segment readable writable executable
+;;; This is the very first word
+
+ ;; FORTH is the last word of WORDLIST FORTH
+ WORD p_forth,'FORTH',dovalue
+ ;; ( -- )
+ ;; Change to use this wordlist
+ dq last_forth_word
+ dq inline_code
+ mov rax,qword [p_forth_DFA]
+ mov qword [p_wordlist],rax
+ popr rsi
+ next
+
+ WORD p_syscall,'SYSCALL',dodoes,,,8
+ ;; ( -- )
+ ;; Change to use this wordlist
+ dq last_syscall_word
+ dq inline_code
+ mov rax,qword [p_syscall_DFA]
+ mov qword [p_wordlist],rax
+ popr rsi
+ next
+
+last_wordlists_word:
+ WORD p_wordlists,'WORDLISTS',dodoes,,,8
+ ;; ( -- )
+ ;; Change to use this wordlist
+ dq p_wordlists_TFA
+ dq inline_code
+ mov rax,qword [p_wordlists_DFA]
+ mov qword [p_wordlist],rax
+ popr rsi
+ next
+
+include 'wordlists.asm'
+
WORD return_stack,'RS',dovariable
;; The return stack
rb 1048576 ; 1 Mb return stack
;; exit to the calling definition via "jmp exit".
jmp qword rsi
+ WORD p_execute,'EXECUTE',fasm
+ ;; ( tfa -- )
+ ;; Execute the word
+ pop rax
+ tfa2cfa rax
+ jmp qword [rax] ; goto code of that FORTH word (64 bit jump)
+
+ WORD p_exit, 'EXIT',fasm
+ ;; ( -- ) ( R: addr -- )
+ ;; Returns execution to the calling definition as per the
+ ;; return stack.
+exit:
+ popr rsi
+ next
+
+ ;; TERMINATE0 terminates the program with code 0
+ ;; ( -- )
+ WORD terminate, 'TERMINATE0',fasm
+ pop rdx
+terminate_special:
+ mov eax,60
+ syscall
+
+ WORD p_branch,'BRANCH',fasm
+ ;; ( -- )
+ ;; Using subsequent inline cell as branch offset, branch
+ ;; accordingly
+ add rsi,qword [rsi]
+ add rsi,8
+ next
+
+ WORD p_zero_branch,'0BRANCH',fasm
+ ;; ( v -- )
+ ;; Using subsequent inline cell as branch offset, branch
+ ;; accordingly if the stacked value is zero, otherwise just
+ ;; skip over the branch offset
+ pop rax
+ cmp rax,0
+ jne p_zero_branch_SKIP
+ add rsi,qword [rsi]
+p_zero_branch_SKIP:
+ add rsi,8
+ next
+
+;;; Execution semantics for a "fasm" WORD
+dofasm:
+ add rax,8
+ jmp rax
;;; Execution semantics for FORTH defition word
;;; At entry, rsi points into the calling definition, at the cell
;;; following the cell indicating this word, rax points to the CFA of
lea rsi, [rax+8] ; rsi = the DFA of the rax word
next
- WORD p_exit, 'EXIT',fasm
- ;; ( -- ) ( R: addr -- )
- ;; Returns execution to the calling definition as per the
- ;; return stack.
-exit:
- popr rsi
+;;; Execution semantics for DOES>
+;;; The cell at [cfa-8] holds an adjustment offset.
+dodoes:
+ pushr rsi
+ lea rsi, [rax+8] ; rsi = the DFA of the rax word
+ add rsi,[rax-8] ; adjust rsi to the DOES> part
next
;; Execution semantics for a variable ( -- addr )
- ;; rax points to doer field
+ ;; rax points to CFA field
dovariable:
- push rax+16
+ add rax,8
+ push rax
next
;; Execution semantics for a constant ( -- v )
- ;; rax points to doer field
+ ;; rax points to CFA field
dovalue:
- push qword [rax+16]
+ push qword [rax+8]
next
;; Execution semantics for a string constant ( -- addr n )
- ;; rax points to doer field
+ ;; rax points to CFA field
dostring:
- add rax,16
- mov bl,[rax]
- mov byte [rsp],bl
- push rax+1
+ cfa2dfa rax
+ pushpname rax
next
-include 'wordlists.asm'
-include 'syscalls.asm'
include 'memory.asm'
include 'stack.asm'
include 'math.asm'
+include 'logic.asm'
include 'stdio.asm'
+include 'compile.asm'
WORD p_program_version,'PROGRAM_VERSION',dostring
- db length
-program_version_string:
- db 'RRQ Forth version 0.1 - 2021-05-13',10
- length = $ - program_version_string
+ STRING 'RRQ Forth version 0.1 - 2021-05-13',10
WORD p_stdin,'STDIN',dovalue
;; Initialised to hold a STREAM for fd 0
dq 0
-
+
+;;; The main entry point.
+;;; This word is also the last word before syscalls
+last_forth_word:
WORD p_quit,'QUIT',fasm
;; QUIT is the program entry point ********************
main:
mov rsp,DS_TOP
mov rbp,RS_TOP
- ;; Initialize STREAM STDIN
+ cmp qword [p_stdin_DFA],0
+ jne p_quit_INITIALIZED
+ ;; Initialize STDIN
push 0
push 10000
DOFORTH p_stream
- pop qword [p_stdin_DFA]
+ pop qword [p_stdin_DFA] ; Assign STDIN
- ;; read a word
- push qword 1 ; ( fd ) =stdout
- push qword [p_stdin_DFA]
+p_quit_INITIALIZED:
+ ;; Initial blurb
FORTH
- dq p_read_word ; ( fd s n )
- dq sys_write
+ dq p_program_version
+ dq p_tell
+ dq p_stdin
+ dq p_clear_stream
+ dq p_stdin
+ dq p_evaluate_stream
+ BRANCH 0,p_quit_ERROR
+ dq p_false
+ dq sys_exit
+p_quit_ERROR:
+ dq p_literal_string
+ STRING 10,'*** Unknown word: '
+ dq p_tell
+ dq p_this_word
+ dq p_2get
+ dq p_tell
+ dq p_literal_string
+ STRING 10
+ dq p_tell
ENDFORTH
+ mov rbp,RS_TOP ; reset the return stack
+ jmp main
- push qword 1 ; stdout
- push qword program_version_string ; address of string
- push qword length ; length of string (cheating)
- DOFORTH sys_write ; printout
- pop rax ; ignore errors
-
- push 0
- DOFORTH sys_exit
+ ;; At fasm compilation: reset to make a new word list
+ previous_word = last_wordlists_word
- ;; TERMINATE0 terminates the program with code 0
- ;; ( v -- )
- WORD terminate, 'TERMINATE',fasm
- pop rdx
-terminate_special:
- mov eax,60
- syscall
+include 'syscalls.asm'
+
last_word:
- ;; FORTH is the last word of VOCABULARY FORTH
- WORD forth,'FORTH',dovalue
- dq forth_TFA
- dq 0
-
heap_start:
+ rb 1048576 ; +1 Mb heap
+ rb 1048576 ; +1 Mb heap
+ rb 1048576 ; +1 Mb heap
projects / rrq / rrqforth.git / blobdiff