diff options
| -rw-r--r-- | readme.md | 26 | ||||
| -rw-r--r-- | sanctuary.s | 43 |
2 files changed, 61 insertions, 8 deletions
@@ -23,16 +23,22 @@ store the 64 bit value u into the memory address a. ### `#tib ( -- a )` variable containing the amount of characters in the input buffer. -### `(header) ( a u -- xt )` -create a dictionary header for a word named the provided string. -this word does not set the code field. -this word returns an incompleted xt and does not update latest. - ### `( ( -- ) IMMEDIATE` start a comment which lasts until the next closed bracket. if the unclosed bracket in the description above bothers you, have a closing bracket: ). +### `(0handler) ( -- )` +the very early error handler, which simply quits the program. + +### `(execute) ( a -- )` +call the function at the address. + +### `(header) ( a u -- xt )` +create a dictionary header for a word named the provided string. +this word does not set the code field. +this word returns an incompleted xt and does not update latest. + ### `* ( u1 u2 -- u)` multiply u1 and u2. @@ -143,6 +149,10 @@ remove the two topmost values from the stack. ### `2dup ( u1 u2 -- u1 u2 u1 u2 )` duplicate the two topmost values on the stack. +### `abort ( -- )` +call the error handler +(the address of which is in the variable `handler`) + ### `and ( u1 u2 -- u )` perform bitwise AND on u1 and u2. @@ -209,6 +219,9 @@ marks the u bytes starting at address a as executable. this is used primarily to mark the program break, which is used as the user memory space. +### `execute ( xt -- )` +call the word xt. + ### `find ( a u -- a u 0 | xt -1 )` look in the dictionary for the word a (of u characters). a zero is returned along with the original given string @@ -218,6 +231,9 @@ its xt is returned along with the true flag. ### `grow ( u -- )` grows, and marks as executable, the user memory space by u bytes. +### `handler ( -- a )` +variable containing the address of the current error handler. + ### `here ( -- a )` yields the address of the first available byte in user memory. diff --git a/sanctuary.s b/sanctuary.s index 0d35337..53749cc 100644 --- a/sanctuary.s +++ b/sanctuary.s @@ -1,15 +1,26 @@ ; sanctuary ; macros {{{ -; TODO: error handling (once i add that) +; the error handling feels slow but i dont know a better way +; todo at some point make these use actual error codes %macro pspush 1 lea r15, [r15-8] mov qword [r15], %1 + + cmp r15, wstk_b + jge %%ok + call abort + %%ok: %endmacro %macro pspop 1 mov %1, qword [r15] lea r15, [r15+8] + + cmp r15, wstk + jle %%ok + call abort + %%ok: %endmacro %define s_latest 0 @@ -58,8 +69,8 @@ %assign init_brk 0x9c400 section .bss -resq 4091 -wstk: resq 1 +wstk_b: resq 4091 +wstk: resq 1 section .text global _start @@ -502,6 +513,16 @@ defcode "char", char, 0 pspush r11 ret +defcode "(execute)", do_execute, 0 + pspop r11 + call r11 + ret + +defcode "execute", execute, 0 + call to_body + call do_execute + ret + ; number {{{ defcode "number", number, 0 ; ( c-addr u -- ?n flag ) pspop r11 ; u @@ -965,6 +986,21 @@ defcode "?branch", q_branch, 0 mov qword [here], r12 ret +; error handling {{{ +; default error handler, because we don't have QUIT yet +; it just Exits with exit code 1 +defcode "(0handler)", do_0handler, 0 + mov rdi, 1 + mov rax, __NR_exit + syscall + ret + +defcode "abort", abort, 0 + mov r11, qword [handler] + call r11 + ret +; }}} + ; TEMPORARY WONKY DEBUGGING FUNCTIONS {{{ ; .s {{{ defcode ".s", dots, 0 @@ -1024,6 +1060,7 @@ defvar "dp$", dp$, 0, 0 defvar "tib", tib, 0, initfile defvar "#tib", n_tib, 0, initlen defvar ">in", to_in, 0, 0 +defvar "handler", handler, 0, do_0handler defvar "latest", latest, 0, lfa_latest initfile: incbin "sanctuary.fs" |