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// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#[doc(hidden)];
use libc::{c_char, c_void, intptr_t, uintptr_t};
use ptr::mut_null;
use repr::BoxRepr;
use sys::TypeDesc;
use cast::transmute;
#[cfg(notest)] use ptr::to_unsafe_ptr;
/**
* Runtime structures
*
* NB: These must match the representation in the C++ runtime.
*/
type DropGlue<'self> = &'self fn(**TypeDesc, *c_void);
type FreeGlue<'self> = &'self fn(**TypeDesc, *c_void);
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")]
#[cfg(target_arch="arm")]
struct Registers {
data: [u32, ..16]
}
#[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
}
/*
* Box annihilation
*
* This runs at task death to free all boxes.
*/
struct AnnihilateStats {
n_total_boxes: uint,
n_unique_boxes: uint,
n_bytes_freed: uint
}
unsafe fn each_live_alloc(f: &fn(box: *mut BoxRepr, uniq: bool) -> bool) {
use managed;
let task: *Task = transmute(rustrt::rust_get_task());
let box = (*task).boxed_region.live_allocs;
let mut box: *mut BoxRepr = transmute(copy box);
while box != mut_null() {
let next = transmute(copy (*box).header.next);
let uniq =
(*box).header.ref_count == managed::raw::RC_MANAGED_UNIQUE;
if ! f(box, uniq) {
break
}
box = next
}
}
#[cfg(unix)]
fn debug_mem() -> bool {
::rt::env::get().debug_mem
}
#[cfg(windows)]
fn debug_mem() -> bool {
false
}
/// Destroys all managed memory (i.e. @ boxes) held by the current task.
#[cfg(notest)]
#[lang="annihilate"]
pub unsafe fn annihilate() {
use unstable::lang::local_free;
use io::WriterUtil;
use io;
use libc;
use sys;
use managed;
let mut stats = AnnihilateStats {
n_total_boxes: 0,
n_unique_boxes: 0,
n_bytes_freed: 0
};
// Pass 1: Make all boxes immortal.
for each_live_alloc |box, uniq| {
stats.n_total_boxes += 1;
if uniq {
stats.n_unique_boxes += 1;
} else {
(*box).header.ref_count = managed::raw::RC_IMMORTAL;
}
}
// Pass 2: Drop all boxes.
for each_live_alloc |box, uniq| {
if !uniq {
let tydesc: *TypeDesc = transmute(copy (*box).header.type_desc);
let drop_glue: DropGlue = transmute(((*tydesc).drop_glue, 0));
drop_glue(to_unsafe_ptr(&tydesc), transmute(&(*box).data));
}
}
// Pass 3: Free all boxes.
for each_live_alloc |box, uniq| {
if !uniq {
stats.n_bytes_freed +=
(*((*box).header.type_desc)).size
+ sys::size_of::<BoxRepr>();
local_free(transmute(box));
}
}
if debug_mem() {
// We do logging here w/o allocation.
let dbg = libc::STDERR_FILENO as io::fd_t;
dbg.write_str("annihilator stats:");
dbg.write_str("\n total_boxes: ");
dbg.write_uint(stats.n_total_boxes);
dbg.write_str("\n unique_boxes: ");
dbg.write_uint(stats.n_unique_boxes);
dbg.write_str("\n bytes_freed: ");
dbg.write_uint(stats.n_bytes_freed);
dbg.write_str("\n");
}
}
/// Bindings to the runtime
pub mod rustrt {
use libc::c_void;
#[link_name = "rustrt"]
pub extern {
#[rust_stack]
// FIXME (#4386): Unable to make following method private.
pub unsafe fn rust_get_task() -> *c_void;
}
}
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