diff options
| -rw-r--r-- | readme.md | 46 | ||||
| -rw-r--r-- | sanctuary.s | 69 |
2 files changed, 105 insertions, 10 deletions
@@ -13,14 +13,52 @@ for amd64 linux systems. ## Glossary -the following is a list of words available in this forth. (neither of these have been implemented yet i'm just putting them here in the meantime lol) +the following is a list of words available in this forth. + +### `#tib ( -- a )` +variable containing the amount of characters in the input buffer. + +### `>in ( -- a )` +variable containing the index of the first unparsed character +in the input buffer. + +### `brk@ ( -- a )` +yields current program break. + +### `bye ( -- )` +exits the forth system. ### `dp ( -- a )` -`dp` is a variable that contains the lowest free byte of memory in user memory. +a variable that contains the lowest free byte of memory in user memory. + +### `dp0 ( -- )` +a variable that contains the first byte of user memory. + +### `dp$ ( -- )` +a variable that contains the last available byte of user memory. + +### `executable ( u a -- )` +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. + +### `grow ( u -- )` +grows the user memory space by u bytes. ### `here ( -- a )` -`here` yields the address of the first available byte -in user memory. +yields the address of the first available byte in user memory. + +### `latest ( -- a )` +a variable containing the execution token of +the most recently created word. + +### `state ( -- a )` +a variable containing a boolean value. +if 0 (false), the system is in interpreting mode, +if -1 (true), the system is in compiling mode. + +### `tib ( -- a )` +a variable containing the address of the current input buffer. ## dictionary format diff --git a/sanctuary.s b/sanctuary.s index 5859ac1..b511d68 100644 --- a/sanctuary.s +++ b/sanctuary.s @@ -1,8 +1,6 @@ ; sanctuary ; macros {{{ -; in this forth pspush and pspop are only necessary if you need to -; go deeper into the stack. ; TODO: error handling (once i add that) %macro pspush 1 lea r14, [r14-8] @@ -16,6 +14,10 @@ lea r14, [r14+8] %endmacro +%macro psdrop 0 + lea r14, [r14+8] +%endmacro + %define s_latest 0 %macro defdict 3 ; name label flags @@ -37,14 +39,20 @@ ; to how user variables are planned to work in sanctuary ; so todo make better later? i don't know if it really matters ; because it will only apply to builtin variables. -%macro defvar 3 +%macro defvar 4 %2: dq %4 defdict %1, %2, %3 - ; pspush qword %2 ; todo - %2: + pspush qword %2 %endmacro ; }}} +%assign INTERPRET 0x0 +%assign COMPILING (~0x1) + +%assign __NR_mprotect 10 +%assign __NR_brk 12 +%assign __NR_exit 60 + section .bss resq 4091 wstk: resq 1 @@ -52,6 +60,55 @@ wstk: resq 1 section .text global _start _start: + lea r14, [wstk + 8] + + call brk@ + mov qword [dp], r15 + mov qword [dp0], r15 + mov r15, 0x9c400 + call grow + call bye + +defcode "brk@", brk@, 0 + xor rdi, rdi + mov rax, __NR_brk + syscall + pspush rax + ret + +defcode "grow", grow, 0 + call brk@ + pspop rdi + pspop r13 + add rdi, r13 + mov rax, __NR_brk + syscall + mov qword [dp$], rax + ret + +defcode "executable", executable, 0 + mov rdx, 0x7 ; PROT_{READ,WRITE,EXEC} + pspop rdi ; addr + pspop rsi + mov rax, __NR_mprotect + syscall + ret + +defcode "here", here, 0 + pspush qword [dp] + ret + +defcode "bye", bye, 0 mov rdi, 0 - mov rax, 60 + mov rax, __NR_exit syscall + ret + +defvar "state", state, 0, INTERPRET +defvar "dp", dp, 0, 0 +defvar "dp0", dp0, 0, 0 +defvar "dp$", dp$, 0, 0 +defvar "tib", tib, 0, 0 ; todo set correct initial value +defvar "#tib", n_tib, 0, 0 ; todo set correct initial value +defvar ">in", to_in, 0, 0 +defvar "latest", latest, 0, lfa_latest |