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stack: safe partial commit of mem.rs changes from motes PR

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Alex Shelkovnykov 2024-02-07 18:00:27 +09:00
parent bac7919bd9
commit e086fbd388
1 changed files with 26 additions and 41 deletions
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67
rust/ares/src/mem.rs
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@ -340,58 +340,41 @@ impl NockStack {
} }
} }
unsafe fn struct_alloc_in_previous_frame_west<T>(&mut self, count: usize) -> *mut T { unsafe fn raw_alloc_in_previous_frame_west(&mut self, words: usize) -> *mut u64 {
// note that the allocation is on the east frame, and thus resembles raw_alloc_east // note that the allocation is on the east frame, and thus resembles raw_alloc_east
let alloc = *self.prev_alloc_pointer_pointer(); let alloc = *self.prev_alloc_pointer_pointer();
*(self.prev_alloc_pointer_pointer()) = *(self.prev_alloc_pointer_pointer()) = (*(self.prev_alloc_pointer_pointer())).add(words);
(*(self.prev_alloc_pointer_pointer())).add(word_size_of::<T>() * count);
alloc as *mut T
}
unsafe fn struct_alloc_in_previous_frame_east<T>(&mut self, count: usize) -> *mut T {
// note that the allocation is on the east frame, and thus resembles raw_alloc_west
*(self.prev_alloc_pointer_pointer()) =
(*(self.prev_alloc_pointer_pointer())).sub(word_size_of::<T>() * count);
*(self.prev_alloc_pointer_pointer()) as *mut T
}
/** Allocates space in the previous frame for some number of T's. This calls pre_copy()
* first to ensure that the stack frame is in cleanup phase, which is the only time we
* should be allocating in a previous frame.*/
pub unsafe fn struct_alloc_in_previous_frame<T>(&mut self, count: usize) -> *mut T {
self.pre_copy();
if self.is_west() {
self.struct_alloc_in_previous_frame_west(count)
} else {
self.struct_alloc_in_previous_frame_east(count)
}
}
unsafe fn indirect_alloc_in_previous_frame_west(&mut self, words: usize) -> *mut u64 {
let alloc = *self.prev_alloc_pointer_pointer();
*(self.prev_alloc_pointer_pointer()) =
(*(self.prev_alloc_pointer_pointer())).add(words + 2);
alloc alloc
} }
unsafe fn indirect_alloc_in_previous_frame_east(&mut self, words: usize) -> *mut u64 { unsafe fn raw_alloc_in_previous_frame_east(&mut self, words: usize) -> *mut u64 {
*(self.prev_alloc_pointer_pointer()) = // note that the allocation is on the west frame, and thus resembles raw_alloc_west
(*(self.prev_alloc_pointer_pointer())).sub(words + 2); *(self.prev_alloc_pointer_pointer()) = (*(self.prev_alloc_pointer_pointer())).sub(words);
*self.prev_alloc_pointer_pointer() *(self.prev_alloc_pointer_pointer())
} }
/** Allocate space for an indirect atom in the previous stack frame. This call pre_copy() /** Allocate space in the previous stack frame. This calls pre_copy() first to ensure that the
* first to ensure that the stack frame is in cleanup phase, which is the only time we * stack frame is in cleanup phase, which is the only time we should be allocating in a previous
* should be allocating in a previous frame. */ * frame. */
unsafe fn indirect_alloc_in_previous_frame(&mut self, words: usize) -> *mut u64 { unsafe fn raw_alloc_in_previous_frame(&mut self, words: usize) -> *mut u64 {
self.pre_copy(); self.pre_copy();
if self.is_west() { if self.is_west() {
self.indirect_alloc_in_previous_frame_west(words) self.raw_alloc_in_previous_frame_west(words)
} else { } else {
self.indirect_alloc_in_previous_frame_east(words) self.raw_alloc_in_previous_frame_east(words)
} }
} }
/** Allocates space in the previous frame for some number of T's. */
pub unsafe fn struct_alloc_in_previous_frame<T>(&mut self, count: usize) -> *mut T {
self.raw_alloc_in_previous_frame(word_size_of::<T>() * count) as *mut T
}
/** Allocate space for an indirect atom in the previous stack frame. */
unsafe fn indirect_alloc_in_previous_frame(&mut self, words: usize) -> *mut u64 {
self.raw_alloc_in_previous_frame(words + 2)
}
/** Allocate space for an alloc::Layout in a stack frame */ /** Allocate space for an alloc::Layout in a stack frame */
unsafe fn layout_alloc(&mut self, layout: Layout) -> *mut u64 { unsafe fn layout_alloc(&mut self, layout: Layout) -> *mut u64 {
assert!(layout.align() <= 64, "layout alignment must be <= 64"); assert!(layout.align() <= 64, "layout alignment must be <= 64");
@ -639,6 +622,10 @@ impl NockStack {
/** Push a frame onto the stack with 0 or more local variable slots. */ /** Push a frame onto the stack with 0 or more local variable slots. */
pub fn frame_push(&mut self, num_locals: usize) { pub fn frame_push(&mut self, num_locals: usize) {
if self.pc {
panic!("frame_push during cleanup phase is prohibited.");
}
let current_frame_pointer = self.frame_pointer; let current_frame_pointer = self.frame_pointer;
let current_stack_pointer = self.stack_pointer; let current_stack_pointer = self.stack_pointer;
let current_alloc_pointer = self.alloc_pointer; let current_alloc_pointer = self.alloc_pointer;
@ -655,8 +642,6 @@ impl NockStack {
*(self.slot_pointer(STACK)) = current_stack_pointer as u64; *(self.slot_pointer(STACK)) = current_stack_pointer as u64;
*(self.slot_pointer(ALLOC)) = current_alloc_pointer as u64; *(self.slot_pointer(ALLOC)) = current_alloc_pointer as u64;
} }
self.pc = false;
} }
/** Run a closure inside a frame, popping regardless of the value returned by the closure. /** Run a closure inside a frame, popping regardless of the value returned by the closure.