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3 changed files with 616 additions and 35 deletions

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@ -16,6 +16,7 @@ global strcmp
global strchr
global streq
global memcpy
global memmove
global memswap
global eprint_str
global exit
@ -162,6 +163,7 @@ strcmp:
mov rax, 1
ret
;; a and b may be overlapping
;; Copy bytes from one memory location to another
;; rdi: destination pointer
;; rsi: source pointer
@ -182,7 +184,42 @@ memcpy:
.done:
ret
;; rdi: destination pointer
;; rsi: source pointer
;; rdx: number of bytes to move
memmove:
; if dest < src {
cmp rdi, rsi
jb .forward
; reverse
; for i in (0..n).rev() {
mov r8, rdx
.rev_loop:
cmp r8, 0
je .done
dec r8
; dest[i] = src[i];
mov al, [rsi + r8]
mov [rdi + r8], al
jmp .rev_loop
; }
.forward:
; for i in 0..n {
xor r8, r8
.fwd_loop:
cmp r8, rdx
jge .done
; dest[i] = src[i];
mov al, [rsi + r8]
mov [rdi + r8], al
inc r8
jmp .fwd_loop
; }
.done:
mov rax, rdi
ret
;; a and b must not be overlapping
;; Swap bytes between two memory locations
;; rdi: pointer to first memory location
;; rsi: pointer to second memory location

View file

@ -3,6 +3,7 @@ section .rdata
section .text
extern memcpy
extern memmove
extern memswap
extern oom
extern panic
@ -10,12 +11,18 @@ extern eprint_str
extern allocate
global vec_init
global vec_init_with
global vec_push
global vec_pop
global vec_drop_last
global vec_swap
global vec_remove
global vec_get
global vec_drop
global vec_find
global vec_insert
global vec_insert_sorted
global vec_binary_search_by
global vec_tests
@ -62,6 +69,41 @@ vec_init:
pop rbp
ret
;; Initialize a new vector
;; rdi: pointer to Vec struct
;; rsi: item_size
;; rdx: drop function pointer
;; rcx: capacity
;; fn vec_init_with(vec: *mut Vec, item_size: usize, drop: Option<fn(*mut u8)>, capacity: usize)
vec_init_with:
push rbp
mov rbp, rsp
sub rsp, 0x20
mov [rsp], rdx ; save drop
mov [rsp + 8], rsi ; save item_size
mov [rsp + 16], rcx ; save capacity
push rdi
; (*vec).data = allocate(INIT_CAPACITY);
xor rdx, rdx
mov rax, rcx
mul rsi ; capacity * item_size
mov rdi, rax
call allocate
pop r15
mov [r15], rax
; (*vec).len = 0;
mov qword [r15 + 8], 0
mov rax, [rsp + 8]
mov qword [r15 + 24], rax ; item_size
mov rax, [rsp + 16]
mov qword [r15 + 16], rax ; capacity
mov rax, [rsp]
mov qword [r15 + 32], rax ; drop
add rsp, 0x20
pop rbp
ret
;; rdi: pointer to Vec struct
;; rsi: index
;; fn vec_get(vec: *mut Vec, index: usize) -> *mut u8
@ -87,21 +129,17 @@ vec_get:
;; rdi: pointer to Vec struct
;; rsi: pointer to data to push
;; rdx: size of data to push
;; fn vec_push(vec: *mut Vec, data: &[u8])
vec_push:
push rbp
mov rbp, rsp
; if data.len() != vec.item_size panic();
mov rax, [rdi + 24]
cmp rdx, rax
jne .panic
; let vec, ptr, size;
sub rsp, 24
mov [rsp], rdi ; save vec
mov [rsp + 8], rsi ; save data ptr
mov [rsp + 16], rdx ; save data size
; vec_try_grow(vec, size);
mov rsi, [rdi + 8]
inc rsi
call vec_try_grow
; memcpy(&vec.data[vec.len], data, size);
mov rax, [rsp] ; vec
@ -112,7 +150,8 @@ vec_push:
add rax, rcx ; data + len * item_size
mov rdi, rax ; dest ptr
mov rsi, [rsp + 8] ; data ptr
mov rdx, [rsp + 16] ; data size
mov rax, [rsp] ; vec
mov rdx, [rax + 24] ; item_size
call memcpy
; vec.len += 1;
mov rax, [rsp] ; vec
@ -120,15 +159,31 @@ vec_push:
add rsp, 24
pop rbp
ret
.panic:
call panic
pop rbp
ret
;; rdi: pointer to Vec struct
;; fn vec_pop(vec: *mut Vec)
vec_pop:
push rbp
mov rbp, rsp
; if vec.len == 0 panic();
mov rax, [rdi + 8] ; len
test rax, rax
je .underflow
; vec.len -= 1;
sub rax, 1
mov [rdi + 8], rax
pop rbp
ret
; }
.underflow:
call panic
pop rbp
ret
;; rdi: pointer to Vec struct
;; fn vec_pop(vec: *mut Vec)
vec_drop_last:
push rbp
mov rbp, rsp
; if vec.len == 0 panic();
@ -143,10 +198,10 @@ vec_pop:
test r8, r8
je .ret
; drop(&mut vec.data[vec.len..vec.len + vec.item_size]);
xor rdx, rdx
mul qword [rdi + 24] ; len * item_size
mov rsi, [rdi] ; data
add rax, rsi ; data + len * item_size
mov rdi, rax
mov rdi, [rdi] ; data
add rdi, rax ; data + len * item_size
call r8
.ret:
pop rbp
@ -168,32 +223,35 @@ vec_swap:
push rbx
; let vec, a, b;
sub rsp, 24
mov [rsp], rdi
mov [rsp], rdi ; save vec
; let max_index = max(a, b);
mov rbx, rsi
cmp rbx, rdx
cmovl rbx, rdx
; if (max_index >= vec.len) panic();
mov rax, [rdi + 8] ; len
mov rax, [rdi + 8] ; vec.len
cmp rbx, rax
jge .panic
; a = a * item_size;
mov rax, [rdi + 24] ; item_size
mov rbx, [rdi + 24] ; item_size
mov rax, rdx
xor rdx, rdx
mul rbx ; b * item_size
mov [rsp + 16], rax
; b = b * item_size;
mov rax, rsi
xor rdx, rdx
mul rbx ; a * item_size
mov [rsp + 8], rax
; // SAFETY: a and b must not overlap
; memswap(&mut vec.data.add(a), &mut vec.data.add(b), vec.item_size);
mov rcx, [rdi + 24] ; item_size
lea rdi, [rdi] ; vec.data
mov rdx, [rdi + 24] ; item_size
mov rdi, [rdi] ; vec.data
mov rsi, rdi
add rdi, [rsp + 16] ; data + a
add rsi, [rsp + 24] ; data + b
add rsi, [rsp + 8] ; data + b
call memswap
add rsp, 24
pop rbx
@ -201,8 +259,6 @@ vec_swap:
ret
.panic:
call panic
pop rbx
ret
;; rdi: pointer to Vec struct
@ -211,6 +267,10 @@ vec_swap:
vec_remove:
push rbp
mov rbp, rsp
sub rsp, 0x10
mov [rsp], rdi ; save vec
mov [rsp + 8], rsi ; save index
; if (index >= vec.len) panic();
mov rax, [rdi + 8] ; len
cmp rsi, rax
@ -225,6 +285,7 @@ vec_remove:
; }
; vec.len -= 1;
.remove_last:
mov rdi, [rsp] ; vec
mov rax, [rdi + 8] ; len
sub rax, 1
mov [rdi + 8], rax
@ -234,28 +295,29 @@ vec_remove:
je .ret
; drop(&mut vec.data[vec.len..vec.len + vec.item_size]);
mul qword [rdi + 24] ; len * item_size
lea rdi, [rdi] ; data
mov rdi, [rdi] ; data
add rdi, rax ; data + len * item_size
call r8
; }
.ret:
add rsp, 0x10
pop rbp
ret
.panic:
call panic
pop rbp
ret
;; essentially a reserve() function
;; rdi: pointer to Vec struct
;; fn vec_try_grow(vec: *mut Vec, push_size: usize) -> bool
;; rsi: desired size
;; fn vec_try_grow(vec: *mut Vec, new_size: usize) -> bool
vec_try_grow:
push rbp
mov rbp, rsp
push rbx
mov rax, [rdi + 16] ; capacity
mov rbx, [rdi + 8] ; len
cmp rbx, rax
jg .grow
cmp rsi, rax
jge .grow ; grow if new_size >= capacity
pop rbx
xor rax, rax
pop rbp
@ -336,3 +398,210 @@ vec_drop:
pop r12
pop rbp
ret
;; rdi: pointer to Vec struct
;; rsi: poiter to object to find
;; rdx: compare function fn(ctx: *const (), a: *const T, b: *const T) -> bool
;; rcx: compare_fn context
vec_find:
push rbp
mov rbp, rsp
push r12
sub rsp, 0x28
mov [rsp], rdi ; save vec
mov [rsp + 8], rsi ; save object ptr
mov [rsp + 0x10], rdx ; save compare fn
mov rax, [rdi + 24] ; item_size
mov [rsp + 0x18], rax ; save size
mov [rsp + 0x20], rcx ; save compare fn context
xor r12, r12
.loop:
mov rcx, [rsp]
mov rcx, [rcx + 8]
cmp r12, rcx
jge .not_found
; if compare(&vec.data[i], object) {
mov rdi, [rsp + 0x20] ; compare fn context
mov rsi, [rsp + 0x8]
mov rax, [rsp + 0x18] ; size
xor rdx, rdx
mul r12 ; i * item_size
mov rdx, [rsp] ; vec
mov rdx, [rdx] ; vec.data
add rdx, rax ; vec.data + i * item_size
mov rax, [rsp + 0x10] ; compare fn
call rax
test rax, rax
jne .found
; }
inc r12
jmp .loop
.not_found:
mov rax, -1
jmp .epilogue
.found:
mov rax, r12
.epilogue:
add rsp, 0x28
pop r12
pop rbp
ret
;; rdi: pointer to Vec struct
;; rsi : index
;; rdx: pointer to data to insert
;; fn vec_insert(vec: *mut Vec, index: usize, data: *const T, size: usize)
vec_insert:
push rbp
mov rbp, rsp
push r12
push rbx
sub rsp, 0x20
mov [rsp], rdi ; save vec
mov [rsp + 8], rsi ; save index
mov [rsp + 0x10], rdx ; save data ptr
mov rsi, [rdi + 8]
inc rsi
call vec_try_grow
mov rbx, [rsp] ; vec
mov rdi, [rbx] ; vec.data
mov rcx, [rbx + 24] ; item_size
mov rdx, [rbx + 8] ; len
sub rdx, [rsp + 8] ; len - index
mov rax, rdx
mul rcx ; (len - index) * item_size
mov r12, rax ; number of bytes to move
mov rsi, [rbx] ; vec.data
mov rax, [rsp + 8] ; index
mov rcx, [rbx + 24] ; item_size
mul rcx ; index * item_size
add rsi, rax ; src ptr
mov rdi, rsi
add rdi, rcx ; dst ptr
mov rdx, r12 ; number of bytes to move
call memmove
mov rdi, rsi
mov rsi, [rsp + 0x10]
mov rdx, [rbx + 24] ; item_size
call memcpy
mov rax, [rbx + 8] ; len
inc rax
mov [rbx + 8], rax
add rsp, 32
pop rbx
pop r12
pop rbp
ret
;; rdi: pointer to Vec struct
;; rsi: pointer to key
;; rdx: compare function fn(ctx: *const (), a: *const T, b: *const T) -> i32
;; rcx: compare_fn context
;;fn vec_binary_search_by(vec: *mut Vec, key: *const T, compare: fn(ctx: *const (), a: *const T, b: *const T) -> i32, ctx: *const ()) -> (usize, bool)
vec_binary_search_by:
push rbp
mov rbp, rsp
sub rsp, 0x40
mov [rsp], rdi ; save vec
mov [rsp + 0x8], rsi ; save key
mov [rsp + 0x10], rdx ; save compare fn
mov [rsp + 0x18], rcx ; save compare fn context
mov rax, [rdi + 8] ; len
dec rax ; high
mov qword [rsp + 0x20], 0 ; low
mov [rsp + 0x28], rax ; mid
mov [rsp + 0x30], rax ; high
mov rax, [rdi + 24] ; item_size
mov [rsp + 0x38], rax ; item_size
.loop:
mov rax, [rsp + 0x20] ; low
mov rcx, [rsp + 0x30] ; high
cmp rax, rcx
jg .not_found
; mid = (low + high) / 2
sub rcx, rax
shr rcx, 1
add rax, rcx
mov [rsp + 0x28], rax ; mid
mov rcx, [rsp] ; vec
mov rcx, [rcx] ; vec.data
mov rdx, [rsp + 0x38] ; item_size
mul rdx ; mid * item_size
add rax, rcx ; vec.data + mid * item_size
mov rdi, [rsp + 0x18] ; compare ctx
mov rsi, [rsp + 0x8] ; key
mov rdx, rax
mov rax, [rsp + 0x10] ; compare fn
call rax
cmp eax, 0
je .found
jl .less
; greater
mov rax, [rsp + 0x28] ; mid
inc rax
mov [rsp + 0x28], rax ; mid
mov [rsp + 0x20], rax ; low = mid + 1
jmp .loop
.less:
mov rax, [rsp + 0x28] ; mid
cmp rax, 0
je .not_found ; if mid == 0, not found
dec rax
mov [rsp + 0x30], rax ; high = mid - 1
jmp .loop
.found:
mov rax, [rsp + 0x28]
xor rdx, rdx
jmp .epilogue
.not_found:
mov rax, [rsp + 0x28]
mov rdx, 1
.epilogue:
add rsp, 0x40
pop rbp
ret
;; rdi: pointer to Vec struct
;; rsi: pointer to key
;; rdx: compare function fn(ctx: *const (), a: *const T, b: *const T) -> i32
;; rcx: compare_fn context
;;fn vec_insert_sorted(vec: *mut Vec, key: *const T, compare: fn(ctx: *const (), a: *const T, b: *const T) -> i32, ctx: *const ()) -> (usize, bool)
vec_insert_sorted:
push rbp
mov rbp, rsp
sub rsp, 0x18
mov [rsp], rdi ; vec
mov [rsp + 8], rsi ; element ptr
call vec_binary_search_by
test rdx, rdx
jnz .insert
; element already exists
jmp .epilogue
.insert:
mov [rsp + 0x10], rax ; index
mov rdi, [rsp] ; vec
mov rsi, rax ; index
mov rdx, [rsp + 8] ; element ptr
call vec_insert
mov rax, [rsp + 0x10] ; index
mov rdx, 1 ; indicate inserted
.epilogue:
add rsp, 0x18
pop rbp
ret

View file

@ -7,6 +7,210 @@ pub struct BlobVec {
pub drop: Option<extern "C" fn(*mut u8)>,
}
struct VecT<T> {
vec: BlobVec,
_marker: core::marker::PhantomData<T>,
}
impl<T> VecT<T> {
fn new() -> Self {
Self::new_with(32)
}
fn new_with(capacity: usize) -> Self {
let mut vec = BlobVec {
data: core::ptr::null_mut(),
len: 0,
cap: 0,
elem_size: 0,
drop: None,
};
extern "C" fn drop_fn<T>(ptr: *mut u8) {
unsafe {
core::ptr::drop_in_place::<T>(ptr as *mut T);
}
}
unsafe {
vec_init_with(
&mut vec,
core::mem::size_of::<T>(),
Some(drop_fn::<T>),
capacity,
);
}
Self {
vec,
_marker: core::marker::PhantomData,
}
}
fn as_slice(&self) -> &[T] {
assert_eq!(self.vec.elem_size, core::mem::size_of::<T>());
unsafe { core::slice::from_raw_parts(self.vec.data as *const T, self.vec.len) }
}
fn as_slice_mut(&mut self) -> &mut [T] {
assert_eq!(self.vec.elem_size, core::mem::size_of::<T>());
unsafe { core::slice::from_raw_parts_mut(self.vec.data as *mut T, self.vec.len) }
}
fn push(&mut self, value: T) {
let value = core::mem::ManuallyDrop::new(value);
unsafe {
vec_push(&mut self.vec, &raw const value as *const T as *const u8);
}
}
fn insert(&mut self, value: T, index: usize) {
if index > self.vec.len {
return;
}
let value = core::mem::ManuallyDrop::new(value);
unsafe {
vec_insert(
&mut self.vec,
index,
&raw const value as *const T as *const u8,
);
}
}
fn pop(&mut self) -> Option<T> {
if self.vec.len == 0 {
return None;
}
unsafe {
let ptr = vec_get(&mut self.vec, self.vec.len - 1) as *mut T;
let value = ptr.read();
vec_pop(&mut self.vec);
Some(value)
}
}
fn get(&self, index: usize) -> Option<&T> {
if index >= self.vec.len {
return None;
}
unsafe {
let ptr = vec_get(&raw const self.vec as *mut _, index) as *mut T;
Some(&*ptr)
}
}
fn get_mut(&mut self, index: usize) -> Option<&mut T> {
if index >= self.vec.len {
return None;
}
unsafe {
let ptr = vec_get(&raw mut self.vec, index) as *mut T;
Some(&mut *ptr)
}
}
fn remove(&mut self, index: usize) {
if index >= self.vec.len {
return;
}
unsafe {
vec_remove(&mut self.vec, index);
}
}
fn len(&self) -> usize {
self.vec.len
}
fn position<F>(&self, elem: &T, mut cmp: F) -> Option<usize>
where
F: FnMut(&T, &T) -> bool,
{
extern "C" fn cmp_trampoline<T, F: FnMut(&T, &T) -> bool>(
f: *const (),
a: *const u8,
b: *const u8,
) -> bool {
let f = unsafe { &mut *(f as *mut F) };
let a = unsafe { &*(a as *const T) };
let b = unsafe { &*(b as *const T) };
f(a, b)
}
unsafe {
let index = vec_find(
&raw const self.vec as *mut _,
elem as *const T as *const u8,
cmp_trampoline::<T, F>,
&raw mut cmp as *mut F as *mut (),
);
if index == usize::MAX {
None
} else {
Some(index)
}
}
}
fn binary_search_by<F>(&self, elem: &T, mut cmp: F) -> Result<usize, usize>
where
F: FnMut(&T, &T) -> i32,
{
extern "C" fn cmp_trampoline<T, F: FnMut(&T, &T) -> i32>(
f: *const (),
a: *const u8,
b: *const u8,
) -> i32 {
let f = unsafe { &mut *(f as *mut F) };
let a = unsafe { &*(a as *const T) };
let b = unsafe { &*(b as *const T) };
f(a, b)
}
unsafe {
let (index, vacant) = vec_binary_search_by(
&raw const self.vec as *mut _,
elem as *const T as *const u8,
cmp_trampoline::<T, F>,
&raw mut cmp as *mut F as *mut (),
);
if vacant {
Err(index)
} else {
Ok(index)
}
}
}
fn insert_sorted<F>(&self, elem: T, mut cmp: F) -> Result<usize, usize>
where
F: FnMut(&T, &T) -> i32,
{
extern "C" fn cmp_trampoline<T, F: FnMut(&T, &T) -> i32>(
f: *const (),
a: *const u8,
b: *const u8,
) -> i32 {
let f = unsafe { &mut *(f as *mut F) };
let a = unsafe { &*(a as *const T) };
let b = unsafe { &*(b as *const T) };
f(a, b)
}
let mut elem = core::mem::ManuallyDrop::new(elem);
unsafe {
let (index, inserted) = vec_insert_sorted(
&raw const self.vec as *mut _,
&raw const elem as *const u8,
cmp_trampoline::<T, F>,
&raw mut cmp as *mut F as *mut (),
);
Ok(index)
}
}
}
#[unsafe(no_mangle)]
extern "C" fn panic() -> ! {
panic!("Called panic from external code.");
@ -17,14 +221,42 @@ unsafe impl Sync for BlobVec {}
unsafe extern "C" {
unsafe fn vec_init(vec: *mut BlobVec, elem_size: usize, drop: Option<extern "C" fn(*mut u8)>);
unsafe fn vec_push(vec: *mut BlobVec, elem: *const u8, size: usize);
unsafe fn vec_init_with(
vec: *mut BlobVec,
elem_size: usize,
drop: Option<extern "C" fn(*mut u8)>,
cap: usize,
);
unsafe fn vec_push(vec: *mut BlobVec, elem: *const u8);
unsafe fn vec_insert(vec: *mut BlobVec, index: usize, elem: *const u8);
unsafe fn vec_pop(vec: *mut BlobVec);
unsafe fn vec_drop_last(vec: *mut BlobVec);
unsafe fn vec_get(vec: *mut BlobVec, index: usize) -> *mut u8;
#[allow(dead_code)]
unsafe fn vec_remove(vec: *mut BlobVec, index: usize);
#[allow(dead_code)]
unsafe fn vec_drop(vec: *mut BlobVec);
unsafe fn vec_find(
vec: *mut BlobVec,
elem: *const u8,
cmp: extern "C" fn(*const (), *const u8, *const u8) -> bool,
cmp_data: *mut (),
) -> usize;
unsafe fn vec_binary_search_by(
vec: *mut BlobVec,
elem: *const u8,
cmp: extern "C" fn(*const (), *const u8, *const u8) -> i32,
cmp_data: *mut (),
) -> (usize, bool);
unsafe fn vec_insert_sorted(
vec: *mut BlobVec,
elem: *const u8,
cmp: extern "C" fn(*const (), *const u8, *const u8) -> i32,
cmp_data: *mut (),
) -> (usize, bool);
}
fn main() {
@ -64,25 +296,68 @@ fn main() {
vec_init(&mut vec, 4, Some(drop));
let mut value: u32 = 2;
assert_eq!(vec.len, 0);
vec_push(&mut vec, &value as *const u32 as *const u8, 4);
vec_push(&mut vec, &value as *const u32 as *const u8);
assert_eq!(vec.len, 1);
assert_eq!(as_slice::<u32>(&vec), &[2]);
let retrieved = *(vec_get(&mut vec, 0) as *mut u32);
assert_eq!(retrieved, 2);
assert_eq!(get_drops(), 1);
vec_pop(&mut vec);
vec_drop_last(&mut vec);
assert_eq!(vec.len, 0);
assert_eq!(get_drops(), 2);
value = 3;
vec_push(&mut vec, &value as *const u32 as *const u8, 4);
vec_push(&mut vec, &value as *const u32 as *const u8);
assert_eq!(as_slice::<u32>(&vec), &[3]);
value = 5;
vec_push(&mut vec, &value as *const u32 as *const u8, 4);
vec_push(&mut vec, &value as *const u32 as *const u8);
assert_eq!(as_slice::<u32>(&vec), &[3, 5]);
assert_eq!(vec.len, 2);
vec_pop(&mut vec);
vec_pop(&mut vec);
vec_drop_last(&mut vec);
vec_drop_last(&mut vec);
assert_eq!(get_drops(), 2 * 3 * 5);
eprintln!("Push/pop test passed\n");
}
let mut vec = VecT::<u32>::new_with(100);
assert_eq!(vec.len(), 0);
vec.push(10);
vec.push(20);
vec.push(30);
assert_eq!(vec.len(), 3);
assert_eq!(vec.get(0), Some(&10));
assert_eq!(vec.get(1), Some(&20));
assert_eq!(vec.get(2), Some(&30));
assert_eq!(vec.pop(), Some(30));
assert_eq!(vec.len(), 2);
vec.remove(0);
assert_eq!(vec.len(), 1);
assert_eq!(vec.get(0), Some(&20));
vec.push(40);
vec.push(50);
assert_eq!(
vec.position(&40, |a, b| {
eprintln!("Comparing {} and {}", a, b);
a == b
}),
Some(1)
);
assert_eq!(vec.as_slice(), &[20, 40, 50]);
vec.insert(30, 1);
assert_eq!(vec.as_slice(), &[20, 30, 40, 50]);
let cmp = |a: &u32, b: &u32| match a.cmp(b) {
core::cmp::Ordering::Less => -1,
core::cmp::Ordering::Equal => 0,
core::cmp::Ordering::Greater => 1,
};
assert_eq!(vec.binary_search_by(&35, cmp), Err(2));
assert_eq!(vec.binary_search_by(&25, cmp), Err(1));
assert_eq!(vec.binary_search_by(&30, cmp), Ok(1));
assert_eq!(vec.binary_search_by(&5, cmp), Err(0));
assert_eq!(vec.binary_search_by(&55, cmp), Err(4));
vec.insert_sorted(35, cmp);
assert_eq!(vec.as_slice(), &[20, 30, 35, 40, 50]);
}