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diff --git a/docs/LangRef.html b/docs/LangRef.html index f1abdb5..04eb45d 100644 --- a/docs/LangRef.html +++ b/docs/LangRef.html @@ -255,6 +255,12 @@ <li><a href="#int_umul_overflow">'<tt>llvm.umul.with.overflow.*</tt> Intrinsics</a></li> </ol> </li> + <li><a href="#int_fp16">Half Precision Floating Point Intrinsics</a> + <ol> + <li><a href="#int_convert_to_fp16">'<tt>llvm.convert.to.fp16</tt>' Intrinsic</a></li> + <li><a href="#int_convert_from_fp16">'<tt>llvm.convert.from.fp16</tt>' Intrinsic</a></li> + </ol> + </li> <li><a href="#int_debugger">Debugger intrinsics</a></li> <li><a href="#int_eh">Exception Handling intrinsics</a></li> <li><a href="#int_trampoline">Trampoline Intrinsic</a> @@ -691,9 +697,9 @@ define i32 @main() { <i>; i32()* </i> target, without having to conform to an externally specified ABI (Application Binary Interface). <a href="CodeGenerator.html#tailcallopt">Tail calls can only be optimized - when this convention is used.</a> This calling convention does not - support varargs and requires the prototype of all callees to exactly match - the prototype of the function definition.</dd> + when this or the GHC convention is used.</a> This calling convention + does not support varargs and requires the prototype of all callees to + exactly match the prototype of the function definition.</dd> <dt><b>"<tt>coldcc</tt>" - The cold calling convention</b>:</dt> <dd>This calling convention attempts to make code in the caller as efficient @@ -703,6 +709,26 @@ define i32 @main() { <i>; i32()* </i> does not support varargs and requires the prototype of all callees to exactly match the prototype of the function definition.</dd> + <dt><b>"<tt>cc <em>10</em></tt>" - GHC convention</b>:</dt> + <dd>This calling convention has been implemented specifically for use by the + <a href="http://www.haskell.org/ghc">Glasgow Haskell Compiler (GHC)</a>. + It passes everything in registers, going to extremes to achieve this by + disabling callee save registers. This calling convention should not be + used lightly but only for specific situations such as an alternative to + the <em>register pinning</em> performance technique often used when + implementing functional programming languages.At the moment only X86 + supports this convention and it has the following limitations: + <ul> + <li>On <em>X86-32</em> only supports up to 4 bit type parameters. No + floating point types are supported.</li> + <li>On <em>X86-64</em> only supports up to 10 bit type parameters and + 6 floating point parameters.</li> + </ul> + This calling convention supports + <a href="CodeGenerator.html#tailcallopt">tail call optimization</a> but + requires both the caller and callee are using it. + </dd> + <dt><b>"<tt>cc <<em>n</em>></tt>" - Numbered convention</b>:</dt> <dd>Any calling convention may be specified by number, allowing target-specific calling conventions to be used. Target specific calling @@ -6588,6 +6614,97 @@ LLVM</a>.</p> <!-- ======================================================================= --> <div class="doc_subsection"> + <a name="int_fp16">Half Precision Floating Point Intrinsics</a> +</div> + +<div class="doc_text"> + +<p>Half precision floating point is a storage-only format. This means that it is + a dense encoding (in memory) but does not support computation in the + format.</p> + +<p>This means that code must first load the half-precision floating point + value as an i16, then convert it to float with <a + href="#int_convert_from_fp16"><tt>llvm.convert.from.fp16</tt></a>. + Computation can then be performed on the float value (including extending to + double etc). To store the value back to memory, it is first converted to + float if needed, then converted to i16 with + <a href="#int_convert_to_fp16"><tt>llvm.convert.to.fp16</tt></a>, then + storing as an i16 value.</p> +</div> + +<!-- _______________________________________________________________________ --> +<div class="doc_subsubsection"> + <a name="int_convert_to_fp16">'<tt>llvm.convert.to.fp16</tt>' Intrinsic</a> +</div> + +<div class="doc_text"> + +<h5>Syntax:</h5> +<pre> + declare i16 @llvm.convert.to.fp16(f32 %a) +</pre> + +<h5>Overview:</h5> +<p>The '<tt>llvm.convert.to.fp16</tt>' intrinsic function performs + a conversion from single precision floating point format to half precision + floating point format.</p> + +<h5>Arguments:</h5> +<p>The intrinsic function contains single argument - the value to be + converted.</p> + +<h5>Semantics:</h5> +<p>The '<tt>llvm.convert.to.fp16</tt>' intrinsic function performs + a conversion from single precision floating point format to half precision + floating point format. The return value is an <tt>i16</tt> which + contains the converted number.</p> + +<h5>Examples:</h5> +<pre> + %res = call i16 @llvm.convert.to.fp16(f32 %a) + store i16 %res, i16* @x, align 2 +</pre> + +</div> + +<!-- _______________________________________________________________________ --> +<div class="doc_subsubsection"> + <a name="int_convert_from_fp16">'<tt>llvm.convert.from.fp16</tt>' Intrinsic</a> +</div> + +<div class="doc_text"> + +<h5>Syntax:</h5> +<pre> + declare f32 @llvm.convert.from.fp16(i16 %a) +</pre> + +<h5>Overview:</h5> +<p>The '<tt>llvm.convert.from.fp16</tt>' intrinsic function performs + a conversion from half precision floating point format to single precision + floating point format.</p> + +<h5>Arguments:</h5> +<p>The intrinsic function contains single argument - the value to be + converted.</p> + +<h5>Semantics:</h5> +<p>The '<tt>llvm.convert.from.fp16</tt>' intrinsic function performs a + conversion from half single precision floating point format to single + precision floating point format. The input half-float value is represented by + an <tt>i16</tt> value.</p> + +<h5>Examples:</h5> +<pre> + %a = load i16* @x, align 2 + %res = call f32 @llvm.convert.from.fp16(i16 %a) +</pre> + +</div> + +<!-- ======================================================================= --> +<div class="doc_subsection"> <a name="int_debugger">Debugger Intrinsics</a> </div> @@ -7473,7 +7590,7 @@ LLVM</a>.</p> <a href="mailto:sabre@nondot.org">Chris Lattner</a><br> <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br> - Last modified: $Date: 2010-03-08 22:05:02 +0100 (Mon, 08 Mar 2010) $ + Last modified: $Date: 2010-03-15 05:12:21 +0100 (Mon, 15 Mar 2010) $ </address> </body> |
