compiler/rustc_codegen_cranelift/src/common.rs

   1 use cranelift_codegen::isa::TargetFrontendConfig;
   2 use rustc_index::vec::IndexVec;
   3 use rustc_middle::ty::layout::{
   4     FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers,
   5 };
   6 use rustc_middle::ty::SymbolName;
   7 use rustc_target::abi::call::FnAbi;
   8 use rustc_target::abi::{Integer, Primitive};
   9 use rustc_target::spec::{HasTargetSpec, Target};
  10
  11 use crate::constant::ConstantCx;
  12 use crate::prelude::*;
  13
  14 pub(crate) fn pointer_ty(tcx: TyCtxt<'_>) -> types::Type {
  15     match tcx.data_layout.pointer_size.bits() {
  16         16 => types::I16,
  17         32 => types::I32,
  18         64 => types::I64,
  19         bits => bug!("ptr_sized_integer: unknown pointer bit size {}", bits),
  20     }
  21 }
  22
  23 pub(crate) fn scalar_to_clif_type(tcx: TyCtxt<'_>, scalar: Scalar) -> Type {
  24     match scalar.value {
  25         Primitive::Int(int, _sign) => match int {
  26             Integer::I8 => types::I8,
  27             Integer::I16 => types::I16,
  28             Integer::I32 => types::I32,
  29             Integer::I64 => types::I64,
  30             Integer::I128 => types::I128,
  31         },
  32         Primitive::F32 => types::F32,
  33         Primitive::F64 => types::F64,
  34         Primitive::Pointer => pointer_ty(tcx),
  35     }
  36 }
  37
  38 fn clif_type_from_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Option<types::Type> {
  39     Some(match ty.kind() {
  40         ty::Bool => types::I8,
  41         ty::Uint(size) => match size {
  42             UintTy::U8 => types::I8,
  43             UintTy::U16 => types::I16,
  44             UintTy::U32 => types::I32,
  45             UintTy::U64 => types::I64,
  46             UintTy::U128 => types::I128,
  47             UintTy::Usize => pointer_ty(tcx),
  48         },
  49         ty::Int(size) => match size {
  50             IntTy::I8 => types::I8,
  51             IntTy::I16 => types::I16,
  52             IntTy::I32 => types::I32,
  53             IntTy::I64 => types::I64,
  54             IntTy::I128 => types::I128,
  55             IntTy::Isize => pointer_ty(tcx),
  56         },
  57         ty::Char => types::I32,
  58         ty::Float(size) => match size {
  59             FloatTy::F32 => types::F32,
  60             FloatTy::F64 => types::F64,
  61         },
  62         ty::FnPtr(_) => pointer_ty(tcx),
  63         ty::RawPtr(TypeAndMut { ty: pointee_ty, mutbl: _ }) | ty::Ref(_, pointee_ty, _) => {
  64             if has_ptr_meta(tcx, *pointee_ty) {
  65                 return None;
  66             } else {
  67                 pointer_ty(tcx)
  68             }
  69         }
  70         ty::Adt(adt_def, _) if adt_def.repr.simd() => {
  71             let (element, count) = match &tcx.layout_of(ParamEnv::reveal_all().and(ty)).unwrap().abi
  72             {
  73                 Abi::Vector { element, count } => (element.clone(), *count),
  74                 _ => unreachable!(),
  75             };
  76
  77             match scalar_to_clif_type(tcx, element).by(u16::try_from(count).unwrap()) {
  78                 // Cranelift currently only implements icmp for 128bit vectors.
  79                 Some(vector_ty) if vector_ty.bits() == 128 => vector_ty,
  80                 _ => return None,
  81             }
  82         }
  83         ty::Param(_) => bug!("ty param {:?}", ty),
  84         _ => return None,
  85     })
  86 }
  87
  88 fn clif_pair_type_from_ty<'tcx>(
  89     tcx: TyCtxt<'tcx>,
  90     ty: Ty<'tcx>,
  91 ) -> Option<(types::Type, types::Type)> {
  92     Some(match ty.kind() {
  93         ty::Tuple(substs) if substs.len() == 2 => {
  94             let mut types = substs.types();
  95             let a = clif_type_from_ty(tcx, types.next().unwrap())?;
  96             let b = clif_type_from_ty(tcx, types.next().unwrap())?;
  97             if a.is_vector() || b.is_vector() {
  98                 return None;
  99             }
 100             (a, b)
 101         }
 102         ty::RawPtr(TypeAndMut { ty: pointee_ty, mutbl: _ }) | ty::Ref(_, pointee_ty, _) => {
 103             if has_ptr_meta(tcx, *pointee_ty) {
 104                 (pointer_ty(tcx), pointer_ty(tcx))
 105             } else {
 106                 return None;
 107             }
 108         }
 109         _ => return None,
 110     })
 111 }
 112
 113 /// Is a pointer to this type a fat ptr?
 114 pub(crate) fn has_ptr_meta<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
 115     let ptr_ty = tcx.mk_ptr(TypeAndMut { ty, mutbl: rustc_hir::Mutability::Not });
 116     match &tcx.layout_of(ParamEnv::reveal_all().and(ptr_ty)).unwrap().abi {
 117         Abi::Scalar(_) => false,
 118         Abi::ScalarPair(_, _) => true,
 119         abi => unreachable!("Abi of ptr to {:?} is {:?}???", ty, abi),
 120     }
 121 }
 122
 123 pub(crate) fn codegen_icmp_imm(
 124     fx: &mut FunctionCx<'_, '_, '_>,
 125     intcc: IntCC,
 126     lhs: Value,
 127     rhs: i128,
 128 ) -> Value {
 129     let lhs_ty = fx.bcx.func.dfg.value_type(lhs);
 130     if lhs_ty == types::I128 {
 131         // FIXME legalize `icmp_imm.i128` in Cranelift
 132
 133         let (lhs_lsb, lhs_msb) = fx.bcx.ins().isplit(lhs);
 134         let (rhs_lsb, rhs_msb) = (rhs as u128 as u64 as i64, (rhs as u128 >> 64) as u64 as i64);
 135
 136         match intcc {
 137             IntCC::Equal => {
 138                 let lsb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_lsb, rhs_lsb);
 139                 let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb);
 140                 fx.bcx.ins().band(lsb_eq, msb_eq)
 141             }
 142             IntCC::NotEqual => {
 143                 let lsb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_lsb, rhs_lsb);
 144                 let msb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_msb, rhs_msb);
 145                 fx.bcx.ins().bor(lsb_ne, msb_ne)
 146             }
 147             _ => {
 148                 // if msb_eq {
 149                 //     lsb_cc
 150                 // } else {
 151                 //     msb_cc
 152                 // }
 153
 154                 let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb);
 155                 let lsb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_lsb, rhs_lsb);
 156                 let msb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_msb, rhs_msb);
 157
 158                 fx.bcx.ins().select(msb_eq, lsb_cc, msb_cc)
 159             }
 160         }
 161     } else {
 162         let rhs = i64::try_from(rhs).expect("codegen_icmp_imm rhs out of range for <128bit int");
 163         fx.bcx.ins().icmp_imm(intcc, lhs, rhs)
 164     }
 165 }
 166
 167 pub(crate) fn type_min_max_value(
 168     bcx: &mut FunctionBuilder<'_>,
 169     ty: Type,
 170     signed: bool,
 171 ) -> (Value, Value) {
 172     assert!(ty.is_int());
 173
 174     if ty == types::I128 {
 175         if signed {
 176             let min = i128::MIN as u128;
 177             let min_lsb = bcx.ins().iconst(types::I64, min as u64 as i64);
 178             let min_msb = bcx.ins().iconst(types::I64, (min >> 64) as u64 as i64);
 179             let min = bcx.ins().iconcat(min_lsb, min_msb);
 180
 181             let max = i128::MAX as u128;
 182             let max_lsb = bcx.ins().iconst(types::I64, max as u64 as i64);
 183             let max_msb = bcx.ins().iconst(types::I64, (max >> 64) as u64 as i64);
 184             let max = bcx.ins().iconcat(max_lsb, max_msb);
 185
 186             return (min, max);
 187         } else {
 188             let min_half = bcx.ins().iconst(types::I64, 0);
 189             let min = bcx.ins().iconcat(min_half, min_half);
 190
 191             let max_half = bcx.ins().iconst(types::I64, u64::MAX as i64);
 192             let max = bcx.ins().iconcat(max_half, max_half);
 193
 194             return (min, max);
 195         }
 196     }
 197
 198     let min = match (ty, signed) {
 199         (types::I8, false) | (types::I16, false) | (types::I32, false) | (types::I64, false) => {
 200             0i64
 201         }
 202         (types::I8, true) => i64::from(i8::MIN),
 203         (types::I16, true) => i64::from(i16::MIN),
 204         (types::I32, true) => i64::from(i32::MIN),
 205         (types::I64, true) => i64::MIN,
 206         _ => unreachable!(),
 207     };
 208
 209     let max = match (ty, signed) {
 210         (types::I8, false) => i64::from(u8::MAX),
 211         (types::I16, false) => i64::from(u16::MAX),
 212         (types::I32, false) => i64::from(u32::MAX),
 213         (types::I64, false) => u64::MAX as i64,
 214         (types::I8, true) => i64::from(i8::MAX),
 215         (types::I16, true) => i64::from(i16::MAX),
 216         (types::I32, true) => i64::from(i32::MAX),
 217         (types::I64, true) => i64::MAX,
 218         _ => unreachable!(),
 219     };
 220
 221     let (min, max) = (bcx.ins().iconst(ty, min), bcx.ins().iconst(ty, max));
 222
 223     (min, max)
 224 }
 225
 226 pub(crate) fn type_sign(ty: Ty<'_>) -> bool {
 227     match ty.kind() {
 228         ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 229         ty::Int(..) => true,
 230         ty::Float(..) => false, // `signed` is unused for floats
 231         _ => panic!("{}", ty),
 232     }
 233 }
 234
 235 pub(crate) struct FunctionCx<'m, 'clif, 'tcx: 'm> {
 236     pub(crate) cx: &'clif mut crate::CodegenCx<'tcx>,
 237     pub(crate) module: &'m mut dyn Module,
 238     pub(crate) tcx: TyCtxt<'tcx>,
 239     pub(crate) target_config: TargetFrontendConfig, // Cached from module
 240     pub(crate) pointer_type: Type,                  // Cached from module
 241     pub(crate) constants_cx: ConstantCx,
 242
 243     pub(crate) instance: Instance<'tcx>,
 244     pub(crate) symbol_name: SymbolName<'tcx>,
 245     pub(crate) mir: &'tcx Body<'tcx>,
 246     pub(crate) fn_abi: Option<&'tcx FnAbi<'tcx, Ty<'tcx>>>,
 247
 248     pub(crate) bcx: FunctionBuilder<'clif>,
 249     pub(crate) block_map: IndexVec<BasicBlock, Block>,
 250     pub(crate) local_map: IndexVec<Local, CPlace<'tcx>>,
 251
 252     /// When `#[track_caller]` is used, the implicit caller location is stored in this variable.
 253     pub(crate) caller_location: Option<CValue<'tcx>>,
 254
 255     pub(crate) clif_comments: crate::pretty_clif::CommentWriter,
 256     pub(crate) source_info_set: indexmap::IndexSet<SourceInfo>,
 257
 258     /// This should only be accessed by `CPlace::new_var`.
 259     pub(crate) next_ssa_var: u32,
 260 }
 261
 262 impl<'tcx> LayoutOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
 263     type LayoutOfResult = TyAndLayout<'tcx>;
 264
 265     #[inline]
 266     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
 267         RevealAllLayoutCx(self.tcx).handle_layout_err(err, span, ty)
 268     }
 269 }
 270
 271 impl<'tcx> FnAbiOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
 272     type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
 273
 274     #[inline]
 275     fn handle_fn_abi_err(
 276         &self,
 277         err: FnAbiError<'tcx>,
 278         span: Span,
 279         fn_abi_request: FnAbiRequest<'tcx>,
 280     ) -> ! {
 281         RevealAllLayoutCx(self.tcx).handle_fn_abi_err(err, span, fn_abi_request)
 282     }
 283 }
 284
 285 impl<'tcx> layout::HasTyCtxt<'tcx> for FunctionCx<'_, '_, 'tcx> {
 286     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
 287         self.tcx
 288     }
 289 }
 290
 291 impl<'tcx> rustc_target::abi::HasDataLayout for FunctionCx<'_, '_, 'tcx> {
 292     fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout {
 293         &self.tcx.data_layout
 294     }
 295 }
 296
 297 impl<'tcx> layout::HasParamEnv<'tcx> for FunctionCx<'_, '_, 'tcx> {
 298     fn param_env(&self) -> ParamEnv<'tcx> {
 299         ParamEnv::reveal_all()
 300     }
 301 }
 302
 303 impl<'tcx> HasTargetSpec for FunctionCx<'_, '_, 'tcx> {
 304     fn target_spec(&self) -> &Target {
 305         &self.tcx.sess.target
 306     }
 307 }
 308
 309 impl<'tcx> FunctionCx<'_, '_, 'tcx> {
 310     pub(crate) fn monomorphize<T>(&self, value: T) -> T
 311     where
 312         T: TypeFoldable<'tcx> + Copy,
 313     {
 314         self.instance.subst_mir_and_normalize_erasing_regions(
 315             self.tcx,
 316             ty::ParamEnv::reveal_all(),
 317             value,
 318         )
 319     }
 320
 321     pub(crate) fn clif_type(&self, ty: Ty<'tcx>) -> Option<Type> {
 322         clif_type_from_ty(self.tcx, ty)
 323     }
 324
 325     pub(crate) fn clif_pair_type(&self, ty: Ty<'tcx>) -> Option<(Type, Type)> {
 326         clif_pair_type_from_ty(self.tcx, ty)
 327     }
 328
 329     pub(crate) fn get_block(&self, bb: BasicBlock) -> Block {
 330         *self.block_map.get(bb).unwrap()
 331     }
 332
 333     pub(crate) fn get_local_place(&mut self, local: Local) -> CPlace<'tcx> {
 334         *self.local_map.get(local).unwrap_or_else(|| {
 335             panic!("Local {:?} doesn't exist", local);
 336         })
 337     }
 338
 339     pub(crate) fn set_debug_loc(&mut self, source_info: mir::SourceInfo) {
 340         let (index, _) = self.source_info_set.insert_full(source_info);
 341         self.bcx.set_srcloc(SourceLoc::new(index as u32));
 342     }
 343
 344     pub(crate) fn get_caller_location(&mut self, span: Span) -> CValue<'tcx> {
 345         if let Some(loc) = self.caller_location {
 346             // `#[track_caller]` is used; return caller location instead of current location.
 347             return loc;
 348         }
 349
 350         let topmost = span.ctxt().outer_expn().expansion_cause().unwrap_or(span);
 351         let caller = self.tcx.sess.source_map().lookup_char_pos(topmost.lo());
 352         let const_loc = self.tcx.const_caller_location((
 353             rustc_span::symbol::Symbol::intern(
 354                 &caller.file.name.prefer_remapped().to_string_lossy(),
 355             ),
 356             caller.line as u32,
 357             caller.col_display as u32 + 1,
 358         ));
 359         crate::constant::codegen_const_value(self, const_loc, self.tcx.caller_location_ty())
 360     }
 361
 362     pub(crate) fn anonymous_str(&mut self, msg: &str) -> Value {
 363         let mut data_ctx = DataContext::new();
 364         data_ctx.define(msg.as_bytes().to_vec().into_boxed_slice());
 365         let msg_id = self.module.declare_anonymous_data(false, false).unwrap();
 366
 367         // Ignore DuplicateDefinition error, as the data will be the same
 368         let _ = self.module.define_data(msg_id, &data_ctx);
 369
 370         let local_msg_id = self.module.declare_data_in_func(msg_id, self.bcx.func);
 371         if self.clif_comments.enabled() {
 372             self.add_comment(local_msg_id, msg);
 373         }
 374         self.bcx.ins().global_value(self.pointer_type, local_msg_id)
 375     }
 376 }
 377
 378 pub(crate) struct RevealAllLayoutCx<'tcx>(pub(crate) TyCtxt<'tcx>);
 379
 380 impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
 381     type LayoutOfResult = TyAndLayout<'tcx>;
 382
 383     #[inline]
 384     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
 385         if let layout::LayoutError::SizeOverflow(_) = err {
 386             self.0.sess.span_fatal(span, &err.to_string())
 387         } else {
 388             span_bug!(span, "failed to get layout for `{}`: {}", ty, err)
 389         }
 390     }
 391 }
 392
 393 impl<'tcx> FnAbiOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
 394     type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
 395
 396     #[inline]
 397     fn handle_fn_abi_err(
 398         &self,
 399         err: FnAbiError<'tcx>,
 400         span: Span,
 401         fn_abi_request: FnAbiRequest<'tcx>,
 402     ) -> ! {
 403         if let FnAbiError::Layout(LayoutError::SizeOverflow(_)) = err {
 404             self.0.sess.span_fatal(span, &err.to_string())
 405         } else {
 406             match fn_abi_request {
 407                 FnAbiRequest::OfFnPtr { sig, extra_args } => {
 408                     span_bug!(
 409                         span,
 410                         "`fn_abi_of_fn_ptr({}, {:?})` failed: {}",
 411                         sig,
 412                         extra_args,
 413                         err
 414                     );
 415                 }
 416                 FnAbiRequest::OfInstance { instance, extra_args } => {
 417                     span_bug!(
 418                         span,
 419                         "`fn_abi_of_instance({}, {:?})` failed: {}",
 420                         instance,
 421                         extra_args,
 422                         err
 423                     );
 424                 }
 425             }
 426         }
 427     }
 428 }
 429
 430 impl<'tcx> layout::HasTyCtxt<'tcx> for RevealAllLayoutCx<'tcx> {
 431     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
 432         self.0
 433     }
 434 }
 435
 436 impl<'tcx> rustc_target::abi::HasDataLayout for RevealAllLayoutCx<'tcx> {
 437     fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout {
 438         &self.0.data_layout
 439     }
 440 }
 441
 442 impl<'tcx> layout::HasParamEnv<'tcx> for RevealAllLayoutCx<'tcx> {
 443     fn param_env(&self) -> ParamEnv<'tcx> {
 444         ParamEnv::reveal_all()
 445     }
 446 }
 447
 448 impl<'tcx> HasTargetSpec for RevealAllLayoutCx<'tcx> {
 449     fn target_spec(&self) -> &Target {
 450         &self.0.sess.target
 451     }
 452 }