src/librustc_codegen_ssa/traits/type_.rs

   1 use super::misc::MiscMethods;
   2 use super::Backend;
   3 use super::HasCodegen;
   4 use crate::common::{self, TypeKind};
   5 use crate::mir::place::PlaceRef;
   6 use rustc::ty::layout::{self, Align, Size, TyLayout};
   7 use rustc::ty::{self, Ty};
   8 use rustc::util::nodemap::FxHashMap;
   9 use rustc_target::abi::call::{ArgType, CastTarget, FnType, Reg};
  10 use std::cell::RefCell;
  11 use syntax::ast;
  12
  13 // This depends on `Backend` and not `BackendTypes`, because consumers will probably want to use
  14 // `LayoutOf` or `HasTyCtxt`. This way, they don't have to add a constraint on it themselves.
  15 pub trait BaseTypeMethods<'tcx>: Backend<'tcx> {
  16     fn type_void(&self) -> Self::Type;
  17     fn type_metadata(&self) -> Self::Type;
  18     fn type_i1(&self) -> Self::Type;
  19     fn type_i8(&self) -> Self::Type;
  20     fn type_i16(&self) -> Self::Type;
  21     fn type_i32(&self) -> Self::Type;
  22     fn type_i64(&self) -> Self::Type;
  23     fn type_i128(&self) -> Self::Type;
  24
  25     // Creates an integer type with the given number of bits, e.g., i24
  26     fn type_ix(&self, num_bits: u64) -> Self::Type;
  27     fn type_isize(&self) -> Self::Type;
  28
  29     fn type_f32(&self) -> Self::Type;
  30     fn type_f64(&self) -> Self::Type;
  31     fn type_x86_mmx(&self) -> Self::Type;
  32
  33     fn type_func(&self, args: &[Self::Type], ret: Self::Type) -> Self::Type;
  34     fn type_variadic_func(&self, args: &[Self::Type], ret: Self::Type) -> Self::Type;
  35     fn type_struct(&self, els: &[Self::Type], packed: bool) -> Self::Type;
  36     fn type_array(&self, ty: Self::Type, len: u64) -> Self::Type;
  37     fn type_vector(&self, ty: Self::Type, len: u64) -> Self::Type;
  38     fn type_kind(&self, ty: Self::Type) -> TypeKind;
  39     fn type_ptr_to(&self, ty: Self::Type) -> Self::Type;
  40     fn element_type(&self, ty: Self::Type) -> Self::Type;
  41
  42     /// Returns the number of elements in `self` if it is a LLVM vector type.
  43     fn vector_length(&self, ty: Self::Type) -> usize;
  44
  45     fn func_params_types(&self, ty: Self::Type) -> Vec<Self::Type>;
  46     fn float_width(&self, ty: Self::Type) -> usize;
  47
  48     /// Retrieves the bit width of the integer type `self`.
  49     fn int_width(&self, ty: Self::Type) -> u64;
  50
  51     fn val_ty(&self, v: Self::Value) -> Self::Type;
  52     fn scalar_lltypes(&self) -> &RefCell<FxHashMap<Ty<'tcx>, Self::Type>>;
  53 }
  54
  55 pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
  56     fn type_bool(&self) -> Self::Type {
  57         self.type_i8()
  58     }
  59
  60     fn type_i8p(&self) -> Self::Type {
  61         self.type_ptr_to(self.type_i8())
  62     }
  63
  64     fn type_int(&self) -> Self::Type {
  65         match &self.sess().target.target.target_c_int_width[..] {
  66             "16" => self.type_i16(),
  67             "32" => self.type_i32(),
  68             "64" => self.type_i64(),
  69             width => bug!("Unsupported target_c_int_width: {}", width),
  70         }
  71     }
  72
  73     fn type_int_from_ty(&self, t: ast::IntTy) -> Self::Type {
  74         match t {
  75             ast::IntTy::Isize => self.type_isize(),
  76             ast::IntTy::I8 => self.type_i8(),
  77             ast::IntTy::I16 => self.type_i16(),
  78             ast::IntTy::I32 => self.type_i32(),
  79             ast::IntTy::I64 => self.type_i64(),
  80             ast::IntTy::I128 => self.type_i128(),
  81         }
  82     }
  83
  84     fn type_uint_from_ty(&self, t: ast::UintTy) -> Self::Type {
  85         match t {
  86             ast::UintTy::Usize => self.type_isize(),
  87             ast::UintTy::U8 => self.type_i8(),
  88             ast::UintTy::U16 => self.type_i16(),
  89             ast::UintTy::U32 => self.type_i32(),
  90             ast::UintTy::U64 => self.type_i64(),
  91             ast::UintTy::U128 => self.type_i128(),
  92         }
  93     }
  94
  95     fn type_float_from_ty(&self, t: ast::FloatTy) -> Self::Type {
  96         match t {
  97             ast::FloatTy::F32 => self.type_f32(),
  98             ast::FloatTy::F64 => self.type_f64(),
  99         }
 100     }
 101
 102     fn type_from_integer(&self, i: layout::Integer) -> Self::Type {
 103         use rustc::ty::layout::Integer::*;
 104         match i {
 105             I8 => self.type_i8(),
 106             I16 => self.type_i16(),
 107             I32 => self.type_i32(),
 108             I64 => self.type_i64(),
 109             I128 => self.type_i128(),
 110         }
 111     }
 112
 113     fn type_pointee_for_align(&self, align: Align) -> Self::Type {
 114         // FIXME(eddyb) We could find a better approximation if ity.align < align.
 115         let ity = layout::Integer::approximate_align(self, align);
 116         self.type_from_integer(ity)
 117     }
 118
 119     /// Return a LLVM type that has at most the required alignment,
 120     /// and exactly the required size, as a best-effort padding array.
 121     fn type_padding_filler(&self, size: Size, align: Align) -> Self::Type {
 122         let unit = layout::Integer::approximate_align(self, align);
 123         let size = size.bytes();
 124         let unit_size = unit.size().bytes();
 125         assert_eq!(size % unit_size, 0);
 126         self.type_array(self.type_from_integer(unit), size / unit_size)
 127     }
 128
 129     fn type_needs_drop(&self, ty: Ty<'tcx>) -> bool {
 130         common::type_needs_drop(self.tcx(), ty)
 131     }
 132
 133     fn type_is_sized(&self, ty: Ty<'tcx>) -> bool {
 134         common::type_is_sized(self.tcx(), ty)
 135     }
 136
 137     fn type_is_freeze(&self, ty: Ty<'tcx>) -> bool {
 138         common::type_is_freeze(self.tcx(), ty)
 139     }
 140
 141     fn type_has_metadata(&self, ty: Ty<'tcx>) -> bool {
 142         use syntax_pos::DUMMY_SP;
 143         if ty.is_sized(self.tcx().at(DUMMY_SP), ty::ParamEnv::reveal_all()) {
 144             return false;
 145         }
 146
 147         let tail = self.tcx().struct_tail(ty);
 148         match tail.sty {
 149             ty::Foreign(..) => false,
 150             ty::Str | ty::Slice(..) | ty::Dynamic(..) => true,
 151             _ => bug!("unexpected unsized tail: {:?}", tail.sty),
 152         }
 153     }
 154 }
 155
 156 impl<T> DerivedTypeMethods<'tcx> for T where Self: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {}
 157
 158 pub trait LayoutTypeMethods<'tcx>: Backend<'tcx> {
 159     fn backend_type(&self, layout: TyLayout<'tcx>) -> Self::Type;
 160     fn cast_backend_type(&self, ty: &CastTarget) -> Self::Type;
 161     fn fn_backend_type(&self, ty: &FnType<'tcx, Ty<'tcx>>) -> Self::Type;
 162     fn fn_ptr_backend_type(&self, ty: &FnType<'tcx, Ty<'tcx>>) -> Self::Type;
 163     fn reg_backend_type(&self, ty: &Reg) -> Self::Type;
 164     fn immediate_backend_type(&self, layout: TyLayout<'tcx>) -> Self::Type;
 165     fn is_backend_immediate(&self, layout: TyLayout<'tcx>) -> bool;
 166     fn is_backend_scalar_pair(&self, layout: TyLayout<'tcx>) -> bool;
 167     fn backend_field_index(&self, layout: TyLayout<'tcx>, index: usize) -> u64;
 168     fn scalar_pair_element_backend_type<'a>(
 169         &self,
 170         layout: TyLayout<'tcx>,
 171         index: usize,
 172         immediate: bool,
 173     ) -> Self::Type;
 174 }
 175
 176 pub trait ArgTypeMethods<'tcx>: HasCodegen<'tcx> {
 177     fn store_fn_arg(
 178         &mut self,
 179         ty: &ArgType<'tcx, Ty<'tcx>>,
 180         idx: &mut usize,
 181         dst: PlaceRef<'tcx, Self::Value>,
 182     );
 183     fn store_arg_ty(
 184         &mut self,
 185         ty: &ArgType<'tcx, Ty<'tcx>>,
 186         val: Self::Value,
 187         dst: PlaceRef<'tcx, Self::Value>,
 188     );
 189     fn memory_ty(&self, ty: &ArgType<'tcx, Ty<'tcx>>) -> Self::Type;
 190 }
 191
 192 pub trait TypeMethods<'tcx>: DerivedTypeMethods<'tcx> + LayoutTypeMethods<'tcx> {}
 193
 194 impl<T> TypeMethods<'tcx> for T where Self: DerivedTypeMethods<'tcx> + LayoutTypeMethods<'tcx> {}