.
 102                 this.write_scalar(Scalar::from_f32(f.abs()), dest)?;
 103             }
 104             "fabsf64" => {
 105                 let &[ref f] = check_arg_count(args)?;
 106                 let f = this.read_scalar(f)?.to_f64()?;
 107                 // Can be implemented in soft-floats.
 108                 this.write_scalar(Scalar::from_f64(f.abs()), dest)?;
 109             }
 110             #[rustfmt::skip]
 111             | "sinf32"
 112             | "cosf32"
 113             | "sqrtf32"
 114             | "expf32"
 115             | "exp2f32"
 116             | "logf32"
 117             | "log10f32"
 118             | "log2f32"
 119             | "floorf32"
 120             | "ceilf32"
 121             | "truncf32"
 122             | "roundf32"
 123             => {
 124                 let &[ref f] = check_arg_count(args)?;
 125                 // FIXME: Using host floats.
 126                 let f = f32::from_bits(this.read_scalar(f)?.to_u32()?);
 127                 let f = match intrinsic_name {
 128                     "sinf32" => f.sin(),
 129                     "cosf32" => f.cos(),
 130                     "sqrtf32" => f.sqrt(),
 131                     "expf32" => f.exp(),
 132                     "exp2f32" => f.exp2(),
 133                     "logf32" => f.ln(),
 134                     "log10f32" => f.log10(),
 135                     "log2f32" => f.log2(),
 136                     "floorf32" => f.floor(),
 137                     "ceilf32" => f.ceil(),
 138                     "truncf32" => f.trunc(),
 139                     "roundf32" => f.round(),
 140                     _ => bug!(),
 141                 };
 142                 this.write_scalar(Scalar::from_u32(f.to_bits()), dest)?;
 143             }
 144
 145             #[rustfmt::skip]
 146             | "sinf64"
 147             | "cosf64"
 148             | "sqrtf64"
 149             | "expf64"
 150             | "exp2f64"
 151             | "logf64"
 152             | "log10f64"
 153             | "log2f64"
 154             | "floorf64"
 155             | "ceilf64"
 156             | "truncf64"
 157             | "roundf64"
 158             => {
 159                 let &[ref f] = check_arg_count(args)?;
 160                 // FIXME: Using host floats.
 161                 let f = f64::from_bits(this.read_scalar(f)?.to_u64()?);
 162                 let f = match intrinsic_name {
 163                     "sinf64" => f.sin(),
 164                     "cosf64" => f.cos(),
 165                     "sqrtf64" => f.sqrt(),
 166                     "expf64" => f.exp(),
 167                     "exp2f64" => f.exp2(),
 168                     "logf64" => f.ln(),
 169                     "log10f64" => f.log10(),
 170                     "log2f64" => f.log2(),
 171                     "floorf64" => f.floor(),
 172                     "ceilf64" => f.ceil(),
 173                     "truncf64" => f.trunc(),
 174                     "roundf64" => f.round(),
 175                     _ => bug!(),
 176                 };
 177                 this.write_scalar(Scalar::from_u64(f.to_bits()), dest)?;
 178             }
 179
 180             #[rustfmt::skip]
 181             | "fadd_fast"
 182             | "fsub_fast"
 183             | "fmul_fast"
 184             | "fdiv_fast"
 185             | "frem_fast"
 186             => {
 187                 let &[ref a, ref b] = check_arg_count(args)?;
 188                 let a = this.read_immediate(a)?;
 189                 let b = this.read_immediate(b)?;
 190                 let op = match intrinsic_name {
 191                     "fadd_fast" => mir::BinOp::Add,
 192                     "fsub_fast" => mir::BinOp::Sub,
 193                     "fmul_fast" => mir::BinOp::Mul,
 194                     "fdiv_fast" => mir::BinOp::Div,
 195                     "frem_fast" => mir::BinOp::Rem,
 196                     _ => bug!(),
 197                 };
 198                 let float_finite = |x: ImmTy<'tcx, _>| -> InterpResult<'tcx, bool> {
 199                     Ok(match x.layout.ty.kind() {
 200                         ty::Float(FloatTy::F32) => x.to_scalar()?.to_f32()?.is_finite(),
 201                         ty::Float(FloatTy::F64) => x.to_scalar()?.to_f64()?.is_finite(),
 202                         _ => bug!(
 203                             "`{}` called with non-float input type {:?}",
 204                             intrinsic_name,
 205                             x.layout.ty
 206                         ),
 207                     })
 208                 };
 209                 match (float_finite(a)?, float_finite(b)?) {
 210                     (false, false) => throw_ub_format!(
 211                         "`{}` intrinsic called with non-finite value as both parameters",
 212                         intrinsic_name,
 213                     ),
 214                     (false, _) => throw_ub_format!(
 215                         "`{}` intrinsic called with non-finite value as first parameter",
 216                         intrinsic_name,
 217                     ),
 218                     (_, false) => throw_ub_format!(
 219                         "`{}` intrinsic called with non-finite value as second parameter",
 220                         intrinsic_name,
 221                     ),
 222                     _ => {}
 223                 }
 224                 this.binop_ignore_overflow(op, &a, &b, dest)?;
 225             }
 226
 227             #[rustfmt::skip]
 228             | "minnumf32"
 229             | "maxnumf32"
 230             | "copysignf32"
 231             => {
 232                 let &[ref a, ref b] = check_arg_count(args)?;
 233                 let a = this.read_scalar(a)?.to_f32()?;
 234                 let b = this.read_scalar(b)?.to_f32()?;
 235                 let res = match intrinsic_name {
 236                     "minnumf32" => a.min(b),
 237                     "maxnumf32" => a.max(b),
 238                     "copysignf32" => a.copy_sign(b),
 239                     _ => bug!(),
 240                 };
 241                 this.write_scalar(Scalar::from_f32(res), dest)?;
 242             }
 243
 244             #[rustfmt::skip]
 245             | "minnumf64"
 246             | "maxnumf64"
 247             | "copysignf64"
 248             => {
 249                 let &[ref a, ref b] = check_arg_count(args)?;
 250                 let a = this.read_scalar(a)?.to_f64()?;
 251                 let b = this.read_scalar(b)?.to_f64()?;
 252                 let res = match intrinsic_name {
 253                     "minnumf64" => a.min(b),
 254                     "maxnumf64" => a.max(b),
 255                     "copysignf64" => a.copy_sign(b),
 256                     _ => bug!(),
 257                 };
 258                 this.write_scalar(Scalar::from_f64(res), dest)?;
 259             }
 260
 261             "powf32" => {
 262                 let &[ref f, ref f2] = check_arg_count(args)?;
 263                 // FIXME: Using host floats.
 264                 let f = f32::from_bits(this.read_scalar(f)?.to_u32()?);
 265                 let f2 = f32::from_bits(this.read_scalar(f2)?.to_u32()?);
 266                 this.write_scalar(Scalar::from_u32(f.powf(f2).to_bits()), dest)?;
 267             }
 268
 269             "powf64" => {
 270                 let &[ref f, ref f2] = check_arg_count(args)?;
 271                 // FIXME: Using host floats.
 272                 let f = f64::from_bits(this.read_scalar(f)?.to_u64()?);
 273                 let f2 = f64::from_bits(this.read_scalar(f2)?.to_u64()?);
 274                 this.write_scalar(Scalar::from_u64(f.powf(f2).to_bits()), dest)?;
 275             }
 276
 277             "fmaf32" => {
 278                 let &[ref a, ref b, ref c] = check_arg_count(args)?;
 279                 let a = this.read_scalar(a)?.to_f32()?;
 280                 let b = this.read_scalar(b)?.to_f32()?;
 281                 let c = this.read_scalar(c)?.to_f32()?;
 282                 let res = a.mul_add(b, c).value;
 283                 this.write_scalar(Scalar::from_f32(res), dest)?;
 284             }
 285
 286             "fmaf64" => {
 287                 let &[ref a, ref b, ref c] = check_arg_count(args)?;
 288                 let a = this.read_scalar(a)?.to_f64()?;
 289                 let b = this.read_scalar(b)?.to_f64()?;
 290                 let c = this.read_scalar(c)?.to_f64()?;
 291                 let res = a.mul_add(b, c).value;
 292                 this.write_scalar(Scalar::from_f64(res), dest)?;
 293             }
 294
 295             "powif32" => {
 296                 let &[ref f, ref i] = check_arg_count(args)?;
 297                 // FIXME: Using host floats.
 298                 let f = f32::from_bits(this.read_scalar(f)?.to_u32()?);
 299                 let i = this.read_scalar(i)?.to_i32()?;
 300                 this.write_scalar(Scalar::from_u32(f.powi(i).to_bits()), dest)?;
 301             }
 302
 303             "powif64" => {
 304                 let &[ref f, ref i] = check_arg_count(args)?;
 305                 // FIXME: Using host floats.
 306                 let f = f64::from_bits(this.read_scalar(f)?.to_u64()?);
 307                 let i = this.read_scalar(i)?.to_i32()?;
 308                 this.write_scalar(Scalar::from_u64(f.powi(i).to_bits()), dest)?;
 309             }
 310
 311             "float_to_int_unchecked" => {
 312                 let &[ref val] = check_arg_count(args)?;
 313                 let val = this.read_immediate(val)?;
 314
 315                 let res = match val.layout.ty.kind() {
 316                     ty::Float(FloatTy::F32) =>
 317                         this.float_to_int_unchecked(val.to_scalar()?.to_f32()?, dest.layout.ty)?,
 318                     ty::Float(FloatTy::F64) =>
 319                         this.float_to_int_unchecked(val.to_scalar()?.to_f64()?, dest.layout.ty)?,
 320                     _ =>
 321                         bug!(
 322                             "`float_to_int_unchecked` called with non-float input type {:?}",
 323                             val.layout.ty
 324                         ),
 325                 };
 326
 327                 this.write_scalar(res, dest)?;
 328             }
 329
 330             // SIMD operations
 331             #[rustfmt::skip]
 332             | "simd_neg"
 333             | "simd_fabs"
 334             | "simd_ceil"
 335             | "simd_floor"
 336             | "simd_round"
 337             | "simd_trunc"
 338             | "simd_fsqrt" => {
 339                 let &[ref op] = check_arg_count(args)?;
 340                 let (op, op_len) = this.operand_to_simd(op)?;
 341                 let (dest, dest_len) = this.place_to_simd(dest)?;
 342
 343                 assert_eq!(dest_len, op_len);
 344
 345                 #[derive(Copy, Clone)]
 346                 enum HostFloatOp {
 347                     Ceil,
 348                     Floor,
 349                     Round,
 350                     Trunc,
 351                     Sqrt,
 352                 }
 353                 #[derive(Copy, Clone)]
 354                 enum Op {
 355                     MirOp(mir::UnOp),
 356                     Abs,
 357                     HostOp(HostFloatOp),
 358                 }
 359                 let which = match intrinsic_name {
 360                     "simd_neg" => Op::MirOp(mir::UnOp::Neg),
 361                     "simd_fabs" => Op::Abs,
 362                     "simd_ceil" => Op::HostOp(HostFloatOp::Ceil),
 363                     "simd_floor" => Op::HostOp(HostFloatOp::Floor),
 364                     "simd_round" => Op::HostOp(HostFloatOp::Round),
 365                     "simd_trunc" => Op::HostOp(HostFloatOp::Trunc),
 366                     "simd_fsqrt" => Op::HostOp(HostFloatOp::Sqrt),
 367                     _ => unreachable!(),
 368                 };
 369
 370                 for i in 0..dest_len {
 371                     let op = this.read_immediate(&this.mplace_index(&op, i)?.into())?;
 372                     let dest = this.mplace_index(&dest, i)?;
 373                     let val = match which {
 374                         Op::MirOp(mir_op) => this.unary_op(mir_op, &op)?.to_scalar()?,
 375                         Op::Abs => {
 376                             // Works for f32 and f64.
 377                             let ty::Float(float_ty) = op.layout.ty.kind() else {
 378                                 bug!("{} operand is not a float", intrinsic_name)
 379                             };
 380                             let op = op.to_scalar()?;
 381                             match float_ty {
 382                                 FloatTy::F32 => Scalar::from_f32(op.to_f32()?.abs()),
 383                                 FloatTy::F64 => Scalar::from_f64(op.to_f64()?.abs()),
 384                             }
 385                         }
 386                         Op::HostOp(host_op) => {
 387                             let ty::Float(float_ty) = op.layout.ty.kind() else {
 388                                 bug!("{} operand is not a float", intrinsic_name)
 389                             };
 390                             // FIXME using host floats
 391                             match float_ty {
 392                                 FloatTy::F32 => {
 393                                     let f = f32::from_bits(op.to_scalar()?.to_u32()?);
 394                                     let res = match host_op {
 395                                         HostFloatOp::Ceil => f.ceil(),
 396                                         HostFloatOp::Floor => f.floor(),
 397                                         HostFloatOp::Round => f.round(),
 398                                         HostFloatOp::Trunc => f.trunc(),
 399                                         HostFloatOp::Sqrt => f.sqrt(),
 400                                     };
 401                                     Scalar::from_u32(res.to_bits())
 402                                 }
 403                                 FloatTy::F64 => {
 404                                     let f = f64::from_bits(op.to_scalar()?.to_u64()?);
 405                                     let res = match host_op {
 406                                         HostFloatOp::Ceil => f.ceil(),
 407                                         HostFloatOp::Floor => f.floor(),
 408                                         HostFloatOp::Round => f.round(),
 409                                         HostFloatOp::Trunc => f.trunc(),
 410                                         HostFloatOp::Sqrt => f.sqrt(),
 411                                     };
 412                                     Scalar::from_u64(res.to_bits())
 413                                 }
 414                             }
 415
 416                         }
 417                     };
 418                     this.write_scalar(val, &dest.into())?;
 419                 }
 420             }
 421             #[rustfmt::skip]
 422             | "simd_add"
 423             | "simd_sub"
 424             | "simd_mul"
 425             | "simd_div"
 426             | "simd_rem"
 427             | "simd_shl"
 428             | "simd_shr"
 429             | "simd_and"
 430             | "simd_or"
 431             | "simd_xor"
 432             | "simd_eq"
 433             | "simd_ne"
 434             | "simd_lt"
 435             | "simd_le"
 436             | "simd_gt"
 437             | "simd_ge"
 438             | "simd_fmax"
 439             | "simd_fmin"
 440             | "simd_saturating_add"
 441             | "simd_saturating_sub" => {
 442                 use mir::BinOp;
 443
 444                 let &[ref left, ref right] = check_arg_count(args)?;
 445                 let (left, left_len) = this.operand_to_simd(left)?;
 446                 let (right, right_len) = this.operand_to_simd(right)?;
 447                 let (dest, dest_len) = this.place_to_simd(dest)?;
 448
 449                 assert_eq!(dest_len, left_len);
 450                 assert_eq!(dest_len, right_len);
 451
 452                 enum Op {
 453                     MirOp(BinOp),
 454                     SaturatingOp(BinOp),
 455                     FMax,
 456                     FMin,
 457                 }
 458                 let which = match intrinsic_name {
 459                     "simd_add" => Op::MirOp(BinOp::Add),
 460                     "simd_sub" => Op::MirOp(BinOp::Sub),
 461                     "simd_mul" => Op::MirOp(BinOp::Mul),
 462                     "simd_div" => Op::MirOp(BinOp::Div),
 463                     "simd_rem" => Op::MirOp(BinOp::Rem),
 464                     "simd_shl" => Op::MirOp(BinOp::Shl),
 465                     "simd_shr" => Op::MirOp(BinOp::Shr),
 466                     "simd_and" => Op::MirOp(BinOp::BitAnd),
 467                     "simd_or" => Op::MirOp(BinOp::BitOr),
 468                     "simd_xor" => Op::MirOp(BinOp::BitXor),
 469                     "simd_eq" => Op::MirOp(BinOp::Eq),
 470                     "simd_ne" => Op::MirOp(BinOp::Ne),
 471                     "simd_lt" => Op::MirOp(BinOp::Lt),
 472                     "simd_le" => Op::MirOp(BinOp::Le),
 473                     "simd_gt" => Op::MirOp(BinOp::Gt),
 474                     "simd_ge" => Op::MirOp(BinOp::Ge),
 475                     "simd_fmax" => Op::FMax,
 476                     "simd_fmin" => Op::FMin,
 477                     "simd_saturating_add" => Op::SaturatingOp(BinOp::Add),
 478                     "simd_saturating_sub" => Op::SaturatingOp(BinOp::Sub),
 479                     _ => unreachable!(),
 480                 };
 481
 482                 for i in 0..dest_len {
 483                     let left = this.read_immediate(&this.mplace_index(&left, i)?.into())?;
 484                     let right = this.read_immediate(&this.mplace_index(&right, i)?.into())?;
 485                     let dest = this.mplace_index(&dest, i)?;
 486                     let val = match which {
 487                         Op::MirOp(mir_op) => {
 488                             let (val, overflowed, ty) = this.overflowing_binary_op(mir_op, &left, &right)?;
 489                             if matches!(mir_op, BinOp::Shl | BinOp::Shr) {
 490                                 // Shifts have extra UB as SIMD operations that the MIR binop does not have.
 491                                 // See <https://github.com/rust-lang/rust/issues/91237>.
 492                                 if overflowed {
 493                                     let r_val = right.to_scalar()?.to_bits(right.layout.size)?;
 494                                     throw_ub_format!("overflowing shift by {} in `{}` in SIMD lane {}", r_val, intrinsic_name, i);
 495                                 }
 496                             }
 497                             if matches!(mir_op, BinOp::Eq | BinOp::Ne | BinOp::Lt | BinOp::Le | BinOp::Gt | BinOp::Ge) {
 498                                 // Special handling for boolean-returning operations
 499                                 assert_eq!(ty, this.tcx.types.bool);
 500                                 let val = val.to_bool().unwrap();
 501                                 bool_to_simd_element(val, dest.layout.size)
 502                             } else {
 503                                 assert_ne!(ty, this.tcx.types.bool);
 504                                 assert_eq!(ty, dest.layout.ty);
 505                                 val
 506                             }
 507                         }
 508                         Op::FMax => {
 509                             fmax_op(&left, &right)?
 510                         }
 511                         Op::FMin => {
 512                             fmin_op(&left, &right)?
 513                         }
 514                         Op::SaturatingOp(mir_op) => {
 515                             this.saturating_arith(mir_op, &left, &right)?
 516                         }
 517                     };
 518                     this.write_scalar(val, &dest.into())?;
 519                 }
 520             }
 521             "simd_fma" => {
 522                 let &[ref a, ref b, ref c] = check_arg_count(args)?;
 523                 let (a, a_len) = this.operand_to_simd(a)?;
 524                 let (b, b_len) = this.operand_to_simd(b)?;
 525                 let (c, c_len) = this.operand_to_simd(c)?;
 526                 let (dest, dest_len) = this.place_to_simd(dest)?;
 527
 528                 assert_eq!(dest_len, a_len);
 529                 assert_eq!(dest_len, b_len);
 530                 assert_eq!(dest_len, c_len);
 531
 532                 for i in 0..dest_len {
 533                     let a = this.read_immediate(&this.mplace_index(&a, i)?.into())?.to_scalar()?;
 534                     let b = this.read_immediate(&this.mplace_index(&b, i)?.into())?.to_scalar()?;
 535                     let c = this.read_immediate(&this.mplace_index(&c, i)?.into())?.to_scalar()?;
 536                     let dest = this.mplace_index(&dest, i)?;
 537
 538                     // Works for f32 and f64.
 539                     let ty::Float(float_ty) = dest.layout.ty.kind() else {
 540                         bug!("{} operand is not a float", intrinsic_name)
 541                     };
 542                     let val = match float_ty {
 543                         FloatTy::F32 =>
 544                             Scalar::from_f32(a.to_f32()?.mul_add(b.to_f32()?, c.to_f32()?).value),
 545                         FloatTy::F64 =>
 546                             Scalar::from_f64(a.to_f64()?.mul_add(b.to_f64()?, c.to_f64()?).value),
 547                     };
 548                     this.write_scalar(val, &dest.into())?;
 549                 }
 550             }
 551             #[rustfmt::skip]
 552             | "simd_reduce_and"
 553             | "simd_reduce_or"
 554             | "simd_reduce_xor"
 555             | "simd_reduce_any"
 556             | "simd_reduce_all"
 557             | "simd_reduce_max"
 558             | "simd_reduce_min" => {
 559                 use mir::BinOp;
 560
 561                 let &[ref op] = check_arg_count(args)?;
 562                 let (op, op_len) = this.operand_to_simd(op)?;
 563
 564                 let imm_from_bool =
 565                     |b| ImmTy::from_scalar(Scalar::from_bool(b), this.machine.layouts.bool);
 566
 567                 enum Op {
 568                     MirOp(BinOp),
 569                     MirOpBool(BinOp),
 570                     Max,
 571                     Min,
 572                 }
 573                 let which = match intrinsic_name {
 574                     "simd_reduce_and" => Op::MirOp(BinOp::BitAnd),
 575                     "simd_reduce_or" => Op::MirOp(BinOp::BitOr),
 576                     "simd_reduce_xor" => Op::MirOp(BinOp::BitXor),
 577                     "simd_reduce_any" => Op::MirOpBool(BinOp::BitOr),
 578                     "simd_reduce_all" => Op::MirOpBool(BinOp::BitAnd),
 579                     "simd_reduce_max" => Op::Max,
 580                     "simd_reduce_min" => Op::Min,
 581                     _ => unreachable!(),
 582                 };
 583
 584                 // Initialize with first lane, then proceed with the rest.
 585                 let mut res = this.read_immediate(&this.mplace_index(&op, 0)?.into())?;
 586                 if matches!(which, Op::MirOpBool(_)) {
 587                     // Convert to `bool` scalar.
 588                     res = imm_from_bool(simd_element_to_bool(res)?);
 589                 }
 590                 for i in 1..op_len {
 591                     let op = this.read_immediate(&this.mplace_index(&op, i)?.into())?;
 592                     res = match which {
 593                         Op::MirOp(mir_op) => {
 594                             this.binary_op(mir_op, &res, &op)?
 595                         }
 596                         Op::MirOpBool(mir_op) => {
 597                             let op = imm_from_bool(simd_element_to_bool(op)?);
 598                             this.binary_op(mir_op, &res, &op)?
 599                         }
 600                         Op::Max => {
 601                             if matches!(res.layout.ty.kind(), ty::Float(_)) {
 602                                 ImmTy::from_scalar(fmax_op(&res, &op)?, res.layout)
 603                             } else {
 604                                 // Just boring integers, so NaNs to worry about
 605                                 if this.binary_op(BinOp::Ge, &res, &op)?.to_scalar()?.to_bool()? {
 606                                     res
 607                                 } else {
 608                                     op
 609                                 }
 610                             }
 611                         }
 612                         Op::Min => {
 613                             if matches!(res.layout.ty.kind(), ty::Float(_)) {
 614                                 ImmTy::from_scalar(fmin_op(&res, &op)?, res.layout)
 615                             } else {
 616                                 // Just boring integers, so NaNs to worry about
 617                                 if this.binary_op(BinOp::Le, &res, &op)?.to_scalar()?.to_bool()? {
 618                                     res
 619                                 } else {
 620                                     op
 621                                 }
 622                             }
 623                         }
 624                     };
 625                 }
 626                 this.write_immediate(*res, dest)?;
 627             }
 628             #[rustfmt::skip]
 629             | "simd_reduce_add_ordered"
 630             | "simd_reduce_mul_ordered" => {
 631                 use mir::BinOp;
 632
 633                 let &[ref op, ref init] = check_arg_count(args)?;
 634                 let (op, op_len) = this.operand_to_simd(op)?;
 635                 let init = this.read_immediate(init)?;
 636
 637                 let mir_op = match intrinsic_name {
 638                     "simd_reduce_add_ordered" => BinOp::Add,
 639                     "simd_reduce_mul_ordered" => BinOp::Mul,
 640                     _ => unreachable!(),
 641                 };
 642
 643                 let mut res = init;
 644                 for i in 0..op_len {
 645                     let op = this.read_immediate(&this.mplace_index(&op, i)?.into())?;
 646                     res = this.binary_op(mir_op, &res, &op)?;
 647                 }
 648                 this.write_immediate(*res, dest)?;
 649             }
 650             "simd_select" => {
 651                 let &[ref mask, ref yes, ref no] = check_arg_count(args)?;
 652                 let (mask, mask_len) = this.operand_to_simd(mask)?;
 653                 let (yes, yes_len) = this.operand_to_simd(yes)?;
 654                 let (no, no_len) = this.operand_to_simd(no)?;
 655                 let (dest, dest_len) = this.place_to_simd(dest)?;
 656
 657                 assert_eq!(dest_len, mask_len);
 658                 assert_eq!(dest_len, yes_len);
 659                 assert_eq!(dest_len, no_len);
 660
 661                 for i in 0..dest_len {
 662                     let mask = this.read_immediate(&this.mplace_index(&mask, i)?.into())?;
 663                     let yes = this.read_immediate(&this.mplace_index(&yes, i)?.into())?;
 664                     let no = this.read_immediate(&this.mplace_index(&no, i)?.into())?;
 665                     let dest = this.mplace_index(&dest, i)?;
 666
 667                     let val = if simd_element_to_bool(mask)? { yes } else { no };
 668                     this.write_immediate(*val, &dest.into())?;
 669                 }
 670             }
 671             "simd_select_bitmask" => {
 672                 let &[ref mask, ref yes, ref no] = check_arg_count(args)?;
 673                 let (yes, yes_len) = this.operand_to_simd(yes)?;
 674                 let (no, no_len) = this.operand_to_simd(no)?;
 675                 let (dest, dest_len) = this.place_to_simd(dest)?;
 676                 let bitmask_len = dest_len.max(8);
 677
 678                 assert!(mask.layout.ty.is_integral());
 679                 assert!(bitmask_len <= 64);
 680                 assert_eq!(bitmask_len, mask.layout.size.bits());
 681                 assert_eq!(dest_len, yes_len);
 682                 assert_eq!(dest_len, no_len);
 683
 684                 let mask: u64 = this
 685                     .read_scalar(mask)?
 686                     .check_init()?
 687                     .to_bits(mask.layout.size)?
 688                     .try_into()
 689                     .unwrap();
 690                 for i in 0..dest_len {
 691                     let mask =
 692                         mask & (1 << simd_bitmask_index(i, dest_len, this.data_layout().endian));
 693                     let yes = this.read_immediate(&this.mplace_index(&yes, i)?.into())?;
 694                     let no = this.read_immediate(&this.mplace_index(&no, i)?.into())?;
 695                     let dest = this.mplace_index(&dest, i)?;
 696
 697                     let val = if mask != 0 { yes } else { no };
 698                     this.write_immediate(*val, &dest.into())?;
 699                 }
 700                 for i in dest_len..bitmask_len {
 701                     // If the mask is "padded", ensure that padding is all-zero.
 702                     let mask = mask & (1 << i);
 703                     if mask != 0 {
 704                         throw_ub_format!(
 705                             "a SIMD bitmask less than 8 bits long must be filled with 0s for the remaining bits"
 706                         );
 707                     }
 708                 }
 709             }
 710             #[rustfmt::skip]
 711             "simd_cast" | "simd_as" => {
 712                 let &[ref op] = check_arg_count(args)?;
 713                 let (op, op_len) = this.operand_to_simd(op)?;
 714                 let (dest, dest_len) = this.place_to_simd(dest)?;
 715
 716                 assert_eq!(dest_len, op_len);
 717
 718                 let safe_cast = intrinsic_name == "simd_as";
 719
 720                 for i in 0..dest_len {
 721                     let op = this.read_immediate(&this.mplace_index(&op, i)?.into())?;
 722                     let dest = this.mplace_index(&dest, i)?;
 723
 724                     let val = match (op.layout.ty.kind(), dest.layout.ty.kind()) {
 725                         // Int-to-(int|float): always safe
 726                         (ty::Int(_) | ty::Uint(_), ty::Int(_) | ty::Uint(_) | ty::Float(_)) =>
 727                             this.misc_cast(&op, dest.layout.ty)?,
 728                         // Float-to-float: always safe
 729                         (ty::Float(_), ty::Float(_)) =>
 730                             this.misc_cast(&op, dest.layout.ty)?,
 731                         // Float-to-int in safe mode
 732                         (ty::Float(_), ty::Int(_) | ty::Uint(_)) if safe_cast =>
 733                             this.misc_cast(&op, dest.layout.ty)?,
 734                         // Float-to-int in unchecked mode
 735                         (ty::Float(FloatTy::F32), ty::Int(_) | ty::Uint(_)) if !safe_cast =>
 736                             this.float_to_int_unchecked(op.to_scalar()?.to_f32()?, dest.layout.ty)?.into(),
 737                         (ty::Float(FloatTy::F64), ty::Int(_) | ty::Uint(_)) if !safe_cast =>
 738                             this.float_to_int_unchecked(op.to_scalar()?.to_f64()?, dest.layout.ty)?.into(),
 739                         _ =>
 740                             throw_unsup_format!(
 741                                 "Unsupported SIMD cast from element type {} to {}",
 742                                 op.layout.ty,
 743                                 dest.layout.ty
 744                             ),
 745                     };
 746                     this.write_immediate(val, &dest.into())?;
 747                 }
 748             }
 749             "simd_shuffle" => {
 750                 let &[ref left, ref right, ref index] = check_arg_count(args)?;
 751                 let (left, left_len) = this.operand_to_simd(left)?;
 752                 let (right, right_len) = this.operand_to_simd(right)?;
 753                 let (dest, dest_len) = this.place_to_simd(dest)?;
 754
 755                 // `index` is an array, not a SIMD type
 756                 let ty::Array(_, index_len) = index.layout.ty.kind() else {
 757                     bug!("simd_shuffle index argument has non-array type {}", index.layout.ty)
 758                 };
 759                 let index_len = index_len.eval_usize(*this.tcx, this.param_env());
 760
 761                 assert_eq!(left_len, right_len);
 762                 assert_eq!(index_len, dest_len);
 763
 764                 for i in 0..dest_len {
 765                     let src_index: u64 = this
 766                         .read_immediate(&this.operand_index(&index, i)?.into())?
 767                         .to_scalar()?
 768                         .to_u32()?
 769                         .into();
 770                     let dest = this.mplace_index(&dest, i)?;
 771
 772                     let val = if src_index < left_len {
 773                         this.read_immediate(&this.mplace_index(&left, src_index)?.into())?
 774                     } else if src_index < left_len.checked_add(right_len).unwrap() {
 775                         this.read_immediate(
 776                             &this.mplace_index(&right, src_index - left_len)?.into(),
 777                         )?
 778                     } else {
 779                         bug!(
 780                             "simd_shuffle index {} is out of bounds for 2 vectors of size {}",
 781                             src_index,
 782                             left_len
 783                         );
 784                     };
 785                     this.write_immediate(*val, &dest.into())?;
 786                 }
 787             }
 788             "simd_gather" => {
 789                 let &[ref passthru, ref ptrs, ref mask] = check_arg_count(args)?;
 790                 let (passthru, passthru_len) = this.operand_to_simd(passthru)?;
 791                 let (ptrs, ptrs_len) = this.operand_to_simd(ptrs)?;
 792                 let (mask, mask_len) = this.operand_to_simd(mask)?;
 793                 let (dest, dest_len) = this.place_to_simd(dest)?;
 794
 795                 assert_eq!(dest_len, passthru_len);
 796                 assert_eq!(dest_len, ptrs_len);
 797                 assert_eq!(dest_len, mask_len);
 798
 799                 for i in 0..dest_len {
 800                     let passthru = this.read_immediate(&this.mplace_index(&passthru, i)?.into())?;
 801                     let ptr = this.read_immediate(&this.mplace_index(&ptrs, i)?.into())?;
 802                     let mask = this.read_immediate(&this.mplace_index(&mask, i)?.into())?;
 803                     let dest = this.mplace_index(&dest, i)?;
 804
 805                     let val = if simd_element_to_bool(mask)? {
 806                         let place = this.deref_operand(&ptr.into())?;
 807                         this.read_immediate(&place.into())?
 808                     } else {
 809                         passthru
 810                     };
 811                     this.write_immediate(*val, &dest.into())?;
 812                 }
 813             }
 814             "simd_scatter" => {
 815                 let &[ref value, ref ptrs, ref mask] = check_arg_count(args)?;
 816                 let (value, value_len) = this.operand_to_simd(value)?;
 817                 let (ptrs, ptrs_len) = this.operand_to_simd(ptrs)?;
 818                 let (mask, mask_len) = this.operand_to_simd(mask)?;
 819
 820                 assert_eq!(ptrs_len, value_len);
 821                 assert_eq!(ptrs_len, mask_len);
 822
 823                 for i in 0..ptrs_len {
 824                     let value = this.read_immediate(&this.mplace_index(&value, i)?.into())?;
 825                     let ptr = this.read_immediate(&this.mplace_index(&ptrs, i)?.into())?;
 826                     let mask = this.read_immediate(&this.mplace_index(&mask, i)?.into())?;
 827
 828                     if simd_element_to_bool(mask)? {
 829                         let place = this.deref_operand(&ptr.into())?;
 830                         this.write_immediate(*value, &place.into())?;
 831                     }
 832                 }
 833             }
 834             "simd_bitmask" => {
 835                 let &[ref op] = check_arg_count(args)?;
 836                 let (op, op_len) = this.operand_to_simd(op)?;
 837                 let bitmask_len = op_len.max(8);
 838
 839                 assert!(dest.layout.ty.is_integral());
 840                 assert!(bitmask_len <= 64);
 841                 assert_eq!(bitmask_len, dest.layout.size.bits());
 842
 843                 let mut res = 0u64;
 844                 for i in 0..op_len {
 845                     let op = this.read_immediate(&this.mplace_index(&op, i)?.into())?;
 846                     if simd_element_to_bool(op)? {
 847                         res |= 1 << simd_bitmask_index(i, op_len, this.data_layout().endian);
 848                     }
 849                 }
 850                 this.write_int(res, dest)?;
 851             }
 852
 853             // Atomic operations
 854             "atomic_load" => this.atomic_load(args, dest, AtomicReadOp::SeqCst)?,
 855             "atomic_load_relaxed" => this.atomic_load(args, dest, AtomicReadOp::Relaxed)?,
 856             "atomic_load_acq" => this.atomic_load(args, dest, AtomicReadOp::Acquire)?,
 857
 858             "atomic_store" => this.atomic_store(args, AtomicWriteOp::SeqCst)?,
 859             "atomic_store_relaxed" => this.atomic_store(args, AtomicWriteOp::Relaxed)?,
 860             "atomic_store_rel" => this.atomic_store(args, AtomicWriteOp::Release)?,
 861
 862             "atomic_fence_acq" => this.atomic_fence(args, AtomicFenceOp::Acquire)?,
 863             "atomic_fence_rel" => this.atomic_fence(args, AtomicFenceOp::Release)?,
 864             "atomic_fence_acqrel" => this.atomic_fence(args, AtomicFenceOp::AcqRel)?,
 865             "atomic_fence" => this.atomic_fence(args, AtomicFenceOp::SeqCst)?,
 866
 867             "atomic_singlethreadfence_acq" => this.compiler_fence(args, AtomicFenceOp::Acquire)?,
 868             "atomic_singlethreadfence_rel" => this.compiler_fence(args, AtomicFenceOp::Release)?,
 869             "atomic_singlethreadfence_acqrel" =>
 870                 this.compiler_fence(args, AtomicFenceOp::AcqRel)?,
 871             "atomic_singlethreadfence" => this.compiler_fence(args, AtomicFenceOp::SeqCst)?,
 872
 873             "atomic_xchg" => this.atomic_exchange(args, dest, AtomicRwOp::SeqCst)?,
 874             "atomic_xchg_acq" => this.atomic_exchange(args, dest, AtomicRwOp::Acquire)?,
 875             "atomic_xchg_rel" => this.atomic_exchange(args, dest, AtomicRwOp::Release)?,
 876             "atomic_xchg_acqrel" => this.atomic_exchange(args, dest, AtomicRwOp::AcqRel)?,
 877             "atomic_xchg_relaxed" => this.atomic_exchange(args, dest, AtomicRwOp::Relaxed)?,
 878
 879             #[rustfmt::skip]
 880             "atomic_cxchg" =>
 881                 this.atomic_compare_exchange(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::SeqCst)?,
 882             #[rustfmt::skip]
 883             "atomic_cxchg_acq" =>
 884                 this.atomic_compare_exchange(args, dest, AtomicRwOp::Acquire, AtomicReadOp::Acquire)?,
 885             #[rustfmt::skip]
 886             "atomic_cxchg_rel" =>
 887                 this.atomic_compare_exchange(args, dest, AtomicRwOp::Release, AtomicReadOp::Relaxed)?,
 888             #[rustfmt::skip]
 889             "atomic_cxchg_acqrel" =>
 890                 this.atomic_compare_exchange(args, dest, AtomicRwOp::AcqRel, AtomicReadOp::Acquire)?,
 891             #[rustfmt::skip]
 892             "atomic_cxchg_relaxed" =>
 893                 this.atomic_compare_exchange(args, dest, AtomicRwOp::Relaxed, AtomicReadOp::Relaxed)?,
 894             #[rustfmt::skip]
 895             "atomic_cxchg_acq_failrelaxed" =>
 896                 this.atomic_compare_exchange(args, dest, AtomicRwOp::Acquire, AtomicReadOp::Relaxed)?,
 897             #[rustfmt::skip]
 898             "atomic_cxchg_acqrel_failrelaxed" =>
 899                 this.atomic_compare_exchange(args, dest, AtomicRwOp::AcqRel, AtomicReadOp::Relaxed)?,
 900             #[rustfmt::skip]
 901             "atomic_cxchg_failrelaxed" =>
 902                 this.atomic_compare_exchange(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::Relaxed)?,
 903             #[rustfmt::skip]
 904             "atomic_cxchg_failacq" =>
 905                 this.atomic_compare_exchange(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::Acquire)?,
 906
 907             #[rustfmt::skip]
 908             "atomic_cxchgweak" =>
 909                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::SeqCst)?,
 910             #[rustfmt::skip]
 911             "atomic_cxchgweak_acq" =>
 912                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::Acquire, AtomicReadOp::Acquire)?,
 913             #[rustfmt::skip]
 914             "atomic_cxchgweak_rel" =>
 915                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::Release, AtomicReadOp::Relaxed)?,
 916             #[rustfmt::skip]
 917             "atomic_cxchgweak_acqrel" =>
 918                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::AcqRel, AtomicReadOp::Acquire)?,
 919             #[rustfmt::skip]
 920             "atomic_cxchgweak_relaxed" =>
 921                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::Relaxed, AtomicReadOp::Relaxed)?,
 922             #[rustfmt::skip]
 923             "atomic_cxchgweak_acq_failrelaxed" =>
 924                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::Acquire, AtomicReadOp::Relaxed)?,
 925             #[rustfmt::skip]
 926             "atomic_cxchgweak_acqrel_failrelaxed" =>
 927                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::AcqRel, AtomicReadOp::Relaxed)?,
 928             #[rustfmt::skip]
 929             "atomic_cxchgweak_failrelaxed" =>
 930                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::Relaxed)?,
 931             #[rustfmt::skip]
 932             "atomic_cxchgweak_failacq" =>
 933                 this.atomic_compare_exchange_weak(args, dest, AtomicRwOp::SeqCst, AtomicReadOp::Acquire)?,
 934
 935             #[rustfmt::skip]
 936             "atomic_or" =>
 937                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitOr, false), AtomicRwOp::SeqCst)?,
 938             #[rustfmt::skip]
 939             "atomic_or_acq" =>
 940                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitOr, false), AtomicRwOp::Acquire)?,
 941             #[rustfmt::skip]
 942             "atomic_or_rel" =>
 943                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitOr, false), AtomicRwOp::Release)?,
 944             #[rustfmt::skip]
 945             "atomic_or_acqrel" =>
 946                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitOr, false), AtomicRwOp::AcqRel)?,
 947             #[rustfmt::skip]
 948             "atomic_or_relaxed" =>
 949                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitOr, false), AtomicRwOp::Relaxed)?,
 950             #[rustfmt::skip]
 951             "atomic_xor" =>
 952                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitXor, false), AtomicRwOp::SeqCst)?,
 953             #[rustfmt::skip]
 954             "atomic_xor_acq" =>
 955                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitXor, false), AtomicRwOp::Acquire)?,
 956             #[rustfmt::skip]
 957             "atomic_xor_rel" =>
 958                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitXor, false), AtomicRwOp::Release)?,
 959             #[rustfmt::skip]
 960             "atomic_xor_acqrel" =>
 961                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitXor, false), AtomicRwOp::AcqRel)?,
 962             #[rustfmt::skip]
 963             "atomic_xor_relaxed" =>
 964                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitXor, false), AtomicRwOp::Relaxed)?,
 965             #[rustfmt::skip]
 966             "atomic_and" =>
 967                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, false), AtomicRwOp::SeqCst)?,
 968             #[rustfmt::skip]
 969             "atomic_and_acq" =>
 970                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, false), AtomicRwOp::Acquire)?,
 971             #[rustfmt::skip]
 972             "atomic_and_rel" =>
 973                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, false), AtomicRwOp::Release)?,
 974             #[rustfmt::skip]
 975             "atomic_and_acqrel" =>
 976                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, false), AtomicRwOp::AcqRel)?,
 977             #[rustfmt::skip]
 978             "atomic_and_relaxed" =>
 979                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, false), AtomicRwOp::Relaxed)?,
 980             #[rustfmt::skip]
 981             "atomic_nand" =>
 982                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, true), AtomicRwOp::SeqCst)?,
 983             #[rustfmt::skip]
 984             "atomic_nand_acq" =>
 985                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, true), AtomicRwOp::Acquire)?,
 986             #[rustfmt::skip]
 987             "atomic_nand_rel" =>
 988                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, true), AtomicRwOp::Release)?,
 989             #[rustfmt::skip]
 990             "atomic_nand_acqrel" =>
 991                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, true), AtomicRwOp::AcqRel)?,
 992             #[rustfmt::skip]
 993             "atomic_nand_relaxed" =>
 994                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::BitAnd, true), AtomicRwOp::Relaxed)?,
 995             #[rustfmt::skip]
 996             "atomic_xadd" =>
 997                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Add, false), AtomicRwOp::SeqCst)?,
 998             #[rustfmt::skip]
 999             "atomic_xadd_acq" =>
1000                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Add, false), AtomicRwOp::Acquire)?,
1001             #[rustfmt::skip]
1002             "atomic_xadd_rel" =>
1003                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Add, false), AtomicRwOp::Release)?,
1004             #[rustfmt::skip]
1005             "atomic_xadd_acqrel" =>
1006                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Add, false), AtomicRwOp::AcqRel)?,
1007             #[rustfmt::skip]
1008             "atomic_xadd_relaxed" =>
1009                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Add, false), AtomicRwOp::Relaxed)?,
1010             #[rustfmt::skip]
1011             "atomic_xsub" =>
1012                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Sub, false), AtomicRwOp::SeqCst)?,
1013             #[rustfmt::skip]
1014             "atomic_xsub_acq" =>
1015                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Sub, false), AtomicRwOp::Acquire)?,
1016             #[rustfmt::skip]
1017             "atomic_xsub_rel" =>
1018                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Sub, false), AtomicRwOp::Release)?,
1019             #[rustfmt::skip]
1020             "atomic_xsub_acqrel" =>
1021                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Sub, false), AtomicRwOp::AcqRel)?,
1022             #[rustfmt::skip]
1023             "atomic_xsub_relaxed" =>
1024                 this.atomic_op(args, dest, AtomicOp::MirOp(BinOp::Sub, false), AtomicRwOp::Relaxed)?,
1025             "atomic_min" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::SeqCst)?,
1026             "atomic_min_acq" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Acquire)?,
1027             "atomic_min_rel" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Release)?,
1028             "atomic_min_acqrel" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::AcqRel)?,
1029             "atomic_min_relaxed" =>
1030                 this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Relaxed)?,
1031             "atomic_max" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::SeqCst)?,
1032             "atomic_max_acq" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Acquire)?,
1033             "atomic_max_rel" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Release)?,
1034             "atomic_max_acqrel" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::AcqRel)?,
1035             "atomic_max_relaxed" =>
1036                 this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Relaxed)?,
1037             "atomic_umin" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::SeqCst)?,
1038             "atomic_umin_acq" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Acquire)?,
1039             "atomic_umin_rel" => this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Release)?,
1040             "atomic_umin_acqrel" =>
1041                 this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::AcqRel)?,
1042             "atomic_umin_relaxed" =>
1043                 this.atomic_op(args, dest, AtomicOp::Min, AtomicRwOp::Relaxed)?,
1044             "atomic_umax" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::SeqCst)?,
1045             "atomic_umax_acq" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Acquire)?,
1046             "atomic_umax_rel" => this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Release)?,
1047             "atomic_umax_acqrel" =>
1048                 this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::AcqRel)?,
1049             "atomic_umax_relaxed" =>
1050                 this.atomic_op(args, dest, AtomicOp::Max, AtomicRwOp::Relaxed)?,
1051
1052             // Other
1053             "exact_div" => {
1054                 let &[ref num, ref denom] = check_arg_count(args)?;
1055                 this.exact_div(&this.read_immediate(num)?, &this.read_immediate(denom)?, dest)?;
1056             }
1057
1058             "try" => return this.handle_try(args, dest, ret),
1059
1060             "breakpoint" => {
1061                 let &[] = check_arg_count(args)?;
1062                 // normally this would raise a SIGTRAP, which aborts if no debugger is connected
1063                 throw_machine_stop!(TerminationInfo::Abort("Trace/breakpoint trap".to_string()))
1064             }
1065
1066             name => throw_unsup_format!("unimplemented intrinsic: {}", name),
1067         }
1068
1069         trace!("{:?}", this.dump_place(**dest));
1070         this.go_to_block(ret);
1071         Ok(())
1072     }
1073
1074     fn atomic_load(
1075         &mut self,
1076         args: &[OpTy<'tcx, Tag>],
1077         dest: &PlaceTy<'tcx, Tag>,
1078         atomic: AtomicReadOp,
1079     ) -> InterpResult<'tcx> {
1080         let this = self.eval_context_mut();
1081
1082         let &[ref place] = check_arg_count(args)?;
1083         let place = this.deref_operand(place)?;
1084
1085         // make sure it fits into a scalar; otherwise it cannot be atomic
1086         let val = this.read_scalar_atomic(&place, atomic)?;
1087
1088         // Check alignment requirements. Atomics must always be aligned to their size,
1089         // even if the type they wrap would be less aligned (e.g. AtomicU64 on 32bit must
1090         // be 8-aligned).
1091         let align = Align::from_bytes(place.layout.size.bytes()).unwrap();
1092         this.check_ptr_access_align(
1093             place.ptr,
1094             place.layout.size,
1095             align,
1096             CheckInAllocMsg::MemoryAccessTest,
1097         )?;
1098         // Perform regular access.
1099         this.write_scalar(val, dest)?;
1100         Ok(())
1101     }
1102
1103     fn atomic_store(
1104         &mut self,
1105         args: &[OpTy<'tcx, Tag>],
1106         atomic: AtomicWriteOp,
1107     ) -> InterpResult<'tcx> {
1108         let this = self.eval_context_mut();
1109
1110         let &[ref place, ref val] = check_arg_count(args)?;
1111         let place = this.deref_operand(place)?;
1112         let val = this.read_scalar(val)?; // make sure it fits into a scalar; otherwise it cannot be atomic
1113
1114         // Check alignment requirements. Atomics must always be aligned to their size,
1115         // even if the type they wrap would be less aligned (e.g. AtomicU64 on 32bit must
1116         // be 8-aligned).
1117         let align = Align::from_bytes(place.layout.size.bytes()).unwrap();
1118         this.check_ptr_access_align(
1119             place.ptr,
1120             place.layout.size,
1121             align,
1122             CheckInAllocMsg::MemoryAccessTest,
1123         )?;
1124
1125         // Perform atomic store
1126         this.write_scalar_atomic(val, &place, atomic)?;
1127         Ok(())
1128     }
1129
1130     fn compiler_fence(
1131         &mut self,
1132         args: &[OpTy<'tcx, Tag>],
1133         atomic: AtomicFenceOp,
1134     ) -> InterpResult<'tcx> {
1135         let &[] = check_arg_count(args)?;
1136         let _ = atomic;
1137         //FIXME: compiler fences are currently ignored
1138         Ok(())
1139     }
1140
1141     fn atomic_fence(
1142         &mut self,
1143         args: &[OpTy<'tcx, Tag>],
1144         atomic: AtomicFenceOp,
1145     ) -> InterpResult<'tcx> {
1146         let this = self.eval_context_mut();
1147         let &[] = check_arg_count(args)?;
1148         this.validate_atomic_fence(atomic)?;
1149         Ok(())
1150     }
1151
1152     fn atomic_op(
1153         &mut self,
1154         args: &[OpTy<'tcx, Tag>],
1155         dest: &PlaceTy<'tcx, Tag>,
1156         atomic_op: AtomicOp,
1157         atomic: AtomicRwOp,
1158     ) -> InterpResult<'tcx> {
1159         let this = self.eval_context_mut();
1160
1161         let &[ref place, ref rhs] = check_arg_count(args)?;
1162         let place = this.deref_operand(place)?;
1163
1164         if !place.layout.ty.is_integral() {
1165             bug!("Atomic arithmetic operations only work on integer types");
1166         }
1167         let rhs = this.read_immediate(rhs)?;
1168
1169         // Check alignment requirements. Atomics must always be aligned to their size,
1170         // even if the type they wrap would be less aligned (e.g. AtomicU64 on 32bit must
1171         // be 8-aligned).
1172         let align = Align::from_bytes(place.layout.size.bytes()).unwrap();
1173         this.check_ptr_access_align(
1174             place.ptr,
1175             place.layout.size,
1176             align,
1177             CheckInAllocMsg::MemoryAccessTest,
1178         )?;
1179
1180         match atomic_op {
1181             AtomicOp::Min => {
1182                 let old = this.atomic_min_max_scalar(&place, rhs, true, atomic)?;
1183                 this.write_immediate(*old, &dest)?; // old value is returned
1184                 Ok(())
1185             }
1186             AtomicOp::Max => {
1187                 let old = this.atomic_min_max_scalar(&place, rhs, false, atomic)?;
1188                 this.write_immediate(*old, &dest)?; // old value is returned
1189                 Ok(())
1190             }
1191             AtomicOp::MirOp(op, neg) => {
1192                 let old = this.atomic_op_immediate(&place, &rhs, op, neg, atomic)?;
1193                 this.write_immediate(*old, dest)?; // old value is returned
1194                 Ok(())
1195             }
1196         }
1197     }
1198
1199     fn atomic_exchange(
1200         &mut self,
1201         args: &[OpTy<'tcx, Tag>],
1202         dest: &PlaceTy<'tcx, Tag>,
1203         atomic: AtomicRwOp,
1204     ) -> InterpResult<'tcx> {
1205         let this = self.eval_context_mut();
1206
1207         let &[ref place, ref new] = check_arg_count(args)?;
1208         let place = this.deref_operand(place)?;
1209         let new = this.read_scalar(new)?;
1210
1211         // Check alignment requirements. Atomics must always be aligned to their size,
1212         // even if the type they wrap would be less aligned (e.g. AtomicU64 on 32bit must
1213         // be 8-aligned).
1214         let align = Align::from_bytes(place.layout.size.bytes()).unwrap();
1215         this.check_ptr_access_align(
1216             place.ptr,
1217             place.layout.size,
1218             align,
1219             CheckInAllocMsg::MemoryAccessTest,
1220         )?;
1221
1222         let old = this.atomic_exchange_scalar(&place, new, atomic)?;
1223         this.write_scalar(old, dest)?; // old value is returned
1224         Ok(())
1225     }
1226
1227     fn atomic_compare_exchange_impl(
1228         &mut self,
1229         args: &[OpTy<'tcx, Tag>],
1230         dest: &PlaceTy<'tcx, Tag>,
1231         success: AtomicRwOp,
1232         fail: AtomicReadOp,
1233         can_fail_spuriously: bool,
1234     ) -> InterpResult<'tcx> {
1235         let this = self.eval_context_mut();
1236
1237         let &[ref place, ref expect_old, ref new] = check_arg_count(args)?;
1238         let place = this.deref_operand(place)?;
1239         let expect_old = this.read_immediate(expect_old)?; // read as immediate for the sake of `binary_op()`
1240         let new = this.read_scalar(new)?;
1241
1242         // Check alignment requirements. Atomics must always be aligned to their size,
1243         // even if the type they wrap would be less aligned (e.g. AtomicU64 on 32bit must
1244         // be 8-aligned).
1245         let align = Align::from_bytes(place.layout.size.bytes()).unwrap();
1246         this.check_ptr_access_align(
1247             place.ptr,
1248             place.layout.size,
1249             align,
1250             CheckInAllocMsg::MemoryAccessTest,
1251         )?;
1252
1253         let old = this.atomic_compare_exchange_scalar(
1254             &place,
1255             &expect_old,
1256             new,
1257             success,
1258             fail,
1259             can_fail_spuriously,
1260         )?;
1261
1262         // Return old value.
1263         this.write_immediate(old, dest)?;
1264         Ok(())
1265     }
1266
1267     fn atomic_compare_exchange(
1268         &mut self,
1269         args: &[OpTy<'tcx, Tag>],
1270         dest: &PlaceTy<'tcx, Tag>,
1271         success: AtomicRwOp,
1272         fail: AtomicReadOp,
1273     ) -> InterpResult<'tcx> {
1274         self.atomic_compare_exchange_impl(args, dest, success, fail, false)
1275     }
1276
1277     fn atomic_compare_exchange_weak(
1278         &mut self,
1279         args: &[OpTy<'tcx, Tag>],
1280         dest: &PlaceTy<'tcx, Tag>,
1281         success: AtomicRwOp,
1282         fail: AtomicReadOp,
1283     ) -> InterpResult<'tcx> {
1284         self.atomic_compare_exchange_impl(args, dest, success, fail, true)
1285     }
1286
1287     fn float_to_int_unchecked<F>(
1288         &self,
1289         f: F,
1290         dest_ty: ty::Ty<'tcx>,
1291     ) -> InterpResult<'tcx, Scalar<Tag>>
1292     where
1293         F: Float + Into<Scalar<Tag>>,
1294     {
1295         let this = self.eval_context_ref();
1296
1297         // Step 1: cut off the fractional part of `f`. The result of this is
1298         // guaranteed to be precisely representable in IEEE floats.
1299         let f = f.round_to_integral(Round::TowardZero).value;
1300
1301         // Step 2: Cast the truncated float to the target integer type and see if we lose any information in this step.
1302         Ok(match dest_ty.kind() {
1303             // Unsigned
1304             ty::Uint(t) => {
1305                 let size = Integer::from_uint_ty(this, *t).size();
1306                 let res = f.to_u128(size.bits_usize());
1307                 if res.status.is_empty() {
1308                     // No status flags means there was no further rounding or other loss of precision.
1309                     Scalar::from_uint(res.value, size)
1310                 } else {
1311                     // `f` was not representable in this integer type.
1312                     throw_ub_format!(
1313                         "`float_to_int_unchecked` intrinsic called on {} which cannot be represented in target type `{:?}`",
1314                         f,
1315                         dest_ty,
1316                     );
1317                 }
1318             }
1319             // Signed
1320             ty::Int(t) => {
1321                 let size = Integer::from_int_ty(this, *t).size();
1322                 let res = f.to_i128(size.bits_usize());
1323                 if res.status.is_empty() {
1324                     // No status flags means there was no further rounding or other loss of precision.
1325                     Scalar::from_int(res.value, size)
1326                 } else {
1327                     // `f` was not representable in this integer type.
1328                     throw_ub_format!(
1329                         "`float_to_int_unchecked` intrinsic called on {} which cannot be represented in target type `{:?}`",
1330                         f,
1331                         dest_ty,
1332                     );
1333                 }
1334             }
1335             // Nothing else
1336             _ => bug!("`float_to_int_unchecked` called with non-int output type {:?}", dest_ty),
1337         })
1338     }
1339 }
1340
1341 fn fmax_op<'tcx>(
1342     left: &ImmTy<'tcx, Tag>,
1343     right: &ImmTy<'tcx, Tag>,
1344 ) -> InterpResult<'tcx, Scalar<Tag>> {
1345     assert_eq!(left.layout.ty, right.layout.ty);
1346     let ty::Float(float_ty) = left.layout.ty.kind() else {
1347         bug!("fmax operand is not a float")
1348     };
1349     let left = left.to_scalar()?;
1350     let right = right.to_scalar()?;
1351     Ok(match float_ty {
1352         FloatTy::F32 => Scalar::from_f32(left.to_f32()?.max(right.to_f32()?)),
1353         FloatTy::F64 => Scalar::from_f64(left.to_f64()?.max(right.to_f64()?)),
1354     })
1355 }
1356
1357 fn fmin_op<'tcx>(
1358     left: &ImmTy<'tcx, Tag>,
1359     right: &ImmTy<'tcx, Tag>,
1360 ) -> InterpResult<'tcx, Scalar<Tag>> {
1361     assert_eq!(left.layout.ty, right.layout.ty);
1362     let ty::Float(float_ty) = left.layout.ty.kind() else {
1363         bug!("fmin operand is not a float")
1364     };
1365     let left = left.to_scalar()?;
1366     let right = right.to_scalar()?;
1367     Ok(match float_ty {
1368         FloatTy::F32 => Scalar::from_f32(left.to_f32()?.min(right.to_f32()?)),
1369         FloatTy::F64 => Scalar::from_f64(left.to_f64()?.min(right.to_f64()?)),
1370     })
1371 }
1372
1373 fn bool_to_simd_element(b: bool, size: Size) -> Scalar<Tag> {
1374     // SIMD uses all-1 as pattern for "true"
1375     let val = if b { -1 } else { 0 };
1376     Scalar::from_int(val, size)
1377 }
1378
1379 fn simd_element_to_bool<'tcx>(elem: ImmTy<'tcx, Tag>) -> InterpResult<'tcx, bool> {
1380     let val = elem.to_scalar()?.to_int(elem.layout.size)?;
1381     Ok(match val {
1382         0 => false,
1383         -1 => true,
1384         _ => throw_ub_format!("each element of a SIMD mask must be all-0-bits or all-1-bits"),
1385     })
1386 }
1387
1388 fn simd_bitmask_index(idx: u64, vec_len: u64, endianess: Endian) -> u64 {
1389     assert!(idx < vec_len);
1390     match endianess {
1391         Endian::Little => idx,
1392         Endian::Big => vec_len - 1 - idx, // reverse order of bits
1393     }
1394 }