(* #define PAGE_SIZE 4096 *)
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(* staload "kernel/bootinfo/multiboot.sats" *)
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(* typedef frame_t = @{ *)
(*   num = size_t *)
(* } *)
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(* typedef frame_allocator_t = @{ *)
(*   next_free_frame = frame_t, *)
(*   current_area = memory_area_t, *)
(*   kernel_start = frame_t, *)
(*   kernel_end = frame_t, *)
(*   multiboot_start = frame_t, *)
(*   multiboot_end = frame_t *)
(* } *)
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(* vtypedef allocptr  = [l : agz] (frame_allocator_t@l , frame_allocator_t@l -<lin,prf> void | ptr l) *)
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(* abst@ype frame_allocator = frame_allocator_t *)
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(* fn containing_address {l : addr} (address : ptr l) :<> frame_t *)
(* fn allocate_frame {l : agz}{k : agz} (bf : !boot_info_t @ k | b : ptr k) :<!ref,!wrt> frame_t *)
(* fn deallocate_frame (p : !allocptr) : void *)
(* (* fn frame_allocator_init(kernel_start: Ptr, kernel_end: Ptr, multiboot_start:Ptr, multiboot_end: Ptr, b : !bootptr) : void *) *)