Rollup merge of #75226 - pnadon:miri-undef-uninit, r=RalfJung

Miri: Renamed "undef" to "uninit"

Renamed remaining references to "undef" to "uninit" when referring to Miri.

Impacted directories are:

- `src/librustc_codegen_llvm/consts.rs`
- `src/librustc_middle/mir/interpret/`
- `src/librustc_middle/ty/print/pretty.rs`
- `src/librustc_mir/`
- `src/tools/clippy/clippy_lints/src/consts.rs`

Upon building Miri based on the new changes it was verified that no changes needed to be made with the Miri project.

Related issue #71193

Author: JohnTitor

src/librustc_codegen_llvm/consts.rs

@@ -41,15 +41,15 @@ pub fn const_alloc_to_llvm(cx: &CodegenCx<'ll, '_>, alloc: &Allocation) -> &'ll
             // some arbitrary byte value.
             //
             // FIXME: relay undef bytes to codegen as undef const bytes
-            let bytes = alloc.inspect_with_undef_and_ptr_outside_interpreter(next_offset..offset);
+            let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(next_offset..offset);
             llvals.push(cx.const_bytes(bytes));
         }
         let ptr_offset = read_target_uint(
             dl.endian,
             // This `inspect` is okay since it is within the bounds of the allocation, it doesn't
             // affect interpreter execution (we inspect the result after interpreter execution),
             // and we properly interpret the relocation as a relocation pointer offset.
-            alloc.inspect_with_undef_and_ptr_outside_interpreter(offset..(offset + pointer_size)),
+            alloc.inspect_with_uninit_and_ptr_outside_interpreter(offset..(offset + pointer_size)),
         )
         .expect("const_alloc_to_llvm: could not read relocation pointer")
             as u64;
@@ -74,7 +74,7 @@ pub fn const_alloc_to_llvm(cx: &CodegenCx<'ll, '_>, alloc: &Allocation) -> &'ll
         // arbitrary byte value.
         //
         // FIXME: relay undef bytes to codegen as undef const bytes
-        let bytes = alloc.inspect_with_undef_and_ptr_outside_interpreter(range);
+        let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(range);
         llvals.push(cx.const_bytes(bytes));
     }
 
@@ -452,7 +452,7 @@ impl StaticMethods for CodegenCx<'ll, 'tcx> {
                     // BSS.
                     let all_bytes_are_zero = alloc.relocations().is_empty()
                         && alloc
-                            .inspect_with_undef_and_ptr_outside_interpreter(0..alloc.len())
+                            .inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len())
                             .iter()
                             .all(|&byte| byte == 0);
 
@@ -480,7 +480,7 @@ impl StaticMethods for CodegenCx<'ll, 'tcx> {
                     // because we are doing this access to inspect the final interpreter state (not
                     // as part of the interpreter execution).
                     let bytes =
-                        alloc.inspect_with_undef_and_ptr_outside_interpreter(0..alloc.len());
+                        alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len());
                     let alloc = llvm::LLVMMDStringInContext(
                         self.llcx,
                         bytes.as_ptr().cast(),

src/librustc_middle/mir/interpret/allocation.rs

@@ -154,10 +154,10 @@ impl<Tag, Extra> Allocation<Tag, Extra> {
     }
 
     /// Looks at a slice which may describe uninitialized bytes or describe a relocation. This differs
-    /// from `get_bytes_with_undef_and_ptr` in that it does no relocation checks (even on the
+    /// from `get_bytes_with_uninit_and_ptr` in that it does no relocation checks (even on the
     /// edges) at all. It further ignores `AllocationExtra` callbacks.
     /// This must not be used for reads affecting the interpreter execution.
-    pub fn inspect_with_undef_and_ptr_outside_interpreter(&self, range: Range<usize>) -> &[u8] {
+    pub fn inspect_with_uninit_and_ptr_outside_interpreter(&self, range: Range<usize>) -> &[u8] {
         &self.bytes[range]
     }
 
@@ -194,7 +194,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
 
     /// The last argument controls whether we error out when there are uninitialized
     /// or pointer bytes. You should never call this, call `get_bytes` or
-    /// `get_bytes_with_undef_and_ptr` instead,
+    /// `get_bytes_with_uninit_and_ptr` instead,
     ///
     /// This function also guarantees that the resulting pointer will remain stable
     /// even when new allocations are pushed to the `HashMap`. `copy_repeatedly` relies
@@ -244,7 +244,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
     ///
     /// It is the caller's responsibility to check bounds and alignment beforehand.
     #[inline]
-    pub fn get_bytes_with_undef_and_ptr(
+    pub fn get_bytes_with_uninit_and_ptr(
         &self,
         cx: &impl HasDataLayout,
         ptr: Pointer<Tag>,
@@ -302,19 +302,19 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
     }
 
     /// Validates that `ptr.offset` and `ptr.offset + size` do not point to the middle of a
-    /// relocation. If `allow_ptr_and_undef` is `false`, also enforces that the memory in the
+    /// relocation. If `allow_uninit_and_ptr` is `false`, also enforces that the memory in the
     /// given range contains neither relocations nor uninitialized bytes.
     pub fn check_bytes(
         &self,
         cx: &impl HasDataLayout,
         ptr: Pointer<Tag>,
         size: Size,
-        allow_ptr_and_undef: bool,
+        allow_uninit_and_ptr: bool,
     ) -> InterpResult<'tcx> {
         // Check bounds and relocations on the edges.
-        self.get_bytes_with_undef_and_ptr(cx, ptr, size)?;
+        self.get_bytes_with_uninit_and_ptr(cx, ptr, size)?;
         // Check uninit and ptr.
-        if !allow_ptr_and_undef {
+        if !allow_uninit_and_ptr {
             self.check_init(ptr, size)?;
             self.check_relocations(cx, ptr, size)?;
         }
@@ -361,7 +361,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
         size: Size,
     ) -> InterpResult<'tcx, ScalarMaybeUninit<Tag>> {
         // `get_bytes_unchecked` tests relocation edges.
-        let bytes = self.get_bytes_with_undef_and_ptr(cx, ptr, size)?;
+        let bytes = self.get_bytes_with_uninit_and_ptr(cx, ptr, size)?;
         // Uninit check happens *after* we established that the alignment is correct.
         // We must not return `Ok()` for unaligned pointers!
         if self.is_init(ptr, size).is_err() {
@@ -594,7 +594,7 @@ impl InitMaskCompressed {
 /// Transferring the initialization mask to other allocations.
 impl<Tag, Extra> Allocation<Tag, Extra> {
     /// Creates a run-length encoding of the initialization mask.
-    pub fn compress_undef_range(&self, src: Pointer<Tag>, size: Size) -> InitMaskCompressed {
+    pub fn compress_uninit_range(&self, src: Pointer<Tag>, size: Size) -> InitMaskCompressed {
         // Since we are copying `size` bytes from `src` to `dest + i * size` (`for i in 0..repeat`),
         // a naive initialization mask copying algorithm would repeatedly have to read the initialization mask from
         // the source and write it to the destination. Even if we optimized the memory accesses,
@@ -636,8 +636,8 @@ impl<Tag, Extra> Allocation<Tag, Extra> {
         size: Size,
         repeat: u64,
     ) {
-        // An optimization where we can just overwrite an entire range of definedness bits if
-        // they are going to be uniformly `1` or `0`.
+        // An optimization where we can just overwrite an entire range of initialization
+        // bits if they are going to be uniformly `1` or `0`.
         if defined.ranges.len() <= 1 {
             self.init_mask.set_range_inbounds(
                 dest.offset,

src/librustc_middle/mir/interpret/value.rs

@@ -58,7 +58,7 @@ impl<'tcx> ConstValue<'tcx> {
 
     pub fn try_to_str_slice(&self) -> Option<&'tcx str> {
         if let ConstValue::Slice { data, start, end } = *self {
-            ::std::str::from_utf8(data.inspect_with_undef_and_ptr_outside_interpreter(start..end))
+            ::std::str::from_utf8(data.inspect_with_uninit_and_ptr_outside_interpreter(start..end))
                 .ok()
         } else {
             None

src/librustc_middle/ty/print/pretty.rs

@@ -1107,7 +1107,7 @@ pub trait PrettyPrinter<'tcx>:
                 // The `inspect` here is okay since we checked the bounds, and there are
                 // no relocations (we have an active slice reference here). We don't use
                 // this result to affect interpreter execution.
-                let byte_str = data.inspect_with_undef_and_ptr_outside_interpreter(start..end);
+                let byte_str = data.inspect_with_uninit_and_ptr_outside_interpreter(start..end);
                 self.pretty_print_byte_str(byte_str)
             }
             (
@@ -1117,7 +1117,7 @@ pub trait PrettyPrinter<'tcx>:
                 // The `inspect` here is okay since we checked the bounds, and there are no
                 // relocations (we have an active `str` reference here). We don't use this
                 // result to affect interpreter execution.
-                let slice = data.inspect_with_undef_and_ptr_outside_interpreter(start..end);
+                let slice = data.inspect_with_uninit_and_ptr_outside_interpreter(start..end);
                 let s = ::std::str::from_utf8(slice).expect("non utf8 str from miri");
                 p!(write("{:?}", s));
                 Ok(self)

src/librustc_mir/interpret/memory.rs

@@ -926,7 +926,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
         // first copy the relocations to a temporary buffer, because
         // `get_bytes_mut` will clear the relocations, which is correct,
         // since we don't want to keep any relocations at the target.
-        // (`get_bytes_with_undef_and_ptr` below checks that there are no
+        // (`get_bytes_with_uninit_and_ptr` below checks that there are no
         // relocations overlapping the edges; those would not be handled correctly).
         let relocations =
             self.get_raw(src.alloc_id)?.prepare_relocation_copy(self, src, size, dest, length);
@@ -935,7 +935,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
 
         // This checks relocation edges on the src.
         let src_bytes =
-            self.get_raw(src.alloc_id)?.get_bytes_with_undef_and_ptr(&tcx, src, size)?.as_ptr();
+            self.get_raw(src.alloc_id)?.get_bytes_with_uninit_and_ptr(&tcx, src, size)?.as_ptr();
         let dest_bytes =
             self.get_raw_mut(dest.alloc_id)?.get_bytes_mut(&tcx, dest, size * length)?; // `Size` multiplication
 
@@ -948,7 +948,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
         let dest_bytes = dest_bytes.as_mut_ptr();
 
         // Prepare a copy of the initialization mask.
-        let compressed = self.get_raw(src.alloc_id)?.compress_undef_range(src, size);
+        let compressed = self.get_raw(src.alloc_id)?.compress_uninit_range(src, size);
 
         if compressed.no_bytes_init() {
             // Fast path: If all bytes are `uninit` then there is nothing to copy. The target range

src/librustc_mir/interpret/operand.rs

@@ -106,7 +106,7 @@ impl<Tag: Copy> std::fmt::Display for ImmTy<'tcx, Tag> {
                 }
                 ScalarMaybeUninit::Uninit => cx.typed_value(
                     |mut this| {
-                        this.write_str("{undef ")?;
+                        this.write_str("{uninit ")?;
                         Ok(this)
                     },
                     |this| this.print_type(ty),

src/librustc_mir/interpret/place.rs

@@ -61,7 +61,7 @@ impl<Tag> MemPlaceMeta<Tag> {
 pub struct MemPlace<Tag = ()> {
     /// A place may have an integral pointer for ZSTs, and since it might
     /// be turned back into a reference before ever being dereferenced.
-    /// However, it may never be undef.
+    /// However, it may never be uninit.
     pub ptr: Scalar<Tag>,
     pub align: Align,
     /// Metadata for unsized places. Interpretation is up to the type.
@@ -729,7 +729,7 @@ where
                         "Size mismatch when writing bits"
                     )
                 }
-                Immediate::Scalar(ScalarMaybeUninit::Uninit) => {} // undef can have any size
+                Immediate::Scalar(ScalarMaybeUninit::Uninit) => {} // uninit can have any size
                 Immediate::ScalarPair(_, _) => {
                     // FIXME: Can we check anything here?
                 }

src/librustc_mir/interpret/validity.rs

@@ -508,12 +508,12 @@ impl<'rt, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> ValidityVisitor<'rt, 'mir, '
                     }
                 } else {
                     // At run-time, for now, we accept *anything* for these types, including
-                    // undef. We should fix that, but let's start low.
+                    // uninit. We should fix that, but let's start low.
                 }
                 Ok(true)
             }
             ty::RawPtr(..) => {
-                // We are conservative with undef for integers, but try to
+                // We are conservative with uninit for integers, but try to
                 // actually enforce the strict rules for raw pointers (mostly because
                 // that lets us re-use `ref_to_mplace`).
                 let place = try_validation!(
@@ -807,12 +807,12 @@ impl<'rt, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
                 // reject it.  However, that's good: We don't inherently want
                 // to reject those pointers, we just do not have the machinery to
                 // talk about parts of a pointer.
-                // We also accept undef, for consistency with the slow path.
+                // We also accept uninit, for consistency with the slow path.
                 match self.ecx.memory.get_raw(ptr.alloc_id)?.check_bytes(
                     self.ecx,
                     ptr,
                     size,
-                    /*allow_ptr_and_undef*/ self.ref_tracking_for_consts.is_none(),
+                    /*allow_uninit_and_ptr*/ self.ref_tracking_for_consts.is_none(),
                 ) {
                     // In the happy case, we needn't check anything else.
                     Ok(()) => {}

src/librustc_mir/transform/const_prop.rs

@@ -1076,7 +1076,7 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> {
                 // ```rust
                 // let mut x = 42;
                 // x = SOME_MUTABLE_STATIC;
-                // // x must now be undefined
+                // // x must now be uninit
                 // ```
                 // FIXME: we overzealously erase the entire local, because that's easier to
                 // implement.

src/librustc_mir/util/pretty.rs

@@ -743,8 +743,8 @@ fn write_allocation_bytes<Tag: Copy + Debug, Extra>(
         if let Some(&(tag, target_id)) = alloc.relocations().get(&i) {
             // Memory with a relocation must be defined
             let j = i.bytes_usize();
-            let offset =
-                alloc.inspect_with_undef_and_ptr_outside_interpreter(j..j + ptr_size.bytes_usize());
+            let offset = alloc
+                .inspect_with_uninit_and_ptr_outside_interpreter(j..j + ptr_size.bytes_usize());
             let offset = read_target_uint(tcx.data_layout.endian, offset).unwrap();
             let offset = Size::from_bytes(offset);
             let relocation_width = |bytes| bytes * 3;
@@ -803,7 +803,7 @@ fn write_allocation_bytes<Tag: Copy + Debug, Extra>(
 
             // Checked definedness (and thus range) and relocations. This access also doesn't
             // influence interpreter execution but is only for debugging.
-            let c = alloc.inspect_with_undef_and_ptr_outside_interpreter(j..j + 1)[0];
+            let c = alloc.inspect_with_uninit_and_ptr_outside_interpreter(j..j + 1)[0];
             write!(w, "{:02x}", c)?;
             if c.is_ascii_control() || c >= 0x80 {
                 ascii.push('.');

src/tools/clippy/clippy_lints/src/consts.rs

@@ -517,7 +517,7 @@ pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
         ty::ConstKind::Value(ConstValue::Slice { data, start, end }) => match result.ty.kind {
             ty::Ref(_, tam, _) => match tam.kind {
                 ty::Str => String::from_utf8(
-                    data.inspect_with_undef_and_ptr_outside_interpreter(start..end)
+                    data.inspect_with_uninit_and_ptr_outside_interpreter(start..end)
                         .to_owned(),
                 )
                 .ok()
@@ -530,7 +530,7 @@ pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
             ty::Array(sub_type, len) => match sub_type.kind {
                 ty::Float(FloatTy::F32) => match miri_to_const(len) {
                     Some(Constant::Int(len)) => alloc
-                        .inspect_with_undef_and_ptr_outside_interpreter(0..(4 * len as usize))
+                        .inspect_with_uninit_and_ptr_outside_interpreter(0..(4 * len as usize))
                         .to_owned()
                         .chunks(4)
                         .map(|chunk| {
@@ -544,7 +544,7 @@ pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
                 },
                 ty::Float(FloatTy::F64) => match miri_to_const(len) {
                     Some(Constant::Int(len)) => alloc
-                        .inspect_with_undef_and_ptr_outside_interpreter(0..(8 * len as usize))
+                        .inspect_with_uninit_and_ptr_outside_interpreter(0..(8 * len as usize))
                         .to_owned()
                         .chunks(8)
                         .map(|chunk| {