defer 목록을 '스코프가 아직 갚아야 할 것' 목록으로 일반화했다. defer 블록과 소유 값 해제가 같은 목록에 쓰인 순서대로 들어가고, 모든 이탈 경로가 역순으로 갚는다. 해제에는 값 옆에 플래그를 둔다. 값이 저장될 때 세우고 넘겨줄 때 지운다. 값이 아직 여기 있는 경로에서만 해제되는데, 그건 코드의 모양만 봐서는 알 수 없는 것이다. 검사기가 소유권을 넘기는 사용을 이미 표시해두므로 그것을 읽는다. !void 함수의 빈 return 은 성공이다. 줄 값도 없고 오류도 없다는 뜻인데 프론트엔드가 타입 불일치로 거부하고 있었다. 런타임이 할당/해제 횟수를 센다. owndrop 프로그램이 그 둘이 일치함을 실행으로 증명한다 -- 이른 반환, 이미 넘긴 값, 스코프 끝 전부.
232 lines
5.6 KiB
NASM
232 lines
5.6 KiB
NASM
; Ferro runtime: process entry and the trap handler.
|
|
;
|
|
; The entry point calls the program's `main` and hands its result to
|
|
; ExitProcess, so a Ferro program is an ordinary console executable.
|
|
; `fe_trap` prints where the program stopped and why, then exits 3.
|
|
|
|
.386
|
|
.model flat
|
|
|
|
extern _ExitProcess@4 : near
|
|
extern _GetStdHandle@4 : near
|
|
extern _WriteFile@20 : near
|
|
extern fe_main_ : near
|
|
|
|
_DATA segment dword public 'DATA'
|
|
|
|
reasons dd offset r_bounds, offset r_overflow, offset r_divide
|
|
dd offset r_unreach, offset r_explicit
|
|
r_bounds db 'index out of bounds',0
|
|
r_overflow db 'integer overflow',0
|
|
r_divide db 'divide by zero',0
|
|
r_unreach db 'reached unreachable code',0
|
|
r_explicit db 'trap',0
|
|
r_unknown db 'trap',0
|
|
prefix db 'ferro: ',0
|
|
at_word db ' at ',0
|
|
colon db ':',0
|
|
newline db 13,10,0
|
|
numbuf db 16 dup(0)
|
|
written dd 0
|
|
allocs dd 0
|
|
frees dd 0
|
|
|
|
_DATA ends
|
|
|
|
_TEXT segment dword public 'CODE'
|
|
|
|
; write_cstr(esi = pointer to a NUL-terminated string) -> void
|
|
write_cstr proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
push ebx
|
|
push esi
|
|
push edi
|
|
mov edi, esi
|
|
xor ecx, ecx
|
|
count_loop:
|
|
cmp byte ptr [edi], 0
|
|
je count_done
|
|
inc edi
|
|
inc ecx
|
|
jmp count_loop
|
|
count_done:
|
|
test ecx, ecx
|
|
je write_done
|
|
push -11 ; STD_ERROR_HANDLE
|
|
call _GetStdHandle@4
|
|
push 0 ; lpOverlapped
|
|
push offset written
|
|
push ecx
|
|
push esi
|
|
push eax
|
|
call _WriteFile@20
|
|
write_done:
|
|
pop edi
|
|
pop esi
|
|
pop ebx
|
|
mov esp, ebp
|
|
pop ebp
|
|
ret
|
|
write_cstr endp
|
|
|
|
; write_uint(eax = value) -> void
|
|
write_uint proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
push ebx
|
|
mov edi, offset numbuf + 15
|
|
mov byte ptr [edi], 0
|
|
mov ebx, 10
|
|
digit_loop:
|
|
xor edx, edx
|
|
div ebx
|
|
add dl, '0'
|
|
dec edi
|
|
mov [edi], dl
|
|
test eax, eax
|
|
jnz digit_loop
|
|
mov esi, edi
|
|
call write_cstr
|
|
pop ebx
|
|
mov esp, ebp
|
|
pop ebp
|
|
ret
|
|
write_uint endp
|
|
|
|
; fe_trap(reason, file, line) -- cdecl, never returns
|
|
public fe_trap
|
|
fe_trap proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
mov esi, offset prefix
|
|
call write_cstr
|
|
mov eax, [ebp+8] ; reason
|
|
cmp eax, 5
|
|
jb reason_ok
|
|
mov esi, offset r_unknown
|
|
jmp reason_write
|
|
reason_ok:
|
|
mov esi, [reasons + eax*4]
|
|
reason_write:
|
|
call write_cstr
|
|
mov esi, offset at_word
|
|
call write_cstr
|
|
mov esi, [ebp+12] ; file
|
|
call write_cstr
|
|
mov esi, offset colon
|
|
call write_cstr
|
|
mov eax, [ebp+16] ; line
|
|
call write_uint
|
|
mov esi, offset newline
|
|
call write_cstr
|
|
push 3
|
|
call _ExitProcess@4
|
|
fe_trap endp
|
|
|
|
; ---------------------------------------------------------------- primitives
|
|
; The standard library is written in Ferro; these are the few things it cannot
|
|
; say for itself. All cdecl.
|
|
|
|
extern _GetProcessHeap@0 : near
|
|
extern _HeapAlloc@12 : near
|
|
extern _HeapFree@12 : near
|
|
|
|
; fe_rt_write(handle, ptr, len) -> bytes written
|
|
public fe_rt_write
|
|
fe_rt_write proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
push ebx
|
|
mov eax, [ebp+8] ; 1 = stdout, 2 = stderr
|
|
cmp eax, 2
|
|
je pick_err
|
|
push -11
|
|
jmp pick_done
|
|
pick_err:
|
|
push -12
|
|
pick_done:
|
|
call _GetStdHandle@4
|
|
push 0
|
|
push offset written
|
|
push dword ptr [ebp+16]
|
|
push dword ptr [ebp+12]
|
|
push eax
|
|
call _WriteFile@20
|
|
mov eax, [written]
|
|
pop ebx
|
|
mov esp, ebp
|
|
pop ebp
|
|
ret
|
|
fe_rt_write endp
|
|
|
|
; fe_rt_alloc(n) -> pointer, or zero
|
|
public fe_rt_alloc
|
|
fe_rt_alloc proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
call _GetProcessHeap@0
|
|
push dword ptr [ebp+8]
|
|
push 8 ; HEAP_ZERO_MEMORY
|
|
push eax
|
|
call _HeapAlloc@12
|
|
inc dword ptr [allocs]
|
|
mov esp, ebp
|
|
pop ebp
|
|
ret
|
|
fe_rt_alloc endp
|
|
|
|
; fe_rt_free(p)
|
|
public fe_rt_free
|
|
fe_rt_free proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
mov eax, [ebp+8]
|
|
test eax, eax
|
|
je free_done
|
|
call _GetProcessHeap@0
|
|
push dword ptr [ebp+8]
|
|
push 0
|
|
push eax
|
|
call _HeapFree@12
|
|
inc dword ptr [frees]
|
|
free_done:
|
|
mov esp, ebp
|
|
pop ebp
|
|
ret
|
|
fe_rt_free endp
|
|
|
|
; fe_rt_allocs() / fe_rt_frees() -- what the allocator has been asked to do,
|
|
; so that a test can insist every allocation was released.
|
|
public fe_rt_allocs
|
|
fe_rt_allocs proc near
|
|
mov eax, [allocs]
|
|
ret
|
|
fe_rt_allocs endp
|
|
|
|
public fe_rt_frees
|
|
fe_rt_frees proc near
|
|
mov eax, [frees]
|
|
ret
|
|
fe_rt_frees endp
|
|
|
|
; fe_rt_exit(code) -- never returns
|
|
public fe_rt_exit
|
|
fe_rt_exit proc near
|
|
push ebp
|
|
mov ebp, esp
|
|
push dword ptr [ebp+8]
|
|
call _ExitProcess@4
|
|
fe_rt_exit endp
|
|
|
|
public fe_start_
|
|
fe_start_ proc near
|
|
call fe_main_
|
|
push eax
|
|
call _ExitProcess@4
|
|
fe_start_ endp
|
|
|
|
_TEXT ends
|
|
|
|
end fe_start_
|