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Rollup merge of #124030 - RalfJung:adjust_alloc_base_pointer, r=oli-obk

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interpret: pass MemoryKind to adjust_alloc_base_pointer

Another puzzle piece for https://github.com/rust-lang/miri/pull/3475.

The 2nd commit renames base_pointer -> root_pointer; that's how Tree Borrows already calls them and I think the term is more clear than "base pointer". In particular, this distinguishes it from "base address", since a root pointer can point anywhere into an allocation, not just its base address.

https://github.com/rust-lang/rust/pull/124018 has been rolled up already so I couldn't add it there any more.

r? ```@oli-obk```
This commit is contained in:
Matthias Krüger 2024-04-17 18:01:38 +02:00 • committed by GitHub
commit 6388167811
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14 changed files with 85 additions and 65 deletions
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35
compiler/rustc_const_eval/src/interpret/machine.rs
View file

@ -288,28 +288,19 @@ pub trait Machine<'mir, 'tcx: 'mir>: Sized {
}
/// Return the `AllocId` for the given thread-local static in the current thread.
fn thread_local_static_base_pointer(
fn thread_local_static_pointer(
_ecx: &mut InterpCx<'mir, 'tcx, Self>,
def_id: DefId,
) -> InterpResult<'tcx, Pointer<Self::Provenance>> {
throw_unsup!(ThreadLocalStatic(def_id))
}
/// Return the root pointer for the given `extern static`.
fn extern_static_base_pointer(
/// Return the `AllocId` for the given `extern static`.
fn extern_static_pointer(
ecx: &InterpCx<'mir, 'tcx, Self>,
def_id: DefId,
) -> InterpResult<'tcx, Pointer<Self::Provenance>>;
/// Return a "base" pointer for the given allocation: the one that is used for direct
/// accesses to this static/const/fn allocation, or the one returned from the heap allocator.
///
/// Not called on `extern` or thread-local statics (those use the methods above).
fn adjust_alloc_base_pointer(
ecx: &InterpCx<'mir, 'tcx, Self>,
ptr: Pointer,
) -> InterpResult<'tcx, Pointer<Self::Provenance>>;
/// "Int-to-pointer cast"
fn ptr_from_addr_cast(
ecx: &InterpCx<'mir, 'tcx, Self>,
@ -336,6 +327,8 @@ pub trait Machine<'mir, 'tcx: 'mir>: Sized {
/// Called to adjust allocations to the Provenance and AllocExtra of this machine.
///
/// If `alloc` contains pointers, then they are all pointing to globals.
///
/// The way we construct allocations is to always first construct it without extra and then add
/// the extra. This keeps uniform code paths for handling both allocations created by CTFE for
/// globals, and allocations created by Miri during evaluation.
@ -354,6 +347,19 @@ pub trait Machine<'mir, 'tcx: 'mir>: Sized {
kind: Option<MemoryKind<Self::MemoryKind>>,
) -> InterpResult<'tcx, Cow<'b, Allocation<Self::Provenance, Self::AllocExtra, Self::Bytes>>>;
/// Return a "root" pointer for the given allocation: the one that is used for direct
/// accesses to this static/const/fn allocation, or the one returned from the heap allocator.
///
/// Not called on `extern` or thread-local statics (those use the methods above).
///
/// `kind` is the kind of the allocation the pointer points to; it can be `None` when
/// it's a global and `GLOBAL_KIND` is `None`.
fn adjust_alloc_root_pointer(
ecx: &InterpCx<'mir, 'tcx, Self>,
ptr: Pointer,
kind: Option<MemoryKind<Self::MemoryKind>>,
) -> InterpResult<'tcx, Pointer<Self::Provenance>>;
/// Evaluate the inline assembly.
///
/// This should take care of jumping to the next block (one of `targets`) when asm goto
@ -592,7 +598,7 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) {
Ok(alloc)
}
fn extern_static_base_pointer(
fn extern_static_pointer(
ecx: &InterpCx<$mir, $tcx, Self>,
def_id: DefId,
) -> InterpResult<$tcx, Pointer> {
@ -601,9 +607,10 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) {
}
#[inline(always)]
fn adjust_alloc_base_pointer(
fn adjust_alloc_root_pointer(
_ecx: &InterpCx<$mir, $tcx, Self>,
ptr: Pointer<CtfeProvenance>,
_kind: Option<MemoryKind<Self::MemoryKind>>,
) -> InterpResult<$tcx, Pointer<CtfeProvenance>> {
Ok(ptr)
}

18
compiler/rustc_const_eval/src/interpret/memory.rs
View file

@ -165,7 +165,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
///
/// This function can fail only if `ptr` points to an `extern static`.
#[inline]
pub fn global_base_pointer(
pub fn global_root_pointer(
&self,
ptr: Pointer<CtfeProvenance>,
) -> InterpResult<'tcx, Pointer<M::Provenance>> {
@ -178,12 +178,18 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
bug!("global memory cannot point to thread-local static")
}
Some(GlobalAlloc::Static(def_id)) if self.tcx.is_foreign_item(def_id) => {
return M::extern_static_base_pointer(self, def_id);
return M::extern_static_pointer(self, def_id);
}
None => {
assert!(
self.memory.extra_fn_ptr_map.contains_key(&alloc_id),
"{alloc_id:?} is neither global nor a function pointer"
);
}
_ => {}
}
// And we need to get the provenance.
M::adjust_alloc_base_pointer(self, ptr)
M::adjust_alloc_root_pointer(self, ptr, M::GLOBAL_KIND.map(MemoryKind::Machine))
}
pub fn fn_ptr(&mut self, fn_val: FnVal<'tcx, M::ExtraFnVal>) -> Pointer<M::Provenance> {
@ -197,9 +203,9 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
id
}
};
// Functions are global allocations, so make sure we get the right base pointer.
// Functions are global allocations, so make sure we get the right root pointer.
// We know this is not an `extern static` so this cannot fail.
self.global_base_pointer(Pointer::from(id)).unwrap()
self.global_root_pointer(Pointer::from(id)).unwrap()
}
pub fn allocate_ptr(
@ -240,7 +246,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
);
let alloc = M::adjust_allocation(self, id, Cow::Owned(alloc), Some(kind))?;
self.memory.alloc_map.insert(id, (kind, alloc.into_owned()));
M::adjust_alloc_base_pointer(self, Pointer::from(id))
M::adjust_alloc_root_pointer(self, Pointer::from(id), Some(kind))
}
pub fn reallocate_ptr(

6
compiler/rustc_const_eval/src/interpret/operand.rs
View file

@ -764,7 +764,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
// Other cases need layout.
let adjust_scalar = |scalar| -> InterpResult<'tcx, _> {
Ok(match scalar {
Scalar::Ptr(ptr, size) => Scalar::Ptr(self.global_base_pointer(ptr)?, size),
Scalar::Ptr(ptr, size) => Scalar::Ptr(self.global_root_pointer(ptr)?, size),
Scalar::Int(int) => Scalar::Int(int),
})
};
@ -772,7 +772,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
let imm = match val_val {
mir::ConstValue::Indirect { alloc_id, offset } => {
// This is const data, no mutation allowed.
let ptr = self.global_base_pointer(Pointer::new(
let ptr = self.global_root_pointer(Pointer::new(
CtfeProvenance::from(alloc_id).as_immutable(),
offset,
))?;
@ -784,7 +784,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
// This is const data, no mutation allowed.
let alloc_id = self.tcx.reserve_and_set_memory_alloc(data);
let ptr = Pointer::new(CtfeProvenance::from(alloc_id).as_immutable(), Size::ZERO);
Immediate::new_slice(self.global_base_pointer(ptr)?.into(), meta, self)
Immediate::new_slice(self.global_root_pointer(ptr)?.into(), meta, self)
}
};
Ok(OpTy { op: Operand::Immediate(imm), layout })

2
compiler/rustc_const_eval/src/interpret/place.rs
View file

@ -1010,7 +1010,7 @@ where
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
// This must be an allocation in `tcx`
let _ = self.tcx.global_alloc(raw.alloc_id);
let ptr = self.global_base_pointer(Pointer::from(raw.alloc_id))?;
let ptr = self.global_root_pointer(Pointer::from(raw.alloc_id))?;
let layout = self.layout_of(raw.ty)?;
Ok(self.ptr_to_mplace(ptr.into(), layout))
}

2
compiler/rustc_const_eval/src/interpret/step.rs
View file

@ -144,7 +144,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
use rustc_middle::mir::Rvalue::*;
match *rvalue {
ThreadLocalRef(did) => {
let ptr = M::thread_local_static_base_pointer(self, did)?;
let ptr = M::thread_local_static_pointer(self, did)?;
self.write_pointer(ptr, &dest)?;
}

2
compiler/rustc_const_eval/src/interpret/traits.rs
View file

@ -28,7 +28,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
ensure_monomorphic_enough(*self.tcx, poly_trait_ref)?;
let vtable_symbolic_allocation = self.tcx.reserve_and_set_vtable_alloc(ty, poly_trait_ref);
let vtable_ptr = self.global_base_pointer(Pointer::from(vtable_symbolic_allocation))?;
let vtable_ptr = self.global_root_pointer(Pointer::from(vtable_symbolic_allocation))?;
Ok(vtable_ptr.into())
}