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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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1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
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2 <HTML
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3 ><HEAD
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4 ><TITLE
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5 >Symbols</TITLE
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6 ><META
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7 NAME="GENERATOR"
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8 CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
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9 REL="HOME"
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10 TITLE="LW Tool Chain"
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11 HREF="index.html"><LINK
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12 REL="UP"
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13 TITLE="LWASM"
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14 HREF="c62.html"><LINK
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15 REL="PREVIOUS"
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16 TITLE="Source Format"
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17 HREF="x227.html"><LINK
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18 REL="NEXT"
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19 TITLE="Numbers and Expressions"
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20 HREF="x242.html"></HEAD
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21 ><BODY
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22 CLASS="SECTION"
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23 BGCOLOR="#FFFFFF"
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24 TEXT="#000000"
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25 LINK="#0000FF"
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26 VLINK="#840084"
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27 ALINK="#0000FF"
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28 ><DIV
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29 CLASS="NAVHEADER"
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30 ><TABLE
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31 SUMMARY="Header navigation table"
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32 WIDTH="100%"
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33 BORDER="0"
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34 CELLPADDING="0"
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35 CELLSPACING="0"
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36 ><TR
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37 ><TH
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38 COLSPAN="3"
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39 ALIGN="center"
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40 >LW Tool Chain</TH
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41 ></TR
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42 ><TR
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43 ><TD
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44 WIDTH="10%"
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45 ALIGN="left"
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46 VALIGN="bottom"
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47 ><A
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48 HREF="x227.html"
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49 ACCESSKEY="P"
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50 >Prev</A
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51 ></TD
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52 ><TD
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53 WIDTH="80%"
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54 ALIGN="center"
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55 VALIGN="bottom"
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56 >Chapter 3. LWASM</TD
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57 ><TD
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58 WIDTH="10%"
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59 ALIGN="right"
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60 VALIGN="bottom"
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61 ><A
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62 HREF="x242.html"
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63 ACCESSKEY="N"
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64 >Next</A
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65 ></TD
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66 ></TR
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67 ></TABLE
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68 ><HR
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69 ALIGN="LEFT"
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70 WIDTH="100%"></DIV
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71 ><DIV
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72 CLASS="SECTION"
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73 ><H1
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74 CLASS="SECTION"
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75 ><A
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76 NAME="AEN237"
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77 >3.4. Symbols</A
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78 ></H1
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79 ><P
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80 >Symbols have no length restriction. They may contain letters, numbers, dots,
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81 dollar signs, and underscores. They must start with a letter, dot, or
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82 underscore.</P
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83 ><P
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84 >LWASM also supports the concept of a local symbol. A local symbol is one
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85 which contains either a "?" or a "@", which can appear anywhere in the symbol.
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86 The scope of a local symbol is determined by a number of factors. First,
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87 each included file gets its own local symbol scope. A blank line will also
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88 be considered a local scope barrier. Macros each have their own local symbol
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89 scope as well (which has a side effect that you cannot use a local symbol
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90 as an argument to a macro). There are other factors as well. In general,
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91 a local symbol is restricted to the block of code it is defined within.</P
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92 ><P
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93 >By default, unless assembling to the os9 target, a "$" in the symbol will
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94 also make it local. This can be controlled by the "dollarlocal" and
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95 "nodollarlocal" pragmas. In the absence of a pragma to the contrary, for
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96 the os9 target, a "$" in the symbol will not make it considered local while
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97 for all other targets it will.</P
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98 ></DIV
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99 ><DIV
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100 CLASS="NAVFOOTER"
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101 ><HR
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102 ALIGN="LEFT"
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103 WIDTH="100%"><TABLE
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104 SUMMARY="Footer navigation table"
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105 WIDTH="100%"
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106 BORDER="0"
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107 CELLPADDING="0"
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108 CELLSPACING="0"
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109 ><TR
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110 ><TD
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111 WIDTH="33%"
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112 ALIGN="left"
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113 VALIGN="top"
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114 ><A
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115 HREF="x227.html"
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116 ACCESSKEY="P"
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117 >Prev</A
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118 ></TD
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119 ><TD
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120 WIDTH="34%"
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121 ALIGN="center"
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122 VALIGN="top"
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123 ><A
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William Astle <lost@l-w.ca>
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124 HREF="index.html"
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125 ACCESSKEY="H"
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126 >Home</A
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127 ></TD
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128 ><TD
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129 WIDTH="33%"
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130 ALIGN="right"
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131 VALIGN="top"
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132 ><A
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133 HREF="x242.html"
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134 ACCESSKEY="N"
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135 >Next</A
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136 ></TD
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137 ></TR
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138 ><TR
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139 ><TD
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140 WIDTH="33%"
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141 ALIGN="left"
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142 VALIGN="top"
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143 >Source Format</TD
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144 ><TD
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145 WIDTH="34%"
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146 ALIGN="center"
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147 VALIGN="top"
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William Astle <lost@l-w.ca>
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148 ><A
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William Astle <lost@l-w.ca>
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149 HREF="c62.html"
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William Astle <lost@l-w.ca>
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150 ACCESSKEY="U"
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William Astle <lost@l-w.ca>
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151 >Up</A
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William Astle <lost@l-w.ca>
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152 ></TD
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William Astle <lost@l-w.ca>
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153 ><TD
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154 WIDTH="33%"
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William Astle <lost@l-w.ca>
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155 ALIGN="right"
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156 VALIGN="top"
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157 >Numbers and Expressions</TD
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158 ></TR
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159 ></TABLE
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160 ></DIV
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William Astle <lost@l-w.ca>
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161 ></BODY
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162 ></HTML
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163 >