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			941 lines
		
	
	
		
			36 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			941 lines
		
	
	
		
			36 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! Definition of [`CValue`] and [`CPlace`]
 | |
| 
 | |
| use crate::prelude::*;
 | |
| 
 | |
| use cranelift_codegen::ir::immediates::Offset32;
 | |
| 
 | |
| fn codegen_field<'tcx>(
 | |
|     fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|     base: Pointer,
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|     extra: Option<Value>,
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|     layout: TyAndLayout<'tcx>,
 | |
|     field: mir::Field,
 | |
| ) -> (Pointer, TyAndLayout<'tcx>) {
 | |
|     let field_offset = layout.fields.offset(field.index());
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|     let field_layout = layout.field(&*fx, field.index());
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| 
 | |
|     let simple = |fx: &mut FunctionCx<'_, '_, '_>| {
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|         (base.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap()), field_layout)
 | |
|     };
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| 
 | |
|     if let Some(extra) = extra {
 | |
|         if !field_layout.is_unsized() {
 | |
|             return simple(fx);
 | |
|         }
 | |
|         match field_layout.ty.kind() {
 | |
|             ty::Slice(..) | ty::Str | ty::Foreign(..) => simple(fx),
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|             ty::Adt(def, _) if def.repr().packed() => {
 | |
|                 assert_eq!(layout.align.abi.bytes(), 1);
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|                 simple(fx)
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|             }
 | |
|             _ => {
 | |
|                 // We have to align the offset for DST's
 | |
|                 let unaligned_offset = field_offset.bytes();
 | |
|                 let (_, unsized_align) =
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|                     crate::unsize::size_and_align_of_dst(fx, field_layout, extra);
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| 
 | |
|                 let one = fx.bcx.ins().iconst(fx.pointer_type, 1);
 | |
|                 let align_sub_1 = fx.bcx.ins().isub(unsized_align, one);
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|                 let and_lhs = fx.bcx.ins().iadd_imm(align_sub_1, unaligned_offset as i64);
 | |
|                 let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
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|                 let and_rhs = fx.bcx.ins().isub(zero, unsized_align);
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|                 let offset = fx.bcx.ins().band(and_lhs, and_rhs);
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| 
 | |
|                 (base.offset_value(fx, offset), field_layout)
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|             }
 | |
|         }
 | |
|     } else {
 | |
|         simple(fx)
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|     }
 | |
| }
 | |
| 
 | |
| fn scalar_pair_calculate_b_offset(tcx: TyCtxt<'_>, a_scalar: Scalar, b_scalar: Scalar) -> Offset32 {
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|     let b_offset = a_scalar.size(&tcx).align_to(b_scalar.align(&tcx).abi);
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|     Offset32::new(b_offset.bytes().try_into().unwrap())
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| }
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| 
 | |
| /// A read-only value
 | |
| #[derive(Debug, Copy, Clone)]
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| pub(crate) struct CValue<'tcx>(CValueInner, TyAndLayout<'tcx>);
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| 
 | |
| #[derive(Debug, Copy, Clone)]
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| enum CValueInner {
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|     ByRef(Pointer, Option<Value>),
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|     ByVal(Value),
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|     ByValPair(Value, Value),
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| }
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| 
 | |
| impl<'tcx> CValue<'tcx> {
 | |
|     pub(crate) fn by_ref(ptr: Pointer, layout: TyAndLayout<'tcx>) -> CValue<'tcx> {
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|         CValue(CValueInner::ByRef(ptr, None), layout)
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|     }
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| 
 | |
|     pub(crate) fn by_ref_unsized(
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|         ptr: Pointer,
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|         meta: Value,
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|         layout: TyAndLayout<'tcx>,
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|     ) -> CValue<'tcx> {
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|         CValue(CValueInner::ByRef(ptr, Some(meta)), layout)
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|     }
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| 
 | |
|     pub(crate) fn by_val(value: Value, layout: TyAndLayout<'tcx>) -> CValue<'tcx> {
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|         CValue(CValueInner::ByVal(value), layout)
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|     }
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| 
 | |
|     pub(crate) fn by_val_pair(
 | |
|         value: Value,
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|         extra: Value,
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|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CValue<'tcx> {
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|         CValue(CValueInner::ByValPair(value, extra), layout)
 | |
|     }
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| 
 | |
|     pub(crate) fn layout(&self) -> TyAndLayout<'tcx> {
 | |
|         self.1
 | |
|     }
 | |
| 
 | |
|     // FIXME remove
 | |
|     pub(crate) fn force_stack(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> (Pointer, Option<Value>) {
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|         let layout = self.1;
 | |
|         match self.0 {
 | |
|             CValueInner::ByRef(ptr, meta) => (ptr, meta),
 | |
|             CValueInner::ByVal(_) | CValueInner::ByValPair(_, _) => {
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|                 let cplace = CPlace::new_stack_slot(fx, layout);
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|                 cplace.write_cvalue(fx, self);
 | |
|                 (cplace.to_ptr(), None)
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|             }
 | |
|         }
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|     }
 | |
| 
 | |
|     // FIXME remove
 | |
|     // Forces the data value of a dyn* value to the stack and returns a pointer to it as well as the
 | |
|     // vtable pointer.
 | |
|     pub(crate) fn dyn_star_force_data_on_stack(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|     ) -> (Value, Value) {
 | |
|         assert!(self.1.ty.is_dyn_star());
 | |
| 
 | |
|         match self.0 {
 | |
|             CValueInner::ByRef(ptr, None) => {
 | |
|                 let (a_scalar, b_scalar) = match self.1.abi {
 | |
|                     Abi::ScalarPair(a, b) => (a, b),
 | |
|                     _ => unreachable!("dyn_star_force_data_on_stack({:?})", self),
 | |
|                 };
 | |
|                 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
 | |
|                 let clif_ty2 = scalar_to_clif_type(fx.tcx, b_scalar);
 | |
|                 let mut flags = MemFlags::new();
 | |
|                 flags.set_notrap();
 | |
|                 let vtable = ptr.offset(fx, b_offset).load(fx, clif_ty2, flags);
 | |
|                 (ptr.get_addr(fx), vtable)
 | |
|             }
 | |
|             CValueInner::ByValPair(data, vtable) => {
 | |
|                 let stack_slot = fx.bcx.create_sized_stack_slot(StackSlotData {
 | |
|                     kind: StackSlotKind::ExplicitSlot,
 | |
|                     // FIXME Don't force the size to a multiple of 16 bytes once Cranelift gets a way to
 | |
|                     // specify stack slot alignment.
 | |
|                     size: (u32::try_from(fx.target_config.pointer_type().bytes()).unwrap() + 15)
 | |
|                         / 16
 | |
|                         * 16,
 | |
|                 });
 | |
|                 let data_ptr = Pointer::stack_slot(stack_slot);
 | |
|                 let mut flags = MemFlags::new();
 | |
|                 flags.set_notrap();
 | |
|                 data_ptr.store(fx, data, flags);
 | |
| 
 | |
|                 (data_ptr.get_addr(fx), vtable)
 | |
|             }
 | |
|             CValueInner::ByRef(_, Some(_)) | CValueInner::ByVal(_) => {
 | |
|                 unreachable!("dyn_star_force_data_on_stack({:?})", self)
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn try_to_ptr(self) -> Option<(Pointer, Option<Value>)> {
 | |
|         match self.0 {
 | |
|             CValueInner::ByRef(ptr, meta) => Some((ptr, meta)),
 | |
|             CValueInner::ByVal(_) | CValueInner::ByValPair(_, _) => None,
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /// Load a value with layout.abi of scalar
 | |
|     pub(crate) fn load_scalar(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> Value {
 | |
|         let layout = self.1;
 | |
|         match self.0 {
 | |
|             CValueInner::ByRef(ptr, None) => {
 | |
|                 let clif_ty = match layout.abi {
 | |
|                     Abi::Scalar(scalar) => scalar_to_clif_type(fx.tcx, scalar),
 | |
|                     Abi::Vector { element, count } => scalar_to_clif_type(fx.tcx, element)
 | |
|                         .by(u32::try_from(count).unwrap())
 | |
|                         .unwrap(),
 | |
|                     _ => unreachable!("{:?}", layout.ty),
 | |
|                 };
 | |
|                 let mut flags = MemFlags::new();
 | |
|                 flags.set_notrap();
 | |
|                 ptr.load(fx, clif_ty, flags)
 | |
|             }
 | |
|             CValueInner::ByVal(value) => value,
 | |
|             CValueInner::ByRef(_, Some(_)) => bug!("load_scalar for unsized value not allowed"),
 | |
|             CValueInner::ByValPair(_, _) => bug!("Please use load_scalar_pair for ByValPair"),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /// Load a value pair with layout.abi of scalar pair
 | |
|     pub(crate) fn load_scalar_pair(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> (Value, Value) {
 | |
|         let layout = self.1;
 | |
|         match self.0 {
 | |
|             CValueInner::ByRef(ptr, None) => {
 | |
|                 let (a_scalar, b_scalar) = match layout.abi {
 | |
|                     Abi::ScalarPair(a, b) => (a, b),
 | |
|                     _ => unreachable!("load_scalar_pair({:?})", self),
 | |
|                 };
 | |
|                 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
 | |
|                 let clif_ty1 = scalar_to_clif_type(fx.tcx, a_scalar);
 | |
|                 let clif_ty2 = scalar_to_clif_type(fx.tcx, b_scalar);
 | |
|                 let mut flags = MemFlags::new();
 | |
|                 flags.set_notrap();
 | |
|                 let val1 = ptr.load(fx, clif_ty1, flags);
 | |
|                 let val2 = ptr.offset(fx, b_offset).load(fx, clif_ty2, flags);
 | |
|                 (val1, val2)
 | |
|             }
 | |
|             CValueInner::ByRef(_, Some(_)) => {
 | |
|                 bug!("load_scalar_pair for unsized value not allowed")
 | |
|             }
 | |
|             CValueInner::ByVal(_) => bug!("Please use load_scalar for ByVal"),
 | |
|             CValueInner::ByValPair(val1, val2) => (val1, val2),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn value_field(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         field: mir::Field,
 | |
|     ) -> CValue<'tcx> {
 | |
|         let layout = self.1;
 | |
|         match self.0 {
 | |
|             CValueInner::ByVal(val) => match layout.abi {
 | |
|                 Abi::Vector { element: _, count } => {
 | |
|                     let count = u8::try_from(count).expect("SIMD type with more than 255 lanes???");
 | |
|                     let field = u8::try_from(field.index()).unwrap();
 | |
|                     assert!(field < count);
 | |
|                     let lane = fx.bcx.ins().extractlane(val, field);
 | |
|                     let field_layout = layout.field(&*fx, usize::from(field));
 | |
|                     CValue::by_val(lane, field_layout)
 | |
|                 }
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|                 _ => unreachable!("value_field for ByVal with abi {:?}", layout.abi),
 | |
|             },
 | |
|             CValueInner::ByValPair(val1, val2) => match layout.abi {
 | |
|                 Abi::ScalarPair(_, _) => {
 | |
|                     let val = match field.as_u32() {
 | |
|                         0 => val1,
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|                         1 => val2,
 | |
|                         _ => bug!("field should be 0 or 1"),
 | |
|                     };
 | |
|                     let field_layout = layout.field(&*fx, usize::from(field));
 | |
|                     CValue::by_val(val, field_layout)
 | |
|                 }
 | |
|                 _ => unreachable!("value_field for ByValPair with abi {:?}", layout.abi),
 | |
|             },
 | |
|             CValueInner::ByRef(ptr, None) => {
 | |
|                 let (field_ptr, field_layout) = codegen_field(fx, ptr, None, layout, field);
 | |
|                 CValue::by_ref(field_ptr, field_layout)
 | |
|             }
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|             CValueInner::ByRef(_, Some(_)) => todo!(),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /// Like [`CValue::value_field`] except handling ADTs containing a single array field in a way
 | |
|     /// such that you can access individual lanes.
 | |
|     pub(crate) fn value_lane(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         lane_idx: u64,
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|     ) -> CValue<'tcx> {
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|         let layout = self.1;
 | |
|         assert!(layout.ty.is_simd());
 | |
|         let (lane_count, lane_ty) = layout.ty.simd_size_and_type(fx.tcx);
 | |
|         let lane_layout = fx.layout_of(lane_ty);
 | |
|         assert!(lane_idx < lane_count);
 | |
|         match self.0 {
 | |
|             CValueInner::ByVal(val) => match layout.abi {
 | |
|                 Abi::Vector { element: _, count: _ } => {
 | |
|                     assert!(lane_count <= u8::MAX.into(), "SIMD type with more than 255 lanes???");
 | |
|                     let lane_idx = u8::try_from(lane_idx).unwrap();
 | |
|                     let lane = fx.bcx.ins().extractlane(val, lane_idx);
 | |
|                     CValue::by_val(lane, lane_layout)
 | |
|                 }
 | |
|                 _ => unreachable!("value_lane for ByVal with abi {:?}", layout.abi),
 | |
|             },
 | |
|             CValueInner::ByValPair(_, _) => unreachable!(),
 | |
|             CValueInner::ByRef(ptr, None) => {
 | |
|                 let field_offset = lane_layout.size * lane_idx;
 | |
|                 let field_ptr = ptr.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap());
 | |
|                 CValue::by_ref(field_ptr, lane_layout)
 | |
|             }
 | |
|             CValueInner::ByRef(_, Some(_)) => unreachable!(),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn unsize_value(self, fx: &mut FunctionCx<'_, '_, 'tcx>, dest: CPlace<'tcx>) {
 | |
|         crate::unsize::coerce_unsized_into(fx, self, dest);
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn coerce_dyn_star(self, fx: &mut FunctionCx<'_, '_, 'tcx>, dest: CPlace<'tcx>) {
 | |
|         crate::unsize::coerce_dyn_star(fx, self, dest);
 | |
|     }
 | |
| 
 | |
|     /// If `ty` is signed, `const_val` must already be sign extended.
 | |
|     pub(crate) fn const_val(
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|         const_val: ty::ScalarInt,
 | |
|     ) -> CValue<'tcx> {
 | |
|         assert_eq!(const_val.size(), layout.size, "{:#?}: {:?}", const_val, layout);
 | |
|         use cranelift_codegen::ir::immediates::{Ieee32, Ieee64};
 | |
| 
 | |
|         let clif_ty = fx.clif_type(layout.ty).unwrap();
 | |
| 
 | |
|         if let ty::Bool = layout.ty.kind() {
 | |
|             assert!(
 | |
|                 const_val == ty::ScalarInt::FALSE || const_val == ty::ScalarInt::TRUE,
 | |
|                 "Invalid bool 0x{:032X}",
 | |
|                 const_val
 | |
|             );
 | |
|         }
 | |
| 
 | |
|         let val = match layout.ty.kind() {
 | |
|             ty::Uint(UintTy::U128) | ty::Int(IntTy::I128) => {
 | |
|                 let const_val = const_val.to_bits(layout.size).unwrap();
 | |
|                 let lsb = fx.bcx.ins().iconst(types::I64, const_val as u64 as i64);
 | |
|                 let msb = fx.bcx.ins().iconst(types::I64, (const_val >> 64) as u64 as i64);
 | |
|                 fx.bcx.ins().iconcat(lsb, msb)
 | |
|             }
 | |
|             ty::Bool | ty::Char | ty::Uint(_) | ty::Int(_) | ty::Ref(..) | ty::RawPtr(..) => {
 | |
|                 fx.bcx.ins().iconst(clif_ty, const_val.to_bits(layout.size).unwrap() as i64)
 | |
|             }
 | |
|             ty::Float(FloatTy::F32) => {
 | |
|                 fx.bcx.ins().f32const(Ieee32::with_bits(u32::try_from(const_val).unwrap()))
 | |
|             }
 | |
|             ty::Float(FloatTy::F64) => {
 | |
|                 fx.bcx.ins().f64const(Ieee64::with_bits(u64::try_from(const_val).unwrap()))
 | |
|             }
 | |
|             _ => panic!(
 | |
|                 "CValue::const_val for non bool/char/float/integer/pointer type {:?} is not allowed",
 | |
|                 layout.ty
 | |
|             ),
 | |
|         };
 | |
| 
 | |
|         CValue::by_val(val, layout)
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn cast_pointer_to(self, layout: TyAndLayout<'tcx>) -> Self {
 | |
|         assert!(matches!(self.layout().ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
 | |
|         assert!(matches!(layout.ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
 | |
|         assert_eq!(self.layout().abi, layout.abi);
 | |
|         CValue(self.0, layout)
 | |
|     }
 | |
| }
 | |
| 
 | |
| /// A place where you can write a value to or read a value from
 | |
| #[derive(Debug, Copy, Clone)]
 | |
| pub(crate) struct CPlace<'tcx> {
 | |
|     inner: CPlaceInner,
 | |
|     layout: TyAndLayout<'tcx>,
 | |
| }
 | |
| 
 | |
| #[derive(Debug, Copy, Clone)]
 | |
| pub(crate) enum CPlaceInner {
 | |
|     Var(Local, Variable),
 | |
|     VarPair(Local, Variable, Variable),
 | |
|     VarLane(Local, Variable, u8),
 | |
|     Addr(Pointer, Option<Value>),
 | |
| }
 | |
| 
 | |
| impl<'tcx> CPlace<'tcx> {
 | |
|     pub(crate) fn layout(&self) -> TyAndLayout<'tcx> {
 | |
|         self.layout
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn inner(&self) -> &CPlaceInner {
 | |
|         &self.inner
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn new_stack_slot(
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         assert!(!layout.is_unsized());
 | |
|         if layout.size.bytes() == 0 {
 | |
|             return CPlace {
 | |
|                 inner: CPlaceInner::Addr(Pointer::dangling(layout.align.pref), None),
 | |
|                 layout,
 | |
|             };
 | |
|         }
 | |
| 
 | |
|         if layout.size.bytes() >= u64::from(u32::MAX - 16) {
 | |
|             fx.tcx
 | |
|                 .sess
 | |
|                 .fatal(&format!("values of type {} are too big to store on the stack", layout.ty));
 | |
|         }
 | |
| 
 | |
|         let stack_slot = fx.bcx.create_sized_stack_slot(StackSlotData {
 | |
|             kind: StackSlotKind::ExplicitSlot,
 | |
|             // FIXME Don't force the size to a multiple of 16 bytes once Cranelift gets a way to
 | |
|             // specify stack slot alignment.
 | |
|             size: (u32::try_from(layout.size.bytes()).unwrap() + 15) / 16 * 16,
 | |
|         });
 | |
|         CPlace { inner: CPlaceInner::Addr(Pointer::stack_slot(stack_slot), None), layout }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn new_var(
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         local: Local,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         let var = Variable::with_u32(fx.next_ssa_var);
 | |
|         fx.next_ssa_var += 1;
 | |
|         fx.bcx.declare_var(var, fx.clif_type(layout.ty).unwrap());
 | |
|         CPlace { inner: CPlaceInner::Var(local, var), layout }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn new_var_pair(
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         local: Local,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         let var1 = Variable::with_u32(fx.next_ssa_var);
 | |
|         fx.next_ssa_var += 1;
 | |
|         let var2 = Variable::with_u32(fx.next_ssa_var);
 | |
|         fx.next_ssa_var += 1;
 | |
| 
 | |
|         let (ty1, ty2) = fx.clif_pair_type(layout.ty).unwrap();
 | |
|         fx.bcx.declare_var(var1, ty1);
 | |
|         fx.bcx.declare_var(var2, ty2);
 | |
|         CPlace { inner: CPlaceInner::VarPair(local, var1, var2), layout }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn for_ptr(ptr: Pointer, layout: TyAndLayout<'tcx>) -> CPlace<'tcx> {
 | |
|         CPlace { inner: CPlaceInner::Addr(ptr, None), layout }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn for_ptr_with_extra(
 | |
|         ptr: Pointer,
 | |
|         extra: Value,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         CPlace { inner: CPlaceInner::Addr(ptr, Some(extra)), layout }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn to_cvalue(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> CValue<'tcx> {
 | |
|         let layout = self.layout();
 | |
|         match self.inner {
 | |
|             CPlaceInner::Var(_local, var) => {
 | |
|                 let val = fx.bcx.use_var(var);
 | |
|                 //fx.bcx.set_val_label(val, cranelift_codegen::ir::ValueLabel::new(var.index()));
 | |
|                 CValue::by_val(val, layout)
 | |
|             }
 | |
|             CPlaceInner::VarPair(_local, var1, var2) => {
 | |
|                 let val1 = fx.bcx.use_var(var1);
 | |
|                 //fx.bcx.set_val_label(val1, cranelift_codegen::ir::ValueLabel::new(var1.index()));
 | |
|                 let val2 = fx.bcx.use_var(var2);
 | |
|                 //fx.bcx.set_val_label(val2, cranelift_codegen::ir::ValueLabel::new(var2.index()));
 | |
|                 CValue::by_val_pair(val1, val2, layout)
 | |
|             }
 | |
|             CPlaceInner::VarLane(_local, var, lane) => {
 | |
|                 let val = fx.bcx.use_var(var);
 | |
|                 //fx.bcx.set_val_label(val, cranelift_codegen::ir::ValueLabel::new(var.index()));
 | |
|                 let val = fx.bcx.ins().extractlane(val, lane);
 | |
|                 CValue::by_val(val, layout)
 | |
|             }
 | |
|             CPlaceInner::Addr(ptr, extra) => {
 | |
|                 if let Some(extra) = extra {
 | |
|                     CValue::by_ref_unsized(ptr, extra, layout)
 | |
|                 } else {
 | |
|                     CValue::by_ref(ptr, layout)
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn to_ptr(self) -> Pointer {
 | |
|         match self.to_ptr_maybe_unsized() {
 | |
|             (ptr, None) => ptr,
 | |
|             (_, Some(_)) => bug!("Expected sized cplace, found {:?}", self),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn to_ptr_maybe_unsized(self) -> (Pointer, Option<Value>) {
 | |
|         match self.inner {
 | |
|             CPlaceInner::Addr(ptr, extra) => (ptr, extra),
 | |
|             CPlaceInner::Var(_, _)
 | |
|             | CPlaceInner::VarPair(_, _, _)
 | |
|             | CPlaceInner::VarLane(_, _, _) => bug!("Expected CPlace::Addr, found {:?}", self),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn write_cvalue(self, fx: &mut FunctionCx<'_, '_, 'tcx>, from: CValue<'tcx>) {
 | |
|         assert_assignable(fx, from.layout().ty, self.layout().ty, 16);
 | |
| 
 | |
|         self.write_cvalue_maybe_transmute(fx, from, "write_cvalue");
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn write_cvalue_transmute(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         from: CValue<'tcx>,
 | |
|     ) {
 | |
|         self.write_cvalue_maybe_transmute(fx, from, "write_cvalue_transmute");
 | |
|     }
 | |
| 
 | |
|     fn write_cvalue_maybe_transmute(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         from: CValue<'tcx>,
 | |
|         method: &'static str,
 | |
|     ) {
 | |
|         fn transmute_value<'tcx>(
 | |
|             fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|             var: Variable,
 | |
|             data: Value,
 | |
|             dst_ty: Type,
 | |
|         ) {
 | |
|             let src_ty = fx.bcx.func.dfg.value_type(data);
 | |
|             assert_eq!(
 | |
|                 src_ty.bytes(),
 | |
|                 dst_ty.bytes(),
 | |
|                 "write_cvalue_transmute: {:?} -> {:?}",
 | |
|                 src_ty,
 | |
|                 dst_ty,
 | |
|             );
 | |
|             let data = match (src_ty, dst_ty) {
 | |
|                 (_, _) if src_ty == dst_ty => data,
 | |
| 
 | |
|                 // This is a `write_cvalue_transmute`.
 | |
|                 (types::I32, types::F32)
 | |
|                 | (types::F32, types::I32)
 | |
|                 | (types::I64, types::F64)
 | |
|                 | (types::F64, types::I64) => fx.bcx.ins().bitcast(dst_ty, data),
 | |
|                 _ if src_ty.is_vector() && dst_ty.is_vector() => {
 | |
|                     fx.bcx.ins().raw_bitcast(dst_ty, data)
 | |
|                 }
 | |
|                 _ if src_ty.is_vector() || dst_ty.is_vector() => {
 | |
|                     // FIXME do something more efficient for transmutes between vectors and integers.
 | |
|                     let stack_slot = fx.bcx.create_sized_stack_slot(StackSlotData {
 | |
|                         kind: StackSlotKind::ExplicitSlot,
 | |
|                         // FIXME Don't force the size to a multiple of 16 bytes once Cranelift gets a way to
 | |
|                         // specify stack slot alignment.
 | |
|                         size: (src_ty.bytes() + 15) / 16 * 16,
 | |
|                     });
 | |
|                     let ptr = Pointer::stack_slot(stack_slot);
 | |
|                     ptr.store(fx, data, MemFlags::trusted());
 | |
|                     ptr.load(fx, dst_ty, MemFlags::trusted())
 | |
|                 }
 | |
| 
 | |
|                 // `CValue`s should never contain SSA-only types, so if you ended
 | |
|                 // up here having seen an error like `B1 -> I8`, then before
 | |
|                 // calling `write_cvalue` you need to add a `bint` instruction.
 | |
|                 _ => unreachable!("write_cvalue_transmute: {:?} -> {:?}", src_ty, dst_ty),
 | |
|             };
 | |
|             //fx.bcx.set_val_label(data, cranelift_codegen::ir::ValueLabel::new(var.index()));
 | |
|             fx.bcx.def_var(var, data);
 | |
|         }
 | |
| 
 | |
|         assert_eq!(self.layout().size, from.layout().size);
 | |
| 
 | |
|         if fx.clif_comments.enabled() {
 | |
|             use cranelift_codegen::cursor::{Cursor, CursorPosition};
 | |
|             let cur_block = match fx.bcx.cursor().position() {
 | |
|                 CursorPosition::After(block) => block,
 | |
|                 _ => unreachable!(),
 | |
|             };
 | |
|             fx.add_comment(
 | |
|                 fx.bcx.func.layout.last_inst(cur_block).unwrap(),
 | |
|                 format!(
 | |
|                     "{}: {:?}: {:?} <- {:?}: {:?}",
 | |
|                     method,
 | |
|                     self.inner(),
 | |
|                     self.layout().ty,
 | |
|                     from.0,
 | |
|                     from.layout().ty
 | |
|                 ),
 | |
|             );
 | |
|         }
 | |
| 
 | |
|         let dst_layout = self.layout();
 | |
|         let to_ptr = match self.inner {
 | |
|             CPlaceInner::Var(_local, var) => {
 | |
|                 if let ty::Array(element, len) = dst_layout.ty.kind() {
 | |
|                     // Can only happen for vector types
 | |
|                     let len =
 | |
|                         u32::try_from(len.eval_usize(fx.tcx, ParamEnv::reveal_all())).unwrap();
 | |
|                     let vector_ty = fx.clif_type(*element).unwrap().by(len).unwrap();
 | |
| 
 | |
|                     let data = match from.0 {
 | |
|                         CValueInner::ByRef(ptr, None) => {
 | |
|                             let mut flags = MemFlags::new();
 | |
|                             flags.set_notrap();
 | |
|                             ptr.load(fx, vector_ty, flags)
 | |
|                         }
 | |
|                         CValueInner::ByVal(_)
 | |
|                         | CValueInner::ByValPair(_, _)
 | |
|                         | CValueInner::ByRef(_, Some(_)) => bug!("array should be ByRef"),
 | |
|                     };
 | |
| 
 | |
|                     fx.bcx.def_var(var, data);
 | |
|                     return;
 | |
|                 }
 | |
|                 let data = CValue(from.0, dst_layout).load_scalar(fx);
 | |
|                 let dst_ty = fx.clif_type(self.layout().ty).unwrap();
 | |
|                 transmute_value(fx, var, data, dst_ty);
 | |
|                 return;
 | |
|             }
 | |
|             CPlaceInner::VarPair(_local, var1, var2) => {
 | |
|                 let (data1, data2) = CValue(from.0, dst_layout).load_scalar_pair(fx);
 | |
|                 let (dst_ty1, dst_ty2) = fx.clif_pair_type(self.layout().ty).unwrap();
 | |
|                 transmute_value(fx, var1, data1, dst_ty1);
 | |
|                 transmute_value(fx, var2, data2, dst_ty2);
 | |
|                 return;
 | |
|             }
 | |
|             CPlaceInner::VarLane(_local, var, lane) => {
 | |
|                 let data = from.load_scalar(fx);
 | |
| 
 | |
|                 // First get the old vector
 | |
|                 let vector = fx.bcx.use_var(var);
 | |
|                 //fx.bcx.set_val_label(vector, cranelift_codegen::ir::ValueLabel::new(var.index()));
 | |
| 
 | |
|                 // Next insert the written lane into the vector
 | |
|                 let vector = fx.bcx.ins().insertlane(vector, data, lane);
 | |
| 
 | |
|                 // Finally write the new vector
 | |
|                 //fx.bcx.set_val_label(vector, cranelift_codegen::ir::ValueLabel::new(var.index()));
 | |
|                 fx.bcx.def_var(var, vector);
 | |
| 
 | |
|                 return;
 | |
|             }
 | |
|             CPlaceInner::Addr(ptr, None) => {
 | |
|                 if dst_layout.size == Size::ZERO || dst_layout.abi == Abi::Uninhabited {
 | |
|                     return;
 | |
|                 }
 | |
|                 ptr
 | |
|             }
 | |
|             CPlaceInner::Addr(_, Some(_)) => bug!("Can't write value to unsized place {:?}", self),
 | |
|         };
 | |
| 
 | |
|         let mut flags = MemFlags::new();
 | |
|         flags.set_notrap();
 | |
|         match from.layout().abi {
 | |
|             // FIXME make Abi::Vector work too
 | |
|             Abi::Scalar(_) => {
 | |
|                 let val = from.load_scalar(fx);
 | |
|                 to_ptr.store(fx, val, flags);
 | |
|                 return;
 | |
|             }
 | |
|             Abi::ScalarPair(a_scalar, b_scalar) => {
 | |
|                 let (value, extra) = from.load_scalar_pair(fx);
 | |
|                 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
 | |
|                 to_ptr.store(fx, value, flags);
 | |
|                 to_ptr.offset(fx, b_offset).store(fx, extra, flags);
 | |
|                 return;
 | |
|             }
 | |
|             _ => {}
 | |
|         }
 | |
| 
 | |
|         match from.0 {
 | |
|             CValueInner::ByVal(val) => {
 | |
|                 to_ptr.store(fx, val, flags);
 | |
|             }
 | |
|             CValueInner::ByValPair(_, _) => {
 | |
|                 bug!("Non ScalarPair abi {:?} for ByValPair CValue", dst_layout.abi);
 | |
|             }
 | |
|             CValueInner::ByRef(from_ptr, None) => {
 | |
|                 let from_addr = from_ptr.get_addr(fx);
 | |
|                 let to_addr = to_ptr.get_addr(fx);
 | |
|                 let src_layout = from.1;
 | |
|                 let size = dst_layout.size.bytes();
 | |
|                 let src_align = src_layout.align.abi.bytes() as u8;
 | |
|                 let dst_align = dst_layout.align.abi.bytes() as u8;
 | |
|                 fx.bcx.emit_small_memory_copy(
 | |
|                     fx.target_config,
 | |
|                     to_addr,
 | |
|                     from_addr,
 | |
|                     size,
 | |
|                     dst_align,
 | |
|                     src_align,
 | |
|                     true,
 | |
|                     flags,
 | |
|                 );
 | |
|             }
 | |
|             CValueInner::ByRef(_, Some(_)) => todo!(),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn place_opaque_cast(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         ty: Ty<'tcx>,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         CPlace { inner: self.inner, layout: fx.layout_of(ty) }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn place_field(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         field: mir::Field,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         let layout = self.layout();
 | |
| 
 | |
|         match self.inner {
 | |
|             CPlaceInner::Var(local, var) => match layout.ty.kind() {
 | |
|                 ty::Array(_, _) => {
 | |
|                     // Can only happen for vector types
 | |
|                     return CPlace {
 | |
|                         inner: CPlaceInner::VarLane(local, var, field.as_u32().try_into().unwrap()),
 | |
|                         layout: layout.field(fx, field.as_u32().try_into().unwrap()),
 | |
|                     };
 | |
|                 }
 | |
|                 ty::Adt(adt_def, substs) if layout.ty.is_simd() => {
 | |
|                     let f0_ty = adt_def.non_enum_variant().fields[0].ty(fx.tcx, substs);
 | |
| 
 | |
|                     match f0_ty.kind() {
 | |
|                         ty::Array(_, _) => {
 | |
|                             assert_eq!(field.as_u32(), 0);
 | |
|                             return CPlace {
 | |
|                                 inner: CPlaceInner::Var(local, var),
 | |
|                                 layout: layout.field(fx, field.as_u32().try_into().unwrap()),
 | |
|                             };
 | |
|                         }
 | |
|                         _ => {
 | |
|                             return CPlace {
 | |
|                                 inner: CPlaceInner::VarLane(
 | |
|                                     local,
 | |
|                                     var,
 | |
|                                     field.as_u32().try_into().unwrap(),
 | |
|                                 ),
 | |
|                                 layout: layout.field(fx, field.as_u32().try_into().unwrap()),
 | |
|                             };
 | |
|                         }
 | |
|                     }
 | |
|                 }
 | |
|                 _ => {}
 | |
|             },
 | |
|             CPlaceInner::VarPair(local, var1, var2) => {
 | |
|                 let layout = layout.field(&*fx, field.index());
 | |
| 
 | |
|                 match field.as_u32() {
 | |
|                     0 => return CPlace { inner: CPlaceInner::Var(local, var1), layout },
 | |
|                     1 => return CPlace { inner: CPlaceInner::Var(local, var2), layout },
 | |
|                     _ => unreachable!("field should be 0 or 1"),
 | |
|                 }
 | |
|             }
 | |
|             _ => {}
 | |
|         }
 | |
| 
 | |
|         let (base, extra) = self.to_ptr_maybe_unsized();
 | |
| 
 | |
|         let (field_ptr, field_layout) = codegen_field(fx, base, extra, layout, field);
 | |
|         if field_layout.is_unsized() {
 | |
|             if let ty::Foreign(_) = field_layout.ty.kind() {
 | |
|                 assert!(extra.is_none());
 | |
|                 CPlace::for_ptr(field_ptr, field_layout)
 | |
|             } else {
 | |
|                 CPlace::for_ptr_with_extra(field_ptr, extra.unwrap(), field_layout)
 | |
|             }
 | |
|         } else {
 | |
|             CPlace::for_ptr(field_ptr, field_layout)
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /// Like [`CPlace::place_field`] except handling ADTs containing a single array field in a way
 | |
|     /// such that you can access individual lanes.
 | |
|     pub(crate) fn place_lane(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         lane_idx: u64,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         let layout = self.layout();
 | |
|         assert!(layout.ty.is_simd());
 | |
|         let (lane_count, lane_ty) = layout.ty.simd_size_and_type(fx.tcx);
 | |
|         let lane_layout = fx.layout_of(lane_ty);
 | |
|         assert!(lane_idx < lane_count);
 | |
| 
 | |
|         match self.inner {
 | |
|             CPlaceInner::Var(local, var) => {
 | |
|                 assert!(matches!(layout.abi, Abi::Vector { .. }));
 | |
|                 CPlace {
 | |
|                     inner: CPlaceInner::VarLane(local, var, lane_idx.try_into().unwrap()),
 | |
|                     layout: lane_layout,
 | |
|                 }
 | |
|             }
 | |
|             CPlaceInner::VarPair(_, _, _) => unreachable!(),
 | |
|             CPlaceInner::VarLane(_, _, _) => unreachable!(),
 | |
|             CPlaceInner::Addr(ptr, None) => {
 | |
|                 let field_offset = lane_layout.size * lane_idx;
 | |
|                 let field_ptr = ptr.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap());
 | |
|                 CPlace::for_ptr(field_ptr, lane_layout)
 | |
|             }
 | |
|             CPlaceInner::Addr(_, Some(_)) => unreachable!(),
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn place_index(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         index: Value,
 | |
|     ) -> CPlace<'tcx> {
 | |
|         let (elem_layout, ptr) = match self.layout().ty.kind() {
 | |
|             ty::Array(elem_ty, _) => (fx.layout_of(*elem_ty), self.to_ptr()),
 | |
|             ty::Slice(elem_ty) => (fx.layout_of(*elem_ty), self.to_ptr_maybe_unsized().0),
 | |
|             _ => bug!("place_index({:?})", self.layout().ty),
 | |
|         };
 | |
| 
 | |
|         let offset = fx.bcx.ins().imul_imm(index, elem_layout.size.bytes() as i64);
 | |
| 
 | |
|         CPlace::for_ptr(ptr.offset_value(fx, offset), elem_layout)
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn place_deref(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> CPlace<'tcx> {
 | |
|         let inner_layout = fx.layout_of(self.layout().ty.builtin_deref(true).unwrap().ty);
 | |
|         if has_ptr_meta(fx.tcx, inner_layout.ty) {
 | |
|             let (addr, extra) = self.to_cvalue(fx).load_scalar_pair(fx);
 | |
|             CPlace::for_ptr_with_extra(Pointer::new(addr), extra, inner_layout)
 | |
|         } else {
 | |
|             CPlace::for_ptr(Pointer::new(self.to_cvalue(fx).load_scalar(fx)), inner_layout)
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn place_ref(
 | |
|         self,
 | |
|         fx: &mut FunctionCx<'_, '_, 'tcx>,
 | |
|         layout: TyAndLayout<'tcx>,
 | |
|     ) -> CValue<'tcx> {
 | |
|         if has_ptr_meta(fx.tcx, self.layout().ty) {
 | |
|             let (ptr, extra) = self.to_ptr_maybe_unsized();
 | |
|             CValue::by_val_pair(
 | |
|                 ptr.get_addr(fx),
 | |
|                 extra.expect("unsized type without metadata"),
 | |
|                 layout,
 | |
|             )
 | |
|         } else {
 | |
|             CValue::by_val(self.to_ptr().get_addr(fx), layout)
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     pub(crate) fn downcast_variant(
 | |
|         self,
 | |
|         fx: &FunctionCx<'_, '_, 'tcx>,
 | |
|         variant: VariantIdx,
 | |
|     ) -> Self {
 | |
|         assert!(!self.layout().is_unsized());
 | |
|         let layout = self.layout().for_variant(fx, variant);
 | |
|         CPlace { inner: self.inner, layout }
 | |
|     }
 | |
| }
 | |
| 
 | |
| #[track_caller]
 | |
| pub(crate) fn assert_assignable<'tcx>(
 | |
|     fx: &FunctionCx<'_, '_, 'tcx>,
 | |
|     from_ty: Ty<'tcx>,
 | |
|     to_ty: Ty<'tcx>,
 | |
|     limit: usize,
 | |
| ) {
 | |
|     if limit == 0 {
 | |
|         // assert_assignable exists solely to catch bugs in cg_clif. it isn't necessary for
 | |
|         // soundness. don't attempt to check deep types to avoid exponential behavior in certain
 | |
|         // cases.
 | |
|         return;
 | |
|     }
 | |
|     match (from_ty.kind(), to_ty.kind()) {
 | |
|         (ty::Ref(_, a, _), ty::Ref(_, b, _))
 | |
|         | (
 | |
|             ty::RawPtr(TypeAndMut { ty: a, mutbl: _ }),
 | |
|             ty::RawPtr(TypeAndMut { ty: b, mutbl: _ }),
 | |
|         ) => {
 | |
|             assert_assignable(fx, *a, *b, limit - 1);
 | |
|         }
 | |
|         (ty::Ref(_, a, _), ty::RawPtr(TypeAndMut { ty: b, mutbl: _ }))
 | |
|         | (ty::RawPtr(TypeAndMut { ty: a, mutbl: _ }), ty::Ref(_, b, _)) => {
 | |
|             assert_assignable(fx, *a, *b, limit - 1);
 | |
|         }
 | |
|         (ty::FnPtr(_), ty::FnPtr(_)) => {
 | |
|             let from_sig = fx.tcx.normalize_erasing_late_bound_regions(
 | |
|                 ParamEnv::reveal_all(),
 | |
|                 from_ty.fn_sig(fx.tcx),
 | |
|             );
 | |
|             let to_sig = fx
 | |
|                 .tcx
 | |
|                 .normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to_ty.fn_sig(fx.tcx));
 | |
|             assert_eq!(
 | |
|                 from_sig, to_sig,
 | |
|                 "Can't write fn ptr with incompatible sig {:?} to place with sig {:?}\n\n{:#?}",
 | |
|                 from_sig, to_sig, fx,
 | |
|             );
 | |
|             // fn(&T) -> for<'l> fn(&'l T) is allowed
 | |
|         }
 | |
|         (&ty::Dynamic(from_traits, _, _from_kind), &ty::Dynamic(to_traits, _, _to_kind)) => {
 | |
|             // FIXME(dyn-star): Do the right thing with DynKinds
 | |
|             for (from, to) in from_traits.iter().zip(to_traits) {
 | |
|                 let from =
 | |
|                     fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), from);
 | |
|                 let to = fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to);
 | |
|                 assert_eq!(
 | |
|                     from, to,
 | |
|                     "Can't write trait object of incompatible traits {:?} to place with traits {:?}\n\n{:#?}",
 | |
|                     from_traits, to_traits, fx,
 | |
|                 );
 | |
|             }
 | |
|             // dyn for<'r> Trait<'r> -> dyn Trait<'_> is allowed
 | |
|         }
 | |
|         (&ty::Tuple(types_a), &ty::Tuple(types_b)) => {
 | |
|             let mut types_a = types_a.iter();
 | |
|             let mut types_b = types_b.iter();
 | |
|             loop {
 | |
|                 match (types_a.next(), types_b.next()) {
 | |
|                     (Some(a), Some(b)) => assert_assignable(fx, a, b, limit - 1),
 | |
|                     (None, None) => return,
 | |
|                     (Some(_), None) | (None, Some(_)) => panic!("{:#?}/{:#?}", from_ty, to_ty),
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         (&ty::Adt(adt_def_a, substs_a), &ty::Adt(adt_def_b, substs_b))
 | |
|             if adt_def_a.did() == adt_def_b.did() =>
 | |
|         {
 | |
|             let mut types_a = substs_a.types();
 | |
|             let mut types_b = substs_b.types();
 | |
|             loop {
 | |
|                 match (types_a.next(), types_b.next()) {
 | |
|                     (Some(a), Some(b)) => assert_assignable(fx, a, b, limit - 1),
 | |
|                     (None, None) => return,
 | |
|                     (Some(_), None) | (None, Some(_)) => panic!("{:#?}/{:#?}", from_ty, to_ty),
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         (ty::Array(a, _), ty::Array(b, _)) => assert_assignable(fx, *a, *b, limit - 1),
 | |
|         (&ty::Closure(def_id_a, substs_a), &ty::Closure(def_id_b, substs_b))
 | |
|             if def_id_a == def_id_b =>
 | |
|         {
 | |
|             let mut types_a = substs_a.types();
 | |
|             let mut types_b = substs_b.types();
 | |
|             loop {
 | |
|                 match (types_a.next(), types_b.next()) {
 | |
|                     (Some(a), Some(b)) => assert_assignable(fx, a, b, limit - 1),
 | |
|                     (None, None) => return,
 | |
|                     (Some(_), None) | (None, Some(_)) => panic!("{:#?}/{:#?}", from_ty, to_ty),
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         (ty::Param(_), _) | (_, ty::Param(_)) if fx.tcx.sess.opts.unstable_opts.polymorphize => {
 | |
|             // No way to check if it is correct or not with polymorphization enabled
 | |
|         }
 | |
|         _ => {
 | |
|             assert_eq!(
 | |
|                 from_ty,
 | |
|                 to_ty,
 | |
|                 "Can't write value with incompatible type {:?} to place with type {:?}\n\n{:#?}",
 | |
|                 from_ty.kind(),
 | |
|                 to_ty.kind(),
 | |
|                 fx,
 | |
|             );
 | |
|         }
 | |
|     }
 | |
| }
 | 
