auto merge of #7265 : brson/rust/io-upstream, r=brson

r? @graydon, @nikomatsakis, @pcwalton, or @catamorphism

Sorry this is so huge, but it's been accumulating for about a month. There's lots of stuff here, mostly oriented toward enabling multithreaded scheduling and improving compatibility between the old and new runtimes. Adds task pinning so that we can create the 'platform thread' in servo.

[Here](https://github.com/brson/rust/blob/e1555f9b5628af2b6c6ed344cad621399cb7684d/src/libstd/rt/mod.rs#L201) is the current runtime setup code.

About half of this has already been reviewed.

Author: bors

src/libextra/test.rs

@@ -36,14 +36,6 @@ use std::u64;
 use std::uint;
 use std::vec;
 
-pub mod rustrt {
-    use std::libc::size_t;
-
-    #[abi = "cdecl"]
-    pub extern {
-        pub unsafe fn rust_sched_threads() -> size_t;
-    }
-}
 
 // The name of a test. By convention this follows the rules for rust
 // paths; i.e. it should be a series of identifiers separated by double
@@ -493,11 +485,10 @@ static SCHED_OVERCOMMIT : uint = 1;
 static SCHED_OVERCOMMIT : uint = 4u;
 
 fn get_concurrency() -> uint {
-    unsafe {
-        let threads = rustrt::rust_sched_threads() as uint;
-        if threads == 1 { 1 }
-        else { threads * SCHED_OVERCOMMIT }
-    }
+    use std::rt;
+    let threads = rt::util::default_sched_threads();
+    if threads == 1 { 1 }
+    else { threads * SCHED_OVERCOMMIT }
 }
 
 #[allow(non_implicitly_copyable_typarams)]

src/libstd/at_vec.rs

@@ -22,23 +22,6 @@ use vec::{ImmutableVector, OwnedVector};
 /// Code for dealing with @-vectors. This is pretty incomplete, and
 /// contains a bunch of duplication from the code for ~-vectors.
 
-pub mod rustrt {
-    use libc;
-    use vec;
-    #[cfg(stage0)]
-    use intrinsic::{TyDesc};
-    #[cfg(not(stage0))]
-    use unstable::intrinsics::{TyDesc};
-
-    #[abi = "cdecl"]
-    #[link_name = "rustrt"]
-    pub extern {
-        pub unsafe fn vec_reserve_shared_actual(t: *TyDesc,
-                                                v: **vec::raw::VecRepr,
-                                                n: libc::size_t);
-    }
-}
-
 /// Returns the number of elements the vector can hold without reallocating
 #[inline]
 pub fn capacity<T>(v: @[T]) -> uint {
@@ -192,18 +175,17 @@ pub mod traits {
 pub mod traits {}
 
 pub mod raw {
-    use at_vec::{capacity, rustrt};
+    use at_vec::capacity;
+    use cast;
     use cast::{transmute, transmute_copy};
     use libc;
     use ptr;
     use sys;
     use uint;
-    use unstable::intrinsics::{move_val_init};
+    use unstable::intrinsics;
+    use unstable::intrinsics::{move_val_init, TyDesc};
     use vec;
-    #[cfg(stage0)]
-    use intrinsic::{get_tydesc};
-    #[cfg(not(stage0))]
-    use unstable::intrinsics::{get_tydesc};
+    use vec::UnboxedVecRepr;
 
     pub type VecRepr = vec::raw::VecRepr;
     pub type SliceRepr = vec::raw::SliceRepr;
@@ -264,9 +246,49 @@ pub mod raw {
     pub unsafe fn reserve<T>(v: &mut @[T], n: uint) {
         // Only make the (slow) call into the runtime if we have to
         if capacity(*v) < n {
-            let ptr: **VecRepr = transmute(v);
-            rustrt::vec_reserve_shared_actual(get_tydesc::<T>(),
-                                              ptr, n as libc::size_t);
+            let ptr: *mut *mut VecRepr = transmute(v);
+            let ty = intrinsics::get_tydesc::<T>();
+            // XXX transmute shouldn't be necessary
+            let ty = cast::transmute(ty);
+            return reserve_raw(ty, ptr, n);
+        }
+    }
+
+    // Implementation detail. Shouldn't be public
+    #[allow(missing_doc)]
+    pub fn reserve_raw(ty: *TyDesc, ptr: *mut *mut VecRepr, n: uint) {
+
+        unsafe {
+            let size_in_bytes = n * (*ty).size;
+            if size_in_bytes > (**ptr).unboxed.alloc {
+                let total_size = size_in_bytes + sys::size_of::<UnboxedVecRepr>();
+                // XXX: UnboxedVecRepr has an extra u8 at the end
+                let total_size = total_size - sys::size_of::<u8>();
+                (*ptr) = local_realloc(*ptr as *(), total_size) as *mut VecRepr;
+                (**ptr).unboxed.alloc = size_in_bytes;
+            }
+        }
+
+        fn local_realloc(ptr: *(), size: uint) -> *() {
+            use rt;
+            use rt::OldTaskContext;
+            use rt::local::Local;
+            use rt::task::Task;
+
+            if rt::context() == OldTaskContext {
+                unsafe {
+                    return rust_local_realloc(ptr, size as libc::size_t);
+                }
+
+                extern {
+                    #[fast_ffi]
+                    fn rust_local_realloc(ptr: *(), size: libc::size_t) -> *();
+                }
+            } else {
+                do Local::borrow::<Task, *()> |task| {
+                    task.heap.realloc(ptr as *libc::c_void, size) as *()
+                }
+            }
         }
     }
 

src/libstd/cleanup.rs

@@ -10,105 +10,13 @@
 
 #[doc(hidden)];
 
-use libc::{c_char, intptr_t, uintptr_t};
+use libc::c_void;
 use ptr::{mut_null};
 use repr::BoxRepr;
 use cast::transmute;
 use unstable::intrinsics::TyDesc;
-#[cfg(not(test))] use unstable::lang::clear_task_borrow_list;
 
-/**
- * Runtime structures
- *
- * NB: These must match the representation in the C++ runtime.
- */
-
-type TaskID = uintptr_t;
-
-struct StackSegment { priv opaque: () }
-struct Scheduler { priv opaque: () }
-struct SchedulerLoop { priv opaque: () }
-struct Kernel { priv opaque: () }
-struct Env { priv opaque: () }
-struct AllocHeader { priv opaque: () }
-struct MemoryRegion { priv opaque: () }
-
-#[cfg(target_arch="x86")]
-struct Registers {
-    data: [u32, ..16]
-}
-
-#[cfg(target_arch="arm")]
-#[cfg(target_arch="mips")]
-struct Registers {
-    data: [u32, ..32]
-}
-
-#[cfg(target_arch="x86")]
-#[cfg(target_arch="arm")]
-#[cfg(target_arch="mips")]
-struct Context {
-    regs: Registers,
-    next: *Context,
-    pad: [u32, ..3]
-}
-
-#[cfg(target_arch="x86_64")]
-struct Registers {
-    data: [u64, ..22]
-}
-
-#[cfg(target_arch="x86_64")]
-struct Context {
-    regs: Registers,
-    next: *Context,
-    pad: uintptr_t
-}
-
-struct BoxedRegion {
-    env: *Env,
-    backing_region: *MemoryRegion,
-    live_allocs: *BoxRepr
-}
-
-#[cfg(target_arch="x86")]
-#[cfg(target_arch="arm")]
-#[cfg(target_arch="mips")]
-struct Task {
-    // Public fields
-    refcount: intptr_t,                 // 0
-    id: TaskID,                         // 4
-    pad: [u32, ..2],                    // 8
-    ctx: Context,                       // 16
-    stack_segment: *StackSegment,       // 96
-    runtime_sp: uintptr_t,              // 100
-    scheduler: *Scheduler,              // 104
-    scheduler_loop: *SchedulerLoop,     // 108
-
-    // Fields known only to the runtime
-    kernel: *Kernel,                    // 112
-    name: *c_char,                      // 116
-    list_index: i32,                    // 120
-    boxed_region: BoxedRegion           // 128
-}
-
-#[cfg(target_arch="x86_64")]
-struct Task {
-    // Public fields
-    refcount: intptr_t,
-    id: TaskID,
-    ctx: Context,
-    stack_segment: *StackSegment,
-    runtime_sp: uintptr_t,
-    scheduler: *Scheduler,
-    scheduler_loop: *SchedulerLoop,
-
-    // Fields known only to the runtime
-    kernel: *Kernel,
-    name: *c_char,
-    list_index: i32,
-    boxed_region: BoxedRegion
-}
+type DropGlue<'self> = &'self fn(**TyDesc, *c_void);
 
 /*
  * Box annihilation
@@ -127,9 +35,9 @@ unsafe fn each_live_alloc(read_next_before: bool,
     //! Walks the internal list of allocations
 
     use managed;
+    use rt::local_heap;
 
-    let task: *Task = transmute(rustrt::rust_get_task());
-    let box = (*task).boxed_region.live_allocs;
+    let box = local_heap::live_allocs();
     let mut box: *mut BoxRepr = transmute(copy box);
     while box != mut_null() {
         let next_before = transmute(copy (*box).header.next);
@@ -151,7 +59,13 @@ unsafe fn each_live_alloc(read_next_before: bool,
 
 #[cfg(unix)]
 fn debug_mem() -> bool {
-    ::rt::env::get().debug_mem
+    use rt;
+    use rt::OldTaskContext;
+    // XXX: Need to port the environment struct to newsched
+    match rt::context() {
+        OldTaskContext => ::rt::env::get().debug_mem,
+        _ => false
+    }
 }
 
 #[cfg(windows)]
@@ -173,13 +87,12 @@ unsafe fn call_drop_glue(tydesc: *TyDesc, data: *i8) {
 }
 
 /// Destroys all managed memory (i.e. @ boxes) held by the current task.
-#[cfg(not(test))]
-#[lang="annihilate"]
 pub unsafe fn annihilate() {
-    use unstable::lang::local_free;
+    use rt::local_heap::local_free;
     use io::WriterUtil;
     use io;
     use libc;
+    use rt::borrowck;
     use sys;
     use managed;
 
@@ -191,7 +104,7 @@ pub unsafe fn annihilate() {
 
     // Quick hack: we need to free this list upon task exit, and this
     // is a convenient place to do it.
-    clear_task_borrow_list();
+    borrowck::clear_task_borrow_list();
 
     // Pass 1: Make all boxes immortal.
     //
@@ -213,7 +126,7 @@ pub unsafe fn annihilate() {
     // callback, as the original value may have been freed.
     for each_live_alloc(false) |box, uniq| {
         if !uniq {
-            let tydesc = (*box).header.type_desc;
+            let tydesc: *TyDesc = transmute(copy (*box).header.type_desc);
             let data = transmute(&(*box).data);
             call_drop_glue(tydesc, data);
         }

src/libstd/comm.rs

@@ -220,48 +220,58 @@ impl<T: Send> Peekable<T> for PortSet<T> {
 
 /// A channel that can be shared between many senders.
 pub struct SharedChan<T> {
-    ch: Exclusive<pipesy::Chan<T>>
+    inner: Either<Exclusive<pipesy::Chan<T>>, rtcomm::SharedChan<T>>
 }
 
 impl<T: Send> SharedChan<T> {
     /// Converts a `chan` into a `shared_chan`.
     pub fn new(c: Chan<T>) -> SharedChan<T> {
         let Chan { inner } = c;
         let c = match inner {
-            Left(c) => c,
-            Right(_) => fail!("SharedChan not implemented")
+            Left(c) => Left(exclusive(c)),
+            Right(c) => Right(rtcomm::SharedChan::new(c))
         };
-        SharedChan { ch: exclusive(c) }
+        SharedChan { inner: c }
     }
 }
 
 impl<T: Send> GenericChan<T> for SharedChan<T> {
     fn send(&self, x: T) {
-        unsafe {
-            let mut xx = Some(x);
-            do self.ch.with_imm |chan| {
-                let x = replace(&mut xx, None);
-                chan.send(x.unwrap())
+        match self.inner {
+            Left(ref chan) => {
+                unsafe {
+                    let mut xx = Some(x);
+                    do chan.with_imm |chan| {
+                        let x = replace(&mut xx, None);
+                        chan.send(x.unwrap())
+                    }
+                }
             }
+            Right(ref chan) => chan.send(x)
         }
     }
 }
 
 impl<T: Send> GenericSmartChan<T> for SharedChan<T> {
     fn try_send(&self, x: T) -> bool {
-        unsafe {
-            let mut xx = Some(x);
-            do self.ch.with_imm |chan| {
-                let x = replace(&mut xx, None);
-                chan.try_send(x.unwrap())
+        match self.inner {
+            Left(ref chan) => {
+                unsafe {
+                    let mut xx = Some(x);
+                    do chan.with_imm |chan| {
+                        let x = replace(&mut xx, None);
+                        chan.try_send(x.unwrap())
+                    }
+                }
             }
+            Right(ref chan) => chan.try_send(x)
         }
     }
 }
 
 impl<T: Send> ::clone::Clone for SharedChan<T> {
     fn clone(&self) -> SharedChan<T> {
-        SharedChan { ch: self.ch.clone() }
+        SharedChan { inner: self.inner.clone() }
     }
 }