add to_u64() helper method and use it where appropriate

src/tools/miri/src/alloc_addresses/mod.rs

@@ -168,7 +168,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 AllocKind::Dead => unreachable!(),
             };
             // We don't have to expose this pointer yet, we do that in `prepare_for_native_call`.
-            return interp_ok(base_ptr.addr().try_into().unwrap());
+            return interp_ok(base_ptr.addr().to_u64());
         }
         // We are not in native lib mode, so we control the addresses ourselves.
         if let Some((reuse_addr, clock)) = global_state.reuse.take_addr(

src/tools/miri/src/alloc_addresses/reuse_pool.rs

@@ -4,6 +4,7 @@ use rand::Rng;
 use rustc_abi::{Align, Size};
 
 use crate::concurrency::VClock;
+use crate::helpers::ToUsize as _;
 use crate::{MemoryKind, MiriConfig, ThreadId};
 
 const MAX_POOL_SIZE: usize = 64;
@@ -46,7 +47,7 @@ impl ReusePool {
     }
 
     fn subpool(&mut self, align: Align) -> &mut Vec<(u64, Size, ThreadId, VClock)> {
-        let pool_idx: usize = align.bytes().trailing_zeros().try_into().unwrap();
+        let pool_idx: usize = align.bytes().trailing_zeros().to_usize();
         if self.pool.len() <= pool_idx {
             self.pool.resize(pool_idx + 1, Vec::new());
         }

src/tools/miri/src/alloc_bytes.rs

@@ -5,6 +5,8 @@ use std::{alloc, slice};
 use rustc_abi::{Align, Size};
 use rustc_middle::mir::interpret::AllocBytes;
 
+use crate::helpers::ToU64 as _;
+
 /// Allocation bytes that explicitly handle the layout of the data they're storing.
 /// This is necessary to interface with native code that accesses the program store in Miri.
 #[derive(Debug)]
@@ -21,7 +23,7 @@ pub struct MiriAllocBytes {
 impl Clone for MiriAllocBytes {
     fn clone(&self) -> Self {
         let bytes: Cow<'_, [u8]> = Cow::Borrowed(self);
-        let align = Align::from_bytes(self.layout.align().try_into().unwrap()).unwrap();
+        let align = Align::from_bytes(self.layout.align().to_u64()).unwrap();
         MiriAllocBytes::from_bytes(bytes, align)
     }
 }
@@ -90,7 +92,7 @@ impl AllocBytes for MiriAllocBytes {
         let align = align.bytes();
         // SAFETY: `alloc_fn` will only be used with `size != 0`.
         let alloc_fn = |layout| unsafe { alloc::alloc(layout) };
-        let alloc_bytes = MiriAllocBytes::alloc_with(size.try_into().unwrap(), align, alloc_fn)
+        let alloc_bytes = MiriAllocBytes::alloc_with(size.to_u64(), align, alloc_fn)
             .unwrap_or_else(|()| {
                 panic!("Miri ran out of memory: cannot create allocation of {size} bytes")
             });

src/tools/miri/src/helpers.rs

@@ -1423,3 +1423,15 @@ impl ToUsize for u32 {
         self.try_into().unwrap()
     }
 }
+
+/// Similarly, a maximum address size of `u64` is assumed widely here, so let's have ergonomic
+/// converion from `usize` to `u64`.
+pub trait ToU64 {
+    fn to_u64(self) -> u64;
+}
+
+impl ToU64 for usize {
+    fn to_u64(self) -> u64 {
+        self.try_into().unwrap()
+    }
+}

src/tools/miri/src/lib.rs

@@ -133,7 +133,7 @@ pub use crate::eval::{
     AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, MiriEntryFnType, RejectOpWith,
     ValidationMode, create_ecx, eval_entry,
 };
-pub use crate::helpers::{AccessKind, EvalContextExt as _, ToUsize as _};
+pub use crate::helpers::{AccessKind, EvalContextExt as _, ToU64 as _, ToUsize as _};
 pub use crate::intrinsics::EvalContextExt as _;
 pub use crate::machine::{
     AllocExtra, DynMachineCallback, FrameExtra, MachineCallback, MemoryKind, MiriInterpCx,

src/tools/miri/src/shims/backtrace.rs

@@ -25,7 +25,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         let frame_count = this.active_thread_stack().len();
 
-        this.write_scalar(Scalar::from_target_usize(frame_count.try_into().unwrap(), this), dest)
+        this.write_scalar(Scalar::from_target_usize(frame_count.to_u64(), this), dest)
     }
 
     fn handle_miri_get_backtrace(
@@ -70,7 +70,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             }
             1 =>
                 for (i, ptr) in ptrs.into_iter().enumerate() {
-                    let offset = ptr_layout.size.checked_mul(i.try_into().unwrap(), this).unwrap();
+                    let offset = ptr_layout.size.checked_mul(i.to_u64(), this).unwrap();
 
                     let op_place = buf_place.offset(offset, ptr_layout, this)?;
 
@@ -158,11 +158,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             }
             1 => {
                 this.write_scalar(
-                    Scalar::from_target_usize(name.len().try_into().unwrap(), this),
+                    Scalar::from_target_usize(name.len().to_u64(), this),
                     &this.project_field(dest, 0)?,
                 )?;
                 this.write_scalar(
-                    Scalar::from_target_usize(filename.len().try_into().unwrap(), this),
+                    Scalar::from_target_usize(filename.len().to_u64(), this),
                     &this.project_field(dest, 1)?,
                 )?;
             }

src/tools/miri/src/shims/unix/android/thread.rs

@@ -7,7 +7,7 @@ use crate::helpers::check_min_vararg_count;
 use crate::shims::unix::thread::{EvalContextExt as _, ThreadNameResult};
 use crate::*;
 
-const TASK_COMM_LEN: u32 = 16;
+const TASK_COMM_LEN: u64 = 16;
 
 pub fn prctl<'tcx>(
     ecx: &mut MiriInterpCx<'tcx>,
@@ -29,12 +29,8 @@ pub fn prctl<'tcx>(
             let thread = ecx.pthread_self()?;
             // The Linux kernel silently truncates long names.
             // https://www.man7.org/linux/man-pages/man2/PR_SET_NAME.2const.html
-            let res = ecx.pthread_setname_np(
-                thread,
-                name,
-                TASK_COMM_LEN.to_usize(),
-                /* truncate */ true,
-            )?;
+            let res =
+                ecx.pthread_setname_np(thread, name, TASK_COMM_LEN, /* truncate */ true)?;
             assert_eq!(res, ThreadNameResult::Ok);
             Scalar::from_u32(0)
         }
@@ -42,7 +38,7 @@ pub fn prctl<'tcx>(
             let [name] = check_min_vararg_count("prctl(PR_GET_NAME, ...)", varargs)?;
             let name = ecx.read_scalar(name)?;
             let thread = ecx.pthread_self()?;
-            let len = Scalar::from_target_usize(TASK_COMM_LEN.into(), ecx);
+            let len = Scalar::from_target_usize(TASK_COMM_LEN, ecx);
             ecx.check_ptr_access(
                 name.to_pointer(ecx)?,
                 Size::from_bytes(TASK_COMM_LEN),

src/tools/miri/src/shims/unix/freebsd/foreign_items.rs

@@ -24,7 +24,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             // Threading
             "pthread_setname_np" => {
                 let [thread, name] = this.check_shim(abi, Conv::C, link_name, args)?;
-                let max_len = usize::MAX; // FreeBSD does not seem to have a limit.
+                let max_len = u64::MAX; // FreeBSD does not seem to have a limit.
                 let res = match this.pthread_setname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,

src/tools/miri/src/shims/unix/linux/foreign_items.rs

@@ -14,7 +14,7 @@ use crate::*;
 // The documentation of glibc complains that the kernel never exposes
 // TASK_COMM_LEN through the headers, so it's assumed to always be 16 bytes
 // long including a null terminator.
-const TASK_COMM_LEN: u32 = 16;
+const TASK_COMM_LEN: u64 = 16;
 
 pub fn is_dyn_sym(name: &str) -> bool {
     matches!(name, "statx")
@@ -80,7 +80,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let res = match this.pthread_setname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,
-                    TASK_COMM_LEN.to_usize(),
+                    TASK_COMM_LEN,
                     /* truncate */ false,
                 )? {
                     ThreadNameResult::Ok => Scalar::from_u32(0),
@@ -96,7 +96,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // In case of glibc, the length of the output buffer must
                 // be not shorter than TASK_COMM_LEN.
                 let len = this.read_scalar(len)?;
-                let res = if len.to_target_usize(this)? >= TASK_COMM_LEN.into() {
+                let res = if len.to_target_usize(this)? >= TASK_COMM_LEN {
                     match this.pthread_getname_np(
                         this.read_scalar(thread)?,
                         this.read_scalar(name)?,

src/tools/miri/src/shims/unix/macos/foreign_items.rs

@@ -186,7 +186,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let res = match this.pthread_setname_np(
                     thread,
                     this.read_scalar(name)?,
-                    this.eval_libc("MAXTHREADNAMESIZE").to_target_usize(this)?.try_into().unwrap(),
+                    this.eval_libc("MAXTHREADNAMESIZE").to_target_usize(this)?,
                     /* truncate */ false,
                 )? {
                     ThreadNameResult::Ok => Scalar::from_u32(0),

src/tools/miri/src/shims/unix/thread.rs

@@ -86,7 +86,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         &mut self,
         thread: Scalar,
         name: Scalar,
-        name_max_len: usize,
+        name_max_len: u64,
         truncate: bool,
     ) -> InterpResult<'tcx, ThreadNameResult> {
         let this = self.eval_context_mut();
@@ -99,9 +99,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let mut name = this.read_c_str(name)?.to_owned();
 
         // Comparing with `>=` to account for null terminator.
-        if name.len() >= name_max_len {
+        if name.len().to_u64() >= name_max_len {
             if truncate {
-                name.truncate(name_max_len.saturating_sub(1));
+                name.truncate(name_max_len.saturating_sub(1).try_into().unwrap());
             } else {
                 return interp_ok(ThreadNameResult::NameTooLong);
             }

src/tools/miri/src/shims/x86/sha.rs

@@ -43,7 +43,7 @@ pub(super) trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             // We reverse the order because x86 is little endian but the copied implementation uses
             // big endian.
             for (i, part) in val.into_iter().rev().enumerate() {
-                let projected = &ecx.project_index(dest, i.try_into().unwrap())?;
+                let projected = &ecx.project_index(dest, i.to_u64())?;
                 ecx.write_scalar(Scalar::from_u32(part), projected)?;
             }
             interp_ok(())