Auto merge of #2426 - saethlin:unix-exec, r=RalfJung

[rust.git] / src / eval.rs

diff --git a/src/eval.rs b/src/eval.rs
index 1536b826ac46647ad4e2b1bd6c40d2713c310fff..53264bd465914e943ba5bf4b405dcf73085d5117 100644 (file)
--- a/src/eval.rs
+++ b/src/eval.rs
@@ -1,7 +1,10 @@
 //! Main evaluator loop and setting up the initial stack frame.
 
+use std::collections::HashSet;
 use std::ffi::OsStr;
 use std::iter;
+use std::panic::{self, AssertUnwindSafe};
+use std::thread;
 
 use log::info;
 
@@ -15,8 +18,6 @@
 
 use rustc_session::config::EntryFnType;
 
-use std::collections::HashSet;
-
 use crate::*;
 
 #[derive(Copy, Clone, Debug, PartialEq)]
@@ -77,10 +78,6 @@ pub struct MiriConfig {
     pub stacked_borrows: bool,
     /// Controls alignment checking.
     pub check_alignment: AlignmentCheck,
-    /// Controls integer and float validity initialization checking.
-    pub allow_uninit_numbers: bool,
-    /// Controls how we treat ptr2int and int2ptr transmutes.
-    pub allow_ptr_int_transmute: bool,
     /// Controls function [ABI](Abi) checking.
     pub check_abi: bool,
     /// Action for an op requiring communication with the host.
@@ -105,6 +102,8 @@ pub struct MiriConfig {
     pub data_race_detector: bool,
     /// Determine if weak memory emulation should be enabled. Requires data race detection to be enabled
     pub weak_memory_emulation: bool,
+    /// Track when an outdated (weak memory) load happens.
+    pub track_outdated_loads: bool,
     /// Rate of spurious failures for compare_exchange_weak atomic operations,
     /// between 0.0 and 1.0, defaulting to 0.8 (80% chance of failure).
     pub cmpxchg_weak_failure_rate: f64,
@@ -134,8 +133,6 @@ fn default() -> MiriConfig {
             validate: true,
             stacked_borrows: true,
             check_alignment: AlignmentCheck::Int,
-            allow_uninit_numbers: false,
-            allow_ptr_int_transmute: false,
             check_abi: true,
             isolated_op: IsolatedOp::Reject(RejectOpWith::Abort),
             ignore_leaks: false,
@@ -148,6 +145,7 @@ fn default() -> MiriConfig {
             tracked_alloc_ids: HashSet::default(),
             data_race_detector: true,
             weak_memory_emulation: true,
+            track_outdated_loads: false,
             cmpxchg_weak_failure_rate: 0.8, // 80%
             measureme_out: None,
             panic_on_unsupported: false,
@@ -170,7 +168,7 @@ 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, Tag>)> {
+) -> InterpResult<'tcx, (InterpCx<'mir, 'tcx, Evaluator<'mir, 'tcx>>, MPlaceTy<'tcx, Provenance>)> {
     let param_env = ty::ParamEnv::reveal_all();
     let layout_cx = LayoutCx { tcx, param_env };
     let mut ecx = InterpCx::new(
@@ -207,7 +205,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
     // Third argument (`argv`): created from `config.args`.
     let argv = {
         // Put each argument in memory, collect pointers.
-        let mut argvs = Vec::<Immediate<Tag>>::new();
+        let mut argvs = Vec::<Immediate<Provenance>>::new();
         for arg in config.args.iter() {
             // Make space for `0` terminator.
             let size = u64::try_from(arg.len()).unwrap().checked_add(1).unwrap();
@@ -289,7 +287,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
                 start_instance,
                 Abi::Rust,
                 &[Scalar::from_pointer(main_ptr, &ecx).into(), argc.into(), argv],
-                &ret_place.into(),
+                Some(&ret_place.into()),
                 StackPopCleanup::Root { cleanup: true },
             )?;
         }
@@ -298,7 +296,7 @@ pub fn create_ecx<'mir, 'tcx: 'mir>(
                 entry_instance,
                 Abi::Rust,
                 &[argc.into(), argv],
-                &ret_place.into(),
+                Some(&ret_place.into()),
                 StackPopCleanup::Root { cleanup: true },
             )?;
         }
@@ -332,7 +330,7 @@ pub fn eval_entry<'tcx>(
     };
 
     // Perform the main execution.
-    let res: InterpResult<'_, i64> = (|| {
+    let res: thread::Result<InterpResult<'_, i64>> = panic::catch_unwind(AssertUnwindSafe(|| {
         // Main loop.
         loop {
             let info = ecx.preprocess_diagnostics();
@@ -362,15 +360,18 @@ pub fn eval_entry<'tcx>(
         }
         let return_code = ecx.read_scalar(&ret_place.into())?.to_machine_isize(&ecx)?;
         Ok(return_code)
-    })();
-
-    // Machine cleanup.
-    // Execution of the program has halted so any memory access we do here
-    // cannot produce a real data race. If we do not do something to disable
-    // data race detection here, some uncommon combination of errors will
-    // cause a data race to be detected:
-    // https://github.com/rust-lang/miri/issues/2020
-    ecx.allow_data_races_mut(|ecx| EnvVars::cleanup(ecx).unwrap());
+    }));
+    let res = res.unwrap_or_else(|panic_payload| {
+        ecx.handle_ice();
+        panic::resume_unwind(panic_payload)
+    });
+
+    // Machine cleanup. Only do this if all threads have terminated; threads that are still running
+    // might cause data races (https://github.com/rust-lang/miri/issues/2020) or Stacked Borrows
+    // errors (https://github.com/rust-lang/miri/issues/2396) if we deallocate here.
+    if ecx.have_all_terminated() {
+        EnvVars::cleanup(&mut ecx).unwrap();
+    }
 
     // Process the result.
     match res {