update Miri

src/tools/miri/CONTRIBUTING.md

@@ -296,6 +296,13 @@ needed.
 
 ### Exporting changes to the rustc repo
 
+Keep in mind that pushing is the most complicated job that josh has to do --
+pulling just filters the rustc history, but pushing needs to construct a new
+rustc history that would filter to the given Miri history! To avoid problems, it
+is a good idea to always pull immediately before you push. In particular, you
+should never do two josh pushes without an intermediate pull; that can lead to
+duplicated commits.
+
 Josh needs to be running, as described above. We will use the josh proxy to push
 to your fork of rustc. Run the following in the Miri repo, assuming we are on an
 up-to-date master branch:

src/tools/miri/cargo-miri/src/phases.rs

@@ -281,9 +281,10 @@ pub fn phase_rustc(mut args: impl Iterator<Item = String>, phase: RustcPhase) {
             eprintln!("[cargo-miri rustc] writing run info to `{}`", filename.display());
         }
         info.store(&filename);
-        // For Windows, do the same thing again with `.exe` appended to the filename.
+        // For Windows and WASM, do the same thing again with `.exe`/`.wasm` appended to the filename.
         // (Need to do this here as cargo moves that "binary" to a different place before running it.)
         info.store(&out_filename("", ".exe"));
+        info.store(&out_filename("", ".wasm"));
     };
 
     let runnable_crate = !info_query && is_runnable_crate();

src/tools/miri/ci.sh

@@ -1,6 +1,17 @@
 #!/bin/bash
 set -euo pipefail
-set -x
+
+function begingroup {
+  echo "::group::$@"
+  set -x
+}
+
+function endgroup {
+  set +x
+  echo "::endgroup"
+}
+
+begingroup "Building Miri"
 
 # Determine configuration for installed build
 echo "Installing release version of Miri"
@@ -14,14 +25,15 @@ export CARGO_EXTRA_FLAGS="--locked"
 ./miri check --no-default-features # make sure this can be built
 ./miri check --all-features # and this, too
 ./miri build --all-targets # the build that all the `./miri test` below will use
-echo
+
+endgroup
 
 # Test
 function run_tests {
   if [ -n "${MIRI_TEST_TARGET+exists}" ]; then
-    echo "Testing foreign architecture $MIRI_TEST_TARGET"
+    begingroup "Testing foreign architecture $MIRI_TEST_TARGET"
   else
-    echo "Testing host architecture"
+    begingroup "Testing host architecture"
   fi
 
   ## ui test suite
@@ -52,7 +64,6 @@ function run_tests {
   echo 'build.rustc-wrapper = "thisdoesnotexist"' > .cargo/config.toml
   # Run the actual test
   ${PYTHON} test-cargo-miri/run-test.py
-  echo
   # Clean up
   unset RUSTC MIRI
   rm -rf .cargo
@@ -63,16 +74,23 @@ function run_tests {
       cargo miri run --manifest-path bench-cargo-miri/$BENCH/Cargo.toml
     done
   fi
+
+  endgroup
 }
 
 function run_tests_minimal {
   if [ -n "${MIRI_TEST_TARGET+exists}" ]; then
-    echo "Testing MINIMAL foreign architecture $MIRI_TEST_TARGET: only testing $@"
+    begingroup "Testing MINIMAL foreign architecture $MIRI_TEST_TARGET: only testing $@"
   else
-    echo "Testing MINIMAL host architecture: only testing $@"
+    begingroup "Testing MINIMAL host architecture: only testing $@"
   fi
 
   ./miri test -- "$@"
+
+  # Ensure that a small smoke test of cargo-miri works.
+  cargo miri run --manifest-path test-cargo-miri/no-std-smoke/Cargo.toml --target ${MIRI_TEST_TARGET-$HOST_TARGET}
+
+  endgroup
 }
 
 # host
@@ -85,6 +103,7 @@ case $HOST_TARGET in
     MIRI_TEST_TARGET=i686-pc-windows-msvc run_tests
     MIRI_TEST_TARGET=x86_64-unknown-freebsd run_tests_minimal hello integer vec panic/panic concurrency/simple atomic data_race env/var
     MIRI_TEST_TARGET=aarch64-linux-android run_tests_minimal hello integer vec panic/panic
+    MIRI_TEST_TARGET=wasm32-wasi MIRI_NO_STD=1 run_tests_minimal no_std # supports std but miri doesn't support it
     MIRI_TEST_TARGET=thumbv7em-none-eabihf MIRI_NO_STD=1 run_tests_minimal no_std # no_std embedded architecture
     ;;
   x86_64-apple-darwin)

src/tools/miri/rust-version

@@ -1 +1 @@
-7477c1f4f7d6bef037d523099b240d22aa1b63a0
+454784afba5bf35b5ff14ada0e31265ad1d75e73

src/tools/miri/src/concurrency/data_race.rs

@@ -838,18 +838,18 @@ impl VClockAlloc {
         &self,
         alloc_id: AllocId,
         range: AllocRange,
-        global: &GlobalState,
-        thread_mgr: &ThreadManager<'_, '_>,
+        machine: &MiriMachine<'_, '_>,
     ) -> InterpResult<'tcx> {
+        let global = machine.data_race.as_ref().unwrap();
         if global.race_detecting() {
-            let (index, clocks) = global.current_thread_state(thread_mgr);
+            let (index, clocks) = global.current_thread_state(&machine.threads);
             let mut alloc_ranges = self.alloc_ranges.borrow_mut();
             for (offset, range) in alloc_ranges.iter_mut(range.start, range.size) {
                 if let Err(DataRace) = range.read_race_detect(&clocks, index) {
                     // Report data-race.
                     return Self::report_data_race(
                         global,
-                        thread_mgr,
+                        &machine.threads,
                         range,
                         "Read",
                         false,
@@ -869,17 +869,17 @@ impl VClockAlloc {
         alloc_id: AllocId,
         range: AllocRange,
         write_type: WriteType,
-        global: &mut GlobalState,
-        thread_mgr: &ThreadManager<'_, '_>,
+        machine: &mut MiriMachine<'_, '_>,
     ) -> InterpResult<'tcx> {
+        let global = machine.data_race.as_mut().unwrap();
         if global.race_detecting() {
-            let (index, clocks) = global.current_thread_state(thread_mgr);
+            let (index, clocks) = global.current_thread_state(&machine.threads);
             for (offset, range) in self.alloc_ranges.get_mut().iter_mut(range.start, range.size) {
                 if let Err(DataRace) = range.write_race_detect(&clocks, index, write_type) {
                     // Report data-race
                     return Self::report_data_race(
                         global,
-                        thread_mgr,
+                        &machine.threads,
                         range,
                         write_type.get_descriptor(),
                         false,
@@ -901,10 +901,9 @@ impl VClockAlloc {
         &mut self,
         alloc_id: AllocId,
         range: AllocRange,
-        global: &mut GlobalState,
-        thread_mgr: &ThreadManager<'_, '_>,
+        machine: &mut MiriMachine<'_, '_>,
     ) -> InterpResult<'tcx> {
-        self.unique_access(alloc_id, range, WriteType::Write, global, thread_mgr)
+        self.unique_access(alloc_id, range, WriteType::Write, machine)
     }
 
     /// Detect data-races for an unsynchronized deallocate operation, will not perform
@@ -915,10 +914,9 @@ impl VClockAlloc {
         &mut self,
         alloc_id: AllocId,
         range: AllocRange,
-        global: &mut GlobalState,
-        thread_mgr: &ThreadManager<'_, '_>,
+        machine: &mut MiriMachine<'_, '_>,
     ) -> InterpResult<'tcx> {
-        self.unique_access(alloc_id, range, WriteType::Deallocate, global, thread_mgr)
+        self.unique_access(alloc_id, range, WriteType::Deallocate, machine)
     }
 }
 

src/tools/miri/src/concurrency/thread.rs

@@ -118,6 +118,13 @@ pub struct Thread<'mir, 'tcx> {
     /// The virtual call stack.
     stack: Vec<Frame<'mir, 'tcx, Provenance, FrameData<'tcx>>>,
 
+    /// The index of the topmost user-relevant frame in `stack`. This field must contain
+    /// the value produced by `get_top_user_relevant_frame`.
+    /// The `None` state here represents
+    /// This field is a cache to reduce how often we call that method. The cache is manually
+    /// maintained inside `MiriMachine::after_stack_push` and `MiriMachine::after_stack_pop`.
+    top_user_relevant_frame: Option<usize>,
+
     /// The join status.
     join_status: ThreadJoinStatus,
 
@@ -147,6 +154,40 @@ impl<'mir, 'tcx> Thread<'mir, 'tcx> {
     fn thread_name(&self) -> &[u8] {
         if let Some(ref thread_name) = self.thread_name { thread_name } else { b"<unnamed>" }
     }
+
+    /// Return the top user-relevant frame, if there is one.
+    /// Note that the choice to return `None` here when there is no user-relevant frame is part of
+    /// justifying the optimization that only pushes of user-relevant frames require updating the
+    /// `top_user_relevant_frame` field.
+    fn compute_top_user_relevant_frame(&self) -> Option<usize> {
+        self.stack
+            .iter()
+            .enumerate()
+            .rev()
+            .find_map(|(idx, frame)| if frame.extra.is_user_relevant { Some(idx) } else { None })
+    }
+
+    /// Re-compute the top user-relevant frame from scratch.
+    pub fn recompute_top_user_relevant_frame(&mut self) {
+        self.top_user_relevant_frame = self.compute_top_user_relevant_frame();
+    }
+
+    /// Set the top user-relevant frame to the given value. Must be equal to what
+    /// `get_top_user_relevant_frame` would return!
+    pub fn set_top_user_relevant_frame(&mut self, frame_idx: usize) {
+        debug_assert_eq!(Some(frame_idx), self.compute_top_user_relevant_frame());
+        self.top_user_relevant_frame = Some(frame_idx);
+    }
+
+    /// Returns the topmost frame that is considered user-relevant, or the
+    /// top of the stack if there is no such frame, or `None` if the stack is empty.
+    pub fn top_user_relevant_frame(&self) -> Option<usize> {
+        debug_assert_eq!(self.top_user_relevant_frame, self.compute_top_user_relevant_frame());
+        // This can be called upon creation of an allocation. We create allocations while setting up
+        // parts of the Rust runtime when we do not have any stack frames yet, so we need to handle
+        // empty stacks.
+        self.top_user_relevant_frame.or_else(|| self.stack.len().checked_sub(1))
+    }
 }
 
 impl<'mir, 'tcx> std::fmt::Debug for Thread<'mir, 'tcx> {
@@ -167,6 +208,7 @@ impl<'mir, 'tcx> Default for Thread<'mir, 'tcx> {
             state: ThreadState::Enabled,
             thread_name: None,
             stack: Vec::new(),
+            top_user_relevant_frame: None,
             join_status: ThreadJoinStatus::Joinable,
             panic_payload: None,
             last_error: None,
@@ -184,8 +226,15 @@ impl<'mir, 'tcx> Thread<'mir, 'tcx> {
 
 impl VisitTags for Thread<'_, '_> {
     fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
-        let Thread { panic_payload, last_error, stack, state: _, thread_name: _, join_status: _ } =
-            self;
+        let Thread {
+            panic_payload,
+            last_error,
+            stack,
+            top_user_relevant_frame: _,
+            state: _,
+            thread_name: _,
+            join_status: _,
+        } = self;
 
         panic_payload.visit_tags(visit);
         last_error.visit_tags(visit);
@@ -414,7 +463,7 @@ impl<'mir, 'tcx: 'mir> ThreadManager<'mir, 'tcx> {
     }
 
     /// Get a shared borrow of the currently active thread.
-    fn active_thread_ref(&self) -> &Thread<'mir, 'tcx> {
+    pub fn active_thread_ref(&self) -> &Thread<'mir, 'tcx> {
         &self.threads[self.active_thread]
     }
 

src/tools/miri/src/eval.rs

@@ -9,6 +9,7 @@ use std::thread;
 use log::info;
 
 use rustc_data_structures::fx::FxHashSet;
+use rustc_hir::def::Namespace;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::{
     self,
@@ -195,7 +196,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
     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"]);
+    let sentinel = ecx.try_resolve_path(&["core", "ascii", "escape_default"], Namespace::ValueNS);
     if !matches!(sentinel, Some(s) if tcx.is_mir_available(s.def.def_id())) {
         tcx.sess.fatal(
             "the current sysroot was built without `-Zalways-encode-mir`, or libcore seems missing. \