60 lines
1.5 KiB
Rust
60 lines
1.5 KiB
Rust
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#![feature(allocator)]
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#![feature(const_fn)]
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#![allocator]
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#![no_std]
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use spin::Mutex;
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use linked_list_allocator::Heap;
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extern crate spin;
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extern crate linked_list_allocator;
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#[macro_use]
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extern crate lazy_static;
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pub const HEAP_START: usize = 0x1_0000_0000; // Put at end of 4GB
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pub const HEAP_SIZE: usize = 16 * 1024 * 1024; // 16 MB
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lazy_static! {
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static ref HEAP: Mutex<Heap> = Mutex::new(unsafe {
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Heap::new(HEAP_START, HEAP_SIZE)
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});
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}
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#[no_mangle]
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pub extern fn __rust_allocate(size: usize, align: usize) -> *mut u8 {
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HEAP.lock().allocate_first_fit(size, align).expect("out of memory")
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}
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#[no_mangle]
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pub extern fn __rust_deallocate(ptr: *mut u8, size: usize, align: usize) {
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unsafe { HEAP.lock().deallocate(ptr, size, align) };
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}
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#[no_mangle]
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pub extern fn __rust_usable_size(size: usize, _align: usize) -> usize {
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size
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}
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#[no_mangle]
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pub extern fn __rust_reallocate_inplace(_ptr: *mut u8, size: usize,
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_new_size: usize, _align: usize) -> usize
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{
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size
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}
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#[no_mangle]
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pub extern fn __rust_reallocate(ptr: *mut u8, size: usize, new_size: usize,
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align: usize) -> *mut u8 {
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use core::{ptr, cmp};
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// from: https://github.com/rust-lang/rust/blob/
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// c66d2380a810c9a2b3dbb4f93a830b101ee49cc2/
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// src/liballoc_system/lib.rs#L98-L101
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let new_ptr = __rust_allocate(new_size, align);
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unsafe { ptr::copy(ptr, new_ptr, cmp::min(size, new_size)) };
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__rust_deallocate(ptr, size, align);
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new_ptr
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}
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