# some common helpers shared by phases of the SubX converter == code # instruction effective address register displacement immediate # . op subop mod rm32 base index scale r32 # . 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 # write an entire stream's contents to a buffered-file # ways to do this: # - construct a 'maximal slice' and pass it to write-slice-buffered # - flush the buffered-file and pass the stream directly to its fd (disabling buffering) # we'll go with the first way for now write-stream-data: # f : (address buffered-file), s : (address stream) -> # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # . save registers 50/push-EAX 51/push-ECX 56/push-ESI # ESI = s 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 0xc/disp8 . # copy *(EBP+12) to ESI # var slice/ECX = {s->data, s->data + s->write} # . push s->data + s->write 8b/copy 0/mod/indirect 6/rm32/ESI . . . 0/r32/EAX . . # copy *ESI to EAX 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/ESI 0/index/EAX . 0/r32/EAX 0xc/disp8 . # copy ESI+EAX+12 to EAX 50/push-EAX # . push s->data 8d/copy-address 1/mod/*+disp8 6/rm32/ESI . . . 0/r32/EAX 0xc/disp8 . # copy ESI+12 to EAX 50/push-EAX # . ECX = ESP 89/copy 3/mod/direct 1/rm32/ECX . . . 4/r32/ESP . . # copy ESP to ECX # write-slice-buffered(f, slice) # . . push args 51/push-ECX ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8) # . . call e8/call write-slice-buffered/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP $write-stream-data:end: # . restore locals 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # . restore registers 5e/pop-to-ESI 59/pop-to-ECX 58/pop-to-EAX # . epilog 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP 5d/pop-to-EBP c3/return test-write-stream-data: # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # setup # . clear-stream(_test-output-stream) # . . push args 68/push _test-output-stream/imm32 # . . call e8/call clear-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . clear-stream(_test-output-buffered-file+4) # . . push args b8/copy-to-EAX _test-output-buffered-file/imm32 05/add-to-EAX 4/imm32 50/push-EAX # . . call e8/call clear-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . clear-stream(_test-input-stream) # . . push args 68/push _test-input-stream/imm32 # . . call e8/call clear-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # initialize input # . write(_test-input-stream, "abcd") # . . push args 68/push "abcd"/imm32 68/push _test-input-stream/imm32 # . . call e8/call write/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # write-stream-data(_test-output-buffered-file, _test-input-stream) # . . push args 68/push _test-input-stream/imm32 68/push _test-output-buffered-file/imm32 # . . call e8/call write-stream-data/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # check that the write happened as expected # . flush(_test-output-buffered-file) # . . push args 68/push _test-output-buffered-file/imm32 # . . call e8/call flush/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . check-stream-equal(_test-output-stream, "abcd", msg) # . . push args 68/push "F - test-write-stream-data"/imm32 68/push "abcd"/imm32 68/push _test-output-stream/imm32 # . . call e8/call check-stream-equal/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP # . epilog 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP 5d/pop-to-EBP c3/return == data _test-input-stream: # current write index 0/imm32 # current read index 0/imm32 # length 0x100/imm32 # 256 bytes # data (16 lines x 16 bytes/line) 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 # a test buffered file for _test-input-stream _test-input-buffered-file: # file descriptor or (address stream) _test-input-stream/imm32 # current write index 0/imm32 # current read index 0/imm32 # length 6/imm32 # data 00 00 00 00 00 00 # 6 bytes _test-output-stream: # current write index 0/imm32 # current read index 0/imm32 # length 0x100/imm32 # 256 bytes # data (16 lines x 16 bytes/line) 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 # a test buffered file for _test-output-stream _test-output-buffered-file: # file descriptor or (address stream) _test-output-stream/imm32 # current write index 0/imm32 # current read index 0/imm32 # length 6/imm32 # data 00 00 00 00 00 00 # 6 bytes # . . vim:nowrap:textwidth=0