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101 lines
3.7 KiB
HTML
101 lines
3.7 KiB
HTML
4 years ago
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<title>LM32-Modifiers - Using as</title>
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="up" href="LM32-Syntax.html#LM32-Syntax" title="LM32 Syntax">
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<link rel="prev" href="LM32_002dRegs.html#LM32_002dRegs" title="LM32-Regs">
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<!--
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This file documents the GNU Assembler "as".
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Copyright (C) 1991-2015 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3
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or any later version published by the Free Software Foundation;
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with no Invariant Sections, with no Front-Cover Texts, and with no
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Back-Cover Texts. A copy of the license is included in the
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</head>
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<body>
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<div class="node">
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<a name="LM32-Modifiers"></a>
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<a name="LM32_002dModifiers"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="LM32_002dChars.html#LM32_002dChars">LM32-Chars</a>,
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Previous: <a rel="previous" accesskey="p" href="LM32_002dRegs.html#LM32_002dRegs">LM32-Regs</a>,
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Up: <a rel="up" accesskey="u" href="LM32-Syntax.html#LM32-Syntax">LM32 Syntax</a>
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<hr>
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</div>
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<h5 class="subsubsection">9.20.2.2 Relocatable Expression Modifiers</h5>
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<p><a name="index-LM32-modifiers-1254"></a><a name="index-syntax_002c-LM32-1255"></a>
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The assembler supports several modifiers when using relocatable addresses
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in LM32 instruction operands. The general syntax is the following:
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<pre class="smallexample"> modifier(relocatable-expression)
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</pre>
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<a name="index-symbol-modifiers-1256"></a>
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<dl>
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<dt><code>lo</code><dd>
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This modifier allows you to use bits 0 through 15 of
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an address expression as 16 bit relocatable expression.
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<br><dt><code>hi</code><dd>
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This modifier allows you to use bits 16 through 23 of an address expression
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as 16 bit relocatable expression.
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<p>For example
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<pre class="smallexample"> ori r4, r4, lo(sym+10)
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orhi r4, r4, hi(sym+10)
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</pre>
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<br><dt><code>gp</code><dd>
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This modified creates a 16-bit relocatable expression that is
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the offset of the symbol from the global pointer.
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<pre class="smallexample"> mva r4, gp(sym)
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</pre>
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<br><dt><code>got</code><dd>
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This modifier places a symbol in the GOT and creates a 16-bit
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relocatable expression that is the offset into the GOT of this
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symbol.
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<pre class="smallexample"> lw r4, (gp+got(sym))
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</pre>
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<br><dt><code>gotofflo16</code><dd>
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This modifier allows you to use the bits 0 through 15 of an
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address which is an offset from the GOT.
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<br><dt><code>gotoffhi16</code><dd>
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This modifier allows you to use the bits 16 through 31 of an
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address which is an offset from the GOT.
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<pre class="smallexample"> orhi r4, r4, gotoffhi16(lsym)
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addi r4, r4, gotofflo16(lsym)
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</pre>
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</dl>
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</body></html>
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