diff options
Diffstat (limited to 'jefs.s')
| -rw-r--r-- | jefs.s | 69 |
1 files changed, 69 insertions, 0 deletions
@@ -68,18 +68,87 @@ _start: mov rax, __NR_exit syscall +defword "bye", bye, 0 + mov rdi, 0 + mov rax, __NR_exit + syscall + ret ; will not be reached + defword "@", fetch, 0 pspop r11 mov r12, qword [r11] pspush r12 ret +defword "c@", cfetch, 0 + pspop r11 + xor r12, r12 + mov r12b, [r11] + pspush r12 + ret + defword "!", store, 0 pspop r11 pspop r12 mov qword [r11], r12 ret +defword "c!", cstore, 0 + pspop r11 + pspop r12 + mov [r11], r12b + ret + +; stage 1 parser. very rudimentary, does not recognise numbers, +; only recognises newlines and spaces as whitespace. +; since it will only parse a little bit of the init file +; there won't be any error checking either. +defword "parse", parse, 0 + mov r13, qword [to_in] + add r13, initfile + mov r12b, byte [r13] + +.wsloop: ; skip initial ws + cmp r12b, 0x20 + je .wsloop_cont + cmp r12b, 0x0a + jne .wordloop_start +.wsloop_cont: + inc r13 + mov r12b, byte [r13] + jmp .wsloop + +.wordloop_start: + push r13 ; keep start address of this word for later + mov r11, 1 ; W: word length count +.wordloop: + cmp r12b, 0x20 + je .wordloop_end + cmp r12b, 0x0a + je .wordloop_end + + inc r11 + inc r13 + mov r12b, byte [r13] + jmp .wordloop + +.wordloop_end: + sub r13, initfile + mov qword [to_in], r13 + pop r13 + pspush r13 ; c-addr + pspush r11 ; u + ret + +defword "find", find, 0 + ret + +; stage 1 interpreter, just reads from initfile +defword "interpret", interpret, 0 + ret + +defvar ">in", to_in, 0, initfile + initfile: incbin "jefs.fs" initlen equ $ - initfile |