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Fix bug in like terms collection in expression simplification Like term collection would lose the actual "variable" part of the term if the second term collected happened to have no coefficient. This would cause the expression to take the value of the calculated coefficient which is obviously wrong. Thanks to hider <stego@satx.rr.com> for reporting the bug and providing a proper test case. Observation: this bug has been present since the first pre-release of lwtools 3.0 when the algebraic expression system was introduced. Apparently people tend not to create expressions that trigger the like terms handler. The specific conditions require the symbol to be undefined and the second operand to the addition has to have no coefficient so it's likely a fairly rare scenario. Still, it is somewhat surprising that nobody tripped on it before now.
author William Astle <lost@l-w.ca>
date Mon, 23 Jan 2017 22:58:36 -0700
parents fc166b3bbae3
children cad5937314cb
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>3.12. Cycle Counts</A
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>&#13;The following options for displaying cycle counts in listings are provided.
These options are enabled from pragmas on the command line or in the
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>opt c  - enable cycle counts: [8]
opt cd - enable detailed cycle counts breaking down addressing modes: [5+3]
opt ct - show a running subtotal of cycles
opt cc - clear the running subtotal</PRE
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>&#13;The assembler supports both 6809 as well as native-mode 6309 cycle counts.
In 6309 mode the counts are displayed in parenthesis instead of brackets. 
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>266f 7d25e2     (window.asm):00313 [7]     7       move   tst   putflg
2672 2602       (window.asm):00314 [5]     12             bne   a@
2674 1e13       (window.asm):00315 [8]     20             exg   x,u
2676 0dd6       (window.asm):00316 [6]     26      a@     tst   is6309
2678 2618       (window.asm):00317 [5]     31             bne   exit@
                (window.asm):00318                        opt   6309
267a 10860085   (window.asm):00319 (4)     35      b@     ldw   #133
267e 113813     (window.asm):00320 (6+?)   41             tfm   x+,u+
2681 30881b     (window.asm):00321 (4+1)   46             leax  27,x
2684 33c81b     (window.asm):00322 (4+1)   51             leau  27,u
2687 4a         (window.asm):00323 (1)     52             deca
2688 26f0       (window.asm):00324 (5)     57             bne   b@</PRE
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