mu - Soul of a tiny new machine. More thorough tests → More comprehensible and rewrite-friendly software → More resilient society.

	Commit message (Expand)	Author	Age	Files	Lines
*	.	Kartik Agaram	2021-04-21	1	-4/+4
*	.	Kartik Agaram	2021-03-23	1	-0/+226

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Mu - linux/ex5.subx</title> <meta name="Generator" content="Vim/8.1"> <meta name="plugin-version" content="vim8.1_v1"> <meta name="syntax" content="none"> <meta name="settings" content="number_lines,use_css,no_foldcolumn,expand_tabs,line_ids,prevent_copy="> <meta name="colorscheme" content="minimal-dark"> <style type="text/css">  </style> <script type='text/javascript'>  </script> </head> <body onload='JumpToLine();'> <a href='https://github.com/akkartik/mu/blob/main/linux/ex5.subx'>https://github.com/akkartik/mu/blob/main/linux/ex5.subx</a> <pre id='vimCodeElement'> 1 # Read a character from stdin, save it to a local on the stack, write it to stdout. 2 # 3 # To run: 4 # $ bootstrap/bootstrap translate ex5.subx -o ex5 5 # $ bootstrap/bootstrap run ex5 6 7 == code 8 # instruction effective address register displacement immediate 9 # . op subop mod rm32 base index scale r32 10 # . 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes 11 12 Entry: 13 14 # allocate x on the stack 15 81 5/subop/subtract 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # subtract from esp 16 17 # read(stdin, x, 1) 18 # . fd = 0 (stdin) 19 bb/copy-to-ebx 0/imm32 20 # . data = x (location to write result to) 21 8d/copy-address 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none 1/r32/ecx 4/disp8 . # copy esp+4 to ecx 22 # . size = 1 character 23 ba/copy-to-edx 1/imm32 24 # . syscall 25 e8/call <a href='000init.subx.html#L23'>syscall_read</a>/disp32 26 27 # syscall(write, stdout, x, 1) 28 # . fd = 1 (stdout) 29 bb/copy-to-ebx 1/imm32 30 # . data = x (location to read from) 31 8d/copy-address 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none 1/r32/ecx 4/disp8 . # copy esp+4 to ecx 32 # . size = 1 character 33 ba/copy-to-edx 1/imm32 34 # . syscall 35 e8/call <a href='000init.subx.html#L29'>syscall_write</a>/disp32 36 37 # exit(ebx) 38 e8/call <a href='000init.subx.html#L18'>syscall_exit</a>/disp32 39 40 # . . vim:nowrap:textwidth=0 </pre> </body> </html>