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diff --git a/docs/TableGenFundamentals.html b/docs/TableGenFundamentals.html index 92b90e6..a211389 100644 --- a/docs/TableGenFundamentals.html +++ b/docs/TableGenFundamentals.html @@ -37,6 +37,7 @@ <ol> <li><a href="#include">File inclusion</a></li> <li><a href="#globallet">'let' expressions</a></li> + <li><a href="#foreach">'foreach' blocks</a></li> </ol></li> </ol></li> <li><a href="#backends">TableGen backends</a> @@ -208,6 +209,14 @@ file, to factor out the common features that instructions of its class share. A key feature of TableGen is that it allows the end-user to define the abstractions they prefer to use when describing their information.</p> +<p>Each def record has a special entry called "NAME." This is the +name of the def ("ADD32rr" above). In the general case def names can +be formed from various kinds of string processing expressions and NAME +resolves to the final value obtained after resolving all of those +expressions. The user may refer to NAME anywhere she desires to use +the ultimate name of the def. NAME should not be defined anywhere +else in user code to avoid conflict problems.</p> + </div> <!-- ======================================================================= --> @@ -393,6 +402,14 @@ which case the user must specify it explicitly.</dd> <dt><tt>list[4-7,17,2-3]</tt></dt> <dd>A slice of the 'list' list, including elements 4,5,6,7,17,2, and 3 from it. Elements may be included multiple times.</dd> +<dt><tt>foreach <var> = <list> in { <body> }</tt></dt> +<dt><tt>foreach <var> = <list> in <def></tt></dt> + <dd> Replicate <body> or <def>, replacing instances of + <var> with each value in <list>. <var> is scoped at the + level of the <tt>foreach</tt> loop and must not conflict with any other object + introduced in <body> or <def>. Currently only <tt>def</tt>s are + expanded within <body>. + </dd> <dt><tt>(DEF a, b)</tt></dt> <dd>a dag value. The first element is required to be a record definition, the remaining elements in the list may be arbitrary other values, including nested @@ -400,6 +417,10 @@ which case the user must specify it explicitly.</dd> <dt><tt>!strconcat(a, b)</tt></dt> <dd>A string value that is the result of concatenating the 'a' and 'b' strings.</dd> +<dt><tt>str1#str2</tt></dt> + <dd>"#" (paste) is a shorthand for !strconcat. It may concatenate + things that are not quoted strings, in which case an implicit + !cast<string> is done on the operand of the paste.</dd> <dt><tt>!cast<type>(a)</tt></dt> <dd>A symbol of type <em>type</em> obtained by looking up the string 'a' in the symbol table. If the type of 'a' does not match <em>type</em>, TableGen @@ -868,6 +889,39 @@ several levels of multiclass instanciations. This also avoids the need of using </pre> </div> +<!-- --------------------------------------------------------------------------> +<h4> + <a name="foreach">Looping</a> +</h4> + +<div> +<p>TableGen supports the '<tt>foreach</tt>' block, which textually replicates +the loop body, substituting iterator values for iterator references in the +body. Example:</p> + +<div class="doc_code"> +<pre> +<b>foreach</b> i = [0, 1, 2, 3] in { + <b>def</b> R#i : Register<...>; + <b>def</b> F#i : Register<...>; +} +</pre> +</div> + +<p>This will create objects <tt>R0</tt>, <tt>R1</tt>, <tt>R2</tt> and +<tt>R3</tt>. <tt>foreach</tt> blocks may be nested. If there is only +one item in the body the braces may be elided:</p> + +<div class="doc_code"> +<pre> +<b>foreach</b> i = [0, 1, 2, 3] in + <b>def</b> R#i : Register<...>; + +</pre> +</div> + +</div> + </div> </div> @@ -912,7 +966,7 @@ This should highlight the APIs in <tt>TableGen/Record.h</tt>.</p> <a href="mailto:sabre@nondot.org">Chris Lattner</a><br> <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br> - Last modified: $Date: 2011-11-03 07:43:23 +0100 (Thu, 03 Nov 2011) $ + Last modified: $Date: 2012-03-27 13:25:16 +0200 (Tue, 27 Mar 2012) $ </address> </body> |
