view docs/manual/x827.html @ 577:e49d24f4a9a5

Correct bug in the object file output code leading to stack corruption It turns out leaving a pointer to a stack allocated temporary in a persistent data structure is not conducive to correct program operation. Undo the export check setup in the object file output sequence so a pointer to stack allocated memory is not left hanging when the function returns. This seems to correct at least one mysterious crash bug, and possibly others. Thanks to Boisy Pitre for reporting the crash bug that led to this discovery, as well as a previous crash bug that likely has the same root cause. Additional thanks to Ciaran Anscomb whose debugger wielding wizardry revealed the exact location of this particular bit of unbrilliance.
author William Astle <lost@l-w.ca>
date Sat, 03 Aug 2024 14:30:06 -0600
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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