Auto merge of #108096 - matthiaskrgr:rollup-ncexzf6, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - #107034 (Migrating rustc_infer to session diagnostics (part 4))
 - #107972 (Fix unintentional UB in ui tests)
 - #108010 (Make `InferCtxt::can_eq` and `InferCtxt::can_sub` return booleans)
 - #108021 (make x look for x.py if shell script does not exist)
 - #108047 (Use `target` instead of `machine` for mir interpreter integer handling.)
 - #108049 (Don't suggest `#[doc(hidden)]` trait methods with matching return type)
 - #108066 (Better names for illegal impl trait positions)
 - #108076 (rustdoc: Use more let chain)
 - #108088 (clarify correctness of `black_box`)
 - #108094 (Demonstrate I/O in File examples)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

src/borrow_tracker/stacked_borrows/mod.rs

@@ -718,7 +718,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'
             throw_ub!(PointerOutOfBounds {
                 alloc_id,
                 alloc_size,
-                ptr_offset: this.machine_usize_to_isize(base_offset.bytes()),
+                ptr_offset: this.target_usize_to_isize(base_offset.bytes()),
                 ptr_size: size,
                 msg: CheckInAllocMsg::InboundsTest
             });

src/eval.rs

@@ -236,7 +236,7 @@ impl MainThreadState {
                     this.machine.main_fn_ret_place.unwrap().ptr,
                     this.machine.layouts.isize,
                 );
-                let exit_code = this.read_machine_isize(&ret_place.into())?;
+                let exit_code = this.read_target_isize(&ret_place.into())?;
                 // Need to call this ourselves since we are not going to return to the scheduler
                 // loop, and we want the main thread TLS to not show up as memory leaks.
                 this.terminate_active_thread()?;
@@ -287,7 +287,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
     // First argument is constructed later, because it's skipped if the entry function uses #[start].
 
     // Second argument (argc): length of `config.args`.
-    let argc = Scalar::from_machine_usize(u64::try_from(config.args.len()).unwrap(), &ecx);
+    let argc = Scalar::from_target_usize(u64::try_from(config.args.len()).unwrap(), &ecx);
     // Third argument (`argv`): created from `config.args`.
     let argv = {
         // Put each argument in memory, collect pointers.

src/helpers.rs

@@ -758,10 +758,10 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let this = self.eval_context_mut();
         let seconds_place = this.mplace_field(tp, 0)?;
         let seconds_scalar = this.read_scalar(&seconds_place.into())?;
-        let seconds = seconds_scalar.to_machine_isize(this)?;
+        let seconds = seconds_scalar.to_target_isize(this)?;
         let nanoseconds_place = this.mplace_field(tp, 1)?;
         let nanoseconds_scalar = this.read_scalar(&nanoseconds_place.into())?;
-        let nanoseconds = nanoseconds_scalar.to_machine_isize(this)?;
+        let nanoseconds = nanoseconds_scalar.to_target_isize(this)?;
 
         Ok(try {
             // tv_sec must be non-negative.

src/intptrcast.rs

@@ -207,7 +207,7 @@ impl<'mir, 'tcx> GlobalStateInner {
                     .checked_add(max(size.bytes(), 1))
                     .ok_or_else(|| err_exhaust!(AddressSpaceFull))?;
                 // Even if `Size` didn't overflow, we might still have filled up the address space.
-                if global_state.next_base_addr > ecx.machine_usize_max() {
+                if global_state.next_base_addr > ecx.target_usize_max() {
                     throw_exhaust!(AddressSpaceFull);
                 }
                 // Given that `next_base_addr` increases in each allocation, pushing the

src/operator.rs

@@ -56,7 +56,7 @@ impl<'mir, 'tcx> EvalContextExt<'tcx> for super::MiriInterpCx<'mir, 'tcx> {
             Offset => {
                 assert!(left.layout.ty.is_unsafe_ptr());
                 let ptr = left.to_scalar().to_pointer(self)?;
-                let offset = right.to_scalar().to_machine_isize(self)?;
+                let offset = right.to_scalar().to_target_isize(self)?;
 
                 let pointee_ty =
                     left.layout.ty.builtin_deref(true).expect("Offset called on non-ptr type").ty;
@@ -73,14 +73,14 @@ impl<'mir, 'tcx> EvalContextExt<'tcx> for super::MiriInterpCx<'mir, 'tcx> {
                 // We do the actual operation with usize-typed scalars.
                 let left = ImmTy::from_uint(ptr.addr().bytes(), self.machine.layouts.usize);
                 let right = ImmTy::from_uint(
-                    right.to_scalar().to_machine_usize(self)?,
+                    right.to_scalar().to_target_usize(self)?,
                     self.machine.layouts.usize,
                 );
                 let (result, overflowing, _ty) =
                     self.overflowing_binary_op(bin_op, &left, &right)?;
                 // Construct a new pointer with the provenance of `ptr` (the LHS).
                 let result_ptr =
-                    Pointer::new(ptr.provenance, Size::from_bytes(result.to_machine_usize(self)?));
+                    Pointer::new(ptr.provenance, Size::from_bytes(result.to_target_usize(self)?));
                 (Scalar::from_maybe_pointer(result_ptr, self), overflowing, left.layout.ty)
             }
 

src/shims/backtrace.rs

@@ -24,7 +24,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
         let frame_count = this.active_thread_stack().len();
 
-        this.write_scalar(Scalar::from_machine_usize(frame_count.try_into().unwrap(), this), dest)
+        this.write_scalar(Scalar::from_target_usize(frame_count.try_into().unwrap(), this), dest)
     }
 
     fn handle_miri_get_backtrace(
@@ -205,11 +205,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             }
             1 => {
                 this.write_scalar(
-                    Scalar::from_machine_usize(name.len().try_into().unwrap(), this),
+                    Scalar::from_target_usize(name.len().try_into().unwrap(), this),
                     &this.mplace_field(&dest, 0)?.into(),
                 )?;
                 this.write_scalar(
-                    Scalar::from_machine_usize(filename.len().try_into().unwrap(), this),
+                    Scalar::from_target_usize(filename.len().try_into().unwrap(), this),
                     &this.mplace_field(&dest, 1)?.into(),
                 )?;
             }

src/shims/env.rs

@@ -323,7 +323,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.assert_target_os_is_unix("getcwd");
 
         let buf = this.read_pointer(buf_op)?;
-        let size = this.read_machine_usize(size_op)?;
+        let size = this.read_target_usize(size_op)?;
 
         if let IsolatedOp::Reject(reject_with) = this.machine.isolated_op {
             this.reject_in_isolation("`getcwd`", reject_with)?;

src/shims/ffi_support.rs

@@ -36,7 +36,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             ty::Int(IntTy::Isize) => {
                 // This will fail if host != target, but then the entire FFI thing probably won't work well
                 // in that situation.
-                return Ok(CArg::ISize(k.to_machine_isize(cx)?.try_into().unwrap()));
+                return Ok(CArg::ISize(k.to_target_isize(cx)?.try_into().unwrap()));
             }
             // the uints
             ty::Uint(UintTy::U8) => {
@@ -54,7 +54,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             ty::Uint(UintTy::Usize) => {
                 // This will fail if host != target, but then the entire FFI thing probably won't work well
                 // in that situation.
-                return Ok(CArg::USize(k.to_machine_usize(cx)?.try_into().unwrap()));
+                return Ok(CArg::USize(k.to_target_usize(cx)?.try_into().unwrap()));
             }
             _ => {}
         }

src/shims/foreign_items.rs

@@ -449,7 +449,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [ptr, out, out_size] = this.check_shim(abi, Abi::Rust, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
                 let out = this.read_pointer(out)?;
-                let out_size = this.read_scalar(out_size)?.to_machine_usize(this)?;
+                let out_size = this.read_scalar(out_size)?.to_target_usize(this)?;
 
                 // The host affects program behavior here, so this requires isolation to be disabled.
                 this.check_no_isolation("`miri_host_to_target_path`")?;
@@ -490,7 +490,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [bytes] = this.check_shim(abi, Abi::Rust, link_name, args)?;
                 let (ptr, len) = this.read_immediate(bytes)?.to_scalar_pair();
                 let ptr = ptr.to_pointer(this)?;
-                let len = len.to_machine_usize(this)?;
+                let len = len.to_target_usize(this)?;
                 let msg = this.read_bytes_ptr_strip_provenance(ptr, Size::from_bytes(len))?;
 
                 // Note: we're ignoring errors writing to host stdout/stderr.
@@ -504,15 +504,15 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             // Standard C allocation
             "malloc" => {
                 let [size] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
-                let size = this.read_machine_usize(size)?;
+                let size = this.read_target_usize(size)?;
                 let res = this.malloc(size, /*zero_init:*/ false, MiriMemoryKind::C)?;
                 this.write_pointer(res, dest)?;
             }
             "calloc" => {
                 let [items, len] =
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
-                let items = this.read_machine_usize(items)?;
-                let len = this.read_machine_usize(len)?;
+                let items = this.read_target_usize(items)?;
+                let len = this.read_target_usize(len)?;
                 let size = items
                     .checked_mul(len)
                     .ok_or_else(|| err_ub_format!("overflow during calloc size computation"))?;
@@ -528,16 +528,16 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [old_ptr, new_size] =
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let old_ptr = this.read_pointer(old_ptr)?;
-                let new_size = this.read_machine_usize(new_size)?;
+                let new_size = this.read_target_usize(new_size)?;
                 let res = this.realloc(old_ptr, new_size, MiriMemoryKind::C)?;
                 this.write_pointer(res, dest)?;
             }
 
             // Rust allocation
             "__rust_alloc" | "miri_alloc" => {
                 let [size, align] = this.check_shim(abi, Abi::Rust, link_name, args)?;
-                let size = this.read_machine_usize(size)?;
-                let align = this.read_machine_usize(align)?;
+                let size = this.read_target_usize(size)?;
+                let align = this.read_target_usize(align)?;
 
                 let default = |this: &mut MiriInterpCx<'mir, 'tcx>| {
                     Self::check_alloc_request(size, align)?;
@@ -569,8 +569,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             }
             "__rust_alloc_zeroed" => {
                 let [size, align] = this.check_shim(abi, Abi::Rust, link_name, args)?;
-                let size = this.read_machine_usize(size)?;
-                let align = this.read_machine_usize(align)?;
+                let size = this.read_target_usize(size)?;
+                let align = this.read_target_usize(align)?;
 
                 return this.emulate_allocator(Symbol::intern("__rg_alloc_zeroed"), |this| {
                     Self::check_alloc_request(size, align)?;
@@ -593,8 +593,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "__rust_dealloc" | "miri_dealloc" => {
                 let [ptr, old_size, align] = this.check_shim(abi, Abi::Rust, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
-                let old_size = this.read_machine_usize(old_size)?;
-                let align = this.read_machine_usize(align)?;
+                let old_size = this.read_target_usize(old_size)?;
+                let align = this.read_target_usize(align)?;
 
                 let default = |this: &mut MiriInterpCx<'mir, 'tcx>| {
                     let memory_kind = match link_name.as_str() {
@@ -625,9 +625,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [ptr, old_size, align, new_size] =
                     this.check_shim(abi, Abi::Rust, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
-                let old_size = this.read_machine_usize(old_size)?;
-                let align = this.read_machine_usize(align)?;
-                let new_size = this.read_machine_usize(new_size)?;
+                let old_size = this.read_target_usize(old_size)?;
+                let align = this.read_target_usize(align)?;
+                let new_size = this.read_target_usize(new_size)?;
                 // No need to check old_size; we anyway check that they match the allocation.
 
                 return this.emulate_allocator(Symbol::intern("__rg_realloc"), |this| {
@@ -651,7 +651,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let left = this.read_pointer(left)?;
                 let right = this.read_pointer(right)?;
-                let n = Size::from_bytes(this.read_machine_usize(n)?);
+                let n = Size::from_bytes(this.read_target_usize(n)?);
 
                 let result = {
                     let left_bytes = this.read_bytes_ptr_strip_provenance(left, n)?;
@@ -672,7 +672,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
                 let val = this.read_scalar(val)?.to_i32()?;
-                let num = this.read_machine_usize(num)?;
+                let num = this.read_target_usize(num)?;
                 // The docs say val is "interpreted as unsigned char".
                 #[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
                 let val = val as u8;
@@ -696,7 +696,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
                 let val = this.read_scalar(val)?.to_i32()?;
-                let num = this.read_machine_usize(num)?;
+                let num = this.read_target_usize(num)?;
                 // The docs say val is "interpreted as unsigned char".
                 #[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
                 let val = val as u8;
@@ -717,7 +717,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let ptr = this.read_pointer(ptr)?;
                 let n = this.read_c_str(ptr)?.len();
                 this.write_scalar(
-                    Scalar::from_machine_usize(u64::try_from(n).unwrap(), this),
+                    Scalar::from_target_usize(u64::try_from(n).unwrap(), this),
                     dest,
                 )?;
             }

src/shims/intrinsics/mod.rs

@@ -111,8 +111,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let ty_layout = this.layout_of(ty)?;
                 let val_byte = this.read_scalar(val_byte)?.to_u8()?;
                 let ptr = this.read_pointer(ptr)?;
-                let count = this.read_machine_usize(count)?;
-                // `checked_mul` enforces a too small bound (the correct one would probably be machine_isize_max),
+                let count = this.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 byte_count = ty_layout.size.checked_mul(count, this).ok_or_else(|| {
                     err_ub_format!("overflow computing total size of `{intrinsic_name}`")
@@ -124,7 +124,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [ptr, mask] = check_arg_count(args)?;
 
                 let ptr = this.read_pointer(ptr)?;
-                let mask = this.read_machine_usize(mask)?;
+                let mask = this.read_target_usize(mask)?;
 
                 let masked_addr = Size::from_bytes(ptr.addr().bytes() & mask);