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diff --git a/docs/LangRef.html b/docs/LangRef.html index 08d84df..5959b3d 100644 --- a/docs/LangRef.html +++ b/docs/LangRef.html @@ -74,16 +74,14 @@ <ol> <li><a href="#t_array">Array Type</a></li> <li><a href="#t_struct">Structure Type</a></li> - <li><a href="#t_pstruct">Packed Structure Type</a></li> + <li><a href="#t_opaque">Opaque Type</a></li> <li><a href="#t_vector">Vector Type</a></li> </ol> </li> <li><a href="#t_function">Function Type</a></li> <li><a href="#t_pointer">Pointer Type</a></li> - <li><a href="#t_opaque">Opaque Type</a></li> </ol> </li> - <li><a href="#t_uprefs">Type Up-references</a></li> </ol> </li> <li><a href="#constants">Constants</a> @@ -1535,7 +1533,6 @@ synchronization behavior.</p> <a href="#t_function">function</a>, <a href="#t_pointer">pointer</a>, <a href="#t_struct">structure</a>, - <a href="#t_pstruct">packed structure</a>, <a href="#t_vector">vector</a>, <a href="#t_opaque">opaque</a>. </td> @@ -1703,7 +1700,9 @@ synchronization behavior.</p> possible to have a two dimensional array, using an array as the element type of another array.</p> - +</div> + + <!-- _______________________________________________________________________ --> <h4> <a name="t_aggregate">Aggregate Types</a> @@ -1842,9 +1841,7 @@ synchronization behavior.</p> <h5>Overview:</h5> <p>The structure type is used to represent a collection of data members together - in memory. The packing of the field types is defined to match the ABI of the - underlying processor. The elements of a structure may be any type that has a - size.</p> + in memory. The elements of a structure may be any type that has a size.</p> <p>Structures in memory are accessed using '<tt><a href="#i_load">load</a></tt>' and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a field @@ -1852,66 +1849,76 @@ synchronization behavior.</p> Structures in registers are accessed using the '<tt><a href="#i_extractvalue">extractvalue</a></tt>' and '<tt><a href="#i_insertvalue">insertvalue</a></tt>' instructions.</p> + +<p>Structures may optionally be "packed" structures, which indicate that the + alignment of the struct is one byte, and that there is no padding between + the elements. In non-packed structs, padding between field types is defined + by the target data string to match the underlying processor.</p> + +<p>Structures can either be "anonymous" or "named". An anonymous structure is + defined inline with other types (e.g. <tt>{i32, i32}*</tt>) and a named types + are always defined at the top level with a name. Anonmyous types are uniqued + by their contents and can never be recursive since there is no way to write + one. Named types can be recursive. +</p> + <h5>Syntax:</h5> <pre> - { <type list> } + %T1 = type { <type list> } <i>; Named normal struct type</i> + %T2 = type <{ <type list> }> <i>; Named packed struct type</i> </pre> - + <h5>Examples:</h5> <table class="layout"> <tr class="layout"> <td class="left"><tt>{ i32, i32, i32 }</tt></td> <td class="left">A triple of three <tt>i32</tt> values</td> - </tr><tr class="layout"> + </tr> + <tr class="layout"> <td class="left"><tt>{ float, i32 (i32) * }</tt></td> <td class="left">A pair, where the first element is a <tt>float</tt> and the second element is a <a href="#t_pointer">pointer</a> to a <a href="#t_function">function</a> that takes an <tt>i32</tt>, returning an <tt>i32</tt>.</td> </tr> + <tr class="layout"> + <td class="left"><tt><{ i8, i32 }></tt></td> + <td class="left">A packed struct known to be 5 bytes in size.</td> + </tr> </table> </div> - + <!-- _______________________________________________________________________ --> <h4> - <a name="t_pstruct">Packed Structure Type</a> + <a name="t_opaque">Opaque Type</a> </h4> <div> <h5>Overview:</h5> -<p>The packed structure type is used to represent a collection of data members - together in memory. There is no padding between fields. Further, the - alignment of a packed structure is 1 byte. The elements of a packed - structure may be any type that has a size.</p> - -<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt> and - '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a field with - the '<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.</p> +<p>Opaque types are used to represent named structure types that do not have a + body specified. This corresponds (for example) to the C notion of a forward + declared structure.</p> <h5>Syntax:</h5> <pre> - < { <type list> } > + %X = type opaque + %52 = type opaque </pre> <h5>Examples:</h5> <table class="layout"> <tr class="layout"> - <td class="left"><tt>< { i32, i32, i32 } ></tt></td> - <td class="left">A triple of three <tt>i32</tt> values</td> - </tr><tr class="layout"> - <td class="left"> -<tt>< { float, i32 (i32)* } ></tt></td> - <td class="left">A pair, where the first element is a <tt>float</tt> and the - second element is a <a href="#t_pointer">pointer</a> to a - <a href="#t_function">function</a> that takes an <tt>i32</tt>, returning - an <tt>i32</tt>.</td> + <td class="left"><tt>opaque</tt></td> + <td class="left">An opaque type.</td> </tr> </table> </div> + + <!-- _______________________________________________________________________ --> <h4> <a name="t_pointer">Pointer Type</a> @@ -1999,86 +2006,6 @@ synchronization behavior.</p> </div> -<!-- _______________________________________________________________________ --> -<h4> - <a name="t_opaque">Opaque Type</a> -</h4> - -<div> - -<h5>Overview:</h5> -<p>Opaque types are used to represent unknown types in the system. This - corresponds (for example) to the C notion of a forward declared structure - type. In LLVM, opaque types can eventually be resolved to any type (not just - a structure type).</p> - -<h5>Syntax:</h5> -<pre> - opaque -</pre> - -<h5>Examples:</h5> -<table class="layout"> - <tr class="layout"> - <td class="left"><tt>opaque</tt></td> - <td class="left">An opaque type.</td> - </tr> -</table> - -</div> - -</div> - -<!-- ======================================================================= --> -<h3> - <a name="t_uprefs">Type Up-references</a> -</h3> - -<div> - -<h5>Overview:</h5> -<p>An "up reference" allows you to refer to a lexically enclosing type without - requiring it to have a name. For instance, a structure declaration may - contain a pointer to any of the types it is lexically a member of. Example - of up references (with their equivalent as named type declarations) - include:</p> - -<pre> - { \2 * } %x = type { %x* } - { \2 }* %y = type { %y }* - \1* %z = type %z* -</pre> - -<p>An up reference is needed by the asmprinter for printing out cyclic types - when there is no declared name for a type in the cycle. Because the - asmprinter does not want to print out an infinite type string, it needs a - syntax to handle recursive types that have no names (all names are optional - in llvm IR).</p> - -<h5>Syntax:</h5> -<pre> - \<level> -</pre> - -<p>The level is the count of the lexical type that is being referred to.</p> - -<h5>Examples:</h5> -<table class="layout"> - <tr class="layout"> - <td class="left"><tt>\1*</tt></td> - <td class="left">Self-referential pointer.</td> - </tr> - <tr class="layout"> - <td class="left"><tt>{ { \3*, i8 }, i32 }</tt></td> - <td class="left">Recursive structure where the upref refers to the out-most - structure.</td> - </tr> -</table> - -</div> - -</div> - <!-- *********************************************************************** --> <h2><a name="constants">Constants</a></h2> <!-- *********************************************************************** --> |