src/intrinsics.rs

   1
   2 use crate::prelude::*;
   3
   4 macro_rules! intrinsic_pat {
   5     (_) => {
   6         _
   7     };
   8     ($name:ident) => {
   9         stringify!($name)
  10     }
  11 }
  12
  13 macro_rules! intrinsic_arg {
  14     (c $fx:expr, $arg:ident) => {
  15         $arg
  16     };
  17     (v $fx:expr, $arg:ident) => {
  18         $arg.load_value($fx)
  19     };
  20 }
  21
  22 macro_rules! intrinsic_match {
  23     ($fx:expr, $intrinsic:expr, $args:expr, $(
  24         $($name:tt)|+ $(if $cond:expr)?, |$($a:ident $arg:ident),*| $content:block;
  25     )*) => {
  26         match $intrinsic {
  27             $(
  28                 $(intrinsic_pat!($name))|* $(if $cond)? => {
  29                     if let [$($arg),*] = *$args {
  30                         #[allow(unused_parens)]
  31                         {
  32                             let ($($arg),*) = (
  33                                 $(intrinsic_arg!($a $fx, $arg)),*
  34                             );
  35                             $content
  36                         }
  37                     } else {
  38                         bug!("wrong number of args for intrinsic {:?}", $intrinsic);
  39                     }
  40                 }
  41             )*
  42             _ => unimpl!("unsupported intrinsic {}", $intrinsic),
  43         }
  44     };
  45 }
  46
  47 pub fn codegen_intrinsic_call<'a, 'tcx: 'a>(
  48     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
  49     def_id: DefId,
  50     substs: &'tcx Substs,
  51     args: Vec<CValue<'tcx>>,
  52     destination: Option<(CPlace<'tcx>, BasicBlock)>,
  53 ) {
  54     let intrinsic = fx.tcx.item_name(def_id).as_str();
  55     let intrinsic = &intrinsic[..];
  56
  57     let ret = match destination {
  58         Some((place, _)) => place,
  59         None => {
  60             // Insert non returning intrinsics here
  61             match intrinsic {
  62                 "abort" => {
  63                     fx.bcx.ins().trap(TrapCode::User(!0 - 1));
  64                 }
  65                 "unreachable" => {
  66                     fx.bcx.ins().trap(TrapCode::User(!0 - 1));
  67                 }
  68                 _ => unimplemented!("unsupported instrinsic {}", intrinsic),
  69             }
  70             return;
  71         }
  72     };
  73
  74     let u64_layout = fx.layout_of(fx.tcx.types.u64);
  75     let usize_layout = fx.layout_of(fx.tcx.types.usize);
  76
  77     intrinsic_match! {
  78         fx, intrinsic, args,
  79
  80         assume, |c _a| {};
  81         arith_offset, |v base, v offset| {
  82             let res = fx.bcx.ins().iadd(base, offset);
  83             let res = CValue::ByVal(res, ret.layout());
  84             ret.write_cvalue(fx, res);
  85         };
  86         likely | unlikely, |c a| {
  87             ret.write_cvalue(fx, a);
  88         };
  89         copy | copy_nonoverlapping, |v src, v dst, v count| {
  90             let elem_ty = substs.type_at(0);
  91             let elem_size: u64 = fx.layout_of(elem_ty).size.bytes();
  92             let elem_size = fx
  93                 .bcx
  94                 .ins()
  95                 .iconst(fx.module.pointer_type(), elem_size as i64);
  96             assert_eq!(args.len(), 3);
  97             let byte_amount = fx.bcx.ins().imul(count, elem_size);
  98
  99             if intrinsic.ends_with("_nonoverlapping") {
 100                 fx.bcx.call_memcpy(fx.isa, dst, src, byte_amount);
 101             } else {
 102                 fx.bcx.call_memmove(fx.isa, dst, src, byte_amount);
 103             }
 104         };
 105         discriminant_value, |c val| {
 106             let discr = crate::base::trans_get_discriminant(fx, args[0], ret.layout());
 107             ret.write_cvalue(fx, discr);
 108         };
 109         size_of, | | {
 110             let size_of = fx.layout_of(substs.type_at(0)).size.bytes();
 111             let size_of = CValue::const_val(fx, usize_layout.ty, size_of as i64);
 112             ret.write_cvalue(fx, size_of);
 113         };
 114         size_of_val, |c ptr| {
 115             let layout = fx.layout_of(substs.type_at(0));
 116             let size = match &layout.ty.sty {
 117                 _ if !layout.is_unsized() => fx
 118                     .bcx
 119                     .ins()
 120                     .iconst(fx.module.pointer_type(), layout.size.bytes() as i64),
 121                 ty::Slice(elem) => {
 122                     let len = ptr.load_value_pair(fx).1;
 123                     let elem_size = fx.layout_of(elem).size.bytes();
 124                     fx.bcx.ins().imul_imm(len, elem_size as i64)
 125                 }
 126                 ty::Dynamic(..) => crate::vtable::size_of_obj(fx, ptr),
 127                 ty => bug!("size_of_val for unknown unsized type {:?}", ty),
 128             };
 129             ret.write_cvalue(fx, CValue::ByVal(size, usize_layout));
 130         };
 131         min_align_of, | | {
 132             let min_align = fx.layout_of(substs.type_at(0)).align.abi();
 133             let min_align = CValue::const_val(fx, usize_layout.ty, min_align as i64);
 134             ret.write_cvalue(fx, min_align);
 135         };
 136         min_align_of_val, |c ptr| {
 137             let layout = fx.layout_of(substs.type_at(0));
 138             let align = match &layout.ty.sty {
 139                 _ if !layout.is_unsized() => fx
 140                     .bcx
 141                     .ins()
 142                     .iconst(fx.module.pointer_type(), layout.align.abi() as i64),
 143                 ty::Slice(elem) => {
 144                     let align = fx.layout_of(elem).align.abi() as i64;
 145                     fx.bcx.ins().iconst(fx.module.pointer_type(), align)
 146                 }
 147                 ty::Dynamic(..) => crate::vtable::min_align_of_obj(fx, ptr),
 148                 ty => unimplemented!("min_align_of_val for {:?}", ty),
 149             };
 150             ret.write_cvalue(fx, CValue::ByVal(align, usize_layout));
 151         };
 152         type_id, | | {
 153             let type_id = fx.tcx.type_id_hash(substs.type_at(0));
 154             let type_id = CValue::const_val(fx, u64_layout.ty, type_id as i64);
 155             ret.write_cvalue(fx, type_id);
 156         };
 157         _ if intrinsic.starts_with("unchecked_"), |c x, c y| {
 158             let bin_op = match intrinsic {
 159                 "unchecked_div" => BinOp::Div,
 160                 "unchecked_rem" => BinOp::Rem,
 161                 "unchecked_shl" => BinOp::Shl,
 162                 "unchecked_shr" => BinOp::Shr,
 163                 _ => unimplemented!("intrinsic {}", intrinsic),
 164             };
 165             let res = match ret.layout().ty.sty {
 166                 ty::Uint(_) => crate::base::trans_int_binop(
 167                     fx,
 168                     bin_op,
 169                     x,
 170                     y,
 171                     ret.layout().ty,
 172                     false,
 173                 ),
 174                 ty::Int(_) => crate::base::trans_int_binop(
 175                     fx,
 176                     bin_op,
 177                     x,
 178                     y,
 179                     ret.layout().ty,
 180                     true,
 181                 ),
 182                 _ => panic!(),
 183             };
 184             ret.write_cvalue(fx, res);
 185         };
 186         _ if intrinsic.ends_with("_with_overflow"), |c x, c y| {
 187             assert_eq!(x.layout().ty, y.layout().ty);
 188             let bin_op = match intrinsic {
 189                 "add_with_overflow" => BinOp::Add,
 190                 "sub_with_overflow" => BinOp::Sub,
 191                 "mul_with_overflow" => BinOp::Mul,
 192                 _ => unimplemented!("intrinsic {}", intrinsic),
 193             };
 194             let res = match args[0].layout().ty.sty {
 195                 ty::Uint(_) => crate::base::trans_checked_int_binop(
 196                     fx,
 197                     bin_op,
 198                     x,
 199                     y,
 200                     ret.layout().ty,
 201                     false,
 202                 ),
 203                 ty::Int(_) => crate::base::trans_checked_int_binop(
 204                     fx,
 205                     bin_op,
 206                     x,
 207                     y,
 208                     ret.layout().ty,
 209                     true,
 210                 ),
 211                 _ => panic!(),
 212             };
 213             ret.write_cvalue(fx, res);
 214         };
 215         _ if intrinsic.starts_with("overflowing_"), |c x, c y| {
 216             assert_eq!(x.layout().ty, y.layout().ty);
 217             let bin_op = match intrinsic {
 218                 "overflowing_add" => BinOp::Add,
 219                 "overflowing_sub" => BinOp::Sub,
 220                 "overflowing_mul" => BinOp::Mul,
 221                 _ => unimplemented!("intrinsic {}", intrinsic),
 222             };
 223             let res = match x.layout().ty.sty {
 224                 ty::Uint(_) => crate::base::trans_int_binop(
 225                     fx,
 226                     bin_op,
 227                     x,
 228                     y,
 229                     ret.layout().ty,
 230                     false,
 231                 ),
 232                 ty::Int(_) => crate::base::trans_int_binop(
 233                     fx,
 234                     bin_op,
 235                     x,
 236                     y,
 237                     ret.layout().ty,
 238                     true,
 239                 ),
 240                 _ => panic!(),
 241             };
 242             ret.write_cvalue(fx, res);
 243         };
 244         offset, |v base, v offset| {
 245             let res = fx.bcx.ins().iadd(base, offset);
 246             ret.write_cvalue(fx, CValue::ByVal(res, args[0].layout()));
 247         };
 248         transmute, |c from| {
 249             let src_ty = substs.type_at(0);
 250             let dst_ty = substs.type_at(1);
 251             assert_eq!(from.layout().ty, src_ty);
 252             let addr = from.force_stack(fx);
 253             let dst_layout = fx.layout_of(dst_ty);
 254             ret.write_cvalue(fx, CValue::ByRef(addr, dst_layout))
 255         };
 256         init, | | {
 257             let ty = substs.type_at(0);
 258             let layout = fx.layout_of(ty);
 259             let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
 260                 kind: StackSlotKind::ExplicitSlot,
 261                 size: layout.size.bytes() as u32,
 262                 offset: None,
 263             });
 264             let addr = fx.bcx.ins().stack_addr(pointer_ty(fx.tcx), stack_slot, 0);
 265             let zero_val = fx.bcx.ins().iconst(types::I8, 0);
 266             let len_val = fx.bcx.ins().iconst(pointer_ty(fx.tcx), layout.size.bytes() as i64);
 267             fx.bcx.call_memset(fx.isa, addr, zero_val, len_val);
 268
 269             let uninit_place = CPlace::from_stack_slot(fx, stack_slot, ty);
 270             let uninit_val = uninit_place.to_cvalue(fx);
 271             ret.write_cvalue(fx, uninit_val);
 272         };
 273         uninit, | | {
 274             let ty = substs.type_at(0);
 275             let layout = fx.layout_of(ty);
 276             let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
 277                 kind: StackSlotKind::ExplicitSlot,
 278                 size: layout.size.bytes() as u32,
 279                 offset: None,
 280             });
 281
 282             let uninit_place = CPlace::from_stack_slot(fx, stack_slot, ty);
 283             let uninit_val = uninit_place.to_cvalue(fx);
 284             ret.write_cvalue(fx, uninit_val);
 285         };
 286         ctlz | ctlz_nonzero, |v arg| {
 287             let res = CValue::ByVal(fx.bcx.ins().clz(arg), args[0].layout());
 288             ret.write_cvalue(fx, res);
 289         };
 290         cttz | cttz_nonzero, |v arg| {
 291             let res = CValue::ByVal(fx.bcx.ins().clz(arg), args[0].layout());
 292             ret.write_cvalue(fx, res);
 293         };
 294         ctpop, |v arg| {
 295             let res = CValue::ByVal(fx.bcx.ins().popcnt(arg), args[0].layout());
 296             ret.write_cvalue(fx, res);
 297         };
 298         bitreverse, |v arg| {
 299             let res = CValue::ByVal(fx.bcx.ins().bitrev(arg), args[0].layout());
 300             ret.write_cvalue(fx, res);
 301         };
 302         needs_drop, | | {
 303             let ty = substs.type_at(0);
 304             let needs_drop = if ty.needs_drop(fx.tcx, ParamEnv::reveal_all()) {
 305                 1
 306             } else {
 307                 0
 308             };
 309             let needs_drop = CValue::const_val(fx, fx.tcx.types.bool, needs_drop);
 310             ret.write_cvalue(fx, needs_drop);
 311         };
 312         _ if intrinsic.starts_with("atomic_fence"), | | {};
 313         _ if intrinsic.starts_with("atomic_singlethreadfence"), | | {};
 314         _ if intrinsic.starts_with("atomic_load"), |c ptr| {
 315             let inner_layout =
 316                 fx.layout_of(ptr.layout().ty.builtin_deref(true).unwrap().ty);
 317             let val = CValue::ByRef(ptr.load_value(fx), inner_layout);
 318             ret.write_cvalue(fx, val);
 319         };
 320         _ if intrinsic.starts_with("atomic_store"), |v ptr, c val| {
 321             let dest = CPlace::Addr(ptr, None, val.layout());
 322             dest.write_cvalue(fx, val);
 323         };
 324         _ if intrinsic.starts_with("atomic_xadd"), |v ptr, v amount| {
 325             let clif_ty = fx.cton_type(substs.type_at(0)).unwrap();
 326             let old = fx.bcx.ins().load(clif_ty, MemFlags::new(), ptr, 0);
 327             let new = fx.bcx.ins().iadd(old, amount);
 328             fx.bcx.ins().store(MemFlags::new(), new, ptr, 0);
 329             ret.write_cvalue(fx, CValue::ByVal(old, fx.layout_of(substs.type_at(0))));
 330         };
 331         _ if intrinsic.starts_with("atomic_xsub"), |v ptr, v amount| {
 332             let clif_ty = fx.cton_type(substs.type_at(0)).unwrap();
 333             let old = fx.bcx.ins().load(clif_ty, MemFlags::new(), ptr, 0);
 334             let new = fx.bcx.ins().isub(old, amount);
 335             fx.bcx.ins().store(MemFlags::new(), new, ptr, 0);
 336             ret.write_cvalue(fx, CValue::ByVal(old, fx.layout_of(substs.type_at(0))));
 337         };
 338     }
 339
 340     if let Some((_, dest)) = destination {
 341         let ret_ebb = fx.get_ebb(dest);
 342         fx.bcx.ins().jump(ret_ebb, &[]);
 343     } else {
 344         fx.bcx.ins().trap(TrapCode::User(!0));
 345     }
 346 }