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Fix internal compiler error on "var2 = var1 + 1" patterns This appears to be the correct fix. It was provided by Tormod Volden (debian.tormod@gmail.com). The final commit is substantially different from Tormod's submission mostly due to housecleaning (removing the old patches and updating the README). Tormod's comments follow. The original addhi_mem_1 "insn" instruction pattern /matches/ two memory operands, just with the /constraint/ that these are the same location. A pattern match tells the compiler "you should be able to use this, but you might have to work on it to meet the constraints". For typical constraints on registers the compiler can add "reloads", moving stuff between registers or from memory, until the constraints are met and the instruction can be used. However, in this case, no amount of reloads can make two memory locations the same if they already weren't, so the compiler breaks down and cries "unable to generate reloads". It seems this issue only appears if optimization is enabled. The proof is in gcc's reload.c and is left as an exercise to the reader. Limiting the matching pattern to identical memory operands avoids these situations, while allowing the common "var++" cases. References: The pattern/constraints difference is explained in https://gcc.gnu.org/onlinedocs/gccint/Simple-Constraints.html#index-other-register-constraints-3335
author William Astle <lost@l-w.ca>
date Tue, 29 Mar 2016 21:21:49 -0600
parents e95f07cbce4e
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>2.4. Motorola S-Record</A
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>This ASCII format consists of a series of CR+LF terminated "records" of ASCII
text. Each record has the following structure: a start-of-record character
"S", an ASCII record type digit (0-9), a two-digit ASCII hex byte count, a 
four-digit ASCII hex address, an optional sequence of two-digit ASCII hex data
values, and a two-digit ASCII hex checksum. The LW tool chain issues only S0, 
S1, S5 and S9 record types. S1 records are limited to maximum of 16 data bytes
in length, and  paragraph alignment of addresses is favored. The address
sequence of the S-Records directly follows that of the source file; multiple
ORG directives in the source code may result in out-of-sequence addresses in
the S-Record output. </P
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>Motorola S-Record format is a standard ASCII format accepted by most memory
device programming equipment. It is particularly useful when the assembled 
code output is destined to reside within an EPROM or Flash memory device,
for example.</P
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>LWASM can output this format since version 4.10. LWLINK can output this format
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