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Update to gcc6809lw patch which may help compilation of some sources
Due to persistent random compiler crashes and errors related to "M_REGS",
this patch update (4.6.4-2) essentially removes the varius constraints
allowing the "soft registers" in most operations. It was causing more
problems than it solved and it is not clear that the logic behind those soft
registers even makes sense any more.
This patch also fixes a bogus comparison related to selecting the right size
for a constant. Instead of the excessively clever comparison scheme that was
previously in use, the comparisons have been replaced with straight forward
comparisions for the top and bottom of the relevant 2's complement ranges.
author | William Astle <lost@l-w.ca> |
---|---|
date | Mon, 20 Jul 2015 22:32:41 -0600 |
parents | fc166b3bbae3 |
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="c62.html"><LINK REL="PREVIOUS" TITLE="Source Format" HREF="x227.html"><LINK REL="NEXT" TITLE="Numbers and Expressions" HREF="x242.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="x227.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="x242.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECTION" ><H1 CLASS="SECTION" ><A NAME="AEN237" >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="x227.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="x242.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="c62.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Numbers and Expressions</TD ></TR ></TABLE ></DIV ></BODY ></HTML >