nortti
/
edlin
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

More generic macros for specific encodings

This commit is contained in:
Juhani Krekelä 2021-07-30 16:18:10 +03:00
parent d47321c53b
commit 21c3c59489
1 changed files with 38 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

73
edlin.asm
View File

@ -21,36 +21,39 @@ sys_set_dta equ 0x1a
sys_block_read equ 0x27
; Special instruction encodings
%macro add_cx_ax 0
db 0x03, 0xC8 ; add cx, ax (direction swapped)
%endmacro
%macro add_di_cx 0
db 0x03, 0xF9 ; 023E add di, cx (direction swapped)
%endmacro
%define r_ax 0
%define r_cx 1
%define r_dx 2
%define r_bx 3
%define r_sp 4
%define r_bp 5
%define r_si 6
%define r_di 7
%macro sub_cx_di 0
db 0x2b, 0xcf ; sub cx, di (direction swapped)
%endmacro
%define r_al 0
%define r_cl 1
%define r_dl 2
%define r_bl 3
%define r_ah 4
%define r_ch 5
%define r_dh 6
%define r_bh 7
%macro or_al_al 0
db 0x0a, 0xc0 ; or al, al (direction swapped)
; Direction swapped reg, reg
%macro addw 2
db 0x03, 0xc0 + 8 * %1 + %2
%endmacro
%macro xor_ax_ax 0
db 0x33, 0xc0 ; xor ax, ax (direction swapped)
%macro orb 2
db 0x0a, 0xc0 + 8 * %1 + %2
%endmacro
%macro mov_ax_cx 0
db 0x8b, 0xc1 ; mov ax, cx (direction swapped)
%macro subw 2
db 0x2b, 0xc0 + 8 * %1 + %2
%endmacro
%macro mov_dx_cx 0
db 0x8b, 0xD1 ; mov dx, cx (direction swapped)
%macro xorw 2
db 0x33, 0xc0 + 8 * %1 + %2
%endmacro
%macro mov_di_cx 0
db 0x8b, 0xf9 ; mov di, cx (direction swapped)
%endmacro
%macro mov_di_dx 0
db 0x8b, 0xfa ; mov di, dx (direction swapped)
%macro movw 2
db 0x8b, 0xc0 + 8 * %1 + %2
%endmacro
%macro cmp_byteaddr_bytext 2
@ -84,7 +87,7 @@ ensure_file_argument:
je print_filename_missing_error
; AL at program start a flag of whether drive specifier in first parameter valid
or_al_al
orb r_al, r_al
mov dx, invalid_name_error
jnz _trampoline_error_1
@ -100,7 +103,7 @@ open_file:
int 0x21
mov [new_file_flag], al
or_al_al
orb r_al, r_al
jz delete_old_bak
mov dx, new_file_str
@ -130,7 +133,7 @@ delete_old_bak: ; 01b9
mov ah, sys_create_file
int 0x21
or_al_al
orb r_al, r_al
jz setup_file_parameters
mov dx, directory_full_error
@ -141,7 +144,7 @@ print_bak_error: ; 01e6
jmp error
setup_file_parameters: ; 01ec
xor_ax_ax
xorw r_ax, r_ax
mov [psp_fcb_1 + fcb_record_low], ax
mov [psp_fcb_1 + fcb_record_high], ax
mov [__0a58_fcb + fcb_record_low], ax
@ -152,7 +155,7 @@ setup_file_parameters: ; 01ec
mov [__0a58_fcb + fcb_record_size], ax
mov dx, disk_transfer_area
mov_di_dx
movw r_di, r_dx
mov ah, sys_set_dta
int 0x21
@ -168,13 +171,13 @@ setup_file_parameters: ; 01ec
; __0a94 = ¼ available memory
shr cx, 1
mov_ax_cx
movw r_ax, r_cx
shr cx, 1
mov [__0a94], cx
; cx = ¾ available memory
add_cx_ax
addw r_cx, r_ax
mov_dx_cx
movw r_dx, r_cx
add dx, disk_transfer_area
mov [__0a96], dx
@ -183,7 +186,7 @@ read_file:
mov ah, sys_block_read
int 0x21
call find_file_end_char
add_di_cx
addw r_di, r_cx
__0240:
db 0xFC ; 0240 cld
@ -313,11 +316,11 @@ find_file_end_char: ; 035e
mov al, 0x1a ; ^Z
repne scasb
mov_di_cx
movw r_di, r_cx
pop cx
lahf
sub_cx_di
subw r_cx, r_di
sahf
pop di