From: Jonas Hvid Date: Thu, 21 Nov 2019 17:23:14 +0000 (+0100) Subject: Change indentation to use 2 spaces X-Git-Url: https://git.rrq.au/?a=commitdiff_plain;h=8d5c5f5affc85bae309c04f096b65a87c2f33cb6;p=rrq%2Fjonasforth.git Change indentation to use 2 spaces --- diff --git a/main.asm b/main.asm index c6ada73..0a8ff4c 100644 --- a/main.asm +++ b/main.asm @@ -4,33 +4,33 @@ format ELF64 executable ;; executing a definition, this code is what causes execution to resume at the ;; next word in that definition. macro next { - ;; RSI points to the address of the definition of the next word to execute. - lodsq ; Load value at RSI into RAX and increment RSI - ;; Now RAX contains the location of the next word to execute. The first 8 - ;; bytes of this word is the address of the codeword, which is what we want - ;; to execute. - jmp qword [rax] ; Jump to the codeword of the current word + ;; RSI points to the address of the definition of the next word to execute. + lodsq ; Load value at RSI into RAX and increment RSI + ;; Now RAX contains the location of the next word to execute. The first 8 + ;; bytes of this word is the address of the codeword, which is what we want + ;; to execute. + jmp qword [rax] ; Jump to the codeword of the current word } ;; pushr and popr work on the return stack, whose location is stored in the ;; register RBP. macro pushr x { - sub rbp, 8 - mov qword [rbp], x + sub rbp, 8 + mov qword [rbp], x } macro popr x { - mov x, [rbp] - add rbp, 8 + mov x, [rbp] + add rbp, 8 } segment readable executable main: - cld ; Clear direction flag so LODSQ does the right thing. - mov rbp, return_stack_top ; Initialize return stack + cld ; Clear direction flag so LODSQ does the right thing. + mov rbp, return_stack_top ; Initialize return stack - mov rsi, program - next + mov rsi, program + next program: dq MAIN @@ -38,68 +38,68 @@ program: dq MAIN ;; word. It needs to save the old RSI and update it to point to the next word to ;; execute. docol: - pushr rsi ; Save old value of RSI on return stack; we will continue execution there after we are done executing this word - lea rsi, [rax + 8] ; RAX currently points to the address of the codeword, so we want to continue at RAX+8 - next ; Execute word pointed to by RSI + pushr rsi ; Save old value of RSI on return stack; we will continue execution there after we are done executing this word + lea rsi, [rax + 8] ; RAX currently points to the address of the codeword, so we want to continue at RAX+8 + next ; Execute word pointed to by RSI ;; This word is called at the end of a Forth definition. It just needs to ;; restore the old value of RSI (saved by 'docol') and resume execution. EXIT: - dq .start + dq .start .start: - popr rsi - next + popr rsi + next EMIT: - dq .start + dq .start .start: - pushr rsi - pushr rax - mov rax, 1 - mov rdi, 1 - lea rsi, [rsp] - mov rdx, 1 - syscall - add rsp, 8 - popr rax - popr rsi - next + pushr rsi + pushr rax + mov rax, 1 + mov rdi, 1 + lea rsi, [rsp] + mov rdx, 1 + syscall + add rsp, 8 + popr rax + popr rsi + next PUSH_HELLO_CHARS: - dq .start -.start: - push $A - push 'o' - push 'l' - push 'l' - push 'e' - push 'H' - next + dq .start + .start: + push $A + push 'o' + push 'l' + push 'l' + push 'e' + push 'H' + next HELLO: - dq docol - dq PUSH_HELLO_CHARS - dq EMIT - dq EMIT - dq EMIT - dq EMIT - dq EMIT - dq EMIT - dq EXIT + dq docol + dq PUSH_HELLO_CHARS + dq EMIT + dq EMIT + dq EMIT + dq EMIT + dq EMIT + dq EMIT + dq EXIT TERMINATE: - dq .start -.start: - mov rax, $3C - mov rdi, 0 - syscall + dq .start + .start: + mov rax, $3C + mov rdi, 0 + syscall MAIN: - dq docol - dq HELLO - dq HELLO - dq HELLO - dq TERMINATE + dq docol + dq HELLO + dq HELLO + dq HELLO + dq TERMINATE segment readable writable