[Bug gas/24982] New: m68k tdiv instructions assembled incorrectly

[miod at online dot fr]

https://sourceware.org/bugzilla/show_bug.cgi?id=24982

            Bug ID: 24982
           Summary: m68k tdiv instructions assembled incorrectly
           Product: binutils
           Version: 2.33 (HEAD)
            Status: UNCONFIRMED
          Severity: minor
          Priority: P2
         Component: gas
          Assignee: unassigned at sourceware dot org
          Reporter: miod at online dot fr
  Target Milestone: ---

Created attachment 11982
  --> https://sourceware.org/bugzilla/attachment.cgi?id=11982&action=edit
m68k-opc.c patch

Motorola SVR4 as uses "tdiv" as an alias for a 32-bit divide operator (32-bit
operand, 32-bit divider, get 32-bit remainder and quotient). In other words,
"tdivs" is a synonym of "divsll" and "tdivu" of "divull".

However, the current translation in opc-m68k.c translates them to "divsl" and
"divul", which are the 64-bit operand, 32-bit divider, flavour. This
translation has been incorrect since at least 1995 since it is already
incorrect in the sourceware CVS import. Of course, the poor choice of mnemonics
(div{s,u}l being 32/32 and div{s,u} being 64/32) probably led to that error.

This probably went unnoticed because not much code, outside of Motorola's own
code, has been written using the "tdiv" mnemonics; and such code was fed to
Motorola's as which does not suffer from that bug.

Trivial diff attached.

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