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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 |
children |
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Symbols</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="LW Tool Chain" HREF="index.html"><LINK REL="UP" TITLE="LWASM" HREF="c45.html"><LINK REL="PREVIOUS" TITLE="Source Format" HREF="x177.html"><LINK REL="NEXT" TITLE="Numbers and Expressions" HREF="x192.html"></HEAD ><BODY CLASS="SECTION" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >LW Tool Chain</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="x177.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 3. LWASM</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="x192.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECTION" ><H1 CLASS="SECTION" ><A NAME="AEN187" >3.4. Symbols</A ></H1 ><P >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 ><P >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 ><P >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 ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="x177.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="x192.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Source Format</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="c45.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Numbers and Expressions</TD ></TR ></TABLE ></DIV ></BODY ></HTML >