| //! Intrinsics and other functions that the interpreter executes without | |
| //! looking at their MIR. Intrinsics/functions supported here are shared by CTFE | |
| //! and miri. | |
| mod atomic; | |
| mod simd; | |
| use std::assert_matches; | |
| use rustc_abi::{FieldIdx, HasDataLayout, Size, VariantIdx}; | |
| use rustc_apfloat::ieee::{Double, Half, Quad, Single}; | |
| use rustc_ast::{IntTy, UintTy}; | |
| use rustc_middle::mir::interpret::{CTFE_ALLOC_SALT, read_target_uint, write_target_uint}; | |
| use rustc_middle::mir::{self, BinOp, ConstValue, NonDivergingIntrinsic}; | |
| use rustc_middle::ty::layout::TyAndLayout; | |
| use rustc_middle::ty::{FloatTy, Ty, TyCtxt, TypeVisitableExt}; | |
| use rustc_middle::{bug, span_bug, ty}; | |
| use rustc_span::{Symbol, sym}; | |
| use tracing::trace; | |
| use super::memory::MemoryKind; | |
| use super::util::ensure_monomorphic_enough; | |
| use super::{ | |
| AllocId, AtomicRmwOp, CheckInAllocMsg, ImmTy, Immediate, InterpCx, InterpResult, Machine, OpTy, | |
| PlaceTy, Pointer, PointerArithmetic, Projectable, Provenance, Scalar, err_ub_format, | |
| err_unsup_format, interp_ok, throw_inval, throw_ub, throw_ub_format, | |
| }; | |
| use crate::interpret::{MPlaceTy, Writeable}; | |
| #[derive(Copy, Clone, Debug, PartialEq, Eq)] | |
| enum MulAddType { | |
| /// Used with `fma` and `simd_fma`, always uses fused-multiply-add | |
| Fused, | |
| /// Used with `fmuladd` and `simd_relaxed_fma`, nondeterministically determines whether to use | |
| /// fma or simple multiply-add | |
| Nondeterministic, | |
| } | |
| #[derive(Copy, Clone)] | |
| pub(crate) enum MinMax { | |
| /// The IEEE-2019 `minimum` operation - see `f32::minimum` etc. | |
| /// In particular, `-0.0` is considered smaller than `+0.0` and | |
| /// if either input is NaN, the result is NaN. | |
| Minimum, | |
| /// The IEEE-2019 `minimumNumber` operation but with non-deterministic signed zero handling | |
| /// (like in IEEE-2008 `minNum`) - see `f32::min` etc. | |
| /// In particular, if the inputs are `-0.0` and `+0.0`, the result is non-deterministic, | |
| /// and if one argument is NaN (quiet or signaling), the other one is returned. | |
| MinimumNumberNsz, | |
| /// The IEEE-2019 `maximum` operation - see `f32::maximum` etc. | |
| /// In particular, `-0.0` is considered smaller than `+0.0` and | |
| /// if either input is NaN, the result is NaN. | |
| Maximum, | |
| /// The IEEE-2019 `maximumNumber` operation but with non-deterministic signed zero handling | |
| /// (like in IEEE-2008 `maxNum`) - see `f32::max` etc. | |
| /// In particular, if the inputs are `-0.0` and `+0.0`, the result is non-deterministic, | |
| /// and if one argument is NaN (quiet or signaling), the other one is returned. | |
| MaximumNumberNsz, | |
| } | |
| /// Whether two types `T` and `U` are compatible when a value of type `T` is passed as a c-variadic | |
| /// argument and read as a value of type `U`. | |
| enum VarArgCompatible { | |
| /// `T` and `U` are compatible, e.g. | |
| /// | |
| /// - They're the same type. | |
| /// - One is `usize`/`isize`, the other an integer type of the same width | |
| /// and sign on the current target. | |
| /// - They are compatible pointer types (see the exact rules below). | |
| Compatible, | |
| /// `T` and `U` are definitely not compatible. | |
| Incompatible, | |
| /// `T` and `U` are corresponding signed and unsigned integer types. | |
| CastIntTo { source_is_signed: bool }, | |
| } | |
| /// Directly returns an `Allocation` containing an absolute path representation of the given type. | |
| pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> (AllocId, u64) { | |
| let path = crate::util::type_name(tcx, ty); | |
| let bytes = path.into_bytes(); | |
| let len = bytes.len().try_into().unwrap(); | |
| (tcx.allocate_bytes_dedup(bytes, CTFE_ALLOC_SALT), len) | |
| } | |
| impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { | |
| /// Generates a value of `TypeId` for `ty` in-place. | |
| pub(crate) fn write_type_id( | |
| &mut self, | |
| ty: Ty<'tcx>, | |
| dest: &impl Writeable<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, ()> { | |
| debug_assert!( | |
| !ty.has_erasable_regions(), | |
| "type {ty:?} has regions that need erasing before writing a TypeId", | |
| ); | |
| let tcx = self.tcx; | |
| let type_id_hash = tcx.type_id_hash(ty).as_u128(); | |
| let op = self.const_val_to_op( | |
| ConstValue::Scalar(Scalar::from_u128(type_id_hash)), | |
| tcx.types.u128, | |
| None, | |
| )?; | |
| self.copy_op_allow_transmute(&op, dest)?; | |
| // Give the each pointer-sized chunk provenance that knows about the type id. | |
| // Here we rely on `TypeId` being a newtype around an array of pointers, so we | |
| // first project to its only field and then the array elements. | |
| let alloc_id = tcx.reserve_and_set_type_id_alloc(ty); | |
| let arr = self.project_field(dest, FieldIdx::ZERO)?; | |
| let mut elem_iter = self.project_array_fields(&arr)?; | |
| while let Some((_, elem)) = elem_iter.next(self)? { | |
| // Decorate this part of the hash with provenance; leave the integer part unchanged. | |
| let hash_fragment = self.read_scalar(&elem)?.to_target_usize(&tcx)?; | |
| let ptr = Pointer::new(alloc_id.into(), Size::from_bytes(hash_fragment)); | |
| let ptr = self.global_root_pointer(ptr)?; | |
| let val = Scalar::from_pointer(ptr, &tcx); | |
| self.write_scalar(val, &elem)?; | |
| } | |
| interp_ok(()) | |
| } | |
| /// Read a value of type `TypeId`, returning the type it represents. | |
| pub(crate) fn read_type_id( | |
| &self, | |
| op: &OpTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, Ty<'tcx>> { | |
| // `TypeId` is a newtype around an array of pointers. All pointers must have the same | |
| // provenance, and that provenance represents the type. | |
| let ptr_size = self.pointer_size().bytes_usize(); | |
| let arr = self.project_field(op, FieldIdx::ZERO)?; | |
| let mut ty_and_hash = None; | |
| let mut elem_iter = self.project_array_fields(&arr)?; | |
| while let Some((idx, elem)) = elem_iter.next(self)? { | |
| let elem = self.read_pointer(&elem)?; | |
| let (elem_ty, elem_hash) = self.get_ptr_type_id(elem)?; | |
| // If this is the first element, remember the type and its hash. | |
| // If this is not the first element, ensure it is consistent with the previous ones. | |
| let full_hash = match ty_and_hash { | |
| None => { | |
| let hash = self.tcx.type_id_hash(elem_ty).as_u128(); | |
| let mut hash_bytes = [0u8; 16]; | |
| write_target_uint(self.data_layout().endian, &mut hash_bytes, hash).unwrap(); | |
| ty_and_hash = Some((elem_ty, hash_bytes)); | |
| hash_bytes | |
| } | |
| Some((ty, hash_bytes)) => { | |
| if ty != elem_ty { | |
| throw_ub_format!( | |
| "invalid `TypeId` value: not all bytes carry the same type id metadata" | |
| ); | |
| } | |
| hash_bytes | |
| } | |
| }; | |
| // Ensure the elem_hash matches the corresponding part of the full hash. | |
| let hash_frag = &full_hash[(idx as usize) * ptr_size..][..ptr_size]; | |
| if read_target_uint(self.data_layout().endian, hash_frag).unwrap() != elem_hash.into() { | |
| throw_ub_format!( | |
| "invalid `TypeId` value: the hash does not match the type id metadata" | |
| ); | |
| } | |
| } | |
| interp_ok(ty_and_hash.unwrap().0) | |
| } | |
| /// Returns `true` if emulation happened. | |
| /// Here we implement the intrinsics that are common to all Miri instances; individual machines can add their own | |
| /// intrinsic handling. | |
| pub fn eval_intrinsic( | |
| &mut self, | |
| instance: ty::Instance<'tcx>, | |
| args: &[OpTy<'tcx, M::Provenance>], | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| ret: Option<mir::BasicBlock>, | |
| ) -> InterpResult<'tcx, bool> { | |
| let instance_args = instance.args; | |
| let intrinsic_name = self.tcx.item_name(instance.def_id()); | |
| if intrinsic_name.as_str().starts_with("atomic_") { | |
| return self.eval_atomic_intrinsic(intrinsic_name, instance_args, args, dest, ret); | |
| } | |
| if intrinsic_name.as_str().starts_with("simd_") { | |
| return self.eval_simd_intrinsic(intrinsic_name, instance_args, args, dest, ret); | |
| } | |
| let tcx = self.tcx.tcx; | |
| match intrinsic_name { | |
| sym::type_name => { | |
| let tp_ty = instance.args.type_at(0); | |
| ensure_monomorphic_enough(tp_ty)?; | |
| let (alloc_id, meta) = alloc_type_name(tcx, tp_ty); | |
| let val = ConstValue::Slice { alloc_id, meta }; | |
| let val = self.const_val_to_op(val, dest.layout.ty, Some(dest.layout))?; | |
| self.copy_op(&val, dest)?; | |
| } | |
| sym::needs_drop => { | |
| let tp_ty = instance.args.type_at(0); | |
| ensure_monomorphic_enough(tp_ty)?; | |
| let val = ConstValue::from_bool(tp_ty.needs_drop(tcx, self.typing_env)); | |
| let val = self.const_val_to_op(val, tcx.types.bool, Some(dest.layout))?; | |
| self.copy_op(&val, dest)?; | |
| } | |
| sym::type_id => { | |
| let tp_ty = instance.args.type_at(0); | |
| ensure_monomorphic_enough(tp_ty)?; | |
| self.write_type_id(tp_ty, dest)?; | |
| } | |
| sym::type_id_eq => { | |
| let a_ty = self.read_type_id(&args[0])?; | |
| let b_ty = self.read_type_id(&args[1])?; | |
| self.write_scalar(Scalar::from_bool(a_ty == b_ty), dest)?; | |
| } | |
| sym::size_of => { | |
| let tp_ty = instance.args.type_at(0); | |
| let layout = self.layout_of(tp_ty)?; | |
| if !layout.is_sized() { | |
| span_bug!(self.cur_span(), "unsized type for `size_of`"); | |
| } | |
| let val = layout.size.bytes(); | |
| self.write_scalar(Scalar::from_target_usize(val, self), dest)?; | |
| } | |
| sym::align_of => { | |
| let tp_ty = instance.args.type_at(0); | |
| let layout = self.layout_of(tp_ty)?; | |
| if !layout.is_sized() { | |
| span_bug!(self.cur_span(), "unsized type for `align_of`"); | |
| } | |
| let val = layout.align.bytes(); | |
| self.write_scalar(Scalar::from_target_usize(val, self), dest)?; | |
| } | |
| sym::offset_of => { | |
| let tp_ty = instance.args.type_at(0); | |
| let variant = self.read_scalar(&args[0])?.to_u32()?; | |
| let field = self.read_scalar(&args[1])?.to_u32()? as usize; | |
| let layout = self.layout_of(tp_ty)?; | |
| let cx = ty::layout::LayoutCx::new(*self.tcx, self.typing_env); | |
| let layout = layout.for_variant(&cx, VariantIdx::from_u32(variant)); | |
| let offset = layout.fields.offset(field).bytes(); | |
| self.write_scalar(Scalar::from_target_usize(offset, self), dest)?; | |
| } | |
| sym::variant_count => { | |
| let tp_ty = instance.args.type_at(0); | |
| let ty = match tp_ty.kind() { | |
| // Pattern types have the same number of variants as their base type. | |
| // Even if we restrict e.g. which variants are valid, the variants are essentially just uninhabited. | |
| // And `Result<(), !>` still has two variants according to `variant_count`. | |
| ty::Pat(base, _) => *base, | |
| _ => tp_ty, | |
| }; | |
| let val = match ty.kind() { | |
| // Correctly handles non-monomorphic calls, so there is no need for ensure_monomorphic_enough. | |
| ty::Adt(adt, _) => { | |
| ConstValue::from_target_usize(adt.variants().len() as u64, &tcx) | |
| } | |
| ty::Alias(..) | ty::Param(_) | ty::Placeholder(_) | ty::Infer(_) => { | |
| throw_inval!(TooGeneric) | |
| } | |
| ty::Pat(..) => unreachable!(), | |
| ty::Bound(_, _) => bug!("bound ty during ctfe"), | |
| ty::Bool | |
| | ty::Char | |
| | ty::Int(_) | |
| | ty::Uint(_) | |
| | ty::Float(_) | |
| | ty::Foreign(_) | |
| | ty::Str | |
| | ty::Array(_, _) | |
| | ty::Slice(_) | |
| | ty::RawPtr(_, _) | |
| | ty::Ref(_, _, _) | |
| | ty::FnDef(_, _) | |
| | ty::FnPtr(..) | |
| | ty::Dynamic(_, _) | |
| | ty::Closure(_, _) | |
| | ty::CoroutineClosure(_, _) | |
| | ty::Coroutine(_, _) | |
| | ty::CoroutineWitness(..) | |
| | ty::UnsafeBinder(_) | |
| | ty::Never | |
| | ty::Tuple(_) | |
| | ty::Error(_) => ConstValue::from_target_usize(0u64, &tcx), | |
| }; | |
| let val = self.const_val_to_op(val, dest.layout.ty, Some(dest.layout))?; | |
| self.copy_op(&val, dest)?; | |
| } | |
| sym::caller_location => { | |
| let span = self.find_closest_untracked_caller_location(); | |
| let val = self.tcx.span_as_caller_location(span); | |
| let val = | |
| self.const_val_to_op(val, self.tcx.caller_location_ty(), Some(dest.layout))?; | |
| self.copy_op(&val, dest)?; | |
| } | |
| sym::align_of_val | sym::size_of_val => { | |
| // Avoid `deref_pointer` -- this is not a deref, the ptr does not have to be | |
| // dereferenceable! | |
| let place = self.imm_ptr_to_mplace(&self.read_immediate(&args[0])?)?; | |
| let (size, align) = self | |
| .size_and_align_of_val(&place)? | |
| .ok_or_else(|| err_unsup_format!("`extern type` does not have known layout"))?; | |
| let result = match intrinsic_name { | |
| sym::align_of_val => align.bytes(), | |
| sym::size_of_val => size.bytes(), | |
| _ => bug!(), | |
| }; | |
| self.write_scalar(Scalar::from_target_usize(result, self), dest)?; | |
| } | |
| sym::fadd_algebraic | |
| | sym::fsub_algebraic | |
| | sym::fmul_algebraic | |
| | sym::fdiv_algebraic | |
| | sym::frem_algebraic => { | |
| let a = self.read_immediate(&args[0])?; | |
| let b = self.read_immediate(&args[1])?; | |
| let op = match intrinsic_name { | |
| sym::fadd_algebraic => BinOp::Add, | |
| sym::fsub_algebraic => BinOp::Sub, | |
| sym::fmul_algebraic => BinOp::Mul, | |
| sym::fdiv_algebraic => BinOp::Div, | |
| sym::frem_algebraic => BinOp::Rem, | |
| _ => bug!(), | |
| }; | |
| let res = self.binary_op(op, &a, &b)?; | |
| // `binary_op` already called `generate_nan` if needed. | |
| let res = M::apply_float_nondet(self, res)?; | |
| self.write_immediate(*res, dest)?; | |
| } | |
| sym::ctpop | |
| | sym::cttz | |
| | sym::cttz_nonzero | |
| | sym::ctlz | |
| | sym::ctlz_nonzero | |
| | sym::bswap | |
| | sym::bitreverse => { | |
| let ty = instance_args.type_at(0); | |
| let layout = self.layout_of(ty)?; | |
| let val = self.read_scalar(&args[0])?; | |
| let out_val = self.numeric_intrinsic(intrinsic_name, val, layout, dest.layout)?; | |
| self.write_scalar(out_val, dest)?; | |
| } | |
| sym::saturating_add | sym::saturating_sub => { | |
| let l = self.read_immediate(&args[0])?; | |
| let r = self.read_immediate(&args[1])?; | |
| let val = self.saturating_arith( | |
| if intrinsic_name == sym::saturating_add { BinOp::Add } else { BinOp::Sub }, | |
| &l, | |
| &r, | |
| )?; | |
| self.write_scalar(val, dest)?; | |
| } | |
| sym::discriminant_value => { | |
| let place = self.deref_pointer(&args[0])?; | |
| let variant = self.read_discriminant(&place)?; | |
| let discr = self.discriminant_for_variant(place.layout.ty, variant)?; | |
| self.write_immediate(*discr, dest)?; | |
| } | |
| sym::exact_div => { | |
| let l = self.read_immediate(&args[0])?; | |
| let r = self.read_immediate(&args[1])?; | |
| self.exact_div(&l, &r, dest)?; | |
| } | |
| sym::copy => { | |
| self.copy_intrinsic(&args[0], &args[1], &args[2], /*nonoverlapping*/ false)?; | |
| } | |
| sym::write_bytes => { | |
| self.write_bytes_intrinsic(&args[0], &args[1], &args[2], "write_bytes")?; | |
| } | |
| sym::compare_bytes => { | |
| let result = self.compare_bytes_intrinsic(&args[0], &args[1], &args[2])?; | |
| self.write_scalar(result, dest)?; | |
| } | |
| sym::arith_offset => { | |
| let ptr = self.read_pointer(&args[0])?; | |
| let offset_count = self.read_target_isize(&args[1])?; | |
| let pointee_ty = instance_args.type_at(0); | |
| let pointee_size = i64::try_from(self.layout_of(pointee_ty)?.size.bytes()).unwrap(); | |
| let offset_bytes = offset_count.wrapping_mul(pointee_size); | |
| let offset_ptr = ptr.wrapping_signed_offset(offset_bytes, self); | |
| self.write_pointer(offset_ptr, dest)?; | |
| } | |
| sym::ptr_offset_from | sym::ptr_offset_from_unsigned => { | |
| let a = self.read_pointer(&args[0])?; | |
| let b = self.read_pointer(&args[1])?; | |
| let usize_layout = self.layout_of(self.tcx.types.usize)?; | |
| let isize_layout = self.layout_of(self.tcx.types.isize)?; | |
| // Get offsets for both that are at least relative to the same base. | |
| // With `OFFSET_IS_ADDR` this is trivial; without it we need either | |
| // two integers or two pointers into the same allocation. | |
| let (a_offset, b_offset, is_addr) = if M::Provenance::OFFSET_IS_ADDR { | |
| (a.addr().bytes(), b.addr().bytes(), /*is_addr*/ true) | |
| } else { | |
| match (self.ptr_try_get_alloc_id(a, 0), self.ptr_try_get_alloc_id(b, 0)) { | |
| (Err(a), Err(b)) => { | |
| // Neither pointer points to an allocation, so they are both absolute. | |
| (a, b, /*is_addr*/ true) | |
| } | |
| (Ok((a_alloc_id, a_offset, _)), Ok((b_alloc_id, b_offset, _))) | |
| if a_alloc_id == b_alloc_id => | |
| { | |
| // Found allocation for both, and it's the same. | |
| // Use these offsets for distance calculation. | |
| (a_offset.bytes(), b_offset.bytes(), /*is_addr*/ false) | |
| } | |
| _ => { | |
| // Not into the same allocation -- this is UB. | |
| throw_ub_format!( | |
| "`{name}` called on two different pointers that are not both derived from the same allocation", | |
| name = intrinsic_name, | |
| ); | |
| } | |
| } | |
| }; | |
| // Compute distance: a - b. | |
| let dist = { | |
| // Addresses are unsigned, so this is a `usize` computation. We have to do the | |
| // overflow check separately anyway. | |
| let (val, overflowed) = { | |
| let a_offset = ImmTy::from_uint(a_offset, usize_layout); | |
| let b_offset = ImmTy::from_uint(b_offset, usize_layout); | |
| self.binary_op(BinOp::SubWithOverflow, &a_offset, &b_offset)? | |
| .to_scalar_pair() | |
| }; | |
| if overflowed.to_bool()? { | |
| // a < b | |
| if intrinsic_name == sym::ptr_offset_from_unsigned { | |
| throw_ub_format!( | |
| "`ptr_offset_from_unsigned` called when first pointer has smaller {is_addr} than second: {a_offset} < {b_offset}", | |
| a_offset = a_offset, | |
| b_offset = b_offset, | |
| is_addr = if is_addr { "address" } else { "offset" }, | |
| ); | |
| } | |
| // The signed form of the intrinsic allows this. If we interpret the | |
| // difference as isize, we'll get the proper signed difference. If that | |
| // seems *positive* or equal to isize::MIN, they were more than isize::MAX apart. | |
| let dist = val.to_target_isize(self)?; | |
| if dist >= 0 || i128::from(dist) == self.pointer_size().signed_int_min() { | |
| throw_ub_format!( | |
| "`{intrinsic_name}` called when first pointer is too far before second" | |
| ); | |
| } | |
| dist | |
| } else { | |
| // b >= a | |
| let dist = val.to_target_isize(self)?; | |
| // If converting to isize produced a *negative* result, we had an overflow | |
| // because they were more than isize::MAX apart. | |
| if dist < 0 { | |
| throw_ub_format!( | |
| "`{intrinsic_name}` called when first pointer is too far ahead of second" | |
| ); | |
| } | |
| dist | |
| } | |
| }; | |
| // Check that the memory between them is dereferenceable at all, starting from the | |
| // origin pointer: `dist` is `a - b`, so it is based on `b`. | |
| self.check_ptr_access_signed(b, dist, CheckInAllocMsg::Dereferenceable("pointer")) | |
| .map_err_kind(|_| { | |
| // This could mean they point to different allocations, or they point to the same allocation | |
| // but not the entire range between the pointers is in-bounds. | |
| if let Ok((a_alloc_id, ..)) = self.ptr_try_get_alloc_id(a, 0) | |
| && let Ok((b_alloc_id, ..)) = self.ptr_try_get_alloc_id(b, 0) | |
| && a_alloc_id == b_alloc_id | |
| { | |
| err_ub_format!( | |
| "`{intrinsic_name}` called on two different pointers where the memory range between them is not in-bounds of an allocation" | |
| ) | |
| } else { | |
| err_ub_format!( | |
| "`{intrinsic_name}` called on two different pointers that are not both derived from the same allocation" | |
| ) | |
| } | |
| })?; | |
| // Then check that this is also dereferenceable from `a`. This ensures that they are | |
| // derived from the same allocation. | |
| self.check_ptr_access_signed( | |
| a, | |
| dist.checked_neg().unwrap(), // i64::MIN is impossible as no allocation can be that large | |
| CheckInAllocMsg::Dereferenceable("pointer"), | |
| ) | |
| .map_err_kind(|_| { | |
| // Make the error more specific. | |
| err_ub_format!( | |
| "`{intrinsic_name}` called on two different pointers that are not both derived from the same allocation" | |
| ) | |
| })?; | |
| // Perform division by size to compute return value. | |
| let ret_layout = if intrinsic_name == sym::ptr_offset_from_unsigned { | |
| assert!(0 <= dist && dist <= self.target_isize_max()); | |
| usize_layout | |
| } else { | |
| assert!(self.target_isize_min() <= dist && dist <= self.target_isize_max()); | |
| isize_layout | |
| }; | |
| let pointee_layout = self.layout_of(instance_args.type_at(0))?; | |
| // If ret_layout is unsigned, we checked that so is the distance, so we are good. | |
| let val = ImmTy::from_int(dist, ret_layout); | |
| let size = ImmTy::from_int(pointee_layout.size.bytes(), ret_layout); | |
| self.exact_div(&val, &size, dest)?; | |
| } | |
| sym::black_box => { | |
| // These just return their argument | |
| self.copy_op(&args[0], dest)?; | |
| } | |
| sym::raw_eq => { | |
| let result = self.raw_eq_intrinsic(&args[0], &args[1])?; | |
| self.write_scalar(result, dest)?; | |
| } | |
| sym::typed_swap_nonoverlapping => { | |
| self.typed_swap_nonoverlapping_intrinsic(&args[0], &args[1])?; | |
| } | |
| sym::volatile_load => { | |
| let [ptr] = args else { | |
| span_bug!(self.cur_span(), "invalid `volatile_load` call") | |
| }; | |
| let place = self.deref_pointer(ptr)?; | |
| self.copy_op(&place, dest)?; | |
| } | |
| sym::volatile_store => { | |
| let [ptr, val] = args else { | |
| span_bug!(self.cur_span(), "invalid `volatile_store` call") | |
| }; | |
| let place = self.deref_pointer(ptr)?; | |
| self.copy_op(val, &place)?; | |
| } | |
| sym::volatile_set_memory => { | |
| let [ptr, val_byte, count] = args else { | |
| span_bug!(self.cur_span(), "invalid `volatile_set_memory` call") | |
| }; | |
| self.write_bytes_intrinsic(ptr, val_byte, count, "volatile_set_memory")?; | |
| } | |
| sym::vtable_size => { | |
| let ptr = self.read_pointer(&args[0])?; | |
| // `None` because we don't know which trait to expect here; any vtable is okay. | |
| let (size, _align) = self.get_vtable_size_and_align(ptr, None)?; | |
| self.write_scalar(Scalar::from_target_usize(size.bytes(), self), dest)?; | |
| } | |
| sym::vtable_align => { | |
| let ptr = self.read_pointer(&args[0])?; | |
| // `None` because we don't know which trait to expect here; any vtable is okay. | |
| let (_size, align) = self.get_vtable_size_and_align(ptr, None)?; | |
| self.write_scalar(Scalar::from_target_usize(align.bytes(), self), dest)?; | |
| } | |
| sym::minimum_number_nsz_f16 => { | |
| self.float_minmax_intrinsic::<Half>(args, MinMax::MinimumNumberNsz, dest)? | |
| } | |
| sym::minimum_number_nsz_f32 => { | |
| self.float_minmax_intrinsic::<Single>(args, MinMax::MinimumNumberNsz, dest)? | |
| } | |
| sym::minimum_number_nsz_f64 => { | |
| self.float_minmax_intrinsic::<Double>(args, MinMax::MinimumNumberNsz, dest)? | |
| } | |
| sym::minimum_number_nsz_f128 => { | |
| self.float_minmax_intrinsic::<Quad>(args, MinMax::MinimumNumberNsz, dest)? | |
| } | |
| sym::minimumf16 => self.float_minmax_intrinsic::<Half>(args, MinMax::Minimum, dest)?, | |
| sym::minimumf32 => { | |
| self.float_minmax_intrinsic::<Single>(args, MinMax::Minimum, dest)? | |
| } | |
| sym::minimumf64 => { | |
| self.float_minmax_intrinsic::<Double>(args, MinMax::Minimum, dest)? | |
| } | |
| sym::minimumf128 => self.float_minmax_intrinsic::<Quad>(args, MinMax::Minimum, dest)?, | |
| sym::maximum_number_nsz_f16 => { | |
| self.float_minmax_intrinsic::<Half>(args, MinMax::MaximumNumberNsz, dest)? | |
| } | |
| sym::maximum_number_nsz_f32 => { | |
| self.float_minmax_intrinsic::<Single>(args, MinMax::MaximumNumberNsz, dest)? | |
| } | |
| sym::maximum_number_nsz_f64 => { | |
| self.float_minmax_intrinsic::<Double>(args, MinMax::MaximumNumberNsz, dest)? | |
| } | |
| sym::maximum_number_nsz_f128 => { | |
| self.float_minmax_intrinsic::<Quad>(args, MinMax::MaximumNumberNsz, dest)? | |
| } | |
| sym::maximumf16 => self.float_minmax_intrinsic::<Half>(args, MinMax::Maximum, dest)?, | |
| sym::maximumf32 => { | |
| self.float_minmax_intrinsic::<Single>(args, MinMax::Maximum, dest)? | |
| } | |
| sym::maximumf64 => { | |
| self.float_minmax_intrinsic::<Double>(args, MinMax::Maximum, dest)? | |
| } | |
| sym::maximumf128 => self.float_minmax_intrinsic::<Quad>(args, MinMax::Maximum, dest)?, | |
| sym::copysignf16 => self.float_copysign_intrinsic::<Half>(args, dest)?, | |
| sym::copysignf32 => self.float_copysign_intrinsic::<Single>(args, dest)?, | |
| sym::copysignf64 => self.float_copysign_intrinsic::<Double>(args, dest)?, | |
| sym::copysignf128 => self.float_copysign_intrinsic::<Quad>(args, dest)?, | |
| sym::fabs => { | |
| let arg = self.read_immediate(&args[0])?; | |
| let ty::Float(float_ty) = arg.layout.ty.kind() else { | |
| span_bug!( | |
| self.cur_span(), | |
| "non-float type for float intrinsic: {}", | |
| arg.layout.ty, | |
| ); | |
| }; | |
| let out_val = match float_ty { | |
| FloatTy::F16 => self.unop_float_intrinsic::<Half>(intrinsic_name, arg)?, | |
| FloatTy::F32 => self.unop_float_intrinsic::<Single>(intrinsic_name, arg)?, | |
| FloatTy::F64 => self.unop_float_intrinsic::<Double>(intrinsic_name, arg)?, | |
| FloatTy::F128 => self.unop_float_intrinsic::<Quad>(intrinsic_name, arg)?, | |
| }; | |
| self.write_scalar(out_val, dest)?; | |
| } | |
| sym::floorf16 => self.float_round_intrinsic::<Half>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardNegative, | |
| )?, | |
| sym::floorf32 => self.float_round_intrinsic::<Single>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardNegative, | |
| )?, | |
| sym::floorf64 => self.float_round_intrinsic::<Double>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardNegative, | |
| )?, | |
| sym::floorf128 => self.float_round_intrinsic::<Quad>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardNegative, | |
| )?, | |
| sym::ceilf16 => self.float_round_intrinsic::<Half>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardPositive, | |
| )?, | |
| sym::ceilf32 => self.float_round_intrinsic::<Single>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardPositive, | |
| )?, | |
| sym::ceilf64 => self.float_round_intrinsic::<Double>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardPositive, | |
| )?, | |
| sym::ceilf128 => self.float_round_intrinsic::<Quad>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::TowardPositive, | |
| )?, | |
| sym::truncf16 => { | |
| self.float_round_intrinsic::<Half>(args, dest, rustc_apfloat::Round::TowardZero)? | |
| } | |
| sym::truncf32 => { | |
| self.float_round_intrinsic::<Single>(args, dest, rustc_apfloat::Round::TowardZero)? | |
| } | |
| sym::truncf64 => { | |
| self.float_round_intrinsic::<Double>(args, dest, rustc_apfloat::Round::TowardZero)? | |
| } | |
| sym::truncf128 => { | |
| self.float_round_intrinsic::<Quad>(args, dest, rustc_apfloat::Round::TowardZero)? | |
| } | |
| sym::roundf16 => self.float_round_intrinsic::<Half>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToAway, | |
| )?, | |
| sym::roundf32 => self.float_round_intrinsic::<Single>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToAway, | |
| )?, | |
| sym::roundf64 => self.float_round_intrinsic::<Double>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToAway, | |
| )?, | |
| sym::roundf128 => self.float_round_intrinsic::<Quad>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToAway, | |
| )?, | |
| sym::round_ties_even_f16 => self.float_round_intrinsic::<Half>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToEven, | |
| )?, | |
| sym::round_ties_even_f32 => self.float_round_intrinsic::<Single>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToEven, | |
| )?, | |
| sym::round_ties_even_f64 => self.float_round_intrinsic::<Double>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToEven, | |
| )?, | |
| sym::round_ties_even_f128 => self.float_round_intrinsic::<Quad>( | |
| args, | |
| dest, | |
| rustc_apfloat::Round::NearestTiesToEven, | |
| )?, | |
| sym::fmaf16 => self.float_muladd_intrinsic::<Half>(args, dest, MulAddType::Fused)?, | |
| sym::fmaf32 => self.float_muladd_intrinsic::<Single>(args, dest, MulAddType::Fused)?, | |
| sym::fmaf64 => self.float_muladd_intrinsic::<Double>(args, dest, MulAddType::Fused)?, | |
| sym::fmaf128 => self.float_muladd_intrinsic::<Quad>(args, dest, MulAddType::Fused)?, | |
| sym::fmuladdf16 => { | |
| self.float_muladd_intrinsic::<Half>(args, dest, MulAddType::Nondeterministic)? | |
| } | |
| sym::fmuladdf32 => { | |
| self.float_muladd_intrinsic::<Single>(args, dest, MulAddType::Nondeterministic)? | |
| } | |
| sym::fmuladdf64 => { | |
| self.float_muladd_intrinsic::<Double>(args, dest, MulAddType::Nondeterministic)? | |
| } | |
| sym::fmuladdf128 => { | |
| self.float_muladd_intrinsic::<Quad>(args, dest, MulAddType::Nondeterministic)? | |
| } | |
| sym::va_copy => { | |
| let va_list = self.deref_pointer(&args[0])?; | |
| let key_mplace = self.va_list_key_field(&va_list)?; | |
| let key = self.read_pointer(&key_mplace)?; | |
| let varargs = self.get_ptr_va_list(key)?; | |
| let copy_key = self.va_list_ptr(varargs.clone()); | |
| // Zero the destination VaList, so it is fully initialized. | |
| let dest = self.force_allocation(dest)?; | |
| let zeros = std::iter::repeat_n(0u8, dest.layout.size.bytes_usize()); | |
| self.write_bytes_ptr(dest.ptr(), zeros)?; | |
| let copy_key_mplace = self.va_list_key_field(&dest)?; | |
| self.write_pointer(copy_key, ©_key_mplace)?; | |
| } | |
| sym::va_end => { | |
| let va_list = self.deref_pointer(&args[0])?; | |
| let key_mplace = self.va_list_key_field(&va_list)?; | |
| let key = self.read_pointer(&key_mplace)?; | |
| self.deallocate_va_list(key)?; | |
| } | |
| sym::va_arg => { | |
| let va_list = self.deref_pointer(&args[0])?; | |
| let key_mplace = self.va_list_key_field(&va_list)?; | |
| let key = self.read_pointer(&key_mplace)?; | |
| // Invalidate the old list and get its content. We'll recreate the | |
| // new list (one element shorter) below. | |
| let mut varargs = self.deallocate_va_list(key)?; | |
| let Some(arg_mplace) = varargs.pop_front() else { | |
| throw_ub!(VaArgOutOfBounds); | |
| }; | |
| // Error when the caller's argument is not c-variadic compatible with the type | |
| // requested by the callee. | |
| self.validate_c_variadic_argument(&arg_mplace, dest.layout)?; | |
| // Copy the argument, allowing a transmute and relying on the compatibility check | |
| // rejecting conversions between types of different size. | |
| self.copy_op_allow_transmute(&arg_mplace, dest)?; | |
| // Update the VaList pointer. | |
| let new_key = self.va_list_ptr(varargs); | |
| self.write_pointer(new_key, &key_mplace)?; | |
| } | |
| // Unsupported intrinsic: skip the return_to_block below. | |
| _ => return interp_ok(false), | |
| } | |
| trace!("{:?}", self.dump_place(&dest)); | |
| self.return_to_block(ret)?; | |
| interp_ok(true) | |
| } | |
| /// Validate whether the value and type passed by the caller are compatible with the type | |
| /// requested by the callee. Based on section 7.16.1.1 of the C23 specification. | |
| /// | |
| /// The callee requesting a value of a type is valid when that type is compatible with the type | |
| /// provided by the caller (see `validate_c_variadic_compatible_ty`) and, if both types are | |
| /// integers of the same size but different signedness, the passed value must be representable | |
| /// in both types. | |
| fn validate_c_variadic_argument( | |
| &mut self, | |
| arg_mplace: &MPlaceTy<'tcx, M::Provenance>, | |
| callee_type: TyAndLayout<'tcx>, | |
| ) -> InterpResult<'tcx> { | |
| let callee_ty = callee_type.ty; | |
| let caller_ty = arg_mplace.layout.ty; | |
| // Identical types are clearly compatible. | |
| if caller_ty == callee_ty { | |
| return interp_ok(()); | |
| } | |
| // Types of different sizes can never be compatible. | |
| if arg_mplace.layout.size != callee_type.size { | |
| throw_ub_format!( | |
| "va_arg type mismatch: requested `{}` is incompatible with next argument of type `{}`", | |
| callee_ty, | |
| caller_ty, | |
| ) | |
| } | |
| match self.validate_c_variadic_compatible_ty(arg_mplace.layout.ty, callee_type.ty)? { | |
| VarArgCompatible::Compatible => interp_ok(()), | |
| VarArgCompatible::Incompatible => throw_ub_format!( | |
| "va_arg type mismatch: requested `{}` is incompatible with next argument of type `{}`", | |
| callee_ty, | |
| caller_ty, | |
| ), | |
| VarArgCompatible::CastIntTo { source_is_signed } => { | |
| // Check that the value can be represented in the target type. | |
| let size = arg_mplace.layout.size; | |
| let scalar = self.read_scalar(arg_mplace)?; | |
| if scalar.to_int(size)? < 0 { | |
| throw_ub_format!( | |
| "va_arg value mismatch: value `{value}_{caller_ty}` cannot be represented by type `{callee_ty}`", | |
| value = if source_is_signed { | |
| scalar.to_int(size)?.to_string() | |
| } else { | |
| scalar.to_uint(size)?.to_string() | |
| } | |
| ) | |
| } | |
| interp_ok(()) | |
| } | |
| } | |
| } | |
| /// Check whether the caller and callee type are compatible for c-variadic calls. Further | |
| /// validation of the argument value may be needed to detect all UB. | |
| /// | |
| /// Types `T` and `U` are compatible when: | |
| /// | |
| /// - `T` and `U` are the same type. | |
| /// - `T` and `U` are integer types of the same size. | |
| /// - `T` and `U` are both pointers, and their target types are compatible. | |
| /// - `T` is a pointer to [`std::ffi::c_void`] and `U` is a pointer to [`i8`] or [`u8`], | |
| /// or vice versa. | |
| fn validate_c_variadic_compatible_ty( | |
| &mut self, | |
| caller_type: Ty<'tcx>, | |
| callee_type: Ty<'tcx>, | |
| ) -> InterpResult<'tcx, VarArgCompatible> { | |
| if caller_type == callee_type { | |
| return interp_ok(VarArgCompatible::Compatible); | |
| } | |
| if self.layout_of(caller_type)?.size != self.layout_of(callee_type)?.size { | |
| return interp_ok(VarArgCompatible::Incompatible); | |
| } | |
| // Any character type (`char`, `unsigned char` and `signed char`) is compatible with | |
| // `void*`, so the signedness of `c_char` is irrelevant here. | |
| let is_c_char = |ty: Ty<'_>| matches!(ty.kind(), ty::Uint(UintTy::U8) | ty::Int(IntTy::I8)); | |
| match (caller_type.kind(), callee_type.kind()) { | |
| (ty::RawPtr(caller_target_ty, _), ty::RawPtr(callee_target_ty, _)) => { | |
| // In C, types can be qualified by a combination of `const`, `volatile` and | |
| // `restrict`. These properties are irrelevant for the ABI, and don't have an | |
| // equivalent in rust. | |
| // Accept the cast if one type is pointer to void, and the other is a pointer to | |
| // a character type (`char`, `unsigned char` and `signed char`). | |
| if caller_target_ty.is_c_void(self.tcx.tcx) && is_c_char(*callee_target_ty) { | |
| return interp_ok(VarArgCompatible::Compatible); | |
| } | |
| if callee_target_ty.is_c_void(self.tcx.tcx) && is_c_char(*caller_target_ty) { | |
| return interp_ok(VarArgCompatible::Compatible); | |
| } | |
| // Accept the cast if both types are pointers to compatible types. | |
| match self | |
| .validate_c_variadic_compatible_ty(*caller_target_ty, *callee_target_ty)? | |
| { | |
| VarArgCompatible::Incompatible => interp_ok(VarArgCompatible::Incompatible), | |
| VarArgCompatible::Compatible => interp_ok(VarArgCompatible::Compatible), | |
| VarArgCompatible::CastIntTo { source_is_signed: _ } => { | |
| // The integer cast check is not needed when the value is behind a pointer. | |
| interp_ok(VarArgCompatible::Compatible) | |
| } | |
| } | |
| } | |
| (ty::Int(_), ty::Uint(_)) => { | |
| interp_ok(VarArgCompatible::CastIntTo { source_is_signed: true }) | |
| } | |
| (ty::Uint(_), ty::Int(_)) => { | |
| interp_ok(VarArgCompatible::CastIntTo { source_is_signed: false }) | |
| } | |
| (ty::Int(_), ty::Int(_)) | (ty::Uint(_), ty::Uint(_)) => { | |
| // E.g. cast between `usize` and `u64` on a 64-bit platform. | |
| interp_ok(VarArgCompatible::Compatible) | |
| } | |
| _ => interp_ok(VarArgCompatible::Incompatible), | |
| } | |
| } | |
| pub(super) fn eval_nondiverging_intrinsic( | |
| &mut self, | |
| intrinsic: &NonDivergingIntrinsic<'tcx>, | |
| ) -> InterpResult<'tcx> { | |
| match intrinsic { | |
| NonDivergingIntrinsic::Assume(op) => { | |
| let op = self.eval_operand(op, None)?; | |
| let cond = self.read_scalar(&op)?.to_bool()?; | |
| if !cond { | |
| throw_ub_format!("`assume` called with `false`"); | |
| } | |
| interp_ok(()) | |
| } | |
| NonDivergingIntrinsic::CopyNonOverlapping(mir::CopyNonOverlapping { | |
| count, | |
| src, | |
| dst, | |
| }) => { | |
| let src = self.eval_operand(src, None)?; | |
| let dst = self.eval_operand(dst, None)?; | |
| let count = self.eval_operand(count, None)?; | |
| self.copy_intrinsic(&src, &dst, &count, /* nonoverlapping */ true) | |
| } | |
| } | |
| } | |
| pub fn numeric_intrinsic( | |
| &self, | |
| name: Symbol, | |
| val: Scalar<M::Provenance>, | |
| layout: TyAndLayout<'tcx>, | |
| ret_layout: TyAndLayout<'tcx>, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> { | |
| assert!(layout.ty.is_integral(), "invalid type for numeric intrinsic: {}", layout.ty); | |
| let bits = val.to_bits(layout.size)?; // these operations all ignore the sign | |
| let extra = 128 - u128::from(layout.size.bits()); | |
| let bits_out = match name { | |
| sym::ctpop => u128::from(bits.count_ones()), | |
| sym::ctlz_nonzero | sym::cttz_nonzero if bits == 0 => { | |
| throw_ub_format!("`{name}` called on 0"); | |
| } | |
| sym::ctlz | sym::ctlz_nonzero => u128::from(bits.leading_zeros()) - extra, | |
| sym::cttz | sym::cttz_nonzero => u128::from((bits << extra).trailing_zeros()) - extra, | |
| sym::bswap => { | |
| assert_eq!(layout, ret_layout); | |
| (bits << extra).swap_bytes() | |
| } | |
| sym::bitreverse => { | |
| assert_eq!(layout, ret_layout); | |
| (bits << extra).reverse_bits() | |
| } | |
| _ => bug!("not a numeric intrinsic: {}", name), | |
| }; | |
| interp_ok(Scalar::from_uint(bits_out, ret_layout.size)) | |
| } | |
| pub fn exact_div( | |
| &mut self, | |
| a: &ImmTy<'tcx, M::Provenance>, | |
| b: &ImmTy<'tcx, M::Provenance>, | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx> { | |
| assert_eq!(a.layout.ty, b.layout.ty); | |
| assert_matches!(a.layout.ty.kind(), ty::Int(..) | ty::Uint(..)); | |
| // Performs an exact division, resulting in undefined behavior where | |
| // `x % y != 0` or `y == 0` or `x == T::MIN && y == -1`. | |
| // First, check x % y != 0 (or if that computation overflows). | |
| let rem = self.binary_op(BinOp::Rem, a, b)?; | |
| // sign does not matter for 0 test, so `to_bits` is fine | |
| if rem.to_scalar().to_bits(a.layout.size)? != 0 { | |
| throw_ub_format!("exact_div: {a} cannot be divided by {b} without remainder") | |
| } | |
| // `Rem` says this is all right, so we can let `Div` do its job. | |
| let res = self.binary_op(BinOp::Div, a, b)?; | |
| self.write_immediate(*res, dest) | |
| } | |
| pub fn saturating_arith( | |
| &self, | |
| mir_op: BinOp, | |
| l: &ImmTy<'tcx, M::Provenance>, | |
| r: &ImmTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> { | |
| assert_eq!(l.layout.ty, r.layout.ty); | |
| assert_matches!(l.layout.ty.kind(), ty::Int(..) | ty::Uint(..)); | |
| assert_matches!(mir_op, BinOp::Add | BinOp::Sub); | |
| let (val, overflowed) = | |
| self.binary_op(mir_op.wrapping_to_overflowing().unwrap(), l, r)?.to_scalar_pair(); | |
| interp_ok(if overflowed.to_bool()? { | |
| let size = l.layout.size; | |
| if l.layout.backend_repr.is_signed() { | |
| // For signed ints the saturated value depends on the sign of the first | |
| // term since the sign of the second term can be inferred from this and | |
| // the fact that the operation has overflowed (if either is 0 no | |
| // overflow can occur) | |
| let first_term: i128 = l.to_scalar().to_int(l.layout.size)?; | |
| if first_term >= 0 { | |
| // Negative overflow not possible since the positive first term | |
| // can only increase an (in range) negative term for addition | |
| // or corresponding negated positive term for subtraction. | |
| Scalar::from_int(size.signed_int_max(), size) | |
| } else { | |
| // Positive overflow not possible for similar reason. | |
| Scalar::from_int(size.signed_int_min(), size) | |
| } | |
| } else { | |
| // unsigned | |
| if mir_op == BinOp::Add { | |
| // max unsigned | |
| Scalar::from_uint(size.unsigned_int_max(), size) | |
| } else { | |
| // underflow to 0 | |
| Scalar::from_uint(0u128, size) | |
| } | |
| } | |
| } else { | |
| val | |
| }) | |
| } | |
| /// Offsets a pointer by some multiple of its type, returning an error if the pointer leaves its | |
| /// allocation. | |
| pub fn ptr_offset_inbounds( | |
| &self, | |
| ptr: Pointer<Option<M::Provenance>>, | |
| offset_bytes: i64, | |
| ) -> InterpResult<'tcx, Pointer<Option<M::Provenance>>> { | |
| // The offset must be in bounds starting from `ptr`. | |
| self.check_ptr_access_signed( | |
| ptr, | |
| offset_bytes, | |
| CheckInAllocMsg::InboundsPointerArithmetic, | |
| )?; | |
| // This also implies that there is no overflow, so we are done. | |
| interp_ok(ptr.wrapping_signed_offset(offset_bytes, self)) | |
| } | |
| /// Copy `count*size_of::<T>()` many bytes from `*src` to `*dst`. | |
| pub(crate) fn copy_intrinsic( | |
| &mut self, | |
| src: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| dst: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| count: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| nonoverlapping: bool, | |
| ) -> InterpResult<'tcx> { | |
| let count = self.read_target_usize(count)?; | |
| let layout = self.layout_of(src.layout.ty.builtin_deref(true).unwrap())?; | |
| let (size, align) = (layout.size, layout.align.abi); | |
| let size = self.compute_size_in_bytes(size, count).ok_or_else(|| { | |
| err_ub_format!( | |
| "overflow computing total size of `{name}`", | |
| name = if nonoverlapping { "copy_nonoverlapping" } else { "copy" } | |
| ) | |
| })?; | |
| let src = self.read_pointer(src)?; | |
| let dst = self.read_pointer(dst)?; | |
| self.check_ptr_align(src, align)?; | |
| self.check_ptr_align(dst, align)?; | |
| self.mem_copy(src, dst, size, nonoverlapping) | |
| } | |
| /// Does a *typed* swap of `*left` and `*right`. | |
| fn typed_swap_nonoverlapping_intrinsic( | |
| &mut self, | |
| left: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| right: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| ) -> InterpResult<'tcx> { | |
| let left = self.deref_pointer(left)?; | |
| let right = self.deref_pointer(right)?; | |
| assert_eq!(left.layout, right.layout); | |
| assert!(left.layout.is_sized()); | |
| let kind = MemoryKind::Stack; | |
| let temp = self.allocate(left.layout, kind)?; | |
| self.copy_op(&left, &temp)?; // checks alignment of `left` | |
| // We want to always enforce non-overlapping, even if this is a scalar type. | |
| // Therefore we directly use the underlying `mem_copy` here. | |
| self.mem_copy(right.ptr(), left.ptr(), left.layout.size, /*nonoverlapping*/ true)?; | |
| // This means we also need to do the validation of the value that used to be in `right` | |
| // ourselves. This value is now in `left.` The one that started out in `left` already got | |
| // validated by the copy above. | |
| if M::enforce_validity(self, left.layout) { | |
| self.validate_place( | |
| &left.clone().into(), | |
| M::enforce_validity_recursively(self, left.layout), | |
| /*reset_provenance_and_padding*/ true, | |
| )?; | |
| } | |
| self.copy_op(&temp, &right)?; // checks alignment of `right` | |
| self.deallocate_ptr(temp.ptr(), None, kind)?; | |
| interp_ok(()) | |
| } | |
| pub fn write_bytes_intrinsic( | |
| &mut self, | |
| dst: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| byte: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| count: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| name: &'static str, | |
| ) -> InterpResult<'tcx> { | |
| let layout = self.layout_of(dst.layout.ty.builtin_deref(true).unwrap())?; | |
| let dst = self.read_pointer(dst)?; | |
| let byte = self.read_scalar(byte)?.to_u8()?; | |
| let count = self.read_target_usize(count)?; | |
| // `checked_mul` enforces a too small bound (the correct one would probably be target_isize_max), | |
| // but no actual allocation can be big enough for the difference to be noticeable. | |
| let len = self | |
| .compute_size_in_bytes(layout.size, count) | |
| .ok_or_else(|| err_ub_format!("overflow computing total size of `{name}`"))?; | |
| let bytes = std::iter::repeat_n(byte, len.bytes_usize()); | |
| self.write_bytes_ptr(dst, bytes) | |
| } | |
| pub(crate) fn compare_bytes_intrinsic( | |
| &mut self, | |
| left: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| right: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| byte_count: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> { | |
| let left = self.read_pointer(left)?; | |
| let right = self.read_pointer(right)?; | |
| let n = Size::from_bytes(self.read_target_usize(byte_count)?); | |
| let left_bytes = self.read_bytes_ptr_strip_provenance(left, n)?; | |
| let right_bytes = self.read_bytes_ptr_strip_provenance(right, n)?; | |
| // `Ordering`'s discriminants are -1/0/+1, so casting does the right thing. | |
| let result = Ord::cmp(left_bytes, right_bytes) as i32; | |
| interp_ok(Scalar::from_i32(result)) | |
| } | |
| pub(crate) fn raw_eq_intrinsic( | |
| &mut self, | |
| lhs: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| rhs: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> { | |
| let layout = self.layout_of(lhs.layout.ty.builtin_deref(true).unwrap())?; | |
| assert!(layout.is_sized()); | |
| let get_bytes = |this: &InterpCx<'tcx, M>, | |
| op: &OpTy<'tcx, <M as Machine<'tcx>>::Provenance>| | |
| -> InterpResult<'tcx, &[u8]> { | |
| let ptr = this.read_pointer(op)?; | |
| this.check_ptr_align(ptr, layout.align.abi)?; | |
| let Some(alloc_ref) = self.get_ptr_alloc(ptr, layout.size)? else { | |
| // zero-sized access | |
| return interp_ok(&[]); | |
| }; | |
| alloc_ref.get_bytes_strip_provenance() | |
| }; | |
| let lhs_bytes = get_bytes(self, lhs)?; | |
| let rhs_bytes = get_bytes(self, rhs)?; | |
| interp_ok(Scalar::from_bool(lhs_bytes == rhs_bytes)) | |
| } | |
| fn unop_float_intrinsic<F>( | |
| &self, | |
| name: Symbol, | |
| arg: ImmTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let x: F = arg.to_scalar().to_float()?; | |
| match name { | |
| // bitwise, no NaN adjustments | |
| sym::fabs => interp_ok(x.abs().into()), | |
| _ => bug!("not a unary float intrinsic: {}", name), | |
| } | |
| } | |
| fn float_minmax<F>( | |
| &self, | |
| a: Scalar<M::Provenance>, | |
| b: Scalar<M::Provenance>, | |
| op: MinMax, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let a: F = a.to_float()?; | |
| let b: F = b.to_float()?; | |
| let res = if matches!(op, MinMax::MinimumNumberNsz | MinMax::MaximumNumberNsz) && a == b { | |
| // They are definitely not NaN (those are never equal), but they could be `+0` and `-0`. | |
| // Let the machine decide which one to return. | |
| M::equal_float_min_max(self, a, b) | |
| } else { | |
| let result = match op { | |
| MinMax::Minimum => a.minimum(b), | |
| MinMax::MinimumNumberNsz => a.min(b), | |
| MinMax::Maximum => a.maximum(b), | |
| MinMax::MaximumNumberNsz => a.max(b), | |
| }; | |
| self.adjust_nan(result, &[a, b]) | |
| }; | |
| interp_ok(res.into()) | |
| } | |
| fn float_minmax_intrinsic<F>( | |
| &mut self, | |
| args: &[OpTy<'tcx, M::Provenance>], | |
| op: MinMax, | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, ()> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let res = | |
| self.float_minmax::<F>(self.read_scalar(&args[0])?, self.read_scalar(&args[1])?, op)?; | |
| self.write_scalar(res, dest)?; | |
| interp_ok(()) | |
| } | |
| fn float_copysign_intrinsic<F>( | |
| &mut self, | |
| args: &[OpTy<'tcx, M::Provenance>], | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| ) -> InterpResult<'tcx, ()> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let a: F = self.read_scalar(&args[0])?.to_float()?; | |
| let b: F = self.read_scalar(&args[1])?.to_float()?; | |
| // bitwise, no NaN adjustments | |
| self.write_scalar(a.copy_sign(b), dest)?; | |
| interp_ok(()) | |
| } | |
| fn float_round<F>( | |
| &mut self, | |
| x: Scalar<M::Provenance>, | |
| mode: rustc_apfloat::Round, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let x: F = x.to_float()?; | |
| let res = x.round_to_integral(mode).value; | |
| let res = self.adjust_nan(res, &[x]); | |
| interp_ok(res.into()) | |
| } | |
| fn float_round_intrinsic<F>( | |
| &mut self, | |
| args: &[OpTy<'tcx, M::Provenance>], | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| mode: rustc_apfloat::Round, | |
| ) -> InterpResult<'tcx, ()> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let res = self.float_round::<F>(self.read_scalar(&args[0])?, mode)?; | |
| self.write_scalar(res, dest)?; | |
| interp_ok(()) | |
| } | |
| fn float_muladd<F>( | |
| &self, | |
| a: Scalar<M::Provenance>, | |
| b: Scalar<M::Provenance>, | |
| c: Scalar<M::Provenance>, | |
| typ: MulAddType, | |
| ) -> InterpResult<'tcx, Scalar<M::Provenance>> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let a: F = a.to_float()?; | |
| let b: F = b.to_float()?; | |
| let c: F = c.to_float()?; | |
| let fuse = typ == MulAddType::Fused || M::float_fuse_mul_add(self); | |
| let res = if fuse { a.mul_add(b, c).value } else { ((a * b).value + c).value }; | |
| let res = self.adjust_nan(res, &[a, b, c]); | |
| interp_ok(res.into()) | |
| } | |
| fn float_muladd_intrinsic<F>( | |
| &mut self, | |
| args: &[OpTy<'tcx, M::Provenance>], | |
| dest: &PlaceTy<'tcx, M::Provenance>, | |
| typ: MulAddType, | |
| ) -> InterpResult<'tcx, ()> | |
| where | |
| F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>, | |
| { | |
| let a = self.read_scalar(&args[0])?; | |
| let b = self.read_scalar(&args[1])?; | |
| let c = self.read_scalar(&args[2])?; | |
| let res = self.float_muladd::<F>(a, b, c, typ)?; | |
| self.write_scalar(res, dest)?; | |
| interp_ok(()) | |
| } | |
| /// Converts `src` from floating point to integer type `dest_ty` | |
| /// after rounding with mode `round`. | |
| /// Returns `None` if `f` is NaN or out of range. | |
| pub fn float_to_int_checked( | |
| &self, | |
| src: &ImmTy<'tcx, M::Provenance>, | |
| cast_to: TyAndLayout<'tcx>, | |
| round: rustc_apfloat::Round, | |
| ) -> InterpResult<'tcx, Option<ImmTy<'tcx, M::Provenance>>> { | |
| fn float_to_int_inner<'tcx, F: rustc_apfloat::Float, M: Machine<'tcx>>( | |
| ecx: &InterpCx<'tcx, M>, | |
| src: F, | |
| cast_to: TyAndLayout<'tcx>, | |
| round: rustc_apfloat::Round, | |
| ) -> (Scalar<M::Provenance>, rustc_apfloat::Status) { | |
| let int_size = cast_to.layout.size; | |
| match cast_to.ty.kind() { | |
| // Unsigned | |
| ty::Uint(_) => { | |
| let res = src.to_u128_r(int_size.bits_usize(), round, &mut false); | |
| (Scalar::from_uint(res.value, int_size), res.status) | |
| } | |
| // Signed | |
| ty::Int(_) => { | |
| let res = src.to_i128_r(int_size.bits_usize(), round, &mut false); | |
| (Scalar::from_int(res.value, int_size), res.status) | |
| } | |
| // Nothing else | |
| _ => span_bug!( | |
| ecx.cur_span(), | |
| "attempted float-to-int conversion with non-int output type {}", | |
| cast_to.ty, | |
| ), | |
| } | |
| } | |
| let ty::Float(fty) = src.layout.ty.kind() else { | |
| bug!("float_to_int_checked: non-float input type {}", src.layout.ty) | |
| }; | |
| let (val, status) = match fty { | |
| FloatTy::F16 => float_to_int_inner(self, src.to_scalar().to_f16()?, cast_to, round), | |
| FloatTy::F32 => float_to_int_inner(self, src.to_scalar().to_f32()?, cast_to, round), | |
| FloatTy::F64 => float_to_int_inner(self, src.to_scalar().to_f64()?, cast_to, round), | |
| FloatTy::F128 => float_to_int_inner(self, src.to_scalar().to_f128()?, cast_to, round), | |
| }; | |
| if status.intersects( | |
| rustc_apfloat::Status::INVALID_OP | |
| | rustc_apfloat::Status::OVERFLOW | |
| | rustc_apfloat::Status::UNDERFLOW, | |
| ) { | |
| // Floating point value is NaN (flagged with INVALID_OP) or outside the range | |
| // of values of the integer type (flagged with OVERFLOW or UNDERFLOW). | |
| interp_ok(None) | |
| } else { | |
| // Floating point value can be represented by the integer type after rounding. | |
| // The INEXACT flag is ignored on purpose to allow rounding. | |
| interp_ok(Some(ImmTy::from_scalar(val, cast_to))) | |
| } | |
| } | |
| /// Get the MPlace of the key from the place storing the VaList. | |
| pub(super) fn va_list_key_field<P: Projectable<'tcx, M::Provenance>>( | |
| &self, | |
| va_list: &P, | |
| ) -> InterpResult<'tcx, P> { | |
| // The struct wrapped by VaList. | |
| let va_list_inner = self.project_field(va_list, FieldIdx::ZERO)?; | |
| // Find the first pointer field in this struct. The exact index is target-specific. | |
| let ty::Adt(adt, substs) = va_list_inner.layout().ty.kind() else { | |
| bug!("invalid VaListImpl layout"); | |
| }; | |
| for (i, field) in adt.non_enum_variant().fields.iter().enumerate() { | |
| if field.ty(*self.tcx, substs).skip_norm_wip().is_raw_ptr() { | |
| return self.project_field(&va_list_inner, FieldIdx::from_usize(i)); | |
| } | |
| } | |
| bug!("no VaListImpl field is a pointer"); | |
| } | |
| } |