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  56. <a name="Nios-II-Relocations"></a>
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  60. </div>
  61. <hr>
  62. <a name="Nios-II-Machine-Relocations"></a>
  63. <h4 class="subsection">9.31.3 Nios II Machine Relocations</h4>
  64. <a name="index-machine-relocations_002c-Nios-II"></a>
  65. <a name="index-Nios-II-machine-relocations"></a>
  66. <dl compact="compact">
  67. <dd><a name="index-hiadj-directive_002c-Nios-II"></a>
  68. </dd>
  69. <dt><code>%hiadj(<var>expression</var>)</code></dt>
  70. <dd><p>Extract the upper 16 bits of <var>expression</var> and add
  71. one if the 15th bit is set.
  72. </p>
  73. <p>The value of <code>%hiadj(<var>expression</var>)</code> is:
  74. </p><div class="smallexample">
  75. <pre class="smallexample">((<var>expression</var> &gt;&gt; 16) &amp; 0xffff) + ((<var>expression</var> &gt;&gt; 15) &amp; 0x01)
  76. </pre></div>
  77. <p>The <code>%hiadj</code> relocation is intended to be used with
  78. the <code>addi</code>, <code>ld</code> or <code>st</code> instructions
  79. along with a <code>%lo</code>, in order to load a 32-bit constant.
  80. </p>
  81. <div class="smallexample">
  82. <pre class="smallexample">movhi r2, %hiadj(symbol)
  83. addi r2, r2, %lo(symbol)
  84. </pre></div>
  85. <a name="index-hi-directive_002c-Nios-II"></a>
  86. </dd>
  87. <dt><code>%hi(<var>expression</var>)</code></dt>
  88. <dd><p>Extract the upper 16 bits of <var>expression</var>.
  89. </p>
  90. <a name="index-lo-directive_002c-Nios-II"></a>
  91. </dd>
  92. <dt><code>%lo(<var>expression</var>)</code></dt>
  93. <dd><p>Extract the lower 16 bits of <var>expression</var>.
  94. </p>
  95. <a name="index-gprel-directive_002c-Nios-II"></a>
  96. </dd>
  97. <dt><code>%gprel(<var>expression</var>)</code></dt>
  98. <dd><p>Subtract the value of the symbol <code>_gp</code> from
  99. <var>expression</var>.
  100. </p>
  101. <p>The intention of the <code>%gprel</code> relocation is
  102. to have a fast small area of memory which only
  103. takes a 16-bit immediate to access.
  104. </p>
  105. <div class="smallexample">
  106. <pre class="smallexample"> .section .sdata
  107. fastint:
  108. .int 123
  109. .section .text
  110. ldw r4, %gprel(fastint)(gp)
  111. </pre></div>
  112. <a name="index-call-directive_002c-Nios-II"></a>
  113. <a name="index-call_005flo-directive_002c-Nios-II"></a>
  114. <a name="index-call_005fhiadj-directive_002c-Nios-II"></a>
  115. <a name="index-got-directive_002c-Nios-II"></a>
  116. <a name="index-got_005flo-directive_002c-Nios-II"></a>
  117. <a name="index-got_005fhiadj-directive_002c-Nios-II"></a>
  118. <a name="index-gotoff-directive_002c-Nios-II"></a>
  119. <a name="index-gotoff_005flo-directive_002c-Nios-II"></a>
  120. <a name="index-gotoff_005fhiadj-directive_002c-Nios-II"></a>
  121. <a name="index-tls_005fgd-directive_002c-Nios-II"></a>
  122. <a name="index-tls_005fie-directive_002c-Nios-II"></a>
  123. <a name="index-tls_005fle-directive_002c-Nios-II"></a>
  124. <a name="index-tls_005fldm-directive_002c-Nios-II"></a>
  125. <a name="index-tls_005fldo-directive_002c-Nios-II"></a>
  126. </dd>
  127. <dt><code>%call(<var>expression</var>)</code></dt>
  128. <dt><code>%call_lo(<var>expression</var>)</code></dt>
  129. <dt><code>%call_hiadj(<var>expression</var>)</code></dt>
  130. <dt><code>%got(<var>expression</var>)</code></dt>
  131. <dt><code>%got_lo(<var>expression</var>)</code></dt>
  132. <dt><code>%got_hiadj(<var>expression</var>)</code></dt>
  133. <dt><code>%gotoff(<var>expression</var>)</code></dt>
  134. <dt><code>%gotoff_lo(<var>expression</var>)</code></dt>
  135. <dt><code>%gotoff_hiadj(<var>expression</var>)</code></dt>
  136. <dt><code>%tls_gd(<var>expression</var>)</code></dt>
  137. <dt><code>%tls_ie(<var>expression</var>)</code></dt>
  138. <dt><code>%tls_le(<var>expression</var>)</code></dt>
  139. <dt><code>%tls_ldm(<var>expression</var>)</code></dt>
  140. <dt><code>%tls_ldo(<var>expression</var>)</code></dt>
  141. <dd>
  142. <p>These relocations support the ABI for Linux Systems documented in the
  143. <cite>Nios II Processor Reference Handbook</cite>.
  144. </p></dd>
  145. </dl>
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