89 lines
3.9 KiB
HTML
89 lines
3.9 KiB
HTML
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<head>
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<title>Using as: MIPS FP ABI History</title>
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<link href="AS-Index.html#AS-Index" rel="index" title="AS Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="MIPS-FP-ABIs.html#MIPS-FP-ABIs" rel="up" title="MIPS FP ABIs">
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<a name="MIPS-FP-ABI-History"></a>
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<div class="header">
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<p>
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Next: <a href="MIPS-FP-ABI-Variants.html#MIPS-FP-ABI-Variants" accesskey="n" rel="next">MIPS FP ABI Variants</a>, Up: <a href="MIPS-FP-ABIs.html#MIPS-FP-ABIs" accesskey="u" rel="up">MIPS FP ABIs</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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</div>
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<hr>
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<a name="History-of-FP-ABIs"></a>
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<h4 class="subsubsection">9.27.9.1 History of FP ABIs</h4>
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<a name="index-_002egnu_005fattribute-4_002c-n-directive_002c-MIPS"></a>
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<a name="index-_002egnu_005fattribute-Tag_005fGNU_005fMIPS_005fABI_005fFP_002c-n-directive_002c-MIPS"></a>
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<p>The MIPS ABIs support a variety of different floating-point extensions
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where calling-convention and register sizes vary for floating-point data.
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The extensions exist to support a wide variety of optional architecture
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features. The resulting ABI variants are generally incompatible with each
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other and must be tracked carefully.
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</p>
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<p>Traditionally the use of an explicit <code>.gnu_attribute 4, <var>n</var></code>
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directive is used to indicate which ABI is in use by a specific module.
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It was then left to the user to ensure that command line options and the
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selected ABI were compatible with some potential for inconsistencies.
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</p>
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</body>
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</html>
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