From: Jonas Hvid Date: Sun, 8 Mar 2020 14:27:49 +0000 (+0100) Subject: Embed sys.f into binary and start working on POP-WORD X-Git-Url: https://git.rrq.au/?a=commitdiff_plain;h=fbd07fa0c1aaad0cca46f9b1fc4839e053454f03;p=rrq%2Fjonasforth.git Embed sys.f into binary and start working on POP-WORD --- diff --git a/Makefile b/Makefile index 1bfaabe..cb7bff3 100644 --- a/Makefile +++ b/Makefile @@ -2,7 +2,7 @@ run: main cat sys.f - | ./main -main: main.asm impl.asm bootstrap.asm +main: main.asm impl.asm bootstrap.asm sys.f fasm $< $@ .PHONY: clean diff --git a/example.f b/example.f index 41993d7..547887f 100644 --- a/example.f +++ b/example.f @@ -25,4 +25,9 @@ S" 10 FIB = " TELL 10 FIB .U SPACE S" (Expected: 59)" TELL NEWLINE +S" Word:" TELL NEWLINE +SYSCODE POP-WORD TELL NEWLINE +S" Remaining:" TELL NEWLINE +TELL + TERMINATE diff --git a/impl.asm b/impl.asm index a9b8564..c713036 100644 --- a/impl.asm +++ b/impl.asm @@ -129,6 +129,27 @@ read_word: ret +;; Read a word from a buffer. Returns the buffer without the word, as well as +;; the word that was read (including lengths). +;; +;; Inputs: +;; * rsi = Input buffer +;; * rcx = Length of buffer +;; +;; Outputs: +;; * rsi = Updated buffer +;; * rcx = Length of updated buffer +;; * rdi = Word buffer +;; * rdx = Length of word buffer +pop_word: + mov rdi, rsi + mov rdx, 10 + + add rsi, 10 + sub rcx, 10 + + ret + ;; Parses a string. ;; ;; Parameters: diff --git a/main.asm b/main.asm index 538039b..c9a7fc4 100644 --- a/main.asm +++ b/main.asm @@ -207,6 +207,25 @@ forth_asm READ_WORD, 'READ-WORD' mov rsi, [.rsi] next +;; Read a word from a buffer. Expects (buffer buffer-length) on the stack. +;; Updates buffer and buffer-length, such that the word has been removed from +;; the buffer. Appends (word-buffer word-buffer-length) to the stack. +forth_asm POP_WORD, 'POP-WORD' + pushr rsi + + pop rcx ; Length + pop rsi ; Buffer + + call pop_word + + push rsi ; Updated buffer + push rcx ; Length of updated buffer + push rdi ; Word buffer + push rdx ; Length of word buffer + + popr rsi + next + ;; Takes a string on the stack and replaces it with the decimal number that the ;; string represents. forth_asm PARSE_NUMBER, 'PARSE-NUMBER' @@ -505,6 +524,11 @@ forth HERE, 'HERE' dq LIT, here dq EXIT +forth SYSCODE, 'SYSCODE' + dq LIT, sysf + dq LIT, sysf.len + dq EXIT + segment readable writable ;; The LATEST variable holds a pointer to the word that was last added to the @@ -538,3 +562,12 @@ here_top rq $4000 ;; Return stack rq $2000 return_stack_top: + +segment readable + +;; We store some Forth code in sys.f that defined common words that the user +;; would expect to have available at startup. To execute these words, we just +;; include the file directly in the binary, and then interpret it at startup. +sysf file 'sys.f' +sysf.len = $ - sysf +