view docs/manual/x827.html @ 583:000381ee2d5c default tip

Guard against single operand multiplication when detecting like terms This *shouldn't* happen, but it apparently does in some pathological cases so guard against a single operand multiplication to prevent a crash.
author William Astle <lost@l-w.ca>
date Mon, 04 Nov 2024 23:48:23 -0700
parents fc072f6cde09
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>3.11. Convenience Instructions</A
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>&#13;Similar to the 6800 compatibility instructions (pragma 6800compat) these
pragma 6809conv and pragma 6309conv enable convenience extensions to the
6809 and 6309 instruction set.  Originally intended for compatibility with
the MACRO-80c assembler, these have proven useful in large codebases that
target both the 6809 and the 6309.</P
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>&#13;The 6809 extensions are straightforward with the exception of "TSTD" which
assembles as "STD -2,S".  A benefit of using these is they will "just work"
and take on their 6309 equivalent when you enable 6309 assembly mode. 
Supported instructions: ASRD, CLRD,   COMD,   LSLD,   LSRD,   NEGD,   TSTD.</P
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>&#13;6309 extensions are based on common patterns described by Chris Burke and
Darren Atkinson in their 6309 documentation and include the following
instructions: ASRQ,   CLRQ,   COMQ,   LSLE,   LSLF,   LSLQ,   LSRQ,   NEGE,
   NEGF,   NEGW,   NEGQ,   TSTQ.</P
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