diff --git a/rust-version b/rust-version
index af94ff9ea6b..78b9a110aa7 100644
--- a/rust-version
+++ b/rust-version
@@ -1 +1 @@
-2019147c5642c08cdb9ad4cacd97dd1fa4ffa701
+acb8934fd57b3c2740c4abac0a5728c2c9b1423b
diff --git a/src/concurrency/data_race.rs b/src/concurrency/data_race.rs
index 87f64db26d3..2e54ddaaba1 100644
--- a/src/concurrency/data_race.rs
+++ b/src/concurrency/data_race.rs
@@ -438,8 +438,8 @@ impl MemoryCellClocks {
 }
 
 /// Evaluation context extensions.
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: MiriInterpCxExt<'mir, 'tcx> {
     /// Atomic variant of read_scalar_at_offset.
     fn read_scalar_at_offset_atomic(
         &self,
@@ -940,8 +940,8 @@ impl VClockAlloc {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for MiriEvalContext<'mir, 'tcx> {}
-trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriInterpCxExt<'mir, 'tcx> {
     /// Temporarily allow data-races to occur. This should only be used in
     /// one of these cases:
     /// - One of the appropriate `validate_atomic` functions will be called to
@@ -950,7 +950,7 @@ trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
     /// cannot be accessed by the interpreted program.
     /// - Execution of the interpreted program execution has halted.
     #[inline]
-    fn allow_data_races_ref<R>(&self, op: impl FnOnce(&MiriEvalContext<'mir, 'tcx>) -> R) -> R {
+    fn allow_data_races_ref<R>(&self, op: impl FnOnce(&MiriInterpCx<'mir, 'tcx>) -> R) -> R {
         let this = self.eval_context_ref();
         if let Some(data_race) = &this.machine.data_race {
             let old = data_race.ongoing_action_data_race_free.replace(true);
@@ -969,7 +969,7 @@ trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
     #[inline]
     fn allow_data_races_mut<R>(
         &mut self,
-        op: impl FnOnce(&mut MiriEvalContext<'mir, 'tcx>) -> R,
+        op: impl FnOnce(&mut MiriInterpCx<'mir, 'tcx>) -> R,
     ) -> R {
         let this = self.eval_context_mut();
         if let Some(data_race) = &this.machine.data_race {
diff --git a/src/concurrency/sync.rs b/src/concurrency/sync.rs
index 81e5a83a1fb..d301ced8511 100644
--- a/src/concurrency/sync.rs
+++ b/src/concurrency/sync.rs
@@ -159,8 +159,8 @@ pub(crate) struct SynchronizationState {
 }
 
 // Private extension trait for local helper methods
-impl<'mir, 'tcx: 'mir> EvalContextExtPriv<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExtPriv<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Take a reader out of the queue waiting for the lock.
     /// Returns `true` if some thread got the rwlock.
     #[inline]
@@ -208,8 +208,8 @@ trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
 // cases, the function calls are infallible and it is the client's (shim
 // implementation's) responsibility to detect and deal with erroneous
 // situations.
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     #[inline]
     /// Create state for a new mutex.
     fn mutex_create(&mut self) -> MutexId {
@@ -222,7 +222,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     /// otherwise returns the value from the closure
     fn mutex_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, MutexId>
     where
-        F: FnOnce(&mut MiriEvalContext<'mir, 'tcx>, MutexId) -> InterpResult<'tcx, Option<MutexId>>,
+        F: FnOnce(&mut MiriInterpCx<'mir, 'tcx>, MutexId) -> InterpResult<'tcx, Option<MutexId>>,
     {
         let this = self.eval_context_mut();
         let next_index = this.machine.threads.sync.mutexes.next_index();
@@ -322,10 +322,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     /// otherwise returns the value from the closure
     fn rwlock_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, RwLockId>
     where
-        F: FnOnce(
-            &mut MiriEvalContext<'mir, 'tcx>,
-            RwLockId,
-        ) -> InterpResult<'tcx, Option<RwLockId>>,
+        F: FnOnce(&mut MiriInterpCx<'mir, 'tcx>, RwLockId) -> InterpResult<'tcx, Option<RwLockId>>,
     {
         let this = self.eval_context_mut();
         let next_index = this.machine.threads.sync.rwlocks.next_index();
@@ -492,7 +489,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     fn condvar_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, CondvarId>
     where
         F: FnOnce(
-            &mut MiriEvalContext<'mir, 'tcx>,
+            &mut MiriInterpCx<'mir, 'tcx>,
             CondvarId,
         ) -> InterpResult<'tcx, Option<CondvarId>>,
     {
diff --git a/src/concurrency/thread.rs b/src/concurrency/thread.rs
index 78a357dd6af..f1a3d19fb4c 100644
--- a/src/concurrency/thread.rs
+++ b/src/concurrency/thread.rs
@@ -32,8 +32,9 @@ pub enum SchedulingAction {
 
 /// Timeout callbacks can be created by synchronization primitives to tell the
 /// scheduler that they should be called once some period of time passes.
-type TimeoutCallback<'mir, 'tcx> =
-    Box<dyn FnOnce(&mut InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>) -> InterpResult<'tcx> + 'tcx>;
+type TimeoutCallback<'mir, 'tcx> = Box<
+    dyn FnOnce(&mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>) -> InterpResult<'tcx> + 'tcx,
+>;
 
 /// A thread identifier.
 #[derive(Clone, Copy, Debug, PartialOrd, Ord, PartialEq, Eq, Hash)]
@@ -253,7 +254,7 @@ impl<'mir, 'tcx> Default for ThreadManager<'mir, 'tcx> {
 }
 
 impl<'mir, 'tcx: 'mir> ThreadManager<'mir, 'tcx> {
-    pub(crate) fn init(ecx: &mut MiriEvalContext<'mir, 'tcx>) {
+    pub(crate) fn init(ecx: &mut MiriInterpCx<'mir, 'tcx>) {
         if ecx.tcx.sess.target.os.as_ref() != "windows" {
             // The main thread can *not* be joined on except on windows.
             ecx.machine.threads.threads[ThreadId::new(0)].join_status = ThreadJoinStatus::Detached;
@@ -628,8 +629,8 @@ impl<'mir, 'tcx: 'mir> ThreadManager<'mir, 'tcx> {
 }
 
 // Public interface to thread management.
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Get a thread-specific allocation id for the given thread-local static.
     /// If needed, allocate a new one.
     fn get_or_create_thread_local_alloc(
diff --git a/src/concurrency/weak_memory.rs b/src/concurrency/weak_memory.rs
index 0e579a38af8..bac403e9ec7 100644
--- a/src/concurrency/weak_memory.rs
+++ b/src/concurrency/weak_memory.rs
@@ -456,9 +456,9 @@ impl StoreElement {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
-    crate::MiriEvalContextExt<'mir, 'tcx>
+    crate::MiriInterpCxExt<'mir, 'tcx>
 {
     // If weak memory emulation is enabled, check if this atomic op imperfectly overlaps with a previous
     // atomic read or write. If it does, then we require it to be ordered (non-racy) with all previous atomic
@@ -502,7 +502,7 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
         let (alloc_id, base_offset, ..) = this.ptr_get_alloc_id(place.ptr)?;
         if let (
             crate::AllocExtra { weak_memory: Some(alloc_buffers), .. },
-            crate::Evaluator { data_race: Some(global), threads, .. },
+            crate::MiriMachine { data_race: Some(global), threads, .. },
         ) = this.get_alloc_extra_mut(alloc_id)?
         {
             if atomic == AtomicRwOrd::SeqCst {
@@ -544,7 +544,7 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
                     validate,
                 )?;
                 if global.track_outdated_loads && recency == LoadRecency::Outdated {
-                    register_diagnostic(NonHaltingDiagnostic::WeakMemoryOutdatedLoad);
+                    this.emit_diagnostic(NonHaltingDiagnostic::WeakMemoryOutdatedLoad);
                 }
 
                 return Ok(loaded);
@@ -567,7 +567,7 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
         let (alloc_id, base_offset, ..) = this.ptr_get_alloc_id(dest.ptr)?;
         if let (
             crate::AllocExtra { weak_memory: Some(alloc_buffers), .. },
-            crate::Evaluator { data_race: Some(global), threads, .. },
+            crate::MiriMachine { data_race: Some(global), threads, .. },
         ) = this.get_alloc_extra_mut(alloc_id)?
         {
             if atomic == AtomicWriteOrd::SeqCst {
diff --git a/src/diagnostics.rs b/src/diagnostics.rs
index 8ba2995662b..868c85c04a8 100644
--- a/src/diagnostics.rs
+++ b/src/diagnostics.rs
@@ -1,11 +1,9 @@
-use std::cell::RefCell;
 use std::fmt;
 use std::num::NonZeroU64;
 
 use log::trace;
 
-use rustc_middle::ty;
-use rustc_span::{source_map::DUMMY_SP, Span, SpanData, Symbol};
+use rustc_span::{source_map::DUMMY_SP, SpanData, Symbol};
 use rustc_target::abi::{Align, Size};
 
 use crate::stacked_borrows::{diagnostics::TagHistory, AccessKind};
@@ -89,15 +87,15 @@ enum DiagLevel {
 /// Attempts to prune a stacktrace to omit the Rust runtime, and returns a bool indicating if any
 /// frames were pruned. If the stacktrace does not have any local frames, we conclude that it must
 /// be pointing to a problem in the Rust runtime itself, and do not prune it at all.
-fn prune_stacktrace<'mir, 'tcx>(
-    ecx: &InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+fn prune_stacktrace<'tcx>(
     mut stacktrace: Vec<FrameInfo<'tcx>>,
+    machine: &MiriMachine<'_, 'tcx>,
 ) -> (Vec<FrameInfo<'tcx>>, bool) {
-    match ecx.machine.backtrace_style {
+    match machine.backtrace_style {
         BacktraceStyle::Off => {
             // Remove all frames marked with `caller_location` -- that attribute indicates we
             // usually want to point at the caller, not them.
-            stacktrace.retain(|frame| !frame.instance.def.requires_caller_location(*ecx.tcx));
+            stacktrace.retain(|frame| !frame.instance.def.requires_caller_location(machine.tcx));
             // Retain one frame so that we can print a span for the error itself
             stacktrace.truncate(1);
             (stacktrace, false)
@@ -107,11 +105,12 @@ fn prune_stacktrace<'mir, 'tcx>(
             // Only prune frames if there is at least one local frame. This check ensures that if
             // we get a backtrace that never makes it to the user code because it has detected a
             // bug in the Rust runtime, we don't prune away every frame.
-            let has_local_frame = stacktrace.iter().any(|frame| ecx.machine.is_local(frame));
+            let has_local_frame = stacktrace.iter().any(|frame| machine.is_local(frame));
             if has_local_frame {
                 // Remove all frames marked with `caller_location` -- that attribute indicates we
                 // usually want to point at the caller, not them.
-                stacktrace.retain(|frame| !frame.instance.def.requires_caller_location(*ecx.tcx));
+                stacktrace
+                    .retain(|frame| !frame.instance.def.requires_caller_location(machine.tcx));
 
                 // This is part of the logic that `std` uses to select the relevant part of a
                 // backtrace. But here, we only look for __rust_begin_short_backtrace, not
@@ -121,7 +120,7 @@ fn prune_stacktrace<'mir, 'tcx>(
                     .into_iter()
                     .take_while(|frame| {
                         let def_id = frame.instance.def_id();
-                        let path = ecx.tcx.tcx.def_path_str(def_id);
+                        let path = machine.tcx.def_path_str(def_id);
                         !path.contains("__rust_begin_short_backtrace")
                     })
                     .collect::<Vec<_>>();
@@ -132,7 +131,7 @@ fn prune_stacktrace<'mir, 'tcx>(
                 // This len check ensures that we don't somehow remove every frame, as doing so breaks
                 // the primary error message.
                 while stacktrace.len() > 1
-                    && stacktrace.last().map_or(false, |frame| !ecx.machine.is_local(frame))
+                    && stacktrace.last().map_or(false, |frame| !machine.is_local(frame))
                 {
                     stacktrace.pop();
                 }
@@ -146,7 +145,7 @@ fn prune_stacktrace<'mir, 'tcx>(
 
 /// Emit a custom diagnostic without going through the miri-engine machinery
 pub fn report_error<'tcx, 'mir>(
-    ecx: &InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+    ecx: &InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>,
     e: InterpErrorInfo<'tcx>,
 ) -> Option<i64> {
     use InterpError::*;
@@ -256,17 +255,17 @@ pub fn report_error<'tcx, 'mir>(
     };
 
     let stacktrace = ecx.generate_stacktrace();
-    let (stacktrace, was_pruned) = prune_stacktrace(ecx, stacktrace);
+    let (stacktrace, was_pruned) = prune_stacktrace(stacktrace, &ecx.machine);
     e.print_backtrace();
     msg.insert(0, e.to_string());
     report_msg(
-        ecx,
         DiagLevel::Error,
         &if let Some(title) = title { format!("{}: {}", title, msg[0]) } else { msg[0].clone() },
         msg,
         vec![],
         helps,
         &stacktrace,
+        &ecx.machine,
     );
 
     // Include a note like `std` does when we omit frames from a backtrace
@@ -306,17 +305,17 @@ pub fn report_error<'tcx, 'mir>(
 /// We want to present a multi-line span message for some errors. Diagnostics do not support this
 /// directly, so we pass the lines as a `Vec<String>` and display each line after the first with an
 /// additional `span_label` or `note` call.
-fn report_msg<'mir, 'tcx>(
-    ecx: &InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+fn report_msg<'tcx>(
     diag_level: DiagLevel,
     title: &str,
     span_msg: Vec<String>,
     notes: Vec<(Option<SpanData>, String)>,
     helps: Vec<(Option<SpanData>, String)>,
     stacktrace: &[FrameInfo<'tcx>],
+    machine: &MiriMachine<'_, 'tcx>,
 ) {
     let span = stacktrace.first().map_or(DUMMY_SP, |fi| fi.span);
-    let sess = ecx.tcx.sess;
+    let sess = machine.tcx.sess;
     let mut err = match diag_level {
         DiagLevel::Error => sess.struct_span_err(span, title).forget_guarantee(),
         DiagLevel::Warning => sess.struct_span_warn(span, title),
@@ -357,7 +356,7 @@ fn report_msg<'mir, 'tcx>(
     }
     // Add backtrace
     for (idx, frame_info) in stacktrace.iter().enumerate() {
-        let is_local = ecx.machine.is_local(frame_info);
+        let is_local = machine.is_local(frame_info);
         // No span for non-local frames and the first frame (which is the error site).
         if is_local && idx > 0 {
             err.span_note(frame_info.span, &frame_info.to_string());
@@ -369,164 +368,115 @@ fn report_msg<'mir, 'tcx>(
     err.emit();
 }
 
-thread_local! {
-    static DIAGNOSTICS: RefCell<Vec<NonHaltingDiagnostic>> = RefCell::new(Vec::new());
-}
+impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
+    pub fn emit_diagnostic(&self, e: NonHaltingDiagnostic) {
+        use NonHaltingDiagnostic::*;
 
-/// Schedule a diagnostic for emitting. This function works even if you have no `InterpCx` available.
-/// The diagnostic will be emitted after the current interpreter step is finished.
-pub fn register_diagnostic(e: NonHaltingDiagnostic) {
-    DIAGNOSTICS.with(|diagnostics| diagnostics.borrow_mut().push(e));
-}
+        let stacktrace =
+            MiriInterpCx::generate_stacktrace_from_stack(self.threads.active_thread_stack());
+        let (stacktrace, _was_pruned) = prune_stacktrace(stacktrace, self);
 
-/// Remember enough about the topmost frame so that we can restore the stack
-/// after a step was taken.
-pub struct TopFrameInfo<'tcx> {
-    stack_size: usize,
-    instance: Option<ty::Instance<'tcx>>,
-    span: Span,
-}
+        let (title, diag_level) = match e {
+            RejectedIsolatedOp(_) => ("operation rejected by isolation", DiagLevel::Warning),
+            Int2Ptr { .. } => ("integer-to-pointer cast", DiagLevel::Warning),
+            CreatedPointerTag(..)
+            | PoppedPointerTag(..)
+            | CreatedCallId(..)
+            | CreatedAlloc(..)
+            | FreedAlloc(..)
+            | ProgressReport { .. }
+            | WeakMemoryOutdatedLoad => ("tracking was triggered", DiagLevel::Note),
+        };
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
-    fn preprocess_diagnostics(&self) -> TopFrameInfo<'tcx> {
-        // Ensure we have no lingering diagnostics.
-        DIAGNOSTICS.with(|diagnostics| assert!(diagnostics.borrow().is_empty()));
-
-        let this = self.eval_context_ref();
-        if this.active_thread_stack().is_empty() {
-            // Diagnostics can happen even with the empty stack (e.g. deallocation of thread-local statics).
-            return TopFrameInfo { stack_size: 0, instance: None, span: DUMMY_SP };
-        }
-        let frame = this.frame();
-
-        TopFrameInfo {
-            stack_size: this.active_thread_stack().len(),
-            instance: Some(frame.instance),
-            span: frame.current_span(),
-        }
-    }
-
-    /// Emit all diagnostics that were registed with `register_diagnostics`
-    fn process_diagnostics(&self, info: TopFrameInfo<'tcx>) {
-        let this = self.eval_context_ref();
-        DIAGNOSTICS.with(|diagnostics| {
-            let mut diagnostics = diagnostics.borrow_mut();
-            if diagnostics.is_empty() {
-                return;
-            }
-            // We need to fix up the stack trace, because the machine has already
-            // stepped to the next statement.
-            let mut stacktrace = this.generate_stacktrace();
-            // Remove newly pushed frames.
-            while stacktrace.len() > info.stack_size {
-                stacktrace.remove(0);
-            }
-            // Add popped frame back.
-            if stacktrace.len() < info.stack_size {
-                assert!(
-                    stacktrace.len() == info.stack_size - 1,
-                    "we should never pop more than one frame at once"
-                );
-                let frame_info = FrameInfo {
-                    instance: info.instance.unwrap(),
-                    span: info.span,
-                    lint_root: None,
-                };
-                stacktrace.insert(0, frame_info);
-            } else if let Some(instance) = info.instance {
-                // Adjust topmost frame.
-                stacktrace[0].span = info.span;
-                assert_eq!(
-                    stacktrace[0].instance, instance,
-                    "we should not pop and push a frame in one step"
-                );
-            }
-
-            let (stacktrace, _was_pruned) = prune_stacktrace(this, stacktrace);
-
-            // Show diagnostics.
-            for e in diagnostics.drain(..) {
-                use NonHaltingDiagnostic::*;
-
-                let (title, diag_level) = match e {
-                    RejectedIsolatedOp(_) =>
-                        ("operation rejected by isolation", DiagLevel::Warning),
-                    Int2Ptr { .. } => ("integer-to-pointer cast", DiagLevel::Warning),
-                    CreatedPointerTag(..)
-                    | PoppedPointerTag(..)
-                    | CreatedCallId(..)
-                    | CreatedAlloc(..)
-                    | FreedAlloc(..)
-                    | ProgressReport { .. }
-                    | WeakMemoryOutdatedLoad =>
-                        ("tracking was triggered", DiagLevel::Note),
-                };
-
-                let msg = match e {
-                    CreatedPointerTag(tag, None) =>
-                        format!("created tag {tag:?}"),
-                    CreatedPointerTag(tag, Some((alloc_id, range))) =>
-                        format!("created tag {tag:?} at {alloc_id:?}{range:?}"),
-                    PoppedPointerTag(item, tag) =>
-                        match tag {
-                            None =>
-                                format!(
-                                    "popped tracked tag for item {item:?} due to deallocation",
-                                ),
-                            Some((tag, access)) => {
-                                format!(
-                                    "popped tracked tag for item {item:?} due to {access:?} access for {tag:?}",
-                                )
-                            }
-                        },
-                    CreatedCallId(id) =>
-                        format!("function call with id {id}"),
-                    CreatedAlloc(AllocId(id), size, align, kind) =>
+        let msg = match e {
+            CreatedPointerTag(tag, None) => format!("created tag {tag:?}"),
+            CreatedPointerTag(tag, Some((alloc_id, range))) =>
+                format!("created tag {tag:?} at {alloc_id:?}{range:?}"),
+            PoppedPointerTag(item, tag) =>
+                match tag {
+                    None => format!("popped tracked tag for item {item:?} due to deallocation",),
+                    Some((tag, access)) => {
                         format!(
-                            "created {kind} allocation of {size} bytes (alignment {align} bytes) with id {id}",
-                            size = size.bytes(),
-                            align = align.bytes(),
-                        ),
-                    FreedAlloc(AllocId(id)) =>
-                        format!("freed allocation with id {id}"),
-                    RejectedIsolatedOp(ref op) =>
-                        format!("{op} was made to return an error due to isolation"),
-                    ProgressReport { .. } =>
-                        format!("progress report: current operation being executed is here"),
-                    Int2Ptr { .. } =>
-                        format!("integer-to-pointer cast"),
-                    WeakMemoryOutdatedLoad =>
-                        format!("weak memory emulation: outdated value returned from load"),
-                };
-
-                let notes = match e {
-                    ProgressReport { block_count } => {
-                        // It is important that each progress report is slightly different, since
-                        // identical diagnostics are being deduplicated.
-                        vec![
-                            (None, format!("so far, {block_count} basic blocks have been executed")),
-                        ]
+                            "popped tracked tag for item {item:?} due to {access:?} access for {tag:?}",
+                        )
                     }
-                    _ => vec![],
-                };
+                },
+            CreatedCallId(id) => format!("function call with id {id}"),
+            CreatedAlloc(AllocId(id), size, align, kind) =>
+                format!(
+                    "created {kind} allocation of {size} bytes (alignment {align} bytes) with id {id}",
+                    size = size.bytes(),
+                    align = align.bytes(),
+                ),
+            FreedAlloc(AllocId(id)) => format!("freed allocation with id {id}"),
+            RejectedIsolatedOp(ref op) =>
+                format!("{op} was made to return an error due to isolation"),
+            ProgressReport { .. } =>
+                format!("progress report: current operation being executed is here"),
+            Int2Ptr { .. } => format!("integer-to-pointer cast"),
+            WeakMemoryOutdatedLoad =>
+                format!("weak memory emulation: outdated value returned from load"),
+        };
 
-                let helps = match e {
-                    Int2Ptr { details: true } =>
-                        vec![
-                            (None, format!("This program is using integer-to-pointer casts or (equivalently) `ptr::from_exposed_addr`,")),
-                            (None, format!("which means that Miri might miss pointer bugs in this program.")),
-                            (None, format!("See https://doc.rust-lang.org/nightly/std/ptr/fn.from_exposed_addr.html for more details on that operation.")),
-                            (None, format!("To ensure that Miri does not miss bugs in your program, use Strict Provenance APIs (https://doc.rust-lang.org/nightly/std/ptr/index.html#strict-provenance, https://crates.io/crates/sptr) instead.")),
-                            (None, format!("You can then pass the `-Zmiri-strict-provenance` flag to Miri, to ensure you are not relying on `from_exposed_addr` semantics.")),
-                            (None, format!("Alternatively, the `-Zmiri-permissive-provenance` flag disables this warning.")),
-                        ],
-                    _ => vec![],
-                };
-
-                report_msg(this, diag_level, title, vec![msg], notes, helps, &stacktrace);
+        let notes = match e {
+            ProgressReport { block_count } => {
+                // It is important that each progress report is slightly different, since
+                // identical diagnostics are being deduplicated.
+                vec![(None, format!("so far, {block_count} basic blocks have been executed"))]
             }
-        });
+            _ => vec![],
+        };
+
+        let helps = match e {
+            Int2Ptr { details: true } =>
+                vec![
+                    (
+                        None,
+                        format!(
+                            "This program is using integer-to-pointer casts or (equivalently) `ptr::from_exposed_addr`,"
+                        ),
+                    ),
+                    (
+                        None,
+                        format!("which means that Miri might miss pointer bugs in this program."),
+                    ),
+                    (
+                        None,
+                        format!(
+                            "See https://doc.rust-lang.org/nightly/std/ptr/fn.from_exposed_addr.html for more details on that operation."
+                        ),
+                    ),
+                    (
+                        None,
+                        format!(
+                            "To ensure that Miri does not miss bugs in your program, use Strict Provenance APIs (https://doc.rust-lang.org/nightly/std/ptr/index.html#strict-provenance, https://crates.io/crates/sptr) instead."
+                        ),
+                    ),
+                    (
+                        None,
+                        format!(
+                            "You can then pass the `-Zmiri-strict-provenance` flag to Miri, to ensure you are not relying on `from_exposed_addr` semantics."
+                        ),
+                    ),
+                    (
+                        None,
+                        format!(
+                            "Alternatively, the `-Zmiri-permissive-provenance` flag disables this warning."
+                        ),
+                    ),
+                ],
+            _ => vec![],
+        };
+
+        report_msg(diag_level, title, vec![msg], notes, helps, &stacktrace, self);
+    }
+}
+
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
+    fn emit_diagnostic(&self, e: NonHaltingDiagnostic) {
+        let this = self.eval_context_ref();
+        this.machine.emit_diagnostic(e);
     }
 
     /// We had a panic in Miri itself, try to print something useful.
@@ -538,13 +488,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         let this = self.eval_context_ref();
         let stacktrace = this.generate_stacktrace();
         report_msg(
-            this,
             DiagLevel::Note,
             "the place in the program where the ICE was triggered",
             vec![],
             vec![],
             vec![],
             &stacktrace,
+            &this.machine,
         );
     }
 }
diff --git a/src/eval.rs b/src/eval.rs
index 1be2a8990a6..22bbe4f816c 100644
--- a/src/eval.rs
+++ b/src/eval.rs
@@ -180,23 +180,19 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
     entry_id: DefId,
     entry_type: EntryFnType,
     config: &MiriConfig,
-) -> InterpResult<'tcx, (InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>, MPlaceTy<'tcx, Provenance>)> {
+) -> InterpResult<'tcx, (InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>, MPlaceTy<'tcx, Provenance>)>
+{
     let param_env = ty::ParamEnv::reveal_all();
     let layout_cx = LayoutCx { tcx, param_env };
     let mut ecx = InterpCx::new(
         tcx,
         rustc_span::source_map::DUMMY_SP,
         param_env,
-        Evaluator::new(config, layout_cx),
+        MiriMachine::new(config, layout_cx),
     );
 
-    // Capture the current interpreter stack state (which should be empty) so that we can emit
-    // allocation-tracking and tag-tracking diagnostics for allocations which are part of the
-    // early runtime setup.
-    let info = ecx.preprocess_diagnostics();
-
     // Some parts of initialization require a full `InterpCx`.
-    Evaluator::late_init(&mut ecx, config)?;
+    MiriMachine::late_init(&mut ecx, config)?;
 
     // Make sure we have MIR. We check MIR for some stable monomorphic function in libcore.
     let sentinel = ecx.try_resolve_path(&["core", "ascii", "escape_default"]);
@@ -324,10 +320,6 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
         }
     }
 
-    // Emit any diagnostics related to the setup process for the runtime, so that when the
-    // interpreter loop starts there are no unprocessed diagnostics.
-    ecx.process_diagnostics(info);
-
     Ok((ecx, ret_place))
 }
 
@@ -356,7 +348,6 @@ pub fn eval_entry<'tcx>(
     let res: thread::Result<InterpResult<'_, i64>> = panic::catch_unwind(AssertUnwindSafe(|| {
         // Main loop.
         loop {
-            let info = ecx.preprocess_diagnostics();
             match ecx.schedule()? {
                 SchedulingAction::ExecuteStep => {
                     assert!(ecx.step()?, "a terminated thread was scheduled for execution");
@@ -374,7 +365,6 @@ pub fn eval_entry<'tcx>(
                     break;
                 }
             }
-            ecx.process_diagnostics(info);
         }
         let return_code = ecx.read_scalar(&ret_place.into())?.to_machine_isize(&ecx)?;
         Ok(return_code)
diff --git a/src/helpers.rs b/src/helpers.rs
index 57c9fd3389c..0f0bfa355bd 100644
--- a/src/helpers.rs
+++ b/src/helpers.rs
@@ -21,7 +21,7 @@ use rand::RngCore;
 
 use crate::*;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
 // This mapping should match `decode_error_kind` in
 // <https://github.com/rust-lang/rust/blob/master/library/std/src/sys/unix/mod.rs>.
@@ -96,7 +96,7 @@ fn try_resolve_did<'tcx>(tcx: TyCtxt<'tcx>, path: &[&str]) -> Option<DefId> {
     )
 }
 
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Gets an instance for a path; fails gracefully if the path does not exist.
     fn try_resolve_path(&self, path: &[&str]) -> Option<ty::Instance<'tcx>> {
         let did = try_resolve_did(self.eval_context_ref().tcx.tcx, path)?;
@@ -391,11 +391,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         where
             F: FnMut(&MPlaceTy<'tcx, Provenance>) -> InterpResult<'tcx>,
         {
-            ecx: &'ecx MiriEvalContext<'mir, 'tcx>,
+            ecx: &'ecx MiriInterpCx<'mir, 'tcx>,
             unsafe_cell_action: F,
         }
 
-        impl<'ecx, 'mir, 'tcx: 'mir, F> ValueVisitor<'mir, 'tcx, Evaluator<'mir, 'tcx>>
+        impl<'ecx, 'mir, 'tcx: 'mir, F> ValueVisitor<'mir, 'tcx, MiriMachine<'mir, 'tcx>>
             for UnsafeCellVisitor<'ecx, 'mir, 'tcx, F>
         where
             F: FnMut(&MPlaceTy<'tcx, Provenance>) -> InterpResult<'tcx>,
@@ -403,7 +403,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
             type V = MPlaceTy<'tcx, Provenance>;
 
             #[inline(always)]
-            fn ecx(&self) -> &MiriEvalContext<'mir, 'tcx> {
+            fn ecx(&self) -> &MiriInterpCx<'mir, 'tcx> {
                 self.ecx
             }
 
@@ -508,7 +508,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 Ok(())
             }
             RejectOpWith::Warning => {
-                register_diagnostic(NonHaltingDiagnostic::RejectedIsolatedOp(op_name.to_string()));
+                this.emit_diagnostic(NonHaltingDiagnostic::RejectedIsolatedOp(op_name.to_string()));
                 Ok(())
             }
             RejectOpWith::NoWarning => Ok(()), // no warning
@@ -883,9 +883,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     }
 }
 
-impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
-    pub fn current_span(&self, tcx: TyCtxt<'tcx>) -> CurrentSpan<'_, 'mir, 'tcx> {
-        CurrentSpan { current_frame_idx: None, machine: self, tcx }
+impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
+    pub fn current_span(&self) -> CurrentSpan<'_, 'mir, 'tcx> {
+        CurrentSpan { current_frame_idx: None, machine: self }
     }
 }
 
@@ -896,11 +896,14 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
 #[derive(Clone)]
 pub struct CurrentSpan<'a, 'mir, 'tcx> {
     current_frame_idx: Option<usize>,
-    tcx: TyCtxt<'tcx>,
-    machine: &'a Evaluator<'mir, 'tcx>,
+    machine: &'a MiriMachine<'mir, 'tcx>,
 }
 
 impl<'a, 'mir: 'a, 'tcx: 'a + 'mir> CurrentSpan<'a, 'mir, 'tcx> {
+    pub fn machine(&self) -> &'a MiriMachine<'mir, 'tcx> {
+        self.machine
+    }
+
     /// Get the current span, skipping non-local frames.
     /// This function is backed by a cache, and can be assumed to be very fast.
     pub fn get(&mut self) -> Span {
@@ -916,7 +919,7 @@ impl<'a, 'mir: 'a, 'tcx: 'a + 'mir> CurrentSpan<'a, 'mir, 'tcx> {
         Self::frame_span(self.machine, idx.wrapping_sub(1))
     }
 
-    fn frame_span(machine: &Evaluator<'_, '_>, idx: usize) -> Span {
+    fn frame_span(machine: &MiriMachine<'_, '_>, idx: usize) -> Span {
         machine
             .threads
             .active_thread_stack()
@@ -928,13 +931,13 @@ impl<'a, 'mir: 'a, 'tcx: 'a + 'mir> CurrentSpan<'a, 'mir, 'tcx> {
     fn current_frame_idx(&mut self) -> usize {
         *self
             .current_frame_idx
-            .get_or_insert_with(|| Self::compute_current_frame_index(self.tcx, self.machine))
+            .get_or_insert_with(|| Self::compute_current_frame_index(self.machine))
     }
 
     // Find the position of the inner-most frame which is part of the crate being
     // compiled/executed, part of the Cargo workspace, and is also not #[track_caller].
     #[inline(never)]
-    fn compute_current_frame_index(tcx: TyCtxt<'_>, machine: &Evaluator<'_, '_>) -> usize {
+    fn compute_current_frame_index(machine: &MiriMachine<'_, '_>) -> usize {
         machine
             .threads
             .active_thread_stack()
@@ -944,7 +947,7 @@ impl<'a, 'mir: 'a, 'tcx: 'a + 'mir> CurrentSpan<'a, 'mir, 'tcx> {
             .find_map(|(idx, frame)| {
                 let def_id = frame.instance.def_id();
                 if (def_id.is_local() || machine.local_crates.contains(&def_id.krate))
-                    && !frame.instance.def.requires_caller_location(tcx)
+                    && !frame.instance.def.requires_caller_location(machine.tcx)
                 {
                     Some(idx)
                 } else {
diff --git a/src/intptrcast.rs b/src/intptrcast.rs
index 99fc086a229..b9e5def8fa7 100644
--- a/src/intptrcast.rs
+++ b/src/intptrcast.rs
@@ -59,7 +59,7 @@ impl GlobalStateInner {
 impl<'mir, 'tcx> GlobalStateInner {
     // Returns the exposed `AllocId` that corresponds to the specified addr,
     // or `None` if the addr is out of bounds
-    fn alloc_id_from_addr(ecx: &MiriEvalContext<'mir, 'tcx>, addr: u64) -> Option<AllocId> {
+    fn alloc_id_from_addr(ecx: &MiriInterpCx<'mir, 'tcx>, addr: u64) -> Option<AllocId> {
         let global_state = ecx.machine.intptrcast.borrow();
         assert!(global_state.provenance_mode != ProvenanceMode::Strict);
 
@@ -97,7 +97,7 @@ impl<'mir, 'tcx> GlobalStateInner {
     }
 
     pub fn expose_ptr(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         alloc_id: AllocId,
         sb: SbTag,
     ) -> InterpResult<'tcx> {
@@ -114,7 +114,7 @@ impl<'mir, 'tcx> GlobalStateInner {
     }
 
     pub fn ptr_from_addr_transmute(
-        _ecx: &MiriEvalContext<'mir, 'tcx>,
+        _ecx: &MiriInterpCx<'mir, 'tcx>,
         addr: u64,
     ) -> Pointer<Option<Provenance>> {
         trace!("Transmuting {:#x} to a pointer", addr);
@@ -124,7 +124,7 @@ impl<'mir, 'tcx> GlobalStateInner {
     }
 
     pub fn ptr_from_addr_cast(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         addr: u64,
     ) -> InterpResult<'tcx, Pointer<Option<Provenance>>> {
         trace!("Casting {:#x} to a pointer", addr);
@@ -142,7 +142,7 @@ impl<'mir, 'tcx> GlobalStateInner {
                     let first = past_warnings.is_empty();
                     if past_warnings.insert(ecx.cur_span()) {
                         // Newly inserted, so first time we see this span.
-                        register_diagnostic(NonHaltingDiagnostic::Int2Ptr { details: first });
+                        ecx.emit_diagnostic(NonHaltingDiagnostic::Int2Ptr { details: first });
                     }
                 });
             }
@@ -156,7 +156,7 @@ impl<'mir, 'tcx> GlobalStateInner {
         Ok(Pointer::new(Some(Provenance::Wildcard), Size::from_bytes(addr)))
     }
 
-    fn alloc_base_addr(ecx: &MiriEvalContext<'mir, 'tcx>, alloc_id: AllocId) -> u64 {
+    fn alloc_base_addr(ecx: &MiriInterpCx<'mir, 'tcx>, alloc_id: AllocId) -> u64 {
         let mut global_state = ecx.machine.intptrcast.borrow_mut();
         let global_state = &mut *global_state;
 
@@ -202,7 +202,7 @@ impl<'mir, 'tcx> GlobalStateInner {
     }
 
     /// Convert a relative (tcx) pointer to an absolute address.
-    pub fn rel_ptr_to_addr(ecx: &MiriEvalContext<'mir, 'tcx>, ptr: Pointer<AllocId>) -> u64 {
+    pub fn rel_ptr_to_addr(ecx: &MiriInterpCx<'mir, 'tcx>, ptr: Pointer<AllocId>) -> u64 {
         let (alloc_id, offset) = ptr.into_parts(); // offset is relative (AllocId provenance)
         let base_addr = GlobalStateInner::alloc_base_addr(ecx, alloc_id);
 
@@ -214,7 +214,7 @@ impl<'mir, 'tcx> GlobalStateInner {
     /// When a pointer is used for a memory access, this computes where in which allocation the
     /// access is going.
     pub fn abs_ptr_to_rel(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         ptr: Pointer<Provenance>,
     ) -> Option<(AllocId, Size)> {
         let (tag, addr) = ptr.into_parts(); // addr is absolute (Tag provenance)
diff --git a/src/lib.rs b/src/lib.rs
index 9b3be6128ca..6006d6c89db 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -94,8 +94,8 @@ pub use crate::concurrency::{
     },
 };
 pub use crate::diagnostics::{
-    register_diagnostic, report_error, EvalContextExt as DiagnosticsEvalContextExt,
-    NonHaltingDiagnostic, TerminationInfo,
+    report_error, EvalContextExt as DiagnosticsEvalContextExt, NonHaltingDiagnostic,
+    TerminationInfo,
 };
 pub use crate::eval::{
     create_ecx, eval_entry, AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, RejectOpWith,
@@ -103,8 +103,8 @@ pub use crate::eval::{
 pub use crate::helpers::{CurrentSpan, EvalContextExt as HelpersEvalContextExt};
 pub use crate::intptrcast::ProvenanceMode;
 pub use crate::machine::{
-    AllocExtra, Evaluator, FrameData, MiriEvalContext, MiriEvalContextExt, MiriMemoryKind,
-    Provenance, ProvenanceExtra, NUM_CPUS, PAGE_SIZE, STACK_ADDR, STACK_SIZE,
+    AllocExtra, FrameData, MiriInterpCx, MiriInterpCxExt, MiriMachine, MiriMemoryKind, Provenance,
+    ProvenanceExtra, NUM_CPUS, PAGE_SIZE, STACK_ADDR, STACK_SIZE,
 };
 pub use crate::mono_hash_map::MonoHashMap;
 pub use crate::operator::EvalContextExt as OperatorEvalContextExt;
diff --git a/src/machine.rs b/src/machine.rs
index bd2c4300465..8db546463c2 100644
--- a/src/machine.rs
+++ b/src/machine.rs
@@ -291,9 +291,17 @@ impl<'mir, 'tcx: 'mir> PrimitiveLayouts<'tcx> {
 }
 
 /// The machine itself.
-pub struct Evaluator<'mir, 'tcx> {
+pub struct MiriMachine<'mir, 'tcx> {
+    // We carry a copy of the global `TyCtxt` for convenience, so methods taking just `&Evaluator` have `tcx` access.
+    pub tcx: TyCtxt<'tcx>,
+
+    /// Stacked Borrows global data.
     pub stacked_borrows: Option<stacked_borrows::GlobalState>,
+
+    /// Data race detector global data.
     pub data_race: Option<data_race::GlobalState>,
+
+    /// Ptr-int-cast module global data.
     pub intptrcast: intptrcast::GlobalState,
 
     /// Environment variables set by `setenv`.
@@ -400,7 +408,7 @@ pub struct Evaluator<'mir, 'tcx> {
     pub(crate) since_gc: u32,
 }
 
-impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
+impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
     pub(crate) fn new(config: &MiriConfig, layout_cx: LayoutCx<'tcx, TyCtxt<'tcx>>) -> Self {
         let target_triple = &layout_cx.tcx.sess.opts.target_triple.to_string();
         let local_crates = helpers::get_local_crates(layout_cx.tcx);
@@ -418,7 +426,8 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
             ))
         });
         let data_race = config.data_race_detector.then(|| data_race::GlobalState::new(config));
-        Evaluator {
+        MiriMachine {
+            tcx: layout_cx.tcx,
             stacked_borrows,
             data_race,
             intptrcast: RefCell::new(intptrcast::GlobalStateInner::new(config)),
@@ -479,17 +488,17 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
     }
 
     pub(crate) fn late_init(
-        this: &mut MiriEvalContext<'mir, 'tcx>,
+        this: &mut MiriInterpCx<'mir, 'tcx>,
         config: &MiriConfig,
     ) -> InterpResult<'tcx> {
         EnvVars::init(this, config)?;
-        Evaluator::init_extern_statics(this)?;
+        MiriMachine::init_extern_statics(this)?;
         ThreadManager::init(this);
         Ok(())
     }
 
     fn add_extern_static(
-        this: &mut MiriEvalContext<'mir, 'tcx>,
+        this: &mut MiriInterpCx<'mir, 'tcx>,
         name: &str,
         ptr: Pointer<Option<Provenance>>,
     ) {
@@ -499,7 +508,7 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
     }
 
     fn alloc_extern_static(
-        this: &mut MiriEvalContext<'mir, 'tcx>,
+        this: &mut MiriInterpCx<'mir, 'tcx>,
         name: &str,
         val: ImmTy<'tcx, Provenance>,
     ) -> InterpResult<'tcx> {
@@ -510,7 +519,7 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
     }
 
     /// Sets up the "extern statics" for this machine.
-    fn init_extern_statics(this: &mut MiriEvalContext<'mir, 'tcx>) -> InterpResult<'tcx> {
+    fn init_extern_statics(this: &mut MiriInterpCx<'mir, 'tcx>) -> InterpResult<'tcx> {
         match this.tcx.sess.target.os.as_ref() {
             "linux" => {
                 // "environ"
@@ -576,26 +585,26 @@ impl<'mir, 'tcx> Evaluator<'mir, 'tcx> {
 }
 
 /// A rustc InterpCx for Miri.
-pub type MiriEvalContext<'mir, 'tcx> = InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>;
+pub type MiriInterpCx<'mir, 'tcx> = InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>;
 
 /// A little trait that's useful to be inherited by extension traits.
-pub trait MiriEvalContextExt<'mir, 'tcx> {
-    fn eval_context_ref<'a>(&'a self) -> &'a MiriEvalContext<'mir, 'tcx>;
-    fn eval_context_mut<'a>(&'a mut self) -> &'a mut MiriEvalContext<'mir, 'tcx>;
+pub trait MiriInterpCxExt<'mir, 'tcx> {
+    fn eval_context_ref<'a>(&'a self) -> &'a MiriInterpCx<'mir, 'tcx>;
+    fn eval_context_mut<'a>(&'a mut self) -> &'a mut MiriInterpCx<'mir, 'tcx>;
 }
-impl<'mir, 'tcx> MiriEvalContextExt<'mir, 'tcx> for MiriEvalContext<'mir, 'tcx> {
+impl<'mir, 'tcx> MiriInterpCxExt<'mir, 'tcx> for MiriInterpCx<'mir, 'tcx> {
     #[inline(always)]
-    fn eval_context_ref(&self) -> &MiriEvalContext<'mir, 'tcx> {
+    fn eval_context_ref(&self) -> &MiriInterpCx<'mir, 'tcx> {
         self
     }
     #[inline(always)]
-    fn eval_context_mut(&mut self) -> &mut MiriEvalContext<'mir, 'tcx> {
+    fn eval_context_mut(&mut self) -> &mut MiriInterpCx<'mir, 'tcx> {
         self
     }
 }
 
 /// Machine hook implementations.
-impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
+impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
     type MemoryKind = MiriMemoryKind;
     type ExtraFnVal = Dlsym;
 
@@ -615,33 +624,33 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     const PANIC_ON_ALLOC_FAIL: bool = false;
 
     #[inline(always)]
-    fn enforce_alignment(ecx: &MiriEvalContext<'mir, 'tcx>) -> bool {
+    fn enforce_alignment(ecx: &MiriInterpCx<'mir, 'tcx>) -> bool {
         ecx.machine.check_alignment != AlignmentCheck::None
     }
 
     #[inline(always)]
-    fn use_addr_for_alignment_check(ecx: &MiriEvalContext<'mir, 'tcx>) -> bool {
+    fn use_addr_for_alignment_check(ecx: &MiriInterpCx<'mir, 'tcx>) -> bool {
         ecx.machine.check_alignment == AlignmentCheck::Int
     }
 
     #[inline(always)]
-    fn enforce_validity(ecx: &MiriEvalContext<'mir, 'tcx>) -> bool {
+    fn enforce_validity(ecx: &MiriInterpCx<'mir, 'tcx>) -> bool {
         ecx.machine.validate
     }
 
     #[inline(always)]
-    fn enforce_abi(ecx: &MiriEvalContext<'mir, 'tcx>) -> bool {
+    fn enforce_abi(ecx: &MiriInterpCx<'mir, 'tcx>) -> bool {
         ecx.machine.enforce_abi
     }
 
     #[inline(always)]
-    fn checked_binop_checks_overflow(ecx: &MiriEvalContext<'mir, 'tcx>) -> bool {
+    fn checked_binop_checks_overflow(ecx: &MiriInterpCx<'mir, 'tcx>) -> bool {
         ecx.tcx.sess.overflow_checks()
     }
 
     #[inline(always)]
     fn find_mir_or_eval_fn(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         instance: ty::Instance<'tcx>,
         abi: Abi,
         args: &[OpTy<'tcx, Provenance>],
@@ -654,7 +663,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn call_extra_fn(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         fn_val: Dlsym,
         abi: Abi,
         args: &[OpTy<'tcx, Provenance>],
@@ -667,7 +676,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn call_intrinsic(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         instance: ty::Instance<'tcx>,
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
@@ -679,7 +688,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn assert_panic(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         msg: &mir::AssertMessage<'tcx>,
         unwind: Option<mir::BasicBlock>,
     ) -> InterpResult<'tcx> {
@@ -687,13 +696,13 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     }
 
     #[inline(always)]
-    fn abort(_ecx: &mut MiriEvalContext<'mir, 'tcx>, msg: String) -> InterpResult<'tcx, !> {
+    fn abort(_ecx: &mut MiriInterpCx<'mir, 'tcx>, msg: String) -> InterpResult<'tcx, !> {
         throw_machine_stop!(TerminationInfo::Abort(msg))
     }
 
     #[inline(always)]
     fn binary_ptr_op(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         bin_op: mir::BinOp,
         left: &ImmTy<'tcx, Provenance>,
         right: &ImmTy<'tcx, Provenance>,
@@ -702,14 +711,14 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     }
 
     fn thread_local_static_base_pointer(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         def_id: DefId,
     ) -> InterpResult<'tcx, Pointer<Provenance>> {
         ecx.get_or_create_thread_local_alloc(def_id)
     }
 
     fn extern_static_base_pointer(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         def_id: DefId,
     ) -> InterpResult<'tcx, Pointer<Provenance>> {
         let link_name = ecx.item_link_name(def_id);
@@ -748,14 +757,14 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     }
 
     fn adjust_allocation<'b>(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         id: AllocId,
         alloc: Cow<'b, Allocation>,
         kind: Option<MemoryKind<Self::MemoryKind>>,
     ) -> InterpResult<'tcx, Cow<'b, Allocation<Self::Provenance, Self::AllocExtra>>> {
         let kind = kind.expect("we set our STATIC_KIND so this cannot be None");
         if ecx.machine.tracked_alloc_ids.contains(&id) {
-            register_diagnostic(NonHaltingDiagnostic::CreatedAlloc(
+            ecx.emit_diagnostic(NonHaltingDiagnostic::CreatedAlloc(
                 id,
                 alloc.size(),
                 alloc.align,
@@ -770,7 +779,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
                 alloc.size(),
                 stacked_borrows,
                 kind,
-                ecx.machine.current_span(*ecx.tcx),
+                ecx.machine.current_span(),
             )
         });
         let race_alloc = ecx.machine.data_race.as_ref().map(|data_race| {
@@ -795,7 +804,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     }
 
     fn adjust_alloc_base_pointer(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         ptr: Pointer<AllocId>,
     ) -> Pointer<Provenance> {
         if cfg!(debug_assertions) {
@@ -813,7 +822,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
         }
         let absolute_addr = intptrcast::GlobalStateInner::rel_ptr_to_addr(ecx, ptr);
         let sb_tag = if let Some(stacked_borrows) = &ecx.machine.stacked_borrows {
-            stacked_borrows.borrow_mut().base_ptr_tag(ptr.provenance)
+            stacked_borrows.borrow_mut().base_ptr_tag(ptr.provenance, &ecx.machine)
         } else {
             // Value does not matter, SB is disabled
             SbTag::default()
@@ -826,7 +835,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn ptr_from_addr_cast(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         addr: u64,
     ) -> InterpResult<'tcx, Pointer<Option<Self::Provenance>>> {
         intptrcast::GlobalStateInner::ptr_from_addr_cast(ecx, addr)
@@ -850,7 +859,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
     /// Convert a pointer with provenance into an allocation-offset pair,
     /// or a `None` with an absolute address if that conversion is not possible.
     fn ptr_get_alloc(
-        ecx: &MiriEvalContext<'mir, 'tcx>,
+        ecx: &MiriInterpCx<'mir, 'tcx>,
         ptr: Pointer<Self::Provenance>,
     ) -> Option<(AllocId, Size, Self::ProvenanceExtra)> {
         let rel = intptrcast::GlobalStateInner::abs_ptr_to_rel(ecx, ptr);
@@ -866,7 +875,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn before_memory_read(
-        tcx: TyCtxt<'tcx>,
+        _tcx: TyCtxt<'tcx>,
         machine: &Self,
         alloc_extra: &AllocExtra,
         (alloc_id, prov_extra): (AllocId, Self::ProvenanceExtra),
@@ -886,7 +895,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
                 prov_extra,
                 range,
                 machine.stacked_borrows.as_ref().unwrap(),
-                machine.current_span(tcx),
+                machine.current_span(),
                 &machine.threads,
             )?;
         }
@@ -898,7 +907,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn before_memory_write(
-        tcx: TyCtxt<'tcx>,
+        _tcx: TyCtxt<'tcx>,
         machine: &mut Self,
         alloc_extra: &mut AllocExtra,
         (alloc_id, prov_extra): (AllocId, Self::ProvenanceExtra),
@@ -918,7 +927,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
                 prov_extra,
                 range,
                 machine.stacked_borrows.as_ref().unwrap(),
-                machine.current_span(tcx),
+                machine.current_span(),
                 &machine.threads,
             )?;
         }
@@ -930,14 +939,14 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
 
     #[inline(always)]
     fn before_memory_deallocation(
-        tcx: TyCtxt<'tcx>,
+        _tcx: TyCtxt<'tcx>,
         machine: &mut Self,
         alloc_extra: &mut AllocExtra,
         (alloc_id, prove_extra): (AllocId, Self::ProvenanceExtra),
         range: AllocRange,
     ) -> InterpResult<'tcx> {
         if machine.tracked_alloc_ids.contains(&alloc_id) {
-            register_diagnostic(NonHaltingDiagnostic::FreedAlloc(alloc_id));
+            machine.emit_diagnostic(NonHaltingDiagnostic::FreedAlloc(alloc_id));
         }
         if let Some(data_race) = &mut alloc_extra.data_race {
             data_race.deallocate(
@@ -953,7 +962,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
                 prove_extra,
                 range,
                 machine.stacked_borrows.as_ref().unwrap(),
-                machine.current_span(tcx),
+                machine.current_span(),
                 &machine.threads,
             )
         } else {
@@ -993,7 +1002,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
         let stacked_borrows = ecx.machine.stacked_borrows.as_ref();
 
         let extra = FrameData {
-            stacked_borrows: stacked_borrows.map(|sb| sb.borrow_mut().new_frame()),
+            stacked_borrows: stacked_borrows.map(|sb| sb.borrow_mut().new_frame(&ecx.machine)),
             catch_unwind: None,
             timing,
         };
@@ -1018,7 +1027,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'mir, 'tcx> {
         // Possibly report our progress.
         if let Some(report_progress) = ecx.machine.report_progress {
             if ecx.machine.basic_block_count % u64::from(report_progress) == 0 {
-                register_diagnostic(NonHaltingDiagnostic::ProgressReport {
+                ecx.emit_diagnostic(NonHaltingDiagnostic::ProgressReport {
                     block_count: ecx.machine.basic_block_count,
                 });
             }
diff --git a/src/operator.rs b/src/operator.rs
index 09e9b0cbd15..a0ef7fcad16 100644
--- a/src/operator.rs
+++ b/src/operator.rs
@@ -14,7 +14,7 @@ pub trait EvalContextExt<'tcx> {
     ) -> InterpResult<'tcx, (Scalar<Provenance>, bool, Ty<'tcx>)>;
 }
 
-impl<'mir, 'tcx> EvalContextExt<'tcx> for super::MiriEvalContext<'mir, 'tcx> {
+impl<'mir, 'tcx> EvalContextExt<'tcx> for super::MiriInterpCx<'mir, 'tcx> {
     fn binary_ptr_op(
         &self,
         bin_op: mir::BinOp,
diff --git a/src/shims/backtrace.rs b/src/shims/backtrace.rs
index bce4961339c..15987eee537 100644
--- a/src/shims/backtrace.rs
+++ b/src/shims/backtrace.rs
@@ -5,8 +5,8 @@ use rustc_middle::ty::{self, Instance};
 use rustc_span::{BytePos, Loc, Symbol};
 use rustc_target::{abi::Size, spec::abi::Abi};
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn handle_miri_backtrace_size(
         &mut self,
         abi: Abi,
diff --git a/src/shims/dlsym.rs b/src/shims/dlsym.rs
index 5cb3c99e3d1..8bf6d24f85f 100644
--- a/src/shims/dlsym.rs
+++ b/src/shims/dlsym.rs
@@ -27,8 +27,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/env.rs b/src/shims/env.rs
index 084433fab74..638c18934bd 100644
--- a/src/shims/env.rs
+++ b/src/shims/env.rs
@@ -38,7 +38,7 @@ pub struct EnvVars<'tcx> {
 
 impl<'tcx> EnvVars<'tcx> {
     pub(crate) fn init<'mir>(
-        ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+        ecx: &mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>,
         config: &MiriConfig,
     ) -> InterpResult<'tcx> {
         let target_os = ecx.tcx.sess.target.os.as_ref();
@@ -74,7 +74,7 @@ impl<'tcx> EnvVars<'tcx> {
     }
 
     pub(crate) fn cleanup<'mir>(
-        ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+        ecx: &mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>,
     ) -> InterpResult<'tcx> {
         // Deallocate individual env vars.
         let env_vars = mem::take(&mut ecx.machine.env_vars.map);
@@ -92,7 +92,7 @@ impl<'tcx> EnvVars<'tcx> {
 fn alloc_env_var_as_c_str<'mir, 'tcx>(
     name: &OsStr,
     value: &OsStr,
-    ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+    ecx: &mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>,
 ) -> InterpResult<'tcx, Pointer<Option<Provenance>>> {
     let mut name_osstring = name.to_os_string();
     name_osstring.push("=");
@@ -103,7 +103,7 @@ fn alloc_env_var_as_c_str<'mir, 'tcx>(
 fn alloc_env_var_as_wide_str<'mir, 'tcx>(
     name: &OsStr,
     value: &OsStr,
-    ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>,
+    ecx: &mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>,
 ) -> InterpResult<'tcx, Pointer<Option<Provenance>>> {
     let mut name_osstring = name.to_os_string();
     name_osstring.push("=");
@@ -111,8 +111,8 @@ fn alloc_env_var_as_wide_str<'mir, 'tcx>(
     ecx.alloc_os_str_as_wide_str(name_osstring.as_os_str(), MiriMemoryKind::Runtime.into())
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn getenv(
         &mut self,
         name_op: &OpTy<'tcx, Provenance>,
diff --git a/src/shims/ffi_support.rs b/src/shims/ffi_support.rs
index 844bcb40d53..0813554e9d2 100644
--- a/src/shims/ffi_support.rs
+++ b/src/shims/ffi_support.rs
@@ -7,9 +7,9 @@ use rustc_target::abi::HasDataLayout;
 
 use crate::*;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Extract the scalar value from the result of reading a scalar from the machine,
     /// and convert it to a `CArg`.
     fn scalar_to_carg(
diff --git a/src/shims/foreign_items.rs b/src/shims/foreign_items.rs
index b94b6bbb2b8..6d052083d37 100644
--- a/src/shims/foreign_items.rs
+++ b/src/shims/foreign_items.rs
@@ -38,8 +38,8 @@ pub enum EmulateByNameResult<'mir, 'tcx> {
     NotSupported,
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Returns the minimum alignment for the target architecture for allocations of the given size.
     fn min_align(&self, size: u64, kind: MiriMemoryKind) -> Align {
         let this = self.eval_context_ref();
@@ -334,7 +334,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     fn emulate_allocator(
         &mut self,
         symbol: Symbol,
-        default: impl FnOnce(&mut MiriEvalContext<'mir, 'tcx>) -> InterpResult<'tcx>,
+        default: impl FnOnce(&mut MiriInterpCx<'mir, 'tcx>) -> InterpResult<'tcx>,
     ) -> InterpResult<'tcx, EmulateByNameResult<'mir, 'tcx>> {
         let this = self.eval_context_mut();
 
diff --git a/src/shims/intrinsics/atomic.rs b/src/shims/intrinsics/atomic.rs
index 86f132f73fc..50f69bdca36 100644
--- a/src/shims/intrinsics/atomic.rs
+++ b/src/shims/intrinsics/atomic.rs
@@ -11,8 +11,8 @@ pub enum AtomicOp {
     Min,
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Calls the atomic intrinsic `intrinsic`; the `atomic_` prefix has already been removed.
     fn emulate_atomic_intrinsic(
         &mut self,
@@ -119,8 +119,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for MiriEvalContext<'mir, 'tcx> {}
-trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextPrivExt<'mir, 'tcx: 'mir>: MiriInterpCxExt<'mir, 'tcx> {
     fn atomic_load(
         &mut self,
         args: &[OpTy<'tcx, Provenance>],
diff --git a/src/shims/intrinsics/mod.rs b/src/shims/intrinsics/mod.rs
index ac1642b0065..b85c799e2da 100644
--- a/src/shims/intrinsics/mod.rs
+++ b/src/shims/intrinsics/mod.rs
@@ -18,8 +18,8 @@ use atomic::EvalContextExt as _;
 use helpers::check_arg_count;
 use simd::EvalContextExt as _;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_intrinsic(
         &mut self,
         instance: ty::Instance<'tcx>,
diff --git a/src/shims/intrinsics/simd.rs b/src/shims/intrinsics/simd.rs
index 1698477cbde..163d185f66f 100644
--- a/src/shims/intrinsics/simd.rs
+++ b/src/shims/intrinsics/simd.rs
@@ -6,8 +6,8 @@ use rustc_target::abi::{Endian, HasDataLayout, Size};
 use crate::*;
 use helpers::check_arg_count;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Calls the simd intrinsic `intrinsic`; the `simd_` prefix has already been removed.
     fn emulate_simd_intrinsic(
         &mut self,
diff --git a/src/shims/mod.rs b/src/shims/mod.rs
index ee2145db7e1..93083b486bf 100644
--- a/src/shims/mod.rs
+++ b/src/shims/mod.rs
@@ -24,8 +24,8 @@ use rustc_target::spec::abi::Abi;
 use crate::*;
 use helpers::check_arg_count;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn find_mir_or_eval_fn(
         &mut self,
         instance: ty::Instance<'tcx>,
diff --git a/src/shims/os_str.rs b/src/shims/os_str.rs
index 6ca09f3fcad..407dab970ad 100644
--- a/src/shims/os_str.rs
+++ b/src/shims/os_str.rs
@@ -46,8 +46,8 @@ pub fn bytes_to_os_str<'a, 'tcx>(bytes: &'a [u8]) -> InterpResult<'tcx, &'a OsSt
     Ok(OsStr::new(s))
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Helper function to read an OsString from a null-terminated sequence of bytes, which is what
     /// the Unix APIs usually handle.
     fn read_os_str_from_c_str<'a>(
diff --git a/src/shims/panic.rs b/src/shims/panic.rs
index 3784dabfeac..2e8245acf4a 100644
--- a/src/shims/panic.rs
+++ b/src/shims/panic.rs
@@ -35,8 +35,8 @@ pub struct CatchUnwindData<'tcx> {
     ret: mir::BasicBlock,
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Handles the special `miri_start_panic` intrinsic, which is called
     /// by libpanic_unwind to delegate the actual unwinding process to Miri.
     fn handle_miri_start_panic(
diff --git a/src/shims/time.rs b/src/shims/time.rs
index f083ab49900..24fe5245393 100644
--- a/src/shims/time.rs
+++ b/src/shims/time.rs
@@ -8,8 +8,8 @@ pub fn system_time_to_duration<'tcx>(time: &SystemTime) -> InterpResult<'tcx, Du
         .map_err(|_| err_unsup_format!("times before the Unix epoch are not supported").into())
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn clock_gettime(
         &mut self,
         clk_id_op: &OpTy<'tcx, Provenance>,
diff --git a/src/shims/tls.rs b/src/shims/tls.rs
index 343fa05712d..d93d6a16a07 100644
--- a/src/shims/tls.rs
+++ b/src/shims/tls.rs
@@ -241,8 +241,8 @@ impl<'tcx> TlsData<'tcx> {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-trait EvalContextPrivExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextPrivExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextPrivExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Schedule TLS destructors for Windows.
     /// On windows, TLS destructors are managed by std.
     fn schedule_windows_tls_dtors(&mut self) -> InterpResult<'tcx> {
@@ -346,8 +346,8 @@ trait EvalContextPrivExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Schedule an active thread's TLS destructor to run on the active thread.
     /// Note that this function does not run the destructors itself, it just
     /// schedules them one by one each time it is called and reenables the
diff --git a/src/shims/unix/android/dlsym.rs b/src/shims/unix/android/dlsym.rs
index 28941a3de4e..4cb78d4dabd 100644
--- a/src/shims/unix/android/dlsym.rs
+++ b/src/shims/unix/android/dlsym.rs
@@ -21,8 +21,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/unix/android/foreign_items.rs b/src/shims/unix/android/foreign_items.rs
index 9c12736887f..756aed369f1 100644
--- a/src/shims/unix/android/foreign_items.rs
+++ b/src/shims/unix/android/foreign_items.rs
@@ -4,9 +4,9 @@ use rustc_target::spec::abi::Abi;
 use crate::*;
 use shims::foreign_items::EmulateByNameResult;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
diff --git a/src/shims/unix/dlsym.rs b/src/shims/unix/dlsym.rs
index fee12822917..8bc19d18f2b 100644
--- a/src/shims/unix/dlsym.rs
+++ b/src/shims/unix/dlsym.rs
@@ -29,8 +29,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/unix/foreign_items.rs b/src/shims/unix/foreign_items.rs
index 09604e178e2..153e5852dcc 100644
--- a/src/shims/unix/foreign_items.rs
+++ b/src/shims/unix/foreign_items.rs
@@ -13,8 +13,8 @@ use shims::unix::fs::EvalContextExt as _;
 use shims::unix::sync::EvalContextExt as _;
 use shims::unix::thread::EvalContextExt as _;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
@@ -228,7 +228,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
 
                 // FIXME: Which of these are POSIX, and which are GNU/Linux?
                 // At least the names seem to all also exist on macOS.
-                let sysconfs: &[(&str, fn(&MiriEvalContext<'_, '_>) -> Scalar<Provenance>)] = &[
+                let sysconfs: &[(&str, fn(&MiriInterpCx<'_, '_>) -> Scalar<Provenance>)] = &[
                     ("_SC_PAGESIZE", |this| Scalar::from_int(PAGE_SIZE, this.pointer_size())),
                     ("_SC_NPROCESSORS_CONF", |this| Scalar::from_int(NUM_CPUS, this.pointer_size())),
                     ("_SC_NPROCESSORS_ONLN", |this| Scalar::from_int(NUM_CPUS, this.pointer_size())),
diff --git a/src/shims/unix/freebsd/dlsym.rs b/src/shims/unix/freebsd/dlsym.rs
index ebc1998f1b5..d759ffb8994 100644
--- a/src/shims/unix/freebsd/dlsym.rs
+++ b/src/shims/unix/freebsd/dlsym.rs
@@ -14,8 +14,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/unix/freebsd/foreign_items.rs b/src/shims/unix/freebsd/foreign_items.rs
index 73464cdacb0..70798f98174 100644
--- a/src/shims/unix/freebsd/foreign_items.rs
+++ b/src/shims/unix/freebsd/foreign_items.rs
@@ -5,9 +5,9 @@ use crate::*;
 use shims::foreign_items::EmulateByNameResult;
 use shims::unix::thread::EvalContextExt as _;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
diff --git a/src/shims/unix/fs.rs b/src/shims/unix/fs.rs
index 06cd533626a..edeb2001f93 100644
--- a/src/shims/unix/fs.rs
+++ b/src/shims/unix/fs.rs
@@ -304,8 +304,8 @@ impl FileHandler {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExtPrivate<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-trait EvalContextExtPrivate<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExtPrivate<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextExtPrivate<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn macos_stat_write_buf(
         &mut self,
         metadata: FileMetadata,
@@ -478,8 +478,8 @@ fn maybe_sync_file(
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn open(&mut self, args: &[OpTy<'tcx, Provenance>]) -> InterpResult<'tcx, i32> {
         if args.len() < 2 {
             throw_ub_format!(
@@ -1892,7 +1892,7 @@ struct FileMetadata {
 
 impl FileMetadata {
     fn from_path<'tcx, 'mir>(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         path: &Path,
         follow_symlink: bool,
     ) -> InterpResult<'tcx, Option<FileMetadata>> {
@@ -1903,7 +1903,7 @@ impl FileMetadata {
     }
 
     fn from_fd<'tcx, 'mir>(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         fd: i32,
     ) -> InterpResult<'tcx, Option<FileMetadata>> {
         let option = ecx.machine.file_handler.handles.get(&fd);
@@ -1917,7 +1917,7 @@ impl FileMetadata {
     }
 
     fn from_meta<'tcx, 'mir>(
-        ecx: &mut MiriEvalContext<'mir, 'tcx>,
+        ecx: &mut MiriInterpCx<'mir, 'tcx>,
         metadata: Result<std::fs::Metadata, std::io::Error>,
     ) -> InterpResult<'tcx, Option<FileMetadata>> {
         let metadata = match metadata {
diff --git a/src/shims/unix/linux/dlsym.rs b/src/shims/unix/linux/dlsym.rs
index f5cf1e0071a..a96c14c142b 100644
--- a/src/shims/unix/linux/dlsym.rs
+++ b/src/shims/unix/linux/dlsym.rs
@@ -18,8 +18,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/unix/linux/foreign_items.rs b/src/shims/unix/linux/foreign_items.rs
index afa0591a3c9..5d000f9d121 100644
--- a/src/shims/unix/linux/foreign_items.rs
+++ b/src/shims/unix/linux/foreign_items.rs
@@ -8,8 +8,8 @@ use shims::unix::linux::sync::futex;
 use shims::unix::sync::EvalContextExt as _;
 use shims::unix::thread::EvalContextExt as _;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
@@ -167,7 +167,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
 
 // Shims the linux `getrandom` syscall.
 fn getrandom<'tcx>(
-    this: &mut MiriEvalContext<'_, 'tcx>,
+    this: &mut MiriInterpCx<'_, 'tcx>,
     ptr: &OpTy<'tcx, Provenance>,
     len: &OpTy<'tcx, Provenance>,
     flags: &OpTy<'tcx, Provenance>,
diff --git a/src/shims/unix/linux/sync.rs b/src/shims/unix/linux/sync.rs
index cf5a945c5fa..5a6ce28d25c 100644
--- a/src/shims/unix/linux/sync.rs
+++ b/src/shims/unix/linux/sync.rs
@@ -6,7 +6,7 @@ use std::time::SystemTime;
 /// Implementation of the SYS_futex syscall.
 /// `args` is the arguments *after* the syscall number.
 pub fn futex<'tcx>(
-    this: &mut MiriEvalContext<'_, 'tcx>,
+    this: &mut MiriInterpCx<'_, 'tcx>,
     args: &[OpTy<'tcx, Provenance>],
     dest: &PlaceTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx> {
diff --git a/src/shims/unix/macos/dlsym.rs b/src/shims/unix/macos/dlsym.rs
index f21f1ae9af6..18804b45efc 100644
--- a/src/shims/unix/macos/dlsym.rs
+++ b/src/shims/unix/macos/dlsym.rs
@@ -22,8 +22,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/unix/macos/foreign_items.rs b/src/shims/unix/macos/foreign_items.rs
index 9ad2ef47e09..38d791fba98 100644
--- a/src/shims/unix/macos/foreign_items.rs
+++ b/src/shims/unix/macos/foreign_items.rs
@@ -6,8 +6,8 @@ use shims::foreign_items::EmulateByNameResult;
 use shims::unix::fs::EvalContextExt as _;
 use shims::unix::thread::EvalContextExt as _;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
diff --git a/src/shims/unix/sync.rs b/src/shims/unix/sync.rs
index 8d9487b04de..2e972a27ffe 100644
--- a/src/shims/unix/sync.rs
+++ b/src/shims/unix/sync.rs
@@ -20,14 +20,14 @@ use crate::*;
 const PTHREAD_MUTEX_NORMAL_FLAG: i32 = 0x8000000;
 
 fn is_mutex_kind_default<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     kind: Scalar<Provenance>,
 ) -> InterpResult<'tcx, bool> {
     Ok(kind == ecx.eval_libc("PTHREAD_MUTEX_DEFAULT")?)
 }
 
 fn is_mutex_kind_normal<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     kind: Scalar<Provenance>,
 ) -> InterpResult<'tcx, bool> {
     let kind = kind.to_i32()?;
@@ -36,14 +36,14 @@ fn is_mutex_kind_normal<'mir, 'tcx: 'mir>(
 }
 
 fn mutexattr_get_kind<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     attr_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset(attr_op, 0, ecx.machine.layouts.i32)
 }
 
 fn mutexattr_set_kind<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     attr_op: &OpTy<'tcx, Provenance>,
     kind: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -60,7 +60,7 @@ fn mutexattr_set_kind<'mir, 'tcx: 'mir>(
 // (the kind has to be at its offset for compatibility with static initializer macros)
 
 fn mutex_get_kind<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     let offset = if ecx.pointer_size().bytes() == 8 { 16 } else { 12 };
@@ -73,7 +73,7 @@ fn mutex_get_kind<'mir, 'tcx: 'mir>(
 }
 
 fn mutex_set_kind<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
     kind: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -88,14 +88,14 @@ fn mutex_set_kind<'mir, 'tcx: 'mir>(
 }
 
 fn mutex_get_id<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset_atomic(mutex_op, 4, ecx.machine.layouts.u32, AtomicReadOrd::Relaxed)
 }
 
 fn mutex_set_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
     id: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -109,7 +109,7 @@ fn mutex_set_id<'mir, 'tcx: 'mir>(
 }
 
 fn mutex_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, MutexId> {
     let value_place = ecx.deref_operand_and_offset(mutex_op, 4, ecx.machine.layouts.u32)?;
@@ -143,14 +143,14 @@ fn mutex_get_or_create_id<'mir, 'tcx: 'mir>(
 // bytes 4-7: rwlock id as u32 or 0 if id is not assigned yet.
 
 fn rwlock_get_id<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     rwlock_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset_atomic(rwlock_op, 4, ecx.machine.layouts.u32, AtomicReadOrd::Relaxed)
 }
 
 fn rwlock_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     rwlock_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, RwLockId> {
     let value_place = ecx.deref_operand_and_offset(rwlock_op, 4, ecx.machine.layouts.u32)?;
@@ -183,14 +183,14 @@ fn rwlock_get_or_create_id<'mir, 'tcx: 'mir>(
 // (e.g. CLOCK_REALTIME).
 
 fn condattr_get_clock_id<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     attr_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset(attr_op, 0, ecx.machine.layouts.i32)
 }
 
 fn condattr_set_clock_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     attr_op: &OpTy<'tcx, Provenance>,
     clock_id: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -212,14 +212,14 @@ fn condattr_set_clock_id<'mir, 'tcx: 'mir>(
 // bytes 8-11: the clock id constant as i32
 
 fn cond_get_id<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset_atomic(cond_op, 4, ecx.machine.layouts.u32, AtomicReadOrd::Relaxed)
 }
 
 fn cond_set_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
     id: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -233,7 +233,7 @@ fn cond_set_id<'mir, 'tcx: 'mir>(
 }
 
 fn cond_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, CondvarId> {
     let value_place = ecx.deref_operand_and_offset(cond_op, 4, ecx.machine.layouts.u32)?;
@@ -260,14 +260,14 @@ fn cond_get_or_create_id<'mir, 'tcx: 'mir>(
 }
 
 fn cond_get_clock_id<'mir, 'tcx: 'mir>(
-    ecx: &MiriEvalContext<'mir, 'tcx>,
+    ecx: &MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, Scalar<Provenance>> {
     ecx.read_scalar_at_offset(cond_op, 8, ecx.machine.layouts.i32)
 }
 
 fn cond_set_clock_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
     clock_id: impl Into<Scalar<Provenance>>,
 ) -> InterpResult<'tcx, ()> {
@@ -282,7 +282,7 @@ fn cond_set_clock_id<'mir, 'tcx: 'mir>(
 /// Try to reacquire the mutex associated with the condition variable after we
 /// were signaled.
 fn reacquire_cond_mutex<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     thread: ThreadId,
     mutex: MutexId,
 ) -> InterpResult<'tcx> {
@@ -299,7 +299,7 @@ fn reacquire_cond_mutex<'mir, 'tcx: 'mir>(
 /// Reacquire the conditional variable and remove the timeout callback if any
 /// was registered.
 fn post_cond_signal<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     thread: ThreadId,
     mutex: MutexId,
 ) -> InterpResult<'tcx> {
@@ -313,7 +313,7 @@ fn post_cond_signal<'mir, 'tcx: 'mir>(
 /// Release the mutex associated with the condition variable because we are
 /// entering the waiting state.
 fn release_cond_mutex_and_block<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     active_thread: ThreadId,
     mutex: MutexId,
 ) -> InterpResult<'tcx> {
@@ -328,8 +328,8 @@ fn release_cond_mutex_and_block<'mir, 'tcx: 'mir>(
     Ok(())
 }
 
-impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn pthread_mutexattr_init(
         &mut self,
         attr_op: &OpTy<'tcx, Provenance>,
diff --git a/src/shims/unix/thread.rs b/src/shims/unix/thread.rs
index 9365ec9a21f..59474d8d10a 100644
--- a/src/shims/unix/thread.rs
+++ b/src/shims/unix/thread.rs
@@ -2,8 +2,8 @@ use crate::*;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_target::spec::abi::Abi;
 
-impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn pthread_create(
         &mut self,
         thread: &OpTy<'tcx, Provenance>,
diff --git a/src/shims/windows/dlsym.rs b/src/shims/windows/dlsym.rs
index 8749ed91bb4..41b9473f81f 100644
--- a/src/shims/windows/dlsym.rs
+++ b/src/shims/windows/dlsym.rs
@@ -27,8 +27,8 @@ impl Dlsym {
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn call_dlsym(
         &mut self,
         dlsym: Dlsym,
diff --git a/src/shims/windows/foreign_items.rs b/src/shims/windows/foreign_items.rs
index 88129ed8857..53ab97b255e 100644
--- a/src/shims/windows/foreign_items.rs
+++ b/src/shims/windows/foreign_items.rs
@@ -12,8 +12,8 @@ use shims::windows::thread::EvalContextExt as _;
 
 use smallvec::SmallVec;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn emulate_foreign_item_by_name(
         &mut self,
         link_name: Symbol,
diff --git a/src/shims/windows/handle.rs b/src/shims/windows/handle.rs
index 69a6bd38d09..5b22c4bd735 100644
--- a/src/shims/windows/handle.rs
+++ b/src/shims/windows/handle.rs
@@ -145,10 +145,10 @@ impl Handle {
     }
 }
 
-impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
 #[allow(non_snake_case)]
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn invalid_handle(&mut self, function_name: &str) -> InterpResult<'tcx, !> {
         throw_machine_stop!(TerminationInfo::Abort(format!(
             "invalid handle passed to `{function_name}`"
diff --git a/src/shims/windows/sync.rs b/src/shims/windows/sync.rs
index 60645ee7d95..dc1052a824d 100644
--- a/src/shims/windows/sync.rs
+++ b/src/shims/windows/sync.rs
@@ -4,7 +4,7 @@ use crate::*;
 // We use the first 4 bytes to store the RwLockId.
 
 fn srwlock_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriEvalContext<'mir, 'tcx>,
+    ecx: &mut MiriInterpCx<'mir, 'tcx>,
     lock_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, RwLockId> {
     let value_place = ecx.deref_operand_and_offset(lock_op, 0, ecx.machine.layouts.u32)?;
@@ -30,8 +30,8 @@ fn srwlock_get_or_create_id<'mir, 'tcx: 'mir>(
     })
 }
 
-impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     #[allow(non_snake_case)]
     fn AcquireSRWLockExclusive(&mut self, lock_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
diff --git a/src/shims/windows/thread.rs b/src/shims/windows/thread.rs
index 2b801ae3120..5ed0cb92f9e 100644
--- a/src/shims/windows/thread.rs
+++ b/src/shims/windows/thread.rs
@@ -4,10 +4,10 @@ use rustc_target::spec::abi::Abi;
 use crate::*;
 use shims::windows::handle::{EvalContextExt as _, Handle, PseudoHandle};
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 
 #[allow(non_snake_case)]
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn CreateThread(
         &mut self,
         security_op: &OpTy<'tcx, Provenance>,
diff --git a/src/stacked_borrows/diagnostics.rs b/src/stacked_borrows/diagnostics.rs
index 461715cedd8..0d76ed4e308 100644
--- a/src/stacked_borrows/diagnostics.rs
+++ b/src/stacked_borrows/diagnostics.rs
@@ -471,7 +471,9 @@ impl<'span, 'history, 'ecx, 'mir, 'tcx> DiagnosticCx<'span, 'history, 'ecx, 'mir
                 Some((orig_tag, kind))
             }
         };
-        register_diagnostic(NonHaltingDiagnostic::PoppedPointerTag(*item, summary));
+        self.current_span
+            .machine()
+            .emit_diagnostic(NonHaltingDiagnostic::PoppedPointerTag(*item, summary));
     }
 }
 
diff --git a/src/stacked_borrows/mod.rs b/src/stacked_borrows/mod.rs
index 92576284566..f7f4b1357f1 100644
--- a/src/stacked_borrows/mod.rs
+++ b/src/stacked_borrows/mod.rs
@@ -178,11 +178,11 @@ impl GlobalStateInner {
         id
     }
 
-    pub fn new_frame(&mut self) -> FrameExtra {
+    pub fn new_frame(&mut self, machine: &MiriMachine<'_, '_>) -> FrameExtra {
         let call_id = self.next_call_id;
         trace!("new_frame: Assigning call ID {}", call_id);
         if self.tracked_call_ids.contains(&call_id) {
-            register_diagnostic(NonHaltingDiagnostic::CreatedCallId(call_id));
+            machine.emit_diagnostic(NonHaltingDiagnostic::CreatedCallId(call_id));
         }
         self.next_call_id = NonZeroU64::new(call_id.get() + 1).unwrap();
         FrameExtra { call_id, protected_tags: SmallVec::new() }
@@ -199,11 +199,11 @@ impl GlobalStateInner {
         }
     }
 
-    pub fn base_ptr_tag(&mut self, id: AllocId) -> SbTag {
+    pub fn base_ptr_tag(&mut self, id: AllocId, machine: &MiriMachine<'_, '_>) -> SbTag {
         self.base_ptr_tags.get(&id).copied().unwrap_or_else(|| {
             let tag = self.new_ptr();
             if self.tracked_pointer_tags.contains(&tag) {
-                register_diagnostic(NonHaltingDiagnostic::CreatedPointerTag(tag.0, None));
+                machine.emit_diagnostic(NonHaltingDiagnostic::CreatedPointerTag(tag.0, None));
             }
             trace!("New allocation {:?} has base tag {:?}", id, tag);
             self.base_ptr_tags.try_insert(id, tag).unwrap();
@@ -572,9 +572,10 @@ impl Stacks {
             // not through a pointer). That is, whenever we directly write to a local, this will pop
             // everything else off the stack, invalidating all previous pointers,
             // and in particular, *all* raw pointers.
-            MemoryKind::Stack => (extra.base_ptr_tag(id), Permission::Unique),
+            MemoryKind::Stack =>
+                (extra.base_ptr_tag(id, current_span.machine()), Permission::Unique),
             // Everything else is shared by default.
-            _ => (extra.base_ptr_tag(id), Permission::SharedReadWrite),
+            _ => (extra.base_ptr_tag(id, current_span.machine()), Permission::SharedReadWrite),
         };
         Stacks::new(size, perm, base_tag, id, &mut current_span)
     }
@@ -651,10 +652,10 @@ impl Stacks {
 /// Retagging/reborrowing.  There is some policy in here, such as which permissions
 /// to grant for which references, and when to add protectors.
 impl<'mir: 'ecx, 'tcx: 'mir, 'ecx> EvalContextPrivExt<'mir, 'tcx, 'ecx>
-    for crate::MiriEvalContext<'mir, 'tcx>
+    for crate::MiriInterpCx<'mir, 'tcx>
 {
 }
-trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextExt<'mir, 'tcx> {
+trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Returns the `AllocId` the reborrow was done in, if some actual borrow stack manipulation
     /// happened.
     fn reborrow(
@@ -669,12 +670,12 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
         let this = self.eval_context_mut();
 
         // It is crucial that this gets called on all code paths, to ensure we track tag creation.
-        let log_creation = |this: &MiriEvalContext<'mir, 'tcx>,
+        let log_creation = |this: &MiriInterpCx<'mir, 'tcx>,
                             loc: Option<(AllocId, Size, ProvenanceExtra)>| // alloc_id, base_offset, orig_tag
          -> InterpResult<'tcx> {
             let global = this.machine.stacked_borrows.as_ref().unwrap().borrow();
             if global.tracked_pointer_tags.contains(&new_tag) {
-                register_diagnostic(NonHaltingDiagnostic::CreatedPointerTag(
+                this.emit_diagnostic(NonHaltingDiagnostic::CreatedPointerTag(
                     new_tag.0,
                     loc.map(|(alloc_id, base_offset, _)| (alloc_id, alloc_range(base_offset, size))),
                 ));
@@ -688,7 +689,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
             let (_size, _align, alloc_kind) = this.get_alloc_info(alloc_id);
             match alloc_kind {
                 AllocKind::LiveData => {
-                    let current_span = &mut this.machine.current_span(*this.tcx);
+                    let current_span = &mut this.machine.current_span();
                     // This should have alloc_extra data, but `get_alloc_extra` can still fail
                     // if converting this alloc_id from a global to a local one
                     // uncovers a non-supported `extern static`.
@@ -805,7 +806,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
                     .expect("we should have Stacked Borrows data")
                     .borrow_mut();
                 // FIXME: can't share this with the current_span inside log_creation
-                let mut current_span = this.machine.current_span(*this.tcx);
+                let mut current_span = this.machine.current_span();
                 this.visit_freeze_sensitive(place, size, |mut range, frozen| {
                     // Adjust range.
                     range.start += base_offset;
@@ -843,7 +844,6 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
         // Here we can avoid `borrow()` calls because we have mutable references.
         // Note that this asserts that the allocation is mutable -- but since we are creating a
         // mutable pointer, that seems reasonable.
-        let tcx = *this.tcx;
         let (alloc_extra, machine) = this.get_alloc_extra_mut(alloc_id)?;
         let mut stacked_borrows = alloc_extra
             .stacked_borrows
@@ -854,7 +854,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
         let range = alloc_range(base_offset, size);
         let mut global = machine.stacked_borrows.as_ref().unwrap().borrow_mut();
         // FIXME: can't share this with the current_span inside log_creation
-        let current_span = &mut machine.current_span(tcx);
+        let current_span = &mut machine.current_span();
         let dcx = DiagnosticCxBuilder::retag(
             current_span,
             &machine.threads,
@@ -920,8 +920,8 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriEvalContextEx
     }
 }
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn retag(&mut self, kind: RetagKind, place: &PlaceTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
         let retag_fields = this.machine.stacked_borrows.as_mut().unwrap().get_mut().retag_fields;
@@ -957,7 +957,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
 
         // The actual visitor.
         struct RetagVisitor<'ecx, 'mir, 'tcx> {
-            ecx: &'ecx mut MiriEvalContext<'mir, 'tcx>,
+            ecx: &'ecx mut MiriInterpCx<'mir, 'tcx>,
             kind: RetagKind,
             retag_cause: RetagCause,
             retag_fields: bool,
@@ -977,13 +977,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 Ok(())
             }
         }
-        impl<'ecx, 'mir, 'tcx> MutValueVisitor<'mir, 'tcx, Evaluator<'mir, 'tcx>>
+        impl<'ecx, 'mir, 'tcx> MutValueVisitor<'mir, 'tcx, MiriMachine<'mir, 'tcx>>
             for RetagVisitor<'ecx, 'mir, 'tcx>
         {
             type V = PlaceTy<'tcx, Provenance>;
 
             #[inline(always)]
-            fn ecx(&mut self) -> &mut MiriEvalContext<'mir, 'tcx> {
+            fn ecx(&mut self) -> &mut MiriInterpCx<'mir, 'tcx> {
                 self.ecx
             }
 
diff --git a/src/tag_gc.rs b/src/tag_gc.rs
index 0402e4d35dd..e20a8671147 100644
--- a/src/tag_gc.rs
+++ b/src/tag_gc.rs
@@ -1,8 +1,8 @@
 use crate::*;
 use rustc_data_structures::fx::FxHashSet;
 
-impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
-pub trait EvalContextExt<'mir, 'tcx: 'mir>: MiriEvalContextExt<'mir, 'tcx> {
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: MiriInterpCxExt<'mir, 'tcx> {
     fn garbage_collect_tags(&mut self) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
         // No reason to do anything at all if stacked borrows is off.