src/intrinsics.rs

   1 use crate::prelude::*;
   2
   3 use rustc::ty::subst::SubstsRef;
   4
   5 macro_rules! intrinsic_pat {
   6     (_) => {
   7         _
   8     };
   9     ($name:ident) => {
  10         stringify!($name)
  11     }
  12 }
  13
  14 macro_rules! intrinsic_arg {
  15     (c $fx:expr, $arg:ident) => {
  16         $arg
  17     };
  18     (v $fx:expr, $arg:ident) => {
  19         $arg.load_scalar($fx)
  20     };
  21 }
  22
  23 macro_rules! intrinsic_substs {
  24     ($substs:expr, $index:expr,) => {};
  25     ($substs:expr, $index:expr, $first:ident $(,$rest:ident)*) => {
  26         let $first = $substs.type_at($index);
  27         intrinsic_substs!($substs, $index+1, $($rest),*);
  28     };
  29 }
  30
  31 macro_rules! intrinsic_match {
  32     ($fx:expr, $intrinsic:expr, $substs:expr, $args:expr, $(
  33         $($name:tt)|+ $(if $cond:expr)?, $(<$($subst:ident),*>)? ($($a:ident $arg:ident),*) $content:block;
  34     )*) => {
  35         match $intrinsic {
  36             $(
  37                 $(intrinsic_pat!($name))|* $(if $cond)? => {
  38                     #[allow(unused_parens, non_snake_case)]
  39                     {
  40                         $(
  41                             intrinsic_substs!($substs, 0, $($subst),*);
  42                         )?
  43                         if let [$($arg),*] = *$args {
  44                             let ($($arg),*) = (
  45                                 $(intrinsic_arg!($a $fx, $arg)),*
  46                             );
  47                             #[warn(unused_parens, non_snake_case)]
  48                             {
  49                                 $content
  50                             }
  51                         } else {
  52                             bug!("wrong number of args for intrinsic {:?}", $intrinsic);
  53                         }
  54                     }
  55                 }
  56             )*
  57             _ => unimpl!("unsupported intrinsic {}", $intrinsic),
  58         }
  59     };
  60 }
  61
  62 macro_rules! atomic_binop_return_old {
  63     ($fx:expr, $op:ident<$T:ident>($ptr:ident, $src:ident) -> $ret:ident) => {
  64         let clif_ty = $fx.clif_type($T).unwrap();
  65         let old = $fx.bcx.ins().load(clif_ty, MemFlags::new(), $ptr, 0);
  66         let new = $fx.bcx.ins().$op(old, $src);
  67         $fx.bcx.ins().store(MemFlags::new(), new, $ptr, 0);
  68         $ret.write_cvalue($fx, CValue::by_val(old, $fx.layout_of($T)));
  69     };
  70 }
  71
  72 macro_rules! atomic_minmax {
  73     ($fx:expr, $cc:expr, <$T:ident> ($ptr:ident, $src:ident) -> $ret:ident) => {
  74         // Read old
  75         let clif_ty = $fx.clif_type($T).unwrap();
  76         let old = $fx.bcx.ins().load(clif_ty, MemFlags::new(), $ptr, 0);
  77
  78         // Compare
  79         let is_eq = $fx.bcx.ins().icmp(IntCC::SignedGreaterThan, old, $src);
  80         let new = crate::common::codegen_select(&mut $fx.bcx, is_eq, old, $src);
  81
  82         // Write new
  83         $fx.bcx.ins().store(MemFlags::new(), new, $ptr, 0);
  84
  85         let ret_val = CValue::by_val(old, $ret.layout());
  86         $ret.write_cvalue($fx, ret_val);
  87     };
  88 }
  89
  90 pub fn codegen_intrinsic_call<'a, 'tcx: 'a>(
  91     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
  92     def_id: DefId,
  93     substs: SubstsRef<'tcx>,
  94     args: Vec<CValue<'tcx>>,
  95     destination: Option<(CPlace<'tcx>, BasicBlock)>,
  96 ) {
  97     let intrinsic = fx.tcx.item_name(def_id).as_str();
  98     let intrinsic = &intrinsic[..];
  99
 100     let ret = match destination {
 101         Some((place, _)) => place,
 102         None => {
 103             // Insert non returning intrinsics here
 104             match intrinsic {
 105                 "abort" => {
 106                     trap_panic(fx, "Called intrinsic::abort.");
 107                 }
 108                 "unreachable" => {
 109                     trap_unreachable(fx, "[corruption] Called intrinsic::unreachable.");
 110                 }
 111                 _ => unimplemented!("unsupported instrinsic {}", intrinsic),
 112             }
 113             return;
 114         }
 115     };
 116
 117     let u64_layout = fx.layout_of(fx.tcx.types.u64);
 118     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 119
 120     intrinsic_match! {
 121         fx, intrinsic, substs, args,
 122
 123         assume, (c _a) {};
 124         likely | unlikely, (c a) {
 125             ret.write_cvalue(fx, a);
 126         };
 127         breakpoint, () {
 128             fx.bcx.ins().debugtrap();
 129         };
 130         copy | copy_nonoverlapping, <elem_ty> (v src, v dst, v count) {
 131             let elem_size: u64 = fx.layout_of(elem_ty).size.bytes();
 132             let elem_size = fx
 133                 .bcx
 134                 .ins()
 135                 .iconst(fx.pointer_type, elem_size as i64);
 136             assert_eq!(args.len(), 3);
 137             let byte_amount = fx.bcx.ins().imul(count, elem_size);
 138
 139             if intrinsic.ends_with("_nonoverlapping") {
 140                 fx.bcx.call_memcpy(fx.module.target_config(), dst, src, byte_amount);
 141             } else {
 142                 fx.bcx.call_memmove(fx.module.target_config(), dst, src, byte_amount);
 143             }
 144         };
 145         discriminant_value, (c val) {
 146             let pointee_layout = fx.layout_of(val.layout().ty.builtin_deref(true).unwrap().ty);
 147             let place = CPlace::for_addr(val.load_scalar(fx), pointee_layout);
 148             let discr = crate::base::trans_get_discriminant(fx, place, ret.layout());
 149             ret.write_cvalue(fx, discr);
 150         };
 151         size_of, <T> () {
 152             let size_of = fx.layout_of(T).size.bytes();
 153             let size_of = CValue::const_val(fx, usize_layout.ty, size_of as i64);
 154             ret.write_cvalue(fx, size_of);
 155         };
 156         size_of_val, <T> (c ptr) {
 157             let layout = fx.layout_of(T);
 158             let size = if layout.is_unsized() {
 159                 let (_ptr, info) = ptr.load_scalar_pair(fx);
 160                 let (size, _align) = crate::unsize::size_and_align_of_dst(fx, layout.ty, info);
 161                 size
 162             } else {
 163                 fx
 164                     .bcx
 165                     .ins()
 166                     .iconst(fx.pointer_type, layout.size.bytes() as i64)
 167             };
 168             ret.write_cvalue(fx, CValue::by_val(size, usize_layout));
 169         };
 170         min_align_of, <T> () {
 171             let min_align = fx.layout_of(T).align.abi.bytes();
 172             let min_align = CValue::const_val(fx, usize_layout.ty, min_align as i64);
 173             ret.write_cvalue(fx, min_align);
 174         };
 175         min_align_of_val, <T> (c ptr) {
 176             let layout = fx.layout_of(T);
 177             let align = if layout.is_unsized() {
 178                 let (_ptr, info) = ptr.load_scalar_pair(fx);
 179                 let (_size, align) = crate::unsize::size_and_align_of_dst(fx, layout.ty, info);
 180                 align
 181             } else {
 182                 fx
 183                     .bcx
 184                     .ins()
 185                     .iconst(fx.pointer_type, layout.align.abi.bytes() as i64)
 186             };
 187             ret.write_cvalue(fx, CValue::by_val(align, usize_layout));
 188         };
 189         pref_align_of, <T> () {
 190             let pref_align = fx.layout_of(T).align.pref.bytes();
 191             let pref_align = CValue::const_val(fx, usize_layout.ty, pref_align as i64);
 192             ret.write_cvalue(fx, pref_align);
 193         };
 194
 195
 196         type_id, <T> () {
 197             let type_id = fx.tcx.type_id_hash(T);
 198             let type_id = CValue::const_val(fx, u64_layout.ty, type_id as i64);
 199             ret.write_cvalue(fx, type_id);
 200         };
 201         type_name, <T> () {
 202             let type_name = fx.tcx.type_name(T);
 203             let type_name = crate::constant::trans_const_value(fx, type_name);
 204             ret.write_cvalue(fx, type_name);
 205         };
 206
 207         _ if intrinsic.starts_with("unchecked_") || intrinsic == "exact_div", (c x, c y) {
 208             // FIXME trap on overflow
 209             let bin_op = match intrinsic {
 210                 "unchecked_sub" => BinOp::Sub,
 211                 "unchecked_div" | "exact_div" => BinOp::Div,
 212                 "unchecked_rem" => BinOp::Rem,
 213                 "unchecked_shl" => BinOp::Shl,
 214                 "unchecked_shr" => BinOp::Shr,
 215                 _ => unimplemented!("intrinsic {}", intrinsic),
 216             };
 217             let res = match ret.layout().ty.sty {
 218                 ty::Uint(_) => crate::base::trans_int_binop(
 219                     fx,
 220                     bin_op,
 221                     x,
 222                     y,
 223                     ret.layout().ty,
 224                     false,
 225                 ),
 226                 ty::Int(_) => crate::base::trans_int_binop(
 227                     fx,
 228                     bin_op,
 229                     x,
 230                     y,
 231                     ret.layout().ty,
 232                     true,
 233                 ),
 234                 _ => panic!(),
 235             };
 236             ret.write_cvalue(fx, res);
 237         };
 238         _ if intrinsic.ends_with("_with_overflow"), <T> (c x, c y) {
 239             assert_eq!(x.layout().ty, y.layout().ty);
 240             let bin_op = match intrinsic {
 241                 "add_with_overflow" => BinOp::Add,
 242                 "sub_with_overflow" => BinOp::Sub,
 243                 "mul_with_overflow" => BinOp::Mul,
 244                 _ => unimplemented!("intrinsic {}", intrinsic),
 245             };
 246             let res = match T.sty {
 247                 ty::Uint(_) => crate::base::trans_checked_int_binop(
 248                     fx,
 249                     bin_op,
 250                     x,
 251                     y,
 252                     ret.layout().ty,
 253                     false,
 254                 ),
 255                 ty::Int(_) => crate::base::trans_checked_int_binop(
 256                     fx,
 257                     bin_op,
 258                     x,
 259                     y,
 260                     ret.layout().ty,
 261                     true,
 262                 ),
 263                 _ => panic!(),
 264             };
 265             ret.write_cvalue(fx, res);
 266         };
 267         _ if intrinsic.starts_with("overflowing_"), <T> (c x, c y) {
 268             assert_eq!(x.layout().ty, y.layout().ty);
 269             let bin_op = match intrinsic {
 270                 "overflowing_add" => BinOp::Add,
 271                 "overflowing_sub" => BinOp::Sub,
 272                 "overflowing_mul" => BinOp::Mul,
 273                 _ => unimplemented!("intrinsic {}", intrinsic),
 274             };
 275             let res = match T.sty {
 276                 ty::Uint(_) => crate::base::trans_int_binop(
 277                     fx,
 278                     bin_op,
 279                     x,
 280                     y,
 281                     ret.layout().ty,
 282                     false,
 283                 ),
 284                 ty::Int(_) => crate::base::trans_int_binop(
 285                     fx,
 286                     bin_op,
 287                     x,
 288                     y,
 289                     ret.layout().ty,
 290                     true,
 291                 ),
 292                 _ => panic!(),
 293             };
 294             ret.write_cvalue(fx, res);
 295         };
 296         _ if intrinsic.starts_with("saturating_"), <T> (c x, c y) {
 297             // FIXME implement saturating behavior
 298             assert_eq!(x.layout().ty, y.layout().ty);
 299             let bin_op = match intrinsic {
 300                 "saturating_add" => BinOp::Add,
 301                 "saturating_sub" => BinOp::Sub,
 302                 "saturating_mul" => BinOp::Mul,
 303                 _ => unimplemented!("intrinsic {}", intrinsic),
 304             };
 305             let res = match T.sty {
 306                 ty::Uint(_) => crate::base::trans_int_binop(
 307                     fx,
 308                     bin_op,
 309                     x,
 310                     y,
 311                     ret.layout().ty,
 312                     false,
 313                 ),
 314                 ty::Int(_) => crate::base::trans_int_binop(
 315                     fx,
 316                     bin_op,
 317                     x,
 318                     y,
 319                     ret.layout().ty,
 320                     true,
 321                 ),
 322                 _ => panic!(),
 323             };
 324             ret.write_cvalue(fx, res);
 325         };
 326         rotate_left, <T>(v x, v y) {
 327             let layout = fx.layout_of(T);
 328             let res = fx.bcx.ins().rotl(x, y);
 329             ret.write_cvalue(fx, CValue::by_val(res, layout));
 330         };
 331         rotate_right, <T>(v x, v y) {
 332             let layout = fx.layout_of(T);
 333             let res = fx.bcx.ins().rotr(x, y);
 334             ret.write_cvalue(fx, CValue::by_val(res, layout));
 335         };
 336
 337         // The only difference between offset and arith_offset is regarding UB. Because Cranelift
 338         // doesn't have UB both are codegen'ed the same way
 339         offset | arith_offset, (c base, v offset) {
 340             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
 341             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
 342             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
 343             let base_val = base.load_scalar(fx);
 344             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
 345             ret.write_cvalue(fx, CValue::by_val(res, args[0].layout()));
 346         };
 347
 348         transmute, <src_ty, dst_ty> (c from) {
 349             assert_eq!(from.layout().ty, src_ty);
 350             let addr = from.force_stack(fx);
 351             let dst_layout = fx.layout_of(dst_ty);
 352             ret.write_cvalue(fx, CValue::by_ref(addr, dst_layout))
 353         };
 354         init, () {
 355             if ret.layout().abi == Abi::Uninhabited {
 356                 crate::trap::trap_panic(fx, "[panic] Called intrinsic::init for uninhabited type.");
 357                 return;
 358             }
 359
 360             match ret {
 361                 CPlace::NoPlace(_layout) => {}
 362                 CPlace::Var(var, layout) => {
 363                     let clif_ty = fx.clif_type(layout.ty).unwrap();
 364                     let val = match clif_ty {
 365                         types::I8 | types::I16 | types::I32 | types::I64 => fx.bcx.ins().iconst(clif_ty, 0),
 366                         types::F32 => {
 367                             let zero = fx.bcx.ins().iconst(types::I32, 0);
 368                             fx.bcx.ins().bitcast(types::F32, zero)
 369                         }
 370                         types::F64 => {
 371                             let zero = fx.bcx.ins().iconst(types::I64, 0);
 372                             fx.bcx.ins().bitcast(types::F64, zero)
 373                         }
 374                         _ => panic!("clif_type returned {}", clif_ty),
 375                     };
 376                     fx.bcx.def_var(mir_var(var), val);
 377                 }
 378                 _ => {
 379                     let addr = ret.to_addr(fx);
 380                     let layout = ret.layout();
 381                     fx.bcx.emit_small_memset(fx.module.target_config(), addr, 0, layout.size.bytes(), 1);
 382                 }
 383             }
 384         };
 385         write_bytes, (c dst, v val, v count) {
 386             let pointee_ty = dst.layout().ty.builtin_deref(true).unwrap().ty;
 387             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
 388             let count = fx.bcx.ins().imul_imm(count, pointee_size as i64);
 389             let dst_ptr = dst.load_scalar(fx);
 390             fx.bcx.call_memset(fx.module.target_config(), dst_ptr, val, count);
 391         };
 392         ctlz | ctlz_nonzero, <T> (v arg) {
 393             let res = if T == fx.tcx.types.u128 || T == fx.tcx.types.i128 {
 394                 // FIXME verify this algorithm is correct
 395                 let (lsb, msb) = fx.bcx.ins().isplit(arg);
 396                 let lsb_lz = fx.bcx.ins().clz(lsb);
 397                 let msb_lz = fx.bcx.ins().clz(msb);
 398                 let msb_lz_is_64 = fx.bcx.ins().icmp_imm(IntCC::Equal, msb_lz, 64);
 399                 let lsb_lz_plus_64 = fx.bcx.ins().iadd_imm(lsb_lz, 64);
 400                 fx.bcx.ins().select(msb_lz_is_64, lsb_lz_plus_64, msb_lz)
 401             } else {
 402                 fx.bcx.ins().clz(arg)
 403             };
 404             let res = CValue::by_val(res, fx.layout_of(T));
 405             ret.write_cvalue(fx, res);
 406         };
 407         cttz | cttz_nonzero, <T> (v arg) {
 408             let res = if T == fx.tcx.types.u128 || T == fx.tcx.types.i128 {
 409                 // FIXME verify this algorithm is correct
 410                 let (lsb, msb) = fx.bcx.ins().isplit(arg);
 411                 let lsb_tz = fx.bcx.ins().ctz(lsb);
 412                 let msb_tz = fx.bcx.ins().ctz(msb);
 413                 let lsb_tz_is_64 = fx.bcx.ins().icmp_imm(IntCC::Equal, lsb_tz, 64);
 414                 let msb_lz_plus_64 = fx.bcx.ins().iadd_imm(msb_tz, 64);
 415                 fx.bcx.ins().select(lsb_tz_is_64, msb_lz_plus_64, lsb_tz)
 416             } else {
 417                 fx.bcx.ins().ctz(arg)
 418             };
 419             let res = CValue::by_val(res, fx.layout_of(T));
 420             ret.write_cvalue(fx, res);
 421         };
 422         ctpop, <T> (v arg) {
 423             let res = CValue::by_val(fx.bcx.ins().popcnt(arg), fx.layout_of(T));
 424             ret.write_cvalue(fx, res);
 425         };
 426         bitreverse, <T> (v arg) {
 427             let res = CValue::by_val(fx.bcx.ins().bitrev(arg), fx.layout_of(T));
 428             ret.write_cvalue(fx, res);
 429         };
 430         bswap, <T> (v arg) {
 431             // FIXME(CraneStation/cranelift#794) add bswap instruction to cranelift
 432             fn swap(bcx: &mut FunctionBuilder, v: Value) -> Value {
 433                 match bcx.func.dfg.value_type(v) {
 434                     types::I8 => v,
 435
 436                     // https://code.woboq.org/gcc/include/bits/byteswap.h.html
 437                     types::I16 => {
 438                         let tmp1 = bcx.ins().ishl_imm(v, 8);
 439                         let n1 = bcx.ins().band_imm(tmp1, 0xFF00);
 440
 441                         let tmp2 = bcx.ins().ushr_imm(v, 8);
 442                         let n2 = bcx.ins().band_imm(tmp2, 0x00FF);
 443
 444                         bcx.ins().bor(n1, n2)
 445                     }
 446                     types::I32 => {
 447                         let tmp1 = bcx.ins().ishl_imm(v, 24);
 448                         let n1 = bcx.ins().band_imm(tmp1, 0xFF00_0000);
 449
 450                         let tmp2 = bcx.ins().ishl_imm(v, 8);
 451                         let n2 = bcx.ins().band_imm(tmp2, 0x00FF_0000);
 452
 453                         let tmp3 = bcx.ins().ushr_imm(v, 8);
 454                         let n3 = bcx.ins().band_imm(tmp3, 0x0000_FF00);
 455
 456                         let tmp4 = bcx.ins().ushr_imm(v, 24);
 457                         let n4 = bcx.ins().band_imm(tmp4, 0x0000_00FF);
 458
 459                         let or_tmp1 = bcx.ins().bor(n1, n2);
 460                         let or_tmp2 = bcx.ins().bor(n3, n4);
 461                         bcx.ins().bor(or_tmp1, or_tmp2)
 462                     }
 463                     types::I64 => {
 464                         let tmp1 = bcx.ins().ishl_imm(v, 56);
 465                         let n1 = bcx.ins().band_imm(tmp1, 0xFF00_0000_0000_0000u64 as i64);
 466
 467                         let tmp2 = bcx.ins().ishl_imm(v, 40);
 468                         let n2 = bcx.ins().band_imm(tmp2, 0x00FF_0000_0000_0000u64 as i64);
 469
 470                         let tmp3 = bcx.ins().ishl_imm(v, 24);
 471                         let n3 = bcx.ins().band_imm(tmp3, 0x0000_FF00_0000_0000u64 as i64);
 472
 473                         let tmp4 = bcx.ins().ishl_imm(v, 8);
 474                         let n4 = bcx.ins().band_imm(tmp4, 0x0000_00FF_0000_0000u64 as i64);
 475
 476                         let tmp5 = bcx.ins().ushr_imm(v, 8);
 477                         let n5 = bcx.ins().band_imm(tmp5, 0x0000_0000_FF00_0000u64 as i64);
 478
 479                         let tmp6 = bcx.ins().ushr_imm(v, 24);
 480                         let n6 = bcx.ins().band_imm(tmp6, 0x0000_0000_00FF_0000u64 as i64);
 481
 482                         let tmp7 = bcx.ins().ushr_imm(v, 40);
 483                         let n7 = bcx.ins().band_imm(tmp7, 0x0000_0000_0000_FF00u64 as i64);
 484
 485                         let tmp8 = bcx.ins().ushr_imm(v, 56);
 486                         let n8 = bcx.ins().band_imm(tmp8, 0x0000_0000_0000_00FFu64 as i64);
 487
 488                         let or_tmp1 = bcx.ins().bor(n1, n2);
 489                         let or_tmp2 = bcx.ins().bor(n3, n4);
 490                         let or_tmp3 = bcx.ins().bor(n5, n6);
 491                         let or_tmp4 = bcx.ins().bor(n7, n8);
 492
 493                         let or_tmp5 = bcx.ins().bor(or_tmp1, or_tmp2);
 494                         let or_tmp6 = bcx.ins().bor(or_tmp3, or_tmp4);
 495                         bcx.ins().bor(or_tmp5, or_tmp6)
 496                     }
 497                     ty => unimplemented!("bwap {}", ty),
 498                 }
 499             };
 500             let res = CValue::by_val(swap(&mut fx.bcx, arg), fx.layout_of(T));
 501             ret.write_cvalue(fx, res);
 502         };
 503         needs_drop, <T> () {
 504             let needs_drop = if T.needs_drop(fx.tcx, ParamEnv::reveal_all()) {
 505                 1
 506             } else {
 507                 0
 508             };
 509             let needs_drop = CValue::const_val(fx, fx.tcx.types.bool, needs_drop);
 510             ret.write_cvalue(fx, needs_drop);
 511         };
 512         panic_if_uninhabited, <T> () {
 513             if fx.layout_of(T).abi.is_uninhabited() {
 514                 crate::trap::trap_panic(fx, "[panic] Called intrinsic::panic_if_uninhabited for uninhabited type.");
 515                 return;
 516             }
 517         };
 518
 519         volatile_load, (c ptr) {
 520             // Cranelift treats loads as volatile by default
 521             let inner_layout =
 522                 fx.layout_of(ptr.layout().ty.builtin_deref(true).unwrap().ty);
 523             let val = CValue::by_ref(ptr.load_scalar(fx), inner_layout);
 524             ret.write_cvalue(fx, val);
 525         };
 526         volatile_store, (v ptr, c val) {
 527             // Cranelift treats stores as volatile by default
 528             let dest = CPlace::for_addr(ptr, val.layout());
 529             dest.write_cvalue(fx, val);
 530         };
 531
 532         _ if intrinsic.starts_with("atomic_fence"), () {};
 533         _ if intrinsic.starts_with("atomic_singlethreadfence"), () {};
 534         _ if intrinsic.starts_with("atomic_load"), (c ptr) {
 535             let inner_layout =
 536                 fx.layout_of(ptr.layout().ty.builtin_deref(true).unwrap().ty);
 537             let val = CValue::by_ref(ptr.load_scalar(fx), inner_layout);
 538             ret.write_cvalue(fx, val);
 539         };
 540         _ if intrinsic.starts_with("atomic_store"), (v ptr, c val) {
 541             let dest = CPlace::for_addr(ptr, val.layout());
 542             dest.write_cvalue(fx, val);
 543         };
 544         _ if intrinsic.starts_with("atomic_xchg"), <T> (v ptr, c src) {
 545             // Read old
 546             let clif_ty = fx.clif_type(T).unwrap();
 547             let old = fx.bcx.ins().load(clif_ty, MemFlags::new(), ptr, 0);
 548             ret.write_cvalue(fx, CValue::by_val(old, fx.layout_of(T)));
 549
 550             // Write new
 551             let dest = CPlace::for_addr(ptr, src.layout());
 552             dest.write_cvalue(fx, src);
 553         };
 554         _ if intrinsic.starts_with("atomic_cxchg"), <T> (v ptr, v test_old, v new) { // both atomic_cxchg_* and atomic_cxchgweak_*
 555             // Read old
 556             let clif_ty = fx.clif_type(T).unwrap();
 557             let old = fx.bcx.ins().load(clif_ty, MemFlags::new(), ptr, 0);
 558
 559             // Compare
 560             let is_eq = fx.bcx.ins().icmp(IntCC::Equal, old, test_old);
 561             let new = crate::common::codegen_select(&mut fx.bcx, is_eq, new, old); // Keep old if not equal to test_old
 562
 563             // Write new
 564             fx.bcx.ins().store(MemFlags::new(), new, ptr, 0);
 565
 566             let ret_val = CValue::by_val_pair(old, fx.bcx.ins().bint(types::I8, is_eq), ret.layout());
 567             ret.write_cvalue(fx, ret_val);
 568         };
 569
 570         _ if intrinsic.starts_with("atomic_xadd"), <T> (v ptr, v amount) {
 571             atomic_binop_return_old! (fx, iadd<T>(ptr, amount) -> ret);
 572         };
 573         _ if intrinsic.starts_with("atomic_xsub"), <T> (v ptr, v amount) {
 574             atomic_binop_return_old! (fx, isub<T>(ptr, amount) -> ret);
 575         };
 576         _ if intrinsic.starts_with("atomic_and"), <T> (v ptr, v src) {
 577             atomic_binop_return_old! (fx, band<T>(ptr, src) -> ret);
 578         };
 579         _ if intrinsic.starts_with("atomic_nand"), <T> (v ptr, v src) {
 580             atomic_binop_return_old! (fx, band_not<T>(ptr, src) -> ret);
 581         };
 582         _ if intrinsic.starts_with("atomic_or"), <T> (v ptr, v src) {
 583             atomic_binop_return_old! (fx, bor<T>(ptr, src) -> ret);
 584         };
 585         _ if intrinsic.starts_with("atomic_xor"), <T> (v ptr, v src) {
 586             atomic_binop_return_old! (fx, bxor<T>(ptr, src) -> ret);
 587         };
 588
 589         _ if intrinsic.starts_with("atomic_max"), <T> (v ptr, v src) {
 590             atomic_minmax!(fx, IntCC::SignedGreaterThan, <T> (ptr, src) -> ret);
 591         };
 592         _ if intrinsic.starts_with("atomic_umax"), <T> (v ptr, v src) {
 593             atomic_minmax!(fx, IntCC::UnsignedGreaterThan, <T> (ptr, src) -> ret);
 594         };
 595         _ if intrinsic.starts_with("atomic_min"), <T> (v ptr, v src) {
 596             atomic_minmax!(fx, IntCC::SignedLessThan, <T> (ptr, src) -> ret);
 597         };
 598         _ if intrinsic.starts_with("atomic_umin"), <T> (v ptr, v src) {
 599             atomic_minmax!(fx, IntCC::UnsignedLessThan, <T> (ptr, src) -> ret);
 600         };
 601
 602         expf32, (c flt) {
 603             let res = fx.easy_call("expf", &[flt], fx.tcx.types.f32);
 604             ret.write_cvalue(fx, res);
 605         };
 606         expf64, (c flt) {
 607             let res = fx.easy_call("exp", &[flt], fx.tcx.types.f64);
 608             ret.write_cvalue(fx, res);
 609         };
 610         exp2f32, (c flt) {
 611             let res = fx.easy_call("exp2f", &[flt], fx.tcx.types.f32);
 612             ret.write_cvalue(fx, res);
 613         };
 614         exp2f64, (c flt) {
 615             let res = fx.easy_call("exp2", &[flt], fx.tcx.types.f64);
 616             ret.write_cvalue(fx, res);
 617         };
 618         fabsf32, (c flt) {
 619             let res = fx.easy_call("fabsf", &[flt], fx.tcx.types.f32);
 620             ret.write_cvalue(fx, res);
 621         };
 622         fabsf64, (c flt) {
 623             let res = fx.easy_call("fabs", &[flt], fx.tcx.types.f64);
 624             ret.write_cvalue(fx, res);
 625         };
 626         sqrtf32, (c flt) {
 627             let res = fx.easy_call("sqrtf", &[flt], fx.tcx.types.f32);
 628             ret.write_cvalue(fx, res);
 629         };
 630         sqrtf64, (c flt) {
 631             let res = fx.easy_call("sqrt", &[flt], fx.tcx.types.f64);
 632             ret.write_cvalue(fx, res);
 633         };
 634         floorf32, (c flt) {
 635             let res = fx.easy_call("floorf", &[flt], fx.tcx.types.f32);
 636             ret.write_cvalue(fx, res);
 637         };
 638         floorf64, (c flt) {
 639             let res = fx.easy_call("floor", &[flt], fx.tcx.types.f64);
 640             ret.write_cvalue(fx, res);
 641         };
 642         ceilf32, (c flt) {
 643             let res = fx.easy_call("ceilf", &[flt], fx.tcx.types.f32);
 644             ret.write_cvalue(fx, res);
 645         };
 646         ceilf64, (c flt) {
 647             let res = fx.easy_call("ceil", &[flt], fx.tcx.types.f64);
 648             ret.write_cvalue(fx, res);
 649         };
 650
 651         minnumf32, (c a, c b) {
 652             let res = fx.easy_call("fminf", &[a, b], fx.tcx.types.f32);
 653             ret.write_cvalue(fx, res);
 654         };
 655         minnumf64, (c a, c b) {
 656             let res = fx.easy_call("fmin", &[a, b], fx.tcx.types.f64);
 657             ret.write_cvalue(fx, res);
 658         };
 659         maxnumf32, (c a, c b) {
 660             let res = fx.easy_call("fmaxf", &[a, b], fx.tcx.types.f32);
 661             ret.write_cvalue(fx, res);
 662         };
 663         maxnumf64, (c a, c b) {
 664             let res = fx.easy_call("fmax", &[a, b], fx.tcx.types.f64);
 665             ret.write_cvalue(fx, res);
 666         };
 667
 668     }
 669
 670     if let Some((_, dest)) = destination {
 671         let ret_ebb = fx.get_ebb(dest);
 672         fx.bcx.ins().jump(ret_ebb, &[]);
 673     } else {
 674         trap_unreachable(fx, "[corruption] Diverging intrinsic returned.");
 675     }
 676 }