view docs/manual/x227.html @ 416:b4d0eafc5bfe

Fix code generation error in gcc6809 It turned out that under some circumstances, the gcc optimizer would select an instruction sequence that had the sense of a branch inverted. It seems this was due to a particular instruction pattern included in the machine description not being quite right with respect to how the condition codes were tracked. Removing that instruction pattern seems to fix things (subtraction with the arguments reversed). gcc seems to be smart enough to figure out how to reorganize code to work without this reversed sense subtraction and then do the right thing.
author William Astle <lost@l-w.ca>
date Thu, 24 Mar 2016 20:07:20 -0600
parents fc166b3bbae3
children
line wrap: on
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>3.3. Source Format</A
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>LWASM accepts plain text files in a relatively free form. It can handle
lines terminated with CR, LF, CRLF, or LFCR which means it should be able
to assemble files on any platform on which it compiles.</P
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>Each line may start with a symbol. If a symbol is present, there must not
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>The op code is separated from the symbol by whitespace. If there is
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> It is important to note that operands cannot contain any whitespace
except in the case of delimited strings.  This is because the first
whitespace character will be interpreted as the separator between the
operand column and the comment.  This behaviour is required for approximate
source compatibility with other 6x09 assemblers.  </P
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>A comment can also be introduced with a * or a ;. The comment character is
optional for end of statement comments. However, if a symbol is the only
thing present on the line other than the comment, the comment character is
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>The opcode is not treated case sensitively. Neither are register names in
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> As of version 2.6, LWASM supports files with line numbers.  If line
numbers are present, the line must start with a digit.  The line number
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