view docs/manual/x187.html @ 241:d0e9dbe9afbe

Add new heuristic for resolving instruction sizes. Add new heuristic for resolving instruction sizes. This applies to the the decision between extended and base page addressing by calculating the range of possible addresses (if reasonably knowable) and deciding on whether to force extended addressing based on that. (If the whole range is outside the direct page, extended addressing is required.)
author William Astle <lost@l-w.ca>
date Sun, 23 Sep 2012 13:06:43 -0600
parents 2cc599f1bebf
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>3.4. Symbols</A
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>Symbols have no length restriction. They may contain letters, numbers, dots,
dollar signs, and underscores. They must start with a letter, dot, or
underscore.</P
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>LWASM also supports the concept of a local symbol. A local symbol is one
which contains either a "?" or a "@", which can appear anywhere in the symbol.
The scope of a local symbol is determined by a number of factors. First,
each included file gets its own local symbol scope. A blank line will also
be considered a local scope barrier. Macros each have their own local symbol
scope as well (which has a side effect that you cannot use a local symbol
as an argument to a macro). There are other factors as well. In general,
a local symbol is restricted to the block of code it is defined within.</P
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>By default, unless assembling to the os9 target, a "$" in the symbol will
also make it local.  This can be controlled by the "dollarlocal" and
"nodollarlocal" pragmas.  In the absence of a pragma to the contrary, for
the os9 target, a "$" in the symbol will not make it considered local while
for all other targets it will.</P
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