| 1 | <?xml version="1.0" encoding="ISO-8859-1"?> |
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| 2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
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| 3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ |
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| 4 | <!ENTITY % general-entities SYSTEM "../../general.ent"> |
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| 5 | %general-entities; |
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| 6 | ]> |
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| 7 | |
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| 8 | <sect1 id="ch-system-abi"> |
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| 9 | <?dbhtml filename="abi.html"?> |
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| 10 | |
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| 11 | <title>ABI Variables</title> |
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| 12 | |
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| 13 | <para os="a">On the ARM architecture, there are two major ABI types to choose |
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| 14 | from: EABI and OABI. There is also a Thumb ABI and an Intel IWMMX specific |
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| 15 | ABI but these are generally not recommended for most uses.</para> |
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| 16 | |
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| 17 | <para os="b">The EABI (Embedded ABI) is newer and supports additional |
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| 18 | features, faster software floating point operations, and Thumb interworking, |
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| 19 | but is only compatible with ARMv4t and newer cores. The EABI has |
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| 20 | sub-ABIs of: aapcs-linux and aapcs. aapcs-linux has standard Linux 4 byte |
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| 21 | enums while aapcs has variable length enums. aapcs-linux is recommended over |
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| 22 | aapcs.</para> |
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| 23 | |
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| 24 | <para os="c">The OABI (old ABI) is called apcs-gnu and supports ARMv4 and |
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| 25 | older cores. Generally the OABI is not used by modern ARM processors.</para> |
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| 26 | |
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| 27 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
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| 28 | href="../common/abi.xml" |
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| 29 | xpointer="xpointer(//*[@os='a'])"/> |
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| 30 | |
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| 31 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
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| 32 | href="../common/abi.xml" |
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| 33 | xpointer="xpointer(//*[@os='b'])"/> |
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| 34 | |
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| 35 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
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| 36 | href="../common/abi.xml" |
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| 37 | xpointer="xpointer(//*[@os='c'])"/> |
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| 38 | |
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| 39 | <table> |
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| 40 | <title>List of Build Variables</title> |
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| 41 | <?dbfo table-width="3in" ?> |
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| 42 | |
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| 43 | <tgroup cols="3"> |
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| 44 | |
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| 45 | <colspec colnum="1" colwidth="1.5in" colname="ABI to Select"/> |
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| 46 | <colspec colnum="2" colwidth="1.5in" colname="Variable Value"/> |
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| 47 | <colspec colnum="3" colwidth="2in" colname="Note"/> |
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| 48 | |
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| 49 | <thead> |
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| 50 | <row> |
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| 51 | <entry>ABI</entry> |
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| 52 | <entry>CLFS_ABI=Value</entry> |
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| 53 | <entry>Note</entry> |
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| 54 | </row> |
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| 55 | </thead> |
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| 56 | |
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| 57 | <tbody> |
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| 58 | <row> |
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| 59 | <entry>aapcs-linux</entry> |
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| 60 | <entry>aapcs-linux</entry> |
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| 61 | <entry>Recommended for EABI. Standard Linux 32 bit (int) enums</entry> |
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| 62 | </row> |
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| 63 | <row> |
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| 64 | <entry>apcs-gnu</entry> |
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| 65 | <entry>apcs-gnu</entry> |
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| 66 | <entry>Recommended for OABI</entry> |
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| 67 | </row> |
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| 68 | <row> |
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| 69 | <entry>atpcs</entry> |
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| 70 | <entry>atpcs</entry> |
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| 71 | <entry>Thumb ABI</entry> |
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| 72 | </row> |
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| 73 | <row> |
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| 74 | <entry>aapcs</entry> |
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| 75 | <entry>aapcs</entry> |
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| 76 | <entry>EABI w/ variable size enums</entry> |
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| 77 | </row> |
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| 78 | <row> |
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| 79 | <entry>iwmmxt</entry> |
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| 80 | <entry>iwmmxt</entry> |
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| 81 | <entry>Supports Intel XScale MMX extensions</entry> |
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| 82 | </row> |
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| 83 | </tbody> |
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| 84 | |
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| 85 | </tgroup> |
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| 86 | |
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| 87 | </table> |
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| 88 | |
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| 89 | </sect1> |
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| 90 | |
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