holey-bytes/hbxrt/src/mem.rs

48 lines
1.1 KiB
Rust

use std::alloc::Layout;
use hbvm::mem::{Address, LoadError, Memory, StoreError};
pub struct HostMemory;
impl Memory for HostMemory {
#[inline]
unsafe fn load(
&mut self,
addr: Address,
target: *mut u8,
count: usize,
) -> Result<(), LoadError> {
unsafe { core::ptr::copy(addr.get() as *const u8, target, count) }
Ok(())
}
#[inline]
unsafe fn store(
&mut self,
addr: Address,
source: *const u8,
count: usize,
) -> Result<(), StoreError> {
unsafe { core::ptr::copy(source, addr.get() as *mut u8, count) }
Ok(())
}
#[inline]
unsafe fn prog_read<T: Copy>(&mut self, addr: Address) -> T {
unsafe { core::ptr::read(addr.get() as *const T) }
}
}
const STACK_SIZE: usize = 2; // MiB
type Stack = [u8; 1024 * 1024 * STACK_SIZE];
/// Allocate stack of size [`STACK_SIZE`] MiB
pub unsafe fn alloc_stack() -> Box<Stack> {
let layout = Layout::new::<Stack>();
let ptr = unsafe { std::alloc::alloc(layout) };
if ptr.is_null() {
std::alloc::handle_alloc_error(layout);
}
unsafe { Box::from_raw(ptr.cast()) }
}