[TUHS] Design of the AT&T assembly syntax

Some time ago, I wrote a piece [1] about the design of the AT&T assembler syntax. While I'm still not quite sure if everything in there is correct, this explanation seemed plausible to me; the PDP-11 assembler being adapted for the 8086, then the 80386 and then ELF targets, giving us today's convoluted syntax. The one thing in this chain I have never found is an AT&T style assembler for x86 before ELF was introduced. Supposedly, it would get away without % as a register prefix, thus being much less obnoxious to use. Any idea if such an assembler ever existed and if yes where? I suppose Xenix might have shipped something like that. The only AT&T syntax assemblers I know today are those from Solaris, the GNU project, the LLVM project, and possibly whatever macOS ships. Are there (or where there) any other x86 AT&T assemblers? Who was the first party to introduce this? Yours, Robert Clausecker [1]: https://stackoverflow.com/a/42250270/417501 -- () ascii ribbon campaign - for an 8-bit clean world /\ - against html email - against proprietary attachments