compiler/rustc_codegen_cranelift/src/common.rs

   1 use rustc_index::vec::IndexVec;
   2 use rustc_middle::ty::SymbolName;
   3 use rustc_target::abi::call::FnAbi;
   4 use rustc_target::abi::{Integer, Primitive};
   5 use rustc_target::spec::{HasTargetSpec, Target};
   6
   7 use crate::constant::ConstantCx;
   8 use crate::prelude::*;
   9
  10 pub(crate) fn pointer_ty(tcx: TyCtxt<'_>) -> types::Type {
  11     match tcx.data_layout.pointer_size.bits() {
  12         16 => types::I16,
  13         32 => types::I32,
  14         64 => types::I64,
  15         bits => bug!("ptr_sized_integer: unknown pointer bit size {}", bits),
  16     }
  17 }
  18
  19 pub(crate) fn scalar_to_clif_type(tcx: TyCtxt<'_>, scalar: Scalar) -> Type {
  20     match scalar.value {
  21         Primitive::Int(int, _sign) => match int {
  22             Integer::I8 => types::I8,
  23             Integer::I16 => types::I16,
  24             Integer::I32 => types::I32,
  25             Integer::I64 => types::I64,
  26             Integer::I128 => types::I128,
  27         },
  28         Primitive::F32 => types::F32,
  29         Primitive::F64 => types::F64,
  30         Primitive::Pointer => pointer_ty(tcx),
  31     }
  32 }
  33
  34 fn clif_type_from_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Option<types::Type> {
  35     Some(match ty.kind() {
  36         ty::Bool => types::I8,
  37         ty::Uint(size) => match size {
  38             UintTy::U8 => types::I8,
  39             UintTy::U16 => types::I16,
  40             UintTy::U32 => types::I32,
  41             UintTy::U64 => types::I64,
  42             UintTy::U128 => types::I128,
  43             UintTy::Usize => pointer_ty(tcx),
  44         },
  45         ty::Int(size) => match size {
  46             IntTy::I8 => types::I8,
  47             IntTy::I16 => types::I16,
  48             IntTy::I32 => types::I32,
  49             IntTy::I64 => types::I64,
  50             IntTy::I128 => types::I128,
  51             IntTy::Isize => pointer_ty(tcx),
  52         },
  53         ty::Char => types::I32,
  54         ty::Float(size) => match size {
  55             FloatTy::F32 => types::F32,
  56             FloatTy::F64 => types::F64,
  57         },
  58         ty::FnPtr(_) => pointer_ty(tcx),
  59         ty::RawPtr(TypeAndMut { ty: pointee_ty, mutbl: _ }) | ty::Ref(_, pointee_ty, _) => {
  60             if has_ptr_meta(tcx, pointee_ty) {
  61                 return None;
  62             } else {
  63                 pointer_ty(tcx)
  64             }
  65         }
  66         ty::Adt(adt_def, _) if adt_def.repr.simd() => {
  67             let (element, count) = match &tcx.layout_of(ParamEnv::reveal_all().and(ty)).unwrap().abi
  68             {
  69                 Abi::Vector { element, count } => (element.clone(), *count),
  70                 _ => unreachable!(),
  71             };
  72
  73             match scalar_to_clif_type(tcx, element).by(u16::try_from(count).unwrap()) {
  74                 // Cranelift currently only implements icmp for 128bit vectors.
  75                 Some(vector_ty) if vector_ty.bits() == 128 => vector_ty,
  76                 _ => return None,
  77             }
  78         }
  79         ty::Param(_) => bug!("ty param {:?}", ty),
  80         _ => return None,
  81     })
  82 }
  83
  84 fn clif_pair_type_from_ty<'tcx>(
  85     tcx: TyCtxt<'tcx>,
  86     ty: Ty<'tcx>,
  87 ) -> Option<(types::Type, types::Type)> {
  88     Some(match ty.kind() {
  89         ty::Tuple(substs) if substs.len() == 2 => {
  90             let mut types = substs.types();
  91             let a = clif_type_from_ty(tcx, types.next().unwrap())?;
  92             let b = clif_type_from_ty(tcx, types.next().unwrap())?;
  93             if a.is_vector() || b.is_vector() {
  94                 return None;
  95             }
  96             (a, b)
  97         }
  98         ty::RawPtr(TypeAndMut { ty: pointee_ty, mutbl: _ }) | ty::Ref(_, pointee_ty, _) => {
  99             if has_ptr_meta(tcx, pointee_ty) {
 100                 (pointer_ty(tcx), pointer_ty(tcx))
 101             } else {
 102                 return None;
 103             }
 104         }
 105         _ => return None,
 106     })
 107 }
 108
 109 /// Is a pointer to this type a fat ptr?
 110 pub(crate) fn has_ptr_meta<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
 111     let ptr_ty = tcx.mk_ptr(TypeAndMut { ty, mutbl: rustc_hir::Mutability::Not });
 112     match &tcx.layout_of(ParamEnv::reveal_all().and(ptr_ty)).unwrap().abi {
 113         Abi::Scalar(_) => false,
 114         Abi::ScalarPair(_, _) => true,
 115         abi => unreachable!("Abi of ptr to {:?} is {:?}???", ty, abi),
 116     }
 117 }
 118
 119 pub(crate) fn codegen_icmp_imm(
 120     fx: &mut FunctionCx<'_, '_, '_>,
 121     intcc: IntCC,
 122     lhs: Value,
 123     rhs: i128,
 124 ) -> Value {
 125     let lhs_ty = fx.bcx.func.dfg.value_type(lhs);
 126     if lhs_ty == types::I128 {
 127         // FIXME legalize `icmp_imm.i128` in Cranelift
 128
 129         let (lhs_lsb, lhs_msb) = fx.bcx.ins().isplit(lhs);
 130         let (rhs_lsb, rhs_msb) = (rhs as u128 as u64 as i64, (rhs as u128 >> 64) as u64 as i64);
 131
 132         match intcc {
 133             IntCC::Equal => {
 134                 let lsb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_lsb, rhs_lsb);
 135                 let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb);
 136                 fx.bcx.ins().band(lsb_eq, msb_eq)
 137             }
 138             IntCC::NotEqual => {
 139                 let lsb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_lsb, rhs_lsb);
 140                 let msb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_msb, rhs_msb);
 141                 fx.bcx.ins().bor(lsb_ne, msb_ne)
 142             }
 143             _ => {
 144                 // if msb_eq {
 145                 //     lsb_cc
 146                 // } else {
 147                 //     msb_cc
 148                 // }
 149
 150                 let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb);
 151                 let lsb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_lsb, rhs_lsb);
 152                 let msb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_msb, rhs_msb);
 153
 154                 fx.bcx.ins().select(msb_eq, lsb_cc, msb_cc)
 155             }
 156         }
 157     } else {
 158         let rhs = i64::try_from(rhs).expect("codegen_icmp_imm rhs out of range for <128bit int");
 159         fx.bcx.ins().icmp_imm(intcc, lhs, rhs)
 160     }
 161 }
 162
 163 pub(crate) fn type_min_max_value(
 164     bcx: &mut FunctionBuilder<'_>,
 165     ty: Type,
 166     signed: bool,
 167 ) -> (Value, Value) {
 168     assert!(ty.is_int());
 169
 170     if ty == types::I128 {
 171         if signed {
 172             let min = i128::MIN as u128;
 173             let min_lsb = bcx.ins().iconst(types::I64, min as u64 as i64);
 174             let min_msb = bcx.ins().iconst(types::I64, (min >> 64) as u64 as i64);
 175             let min = bcx.ins().iconcat(min_lsb, min_msb);
 176
 177             let max = i128::MAX as u128;
 178             let max_lsb = bcx.ins().iconst(types::I64, max as u64 as i64);
 179             let max_msb = bcx.ins().iconst(types::I64, (max >> 64) as u64 as i64);
 180             let max = bcx.ins().iconcat(max_lsb, max_msb);
 181
 182             return (min, max);
 183         } else {
 184             let min_half = bcx.ins().iconst(types::I64, 0);
 185             let min = bcx.ins().iconcat(min_half, min_half);
 186
 187             let max_half = bcx.ins().iconst(types::I64, u64::MAX as i64);
 188             let max = bcx.ins().iconcat(max_half, max_half);
 189
 190             return (min, max);
 191         }
 192     }
 193
 194     let min = match (ty, signed) {
 195         (types::I8, false) | (types::I16, false) | (types::I32, false) | (types::I64, false) => {
 196             0i64
 197         }
 198         (types::I8, true) => i64::from(i8::MIN),
 199         (types::I16, true) => i64::from(i16::MIN),
 200         (types::I32, true) => i64::from(i32::MIN),
 201         (types::I64, true) => i64::MIN,
 202         _ => unreachable!(),
 203     };
 204
 205     let max = match (ty, signed) {
 206         (types::I8, false) => i64::from(u8::MAX),
 207         (types::I16, false) => i64::from(u16::MAX),
 208         (types::I32, false) => i64::from(u32::MAX),
 209         (types::I64, false) => u64::MAX as i64,
 210         (types::I8, true) => i64::from(i8::MAX),
 211         (types::I16, true) => i64::from(i16::MAX),
 212         (types::I32, true) => i64::from(i32::MAX),
 213         (types::I64, true) => i64::MAX,
 214         _ => unreachable!(),
 215     };
 216
 217     let (min, max) = (bcx.ins().iconst(ty, min), bcx.ins().iconst(ty, max));
 218
 219     (min, max)
 220 }
 221
 222 pub(crate) fn type_sign(ty: Ty<'_>) -> bool {
 223     match ty.kind() {
 224         ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 225         ty::Int(..) => true,
 226         ty::Float(..) => false, // `signed` is unused for floats
 227         _ => panic!("{}", ty),
 228     }
 229 }
 230
 231 pub(crate) struct FunctionCx<'m, 'clif, 'tcx: 'm> {
 232     pub(crate) cx: &'clif mut crate::CodegenCx<'tcx>,
 233     pub(crate) module: &'m mut dyn Module,
 234     pub(crate) tcx: TyCtxt<'tcx>,
 235     pub(crate) pointer_type: Type, // Cached from module
 236     pub(crate) constants_cx: ConstantCx,
 237
 238     pub(crate) instance: Instance<'tcx>,
 239     pub(crate) symbol_name: SymbolName<'tcx>,
 240     pub(crate) mir: &'tcx Body<'tcx>,
 241     pub(crate) fn_abi: Option<FnAbi<'tcx, Ty<'tcx>>>,
 242
 243     pub(crate) bcx: FunctionBuilder<'clif>,
 244     pub(crate) block_map: IndexVec<BasicBlock, Block>,
 245     pub(crate) local_map: IndexVec<Local, CPlace<'tcx>>,
 246
 247     /// When `#[track_caller]` is used, the implicit caller location is stored in this variable.
 248     pub(crate) caller_location: Option<CValue<'tcx>>,
 249
 250     pub(crate) clif_comments: crate::pretty_clif::CommentWriter,
 251     pub(crate) source_info_set: indexmap::IndexSet<SourceInfo>,
 252
 253     /// This should only be accessed by `CPlace::new_var`.
 254     pub(crate) next_ssa_var: u32,
 255
 256     pub(crate) inline_asm_index: u32,
 257 }
 258
 259 impl<'tcx> LayoutOf for FunctionCx<'_, '_, 'tcx> {
 260     type Ty = Ty<'tcx>;
 261     type TyAndLayout = TyAndLayout<'tcx>;
 262
 263     fn layout_of(&self, ty: Ty<'tcx>) -> TyAndLayout<'tcx> {
 264         RevealAllLayoutCx(self.tcx).layout_of(ty)
 265     }
 266 }
 267
 268 impl<'tcx> layout::HasTyCtxt<'tcx> for FunctionCx<'_, '_, 'tcx> {
 269     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
 270         self.tcx
 271     }
 272 }
 273
 274 impl<'tcx> rustc_target::abi::HasDataLayout for FunctionCx<'_, '_, 'tcx> {
 275     fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout {
 276         &self.tcx.data_layout
 277     }
 278 }
 279
 280 impl<'tcx> layout::HasParamEnv<'tcx> for FunctionCx<'_, '_, 'tcx> {
 281     fn param_env(&self) -> ParamEnv<'tcx> {
 282         ParamEnv::reveal_all()
 283     }
 284 }
 285
 286 impl<'tcx> HasTargetSpec for FunctionCx<'_, '_, 'tcx> {
 287     fn target_spec(&self) -> &Target {
 288         &self.tcx.sess.target
 289     }
 290 }
 291
 292 impl<'tcx> FunctionCx<'_, '_, 'tcx> {
 293     pub(crate) fn monomorphize<T>(&self, value: T) -> T
 294     where
 295         T: TypeFoldable<'tcx> + Copy,
 296     {
 297         self.instance.subst_mir_and_normalize_erasing_regions(
 298             self.tcx,
 299             ty::ParamEnv::reveal_all(),
 300             value,
 301         )
 302     }
 303
 304     pub(crate) fn clif_type(&self, ty: Ty<'tcx>) -> Option<Type> {
 305         clif_type_from_ty(self.tcx, ty)
 306     }
 307
 308     pub(crate) fn clif_pair_type(&self, ty: Ty<'tcx>) -> Option<(Type, Type)> {
 309         clif_pair_type_from_ty(self.tcx, ty)
 310     }
 311
 312     pub(crate) fn get_block(&self, bb: BasicBlock) -> Block {
 313         *self.block_map.get(bb).unwrap()
 314     }
 315
 316     pub(crate) fn get_local_place(&mut self, local: Local) -> CPlace<'tcx> {
 317         *self.local_map.get(local).unwrap_or_else(|| {
 318             panic!("Local {:?} doesn't exist", local);
 319         })
 320     }
 321
 322     pub(crate) fn set_debug_loc(&mut self, source_info: mir::SourceInfo) {
 323         let (index, _) = self.source_info_set.insert_full(source_info);
 324         self.bcx.set_srcloc(SourceLoc::new(index as u32));
 325     }
 326
 327     pub(crate) fn get_caller_location(&mut self, span: Span) -> CValue<'tcx> {
 328         if let Some(loc) = self.caller_location {
 329             // `#[track_caller]` is used; return caller location instead of current location.
 330             return loc;
 331         }
 332
 333         let topmost = span.ctxt().outer_expn().expansion_cause().unwrap_or(span);
 334         let caller = self.tcx.sess.source_map().lookup_char_pos(topmost.lo());
 335         let const_loc = self.tcx.const_caller_location((
 336             rustc_span::symbol::Symbol::intern(
 337                 &caller.file.name.prefer_remapped().to_string_lossy(),
 338             ),
 339             caller.line as u32,
 340             caller.col_display as u32 + 1,
 341         ));
 342         crate::constant::codegen_const_value(self, const_loc, self.tcx.caller_location_ty())
 343     }
 344
 345     pub(crate) fn triple(&self) -> &target_lexicon::Triple {
 346         self.module.isa().triple()
 347     }
 348
 349     pub(crate) fn anonymous_str(&mut self, msg: &str) -> Value {
 350         let mut data_ctx = DataContext::new();
 351         data_ctx.define(msg.as_bytes().to_vec().into_boxed_slice());
 352         let msg_id = self.module.declare_anonymous_data(false, false).unwrap();
 353
 354         // Ignore DuplicateDefinition error, as the data will be the same
 355         let _ = self.module.define_data(msg_id, &data_ctx);
 356
 357         let local_msg_id = self.module.declare_data_in_func(msg_id, self.bcx.func);
 358         if self.clif_comments.enabled() {
 359             self.add_comment(local_msg_id, msg);
 360         }
 361         self.bcx.ins().global_value(self.pointer_type, local_msg_id)
 362     }
 363 }
 364
 365 pub(crate) struct RevealAllLayoutCx<'tcx>(pub(crate) TyCtxt<'tcx>);
 366
 367 impl<'tcx> LayoutOf for RevealAllLayoutCx<'tcx> {
 368     type Ty = Ty<'tcx>;
 369     type TyAndLayout = TyAndLayout<'tcx>;
 370
 371     fn layout_of(&self, ty: Ty<'tcx>) -> TyAndLayout<'tcx> {
 372         assert!(!ty.still_further_specializable());
 373         self.0.layout_of(ParamEnv::reveal_all().and(&ty)).unwrap_or_else(|e| {
 374             if let layout::LayoutError::SizeOverflow(_) = e {
 375                 self.0.sess.fatal(&e.to_string())
 376             } else {
 377                 bug!("failed to get layout for `{}`: {}", ty, e)
 378             }
 379         })
 380     }
 381 }
 382
 383 impl<'tcx> layout::HasTyCtxt<'tcx> for RevealAllLayoutCx<'tcx> {
 384     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
 385         self.0
 386     }
 387 }
 388
 389 impl<'tcx> rustc_target::abi::HasDataLayout for RevealAllLayoutCx<'tcx> {
 390     fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout {
 391         &self.0.data_layout
 392     }
 393 }
 394
 395 impl<'tcx> layout::HasParamEnv<'tcx> for RevealAllLayoutCx<'tcx> {
 396     fn param_env(&self) -> ParamEnv<'tcx> {
 397         ParamEnv::reveal_all()
 398     }
 399 }
 400
 401 impl<'tcx> HasTargetSpec for RevealAllLayoutCx<'tcx> {
 402     fn target_spec(&self) -> &Target {
 403         &self.0.sess.target
 404     }
 405 }