From 395f5d40dcd50b3e83c3cd0a15f1927c141bf48c Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 27 Jun 2020 12:36:20 +0200
Subject: [PATCH 1/2] Rename shims::{sync -> posic_sync} and move
 sync_singlethread test to other sync test

---
 src/lib.rs                                    | 24 +++++++++----------
 src/shims/{sync.rs => posix_sync.rs}          |  3 +++
 src/thread.rs                                 |  4 ++--
 .../{ => concurrency}/sync_singlethread.rs    |  0
 4 files changed, 17 insertions(+), 14 deletions(-)
 rename src/shims/{sync.rs => posix_sync.rs} (99%)
 rename tests/run-pass/{ => concurrency}/sync_singlethread.rs (100%)

diff --git a/src/lib.rs b/src/lib.rs
index e79fc2add39e..e0da83840edd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -39,18 +39,18 @@ pub use rustc_mir::interpret::*;
 // Resolve ambiguity.
 pub use rustc_mir::interpret::{self, AllocMap, PlaceTy};
 
-pub use crate::shims::dlsym::{Dlsym, EvalContextExt as DlsymEvalContextExt};
-pub use crate::shims::env::{EnvVars, EvalContextExt as EnvEvalContextExt};
-pub use crate::shims::foreign_items::EvalContextExt as ForeignItemsEvalContextExt;
-pub use crate::shims::fs::{DirHandler, EvalContextExt as FileEvalContextExt, FileHandler};
-pub use crate::shims::intrinsics::EvalContextExt as IntrinsicsEvalContextExt;
-pub use crate::shims::os_str::EvalContextExt as OsStrEvalContextExt;
-pub use crate::shims::panic::{CatchUnwindData, EvalContextExt as PanicEvalContextExt};
-pub use crate::shims::sync::{EvalContextExt as SyncShimsEvalContextExt};
-pub use crate::shims::thread::EvalContextExt as ThreadShimsEvalContextExt;
-pub use crate::shims::time::EvalContextExt as TimeEvalContextExt;
-pub use crate::shims::tls::{EvalContextExt as TlsEvalContextExt, TlsData};
-pub use crate::shims::EvalContextExt as ShimsEvalContextExt;
+pub use crate::shims::dlsym::{Dlsym, EvalContextExt as _};
+pub use crate::shims::env::{EnvVars, EvalContextExt as _};
+pub use crate::shims::foreign_items::EvalContextExt as _;
+pub use crate::shims::fs::{DirHandler, EvalContextExt as _, FileHandler};
+pub use crate::shims::intrinsics::EvalContextExt as _;
+pub use crate::shims::os_str::EvalContextExt as _;
+pub use crate::shims::panic::{CatchUnwindData, EvalContextExt as _};
+pub use crate::shims::posix_sync::{EvalContextExt as _};
+pub use crate::shims::thread::EvalContextExt as _;
+pub use crate::shims::time::EvalContextExt as _;
+pub use crate::shims::tls::{EvalContextExt as _, TlsData};
+pub use crate::shims::EvalContextExt as _;
 
 pub use crate::diagnostics::{
     register_diagnostic, report_error, EvalContextExt as DiagnosticsEvalContextExt,
diff --git a/src/shims/sync.rs b/src/shims/posix_sync.rs
similarity index 99%
rename from src/shims/sync.rs
rename to src/shims/posix_sync.rs
index 8986455a14fc..cdc1f8cc763a 100644
--- a/src/shims/sync.rs
+++ b/src/shims/posix_sync.rs
@@ -522,6 +522,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
 
         mutex_set_kind(this, mutex_op, ScalarMaybeUninit::Uninit)?;
         mutex_set_id(this, mutex_op, ScalarMaybeUninit::Uninit)?;
+        // FIXME: delete interpreter state associated with this mutex.
 
         Ok(0)
     }
@@ -640,6 +641,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         }
 
         rwlock_set_id(this, rwlock_op, ScalarMaybeUninit::Uninit)?;
+        // FIXME: delete interpreter state associated with this rwlock.
 
         Ok(0)
     }
@@ -833,6 +835,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         }
         cond_set_id(this, cond_op, ScalarMaybeUninit::Uninit)?;
         cond_set_clock_id(this, cond_op, ScalarMaybeUninit::Uninit)?;
+        // FIXME: delete interpreter state associated with this condvar.
 
         Ok(0)
     }
diff --git a/src/thread.rs b/src/thread.rs
index 246a383d178b..896f93ef1a3a 100644
--- a/src/thread.rs
+++ b/src/thread.rs
@@ -91,8 +91,8 @@ pub enum ThreadState {
     /// responsibility of the synchronization primitives to track threads that
     /// are blocked by them.
     BlockedOnSync,
-    /// The thread has terminated its execution (we do not delete terminated
-    /// threads).
+    /// The thread has terminated its execution. We do not delete terminated
+    /// threads (FIXME: why?).
     Terminated,
 }
 
diff --git a/tests/run-pass/sync_singlethread.rs b/tests/run-pass/concurrency/sync_singlethread.rs
similarity index 100%
rename from tests/run-pass/sync_singlethread.rs
rename to tests/run-pass/concurrency/sync_singlethread.rs

From af5887e869c91df9920856e2ba2ee3e85cea6a78 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 27 Jun 2020 13:19:35 +0200
Subject: [PATCH 2/2] module organization: move platform-specific code to
 shims::{posix::{linux, macos}, windows}

---
 src/intptrcast.rs                                 |  2 +-
 src/lib.rs                                        |  7 +++----
 src/machine.rs                                    |  4 ++--
 src/shims/foreign_items.rs                        |  9 +++------
 src/shims/mod.rs                                  | 13 ++++++++-----
 .../posix.rs => posix/foreign_items.rs}           | 15 ++++++++-------
 src/shims/{ => posix}/fs.rs                       |  4 ++--
 .../linux.rs => posix/linux/foreign_items.rs}     |  8 ++++++--
 src/shims/posix/linux/mod.rs                      |  1 +
 .../macos.rs => posix/macos/foreign_items.rs}     |  5 ++++-
 src/shims/posix/macos/mod.rs                      |  1 +
 src/shims/posix/mod.rs                            | 10 ++++++++++
 src/shims/{posix_sync.rs => posix/sync.rs}        |  6 +++---
 src/shims/{ => posix}/thread.rs                   |  0
 src/shims/tls.rs                                  |  5 +----
 .../windows.rs => windows/foreign_items.rs}       |  0
 src/shims/windows/mod.rs                          |  1 +
 17 files changed, 54 insertions(+), 37 deletions(-)
 rename src/shims/{foreign_items/posix.rs => posix/foreign_items.rs} (98%)
 rename src/shims/{ => posix}/fs.rs (99%)
 rename src/shims/{foreign_items/posix/linux.rs => posix/linux/foreign_items.rs} (97%)
 create mode 100644 src/shims/posix/linux/mod.rs
 rename src/shims/{foreign_items/posix/macos.rs => posix/macos/foreign_items.rs} (98%)
 create mode 100644 src/shims/posix/macos/mod.rs
 create mode 100644 src/shims/posix/mod.rs
 rename src/shims/{posix_sync.rs => posix/sync.rs} (99%)
 rename src/shims/{ => posix}/thread.rs (100%)
 rename src/shims/{foreign_items/windows.rs => windows/foreign_items.rs} (100%)
 create mode 100644 src/shims/windows/mod.rs

diff --git a/src/intptrcast.rs b/src/intptrcast.rs
index f51c8a7ce743..c908bdf24eba 100644
--- a/src/intptrcast.rs
+++ b/src/intptrcast.rs
@@ -9,7 +9,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_mir::interpret::{AllocCheck, AllocId, InterpResult, Memory, Machine, Pointer, PointerArithmetic};
 use rustc_target::abi::{Size, HasDataLayout};
 
-use crate::{Evaluator, Tag, STACK_ADDR, CheckInAllocMsg};
+use crate::*;
 
 pub type MemoryExtra = RefCell<GlobalState>;
 
diff --git a/src/lib.rs b/src/lib.rs
index e0da83840edd..fa357eb9b134 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -34,6 +34,8 @@ mod stacked_borrows;
 mod sync;
 mod thread;
 
+// Establish a "crate-wide prelude": we often import `crate::*`.
+
 // Make all those symbols available in the same place as our own.
 pub use rustc_mir::interpret::*;
 // Resolve ambiguity.
@@ -42,13 +44,10 @@ pub use rustc_mir::interpret::{self, AllocMap, PlaceTy};
 pub use crate::shims::dlsym::{Dlsym, EvalContextExt as _};
 pub use crate::shims::env::{EnvVars, EvalContextExt as _};
 pub use crate::shims::foreign_items::EvalContextExt as _;
-pub use crate::shims::fs::{DirHandler, EvalContextExt as _, FileHandler};
 pub use crate::shims::intrinsics::EvalContextExt as _;
 pub use crate::shims::os_str::EvalContextExt as _;
-pub use crate::shims::panic::{CatchUnwindData, EvalContextExt as _};
-pub use crate::shims::posix_sync::{EvalContextExt as _};
-pub use crate::shims::thread::EvalContextExt as _;
 pub use crate::shims::time::EvalContextExt as _;
+pub use crate::shims::panic::{CatchUnwindData, EvalContextExt as _};
 pub use crate::shims::tls::{EvalContextExt as _, TlsData};
 pub use crate::shims::EvalContextExt as _;
 
diff --git a/src/machine.rs b/src/machine.rs
index 4f45b4f93f18..6233222c004d 100644
--- a/src/machine.rs
+++ b/src/machine.rs
@@ -241,8 +241,8 @@ pub struct Evaluator<'mir, 'tcx> {
     /// Whether to enforce the validity invariant.
     pub(crate) validate: bool,
 
-    pub(crate) file_handler: FileHandler,
-    pub(crate) dir_handler: DirHandler,
+    pub(crate) file_handler: shims::posix::FileHandler,
+    pub(crate) dir_handler: shims::posix::DirHandler,
 
     /// The temporary used for storing the argument of
     /// the call to `miri_start_panic` (the panic payload) when unwinding.
diff --git a/src/shims/foreign_items.rs b/src/shims/foreign_items.rs
index 8a75fb03a53c..14c5aac4899a 100644
--- a/src/shims/foreign_items.rs
+++ b/src/shims/foreign_items.rs
@@ -1,6 +1,3 @@
-mod windows;
-mod posix;
-
 use std::{convert::{TryInto, TryFrom}, iter};
 
 use rustc_hir::def_id::DefId;
@@ -455,13 +452,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
             // Architecture-specific shims
             "llvm.x86.sse2.pause" if this.tcx.sess.target.target.arch == "x86" || this.tcx.sess.target.target.arch == "x86_64" => {
                 let &[] = check_arg_count(args)?;
-                this.sched_yield()?;
+                this.yield_active_thread();
             }
 
             // Platform-specific shims
             _ => match this.tcx.sess.target.target.target_os.as_str() {
-                "linux" | "macos" => return posix::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
-                "windows" => return windows::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
+                "linux" | "macos" => return shims::posix::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
+                "windows" => return shims::windows::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
                 target => throw_unsup_format!("the target `{}` is not supported", target),
             }
         };
diff --git a/src/shims/mod.rs b/src/shims/mod.rs
index cd525e173ed7..37e7b8c40462 100644
--- a/src/shims/mod.rs
+++ b/src/shims/mod.rs
@@ -1,15 +1,18 @@
+
+pub mod foreign_items;
+pub mod intrinsics;
+pub mod posix;
+pub mod windows;
+
 pub mod dlsym;
 pub mod env;
-pub mod foreign_items;
-pub mod fs;
-pub mod intrinsics;
 pub mod os_str;
 pub mod panic;
-pub mod sync;
-pub mod thread;
 pub mod time;
 pub mod tls;
 
+// End module management, begin local code
+
 use std::convert::TryFrom;
 
 use log::trace;
diff --git a/src/shims/foreign_items/posix.rs b/src/shims/posix/foreign_items.rs
similarity index 98%
rename from src/shims/foreign_items/posix.rs
rename to src/shims/posix/foreign_items.rs
index 8e4d140b06cb..bbda40def620 100644
--- a/src/shims/foreign_items/posix.rs
+++ b/src/shims/posix/foreign_items.rs
@@ -1,15 +1,16 @@
-mod linux;
-mod macos;
-
 use std::convert::TryFrom;
 
 use log::trace;
 
-use crate::*;
-use helpers::check_arg_count;
 use rustc_middle::mir;
 use rustc_target::abi::{Align, LayoutOf, Size};
 
+use crate::*;
+use helpers::check_arg_count;
+use shims::posix::fs::EvalContextExt as _;
+use shims::posix::sync::EvalContextExt as _;
+use shims::posix::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> {
     fn emulate_foreign_item_by_name(
@@ -476,8 +477,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
             // Platform-specific shims
             _ => {
                 match this.tcx.sess.target.target.target_os.as_str() {
-                    "linux" => return linux::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
-                    "macos" => return macos::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
+                    "linux" => return shims::posix::linux::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
+                    "macos" => return shims::posix::macos::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest, ret),
                     _ => unreachable!(),
                 }
             }
diff --git a/src/shims/fs.rs b/src/shims/posix/fs.rs
similarity index 99%
rename from src/shims/fs.rs
rename to src/shims/posix/fs.rs
index 29e0da14ff1e..87aa28120c28 100644
--- a/src/shims/fs.rs
+++ b/src/shims/posix/fs.rs
@@ -10,13 +10,13 @@ use log::trace;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_target::abi::{Align, LayoutOf, Size};
 
-use crate::stacked_borrows::Tag;
 use crate::*;
+use stacked_borrows::Tag;
 use helpers::{check_arg_count, immty_from_int_checked, immty_from_uint_checked};
 use shims::time::system_time_to_duration;
 
 #[derive(Debug)]
-pub struct FileHandle {
+struct FileHandle {
     file: File,
     writable: bool,
 }
diff --git a/src/shims/foreign_items/posix/linux.rs b/src/shims/posix/linux/foreign_items.rs
similarity index 97%
rename from src/shims/foreign_items/posix/linux.rs
rename to src/shims/posix/linux/foreign_items.rs
index 2d124f9d8c6c..ff30609d9ab2 100644
--- a/src/shims/foreign_items/posix/linux.rs
+++ b/src/shims/posix/linux/foreign_items.rs
@@ -1,7 +1,11 @@
-use crate::*;
-use helpers::check_arg_count;
 use rustc_middle::mir;
 
+use crate::*;
+use crate::helpers::check_arg_count;
+use shims::posix::fs::EvalContextExt as _;
+use shims::posix::sync::EvalContextExt as _;
+use shims::posix::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> {
     fn emulate_foreign_item_by_name(
diff --git a/src/shims/posix/linux/mod.rs b/src/shims/posix/linux/mod.rs
new file mode 100644
index 000000000000..09c6507b24f8
--- /dev/null
+++ b/src/shims/posix/linux/mod.rs
@@ -0,0 +1 @@
+pub mod foreign_items;
diff --git a/src/shims/foreign_items/posix/macos.rs b/src/shims/posix/macos/foreign_items.rs
similarity index 98%
rename from src/shims/foreign_items/posix/macos.rs
rename to src/shims/posix/macos/foreign_items.rs
index fb50e4d91817..ef649c3e8406 100644
--- a/src/shims/foreign_items/posix/macos.rs
+++ b/src/shims/posix/macos/foreign_items.rs
@@ -1,6 +1,9 @@
+use rustc_middle::mir;
+
 use crate::*;
 use helpers::check_arg_count;
-use rustc_middle::mir;
+use shims::posix::fs::EvalContextExt as _;
+use shims::posix::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> {
diff --git a/src/shims/posix/macos/mod.rs b/src/shims/posix/macos/mod.rs
new file mode 100644
index 000000000000..09c6507b24f8
--- /dev/null
+++ b/src/shims/posix/macos/mod.rs
@@ -0,0 +1 @@
+pub mod foreign_items;
diff --git a/src/shims/posix/mod.rs b/src/shims/posix/mod.rs
new file mode 100644
index 000000000000..2f505cfb9c0b
--- /dev/null
+++ b/src/shims/posix/mod.rs
@@ -0,0 +1,10 @@
+pub mod foreign_items;
+
+mod fs;
+mod sync;
+mod thread;
+
+mod linux;
+mod macos;
+
+pub use fs::{DirHandler, FileHandler};
diff --git a/src/shims/posix_sync.rs b/src/shims/posix/sync.rs
similarity index 99%
rename from src/shims/posix_sync.rs
rename to src/shims/posix/sync.rs
index cdc1f8cc763a..a61c80d5118c 100644
--- a/src/shims/posix_sync.rs
+++ b/src/shims/posix/sync.rs
@@ -5,10 +5,10 @@ use std::ops::Not;
 use rustc_middle::ty::{layout::TyAndLayout, TyKind, TypeAndMut};
 use rustc_target::abi::{LayoutOf, Size};
 
-use crate::stacked_borrows::Tag;
-use crate::thread::Time;
-
 use crate::*;
+use stacked_borrows::Tag;
+use thread::Time;
+
 
 fn assert_ptr_target_min_size<'mir, 'tcx: 'mir>(
     ecx: &MiriEvalContext<'mir, 'tcx>,
diff --git a/src/shims/thread.rs b/src/shims/posix/thread.rs
similarity index 100%
rename from src/shims/thread.rs
rename to src/shims/posix/thread.rs
diff --git a/src/shims/tls.rs b/src/shims/tls.rs
index 695614633682..704598ef2c6c 100644
--- a/src/shims/tls.rs
+++ b/src/shims/tls.rs
@@ -10,10 +10,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::ty;
 use rustc_target::abi::{Size, HasDataLayout};
 
-use crate::{
-    HelpersEvalContextExt, InterpResult, MPlaceTy, Scalar, StackPopCleanup, Tag, ThreadId,
-    ThreadsEvalContextExt,
-};
+use crate::*;
 
 pub type TlsKey = u128;
 
diff --git a/src/shims/foreign_items/windows.rs b/src/shims/windows/foreign_items.rs
similarity index 100%
rename from src/shims/foreign_items/windows.rs
rename to src/shims/windows/foreign_items.rs
diff --git a/src/shims/windows/mod.rs b/src/shims/windows/mod.rs
new file mode 100644
index 000000000000..09c6507b24f8
--- /dev/null
+++ b/src/shims/windows/mod.rs
@@ -0,0 +1 @@
+pub mod foreign_items;