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fix subtraction with relative values (relative-relative)=absolute!

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Phil Budne
2016-03-02 15:40:52 -05:00
parent 6791efe25c
commit f06f075517
1 changed files with 15 additions and 1 deletions
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16
tools/as7
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@@ -465,15 +465,29 @@ sub parse_expression {
if ($op eq '+') {
$word += $syllable;
$flags |= $sylflags;
}
elsif ($op eq '-') {
$word -= $syllable;
if ($flags & $RELATIVE) {
# relative-relative => absolute!
if ($sylflags & $RELATIVE) {
$flags &= ~$RELATIVE;
}
# else: relative-abs => relative (no change)
}
else { # word is absolute
if ($sylflags & $RELATIVE) {
err('A', 'absolute value minus relative??');
}
# else: absolute-absolute => absolute (no change)
}
}
else {
$word |= $syllable;
$flags |= $sylflags;
}
$word &= 0777777;
$flags |= $sylflags;
printf("\tsyllable: %#o word: %#o\n", $syllable, $word) if ($debug);
}
}