vacca@burdvax.UUCP (04/18/84)
I am trying to determine the percentage of users (in the following
three environments) who actually use assembler to some degree:
1. UNIX systems programmers
2. UNIX applications programmers
3. students and faculty in a university UNIX environment
The question is whether or not C is a viable alternative to using assembler.
It seems that the SysV manuals are trying to dissuade UNIX programmers from
using assembler. Is this true?rej@cornell.UUCP (04/19/84)
C can replace assembler. The only use for assembler on VAXen is to write the context switching routines and to improve the speed of a few commonly used subroutines. People that I know programming in C on a 68000 never seem to use assembler. The Cornell Program Synthesiser is written in C and runs on many PDP-11s across campus. Its device drivers and overlay routines are written in C, with only the process switching routines being in assembler. Ralph Johnson cornell!rej
laman@sdcsvax.UUCP (04/21/84)
Also used in the C library for the system interface routines, but that's
not the kernel...
Nooooo.... Not ANOTHER set of interface routines.....
Mike Laman
UUCP: {ucbvax,philabs,sdccsu3,sdcsla}!sdcsvax!lamangwyn@BRL-VLD.ARPA (04/25/84)
From: Doug Gwyn (VLD/VMB) <gwyn@BRL-VLD.ARPA> About the only use of assembler on our many UNIX systems is by kernel workers or C run-time library maintainers in direct support of the software used by everybody else. If the UNIX System V manuals appear to dissuade programmers from using assembler, then that is a good sign. The ONLY times I resort to assembler rather than C are: -- function cannot be performed in C. There are very few cases where this is true; implementing setjmp/longjmp is a good example. -- C implementation is a bottleneck. One identifies such cases by profiling the code, then considering whether the improved speed is going to be worth the maintenance costs associated with use of assembler. Seldom is it really worthwhile to use assembler, all things considered.