diff options
Diffstat (limited to '04a/in03')
| -rw-r--r-- | 04a/in03 | 252 |
1 files changed, 250 insertions, 2 deletions
@@ -20,8 +20,182 @@ A=d3 syscall x2 J=A ?J<0:output_file_error -J=d0 -syscall x3c +; initialize :definitions_end +J=:definitions_end +D=:definitions +8J=D + +:read_line +; use rbp to store line pointer +R=:line +:read_line_loop + ; read 1 byte into rbp + J=d3 + I=R + D=d1 + syscall x0 + D=A + ?D=0:eof + + ; check if the character was a newline: + C=1R + D=xa + ?C=D:read_line_loop_end + R+=d1 + !:read_line_loop +:read_line_loop_end + +; check if line = "#define " up to a terminator of ' '. +C=x20 +I=:#define +J=:line +call :string= +D=A +?D!0:handle_#define + +; handle a normal line +; R will store a pointer to the current character +R=:line +:process_line_loop + C=1R + B=C + call :isident + ?A!0:process_ident + ; if *R is not an identifier character, just output it to the file. + J=d4 + B=C + call :fputc + ; check if we reached the end of the line + C=1R + D=xa + ?C=A:read_line + ; increment R, keep looping + R+=d1 + !:process_line_loop + :process_ident + ; if *R is an ident char. look up this identifier in :definitions. + ; use C to keep pointer to definition + C=:definitions + :lookup_loop + D=1C + ; check if we reached end of definition table + ?D=0:lookup_loop_end + ; check if this entry matches our identifier + I=R + J=C + call :ident= + ?A!0:perform_substitution + ; if not, skip over this entry + :skip_definition_loop + D=1C + I=xa + C+=d1 + ?I!D:skip_definition_loop + !:lookup_loop + :lookup_loop_end + ; this identifier doesn't match anything in the definitions table; just write it. + ; first, figure out how long it is + J=R + :length_loop + C=1J + B=C + call :isident + ?A=0:length_loop_end + J+=d1 + !:length_loop + :length_loop_end + ; now write it. + I=R + R=J + J-=I + D=J + J=d4 + syscall x1 + ; keep looping + !:process_line_loop + +:perform_substitution + ; right now, I is a pointer to the end of the identifier in :line, + ; and J is a pointer to the end of the identifier in :definitions. + + ; advance :line pointer for next loop iteration + R=I + + J+=d1 + ; J now points to the definition. let's write it + I=J + :definition_end_loop + C=1I + D=xa + ?C=D:definition_end_loop_end + I+=d1 + !:definition_end_loop + :definition_end_loop_end + D=I + D-=J + I=J + J=d4 + syscall x1 + ; process the rest of this line + !:process_line_loop + +:eof + J=d0 + syscall x3c + +; can the character in rbx appear in an identifier? +:isident + A='0 + ?B<A:return_0 + ; note: 58 = '9' + 1 + A=d58 + ?B<A:return_1 + A='A + ?B<A:return_0 + ; note: 91 = 'z' + 1 + A=d91 + ?B<A:return_1 + A='z + ?B>A:return_0 + ; 96 = 'a' - 1 + A=d96 + ?B>A:return_1 + A='_ + ?B=A:return_1 + !:return_0 + + +:handle_#define + J=:definitions_end + J=8J + ; start copy from after "#define" + I=:line + I+=d8 + + :#define_copy_loop + D=1I + 1J=D + I+=d1 + J+=d1 + A=xa + ?D=A:#define_copy_loop_end + !:#define_copy_loop + :#define_copy_loop_end + + ; update end of definitions + D=:definitions_end + 8D=J + ; emit newline so we don't screw up line numbers + J=d4 + I=:newline + D=d1 + syscall x1 + + !:read_line + +:newline + xa + :usage_error B=:usage_error_message @@ -72,3 +246,77 @@ syscall x3c I-=D A=I return + +:#define + str #define + x20 + x0 + +; check if strings in rdi and rsi are equal, up to terminator in rcx +:string= + D=1I + A=1J + ?D!A:return_0 + ?D=C:return_1 + I+=d1 + J+=d1 + !:string= + +; check if strings in rdi and rsi are equal, up to the first non-identifier character +:ident= + D=1I + B=D + call :isident + ; I ended + ?A=0:ident=_I_end + + D=1J + B=D + call :isident + ; J ended, but I didn't + ?A=0:return_0 + + ; we haven't reached the end of either + D=1I + A=1J + ?D!A:return_0 + I+=d1 + J+=d1 + !:ident= +:ident=_I_end + D=1J + B=D + call :isident + ; check if J also ended + ?A=0:return_1 + ; J didn't end + !:return_0 + +:return_0 + A=d0 + return +:return_1 + A=d1 + return + +; write the character in rbx to the file in rdi. +:fputc + C=B + I=S + I-=d1 + 1I=C + D=d1 + syscall x1 + return + + +align +:definitions_end + reserve d8 +:line + reserve d1000 +:definitions + reserve d200000 + +; we shouldn't end the file with a reserve; we don't handle that properly +x00 |