libfringe/src/arch/x86_64/mod.rs

76 lines
2.1 KiB
Rust

// Copyright (c) 2015, edef <edef@edef.eu>
// See the LICENSE file included in this distribution.
use core::prelude::*;
use core::mem::{size_of, align_of};
use core::cmp::max;
use core::ptr;
use stack::Stack;
#[allow(non_camel_case_types)]
pub type uintptr_t = u64;
#[allow(raw_pointer_derive)]
#[derive(Copy, Clone)]
pub struct Registers {
rsp: *mut uintptr_t
}
impl Registers {
#[inline]
pub unsafe fn new<S, F>(stack: &mut S, f: F) -> Registers where S: Stack, F: FnOnce() {
let sp_limit = stack.limit();
let mut sp = stack.top() as *mut uintptr_t;
let f_ptr = push(&mut sp, f);
asm!(include_str!("init.s")
: "={rdi}"(sp)
: "{rdi}" (sp),
"{rsi}" (rust_trampoline::<F>),
"{rdx}" (f_ptr),
"{rcx}" (sp_limit)
:
: "volatile");
Registers { rsp: sp }
}
#[inline(always)]
pub unsafe fn swap(&mut self) {
asm!(include_str!("swap.s")
:
: "{rdi}" (&mut self.rsp)
: "rax", "rbx", "rcx", "rdx", "rsi", "rdi", //"rbp", "rsp",
"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
"xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7",
"xmm8", "xmm9", "xmm10", "xmm11", "xmm12", "xmm13", "xmm14", "xmm15",
"xmm16", "xmm17", "xmm18", "xmm19", "xmm20", "xmm21", "xmm22", "xmm23",
"xmm24", "xmm25", "xmm26", "xmm27", "xmm28", "xmm29", "xmm30", "xmm31"
"cc"
: "volatile");
}
}
unsafe extern "C" fn rust_trampoline<F: FnOnce()>(f: *const F) {
ptr::read(f)()
}
unsafe fn push<T>(spp: &mut *mut uintptr_t, value: T) -> *mut T {
let mut sp = *spp as *mut T;
sp = offset_mut(sp, -1);
sp = align_down_mut(sp, max(align_of::<T>(), 16));
*sp = value;
*spp = sp as *mut uintptr_t;
sp
}
fn align_down_mut<T>(sp: *mut T, n: usize) -> *mut T {
let sp = (sp as usize) & !(n - 1);
sp as *mut T
}
// ptr::offset_mut is positive ints only
pub fn offset_mut<T>(ptr: *mut T, count: isize) -> *mut T {
(ptr as isize + count * (size_of::<T>() as isize)) as *mut T
}