label#_entry:
dq initial_latest_entry
- dq 0
+ if immediate eq
+ db 0
+ else
+ db 1
+ end if
db .string_end - ($ + 1)
db name
.string_end:
;; entry.
forth_asm TCFA, '>CFA'
pop rax
- add rax, 16 ; [rax] = length of name
+ add rax, 8 + 1 ; [rax] = length of name
movzx rbx, byte [rax]
inc rax
add rax, rbx ; [rax] = codeword
;; Takes a string on the stack and replaces it with the decimal number that the
;; string represents.
forth_asm PARSE_NUMBER, 'PARSE-NUMBER'
- pop [parse_number.length] ; Length
- pop [parse_number.buffer] ; String pointer
+ pop rcx ; Length
+ pop rdi ; String pointer
push rsi
call parse_number
mov rdi, 0
syscall
-forth HELLO, 'HELLO'
- dq LIT, 'H', EMIT
- dq LIT, 'e', EMIT
- dq LIT, 'l', EMIT
- dq LIT, 'l', EMIT
- dq LIT, 'o', EMIT
- dq LIT, '!', EMIT
- dq NEWLINE
- dq EXIT
-
;; Duplicate a pair of elements.
forth_asm PAIRDUP, '2DUP'
pop rbx
add rsp, 8
next
+forth_asm NOT_, 'NOT'
+ pop rax
+ cmp rax, 0
+ jz .false
+.true:
+ push 0
+ next
+.false:
+ push 1
+ next
+
;; The INTERPRET word reads and interprets user input. It's behavior depends on
-;; the current STATE. It provides special handling for integers. (TODO)
+;; the current STATE. It provides special handling for integers.
forth INTERPRET, 'INTERPRET'
;; Read word
dq READ_WORD
;; Stack is (word length word length).
dq FIND ; Try to find word
dq DUP_
- dq ZBRANCH, 8 * 8 ; Check if word is found
+ dq ZBRANCH, 8 * 22 ; Check if word is found
- ;; Word is found, execute it
+ ;; - Word is found -
+
+ dq STATE, GET, ZBRANCH, 8 * 11 ; Check whether we are in compilation or immediate mode
+
+ ;; (Word found, compilation mode)
+ dq DUP_, IS_IMMEDIATE, NOT_, ZBRANCH, 8 * 6 ; If the word is immediate, continue as we would in immediate mode
+
+ ;; Otherwise, we want to compile this word
+ dq TCFA
+ dq COMMA
+ dq DROP, DROP
+ dq EXIT
+
+ ;; (Word found, immediate mode)
+ ;; Execute word
dq TCFA
;; Stack is (word length addr)
dq SWAP, DROP
dq EXEC
dq EXIT
- ;; No word is found, assume it is an integer literal
+ ;; - No word is found, assume it is an integer literal -
;; Stack is (word length addr)
dq DROP
dq PARSE_NUMBER
+
+ dq STATE, GET, ZBRANCH, 8 * 5 ; Check whether we are in compilation or immediate mode
+
+ ;; (Number, compilation mode)
+ dq LIT, LIT, COMMA
+ dq COMMA
+ dq EXIT
+
+ ;; (Number, immediate mode)
dq EXIT
;; .U prints the value on the stack as an unsigned integer in hexadecimal.
push rax
next
+forth_asm PUT_BYTE, 'C!'
+ pop rbx
+ pop rax ; Value
+ mov [rbx], al
+ next
+
+forth_asm GET_BYTE, 'C@'
+ pop rax
+ movzx rax, byte [rax]
+ push rax
+ next
+
;; Add two integers on the stack.
forth_asm PLUS, '+'
pop rax
push rbx
next
+;; Given two integers a and b on the stack, pushes the quotient and remainder of
+;; division of a by b.
+forth_asm TIMESMOD, '/MOD'
+ pop rbx ; b
+ pop rax ; a
+ mov rdx, 0
+ div rbx
+ push rax ; a / b
+ push rdx ; a % b
+ next
+
;; Get the location of the STATE variable. It can be set with '!' and read with
;; '@'.
forth STATE, 'STATE'
mov [latest_entry], rdi ; Update LATEST to point to this word
add rdi, 8
- mov rax, 0
- mov [rdi], rax ; Set immediate flag
+ mov [rdi], byte 0 ; Insert immediate flag
- add rdi, 8
- mov [rdi], rcx ; Insert length
+ add rdi, 1
+ mov [rdi], byte cl ; Insert length
;; Insert word string
add rdi, 1
dq LIT, 1
dq LATEST, GET
dq LIT, 8, PLUS
- dq PUT
+ dq PUT_BYTE
dq EXIT
-;; Return 0 if the given word is not immediate.
+;; Given the address of a word, return 0 if the given word is not immediate.
forth IS_IMMEDIATE, 'IMMEDIATE?'
- dq FIND
dq LIT, 8, PLUS
- dq GET
+ dq GET_BYTE
+ dq EXIT
+
+;; Enter immediate mode, immediately
+forth INTO_IMMEDIATE, '[', 1
+ dq LIT, 0, STATE, PUT_BYTE
+ dq EXIT
+
+;; Enter compilation mode
+forth OUTOF_IMMEDIATE, ']'
+ dq LIT, 1, STATE, PUT_BYTE
dq EXIT
+forth_asm TICK, "'"
+ lodsq
+ push rax
+ next
+
+forth_asm ROT, 'ROT'
+ pop rax
+ pop rbx
+ pop rdx
+ push rax
+ push rdx
+ push rbx
+ next
+
+forth_asm PICK, 'PICK'
+ pop rax
+ lea rax, [rsp + 8 * rax]
+ mov rax, [rax]
+ push rax
+ next
+
+forth_asm EQL, '='
+ pop rax
+ pop rbx
+ cmp rax, rbx
+ je .eq
+.noteq:
+ push 0
+ next
+.eq:
+ push 1
+ next
+
forth MAIN, 'MAIN'
- dq HELLO
dq INTERPRET
dq BRANCH, -8 * 2
dq TERMINATE
;; Reserve space for compiled words, accessed through HERE.
here dq here_top
-here_top rq $2000
+here_top rq $4000
;; Return stack
rq $2000
projects / rrq / jonasforth.git / blobdiff