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diff --git a/docs/LangRef.html b/docs/LangRef.html index d5abdce..f5406f5 100644 --- a/docs/LangRef.html +++ b/docs/LangRef.html @@ -101,7 +101,6 @@ <li><a href="#i_cast">'<tt>cast .. to</tt>' Instruction</a></li> <li><a href="#i_select">'<tt>select</tt>' Instruction</a></li> <li><a href="#i_call">'<tt>call</tt>' Instruction</a></li> - <li><a href="#i_vanext">'<tt>vanext</tt>' Instruction</a></li> <li><a href="#i_vaarg">'<tt>vaarg</tt>' Instruction</a></li> </ol> </li> @@ -2211,58 +2210,6 @@ the <a href="#i_invoke">invoke</a> instruction.</p> <!-- _______________________________________________________________________ --> <div class="doc_subsubsection"> - <a name="i_vanext">'<tt>vanext</tt>' Instruction</a> -</div> - -<div class="doc_text"> - -<h5>Syntax:</h5> - -<pre> - <resultarglist> = vanext <va_list> <arglist>, <argty> -</pre> - -<h5>Overview:</h5> - -<p>The '<tt>vanext</tt>' instruction is used to access arguments passed -through the "variable argument" area of a function call. It is used to -implement the <tt>va_arg</tt> macro in C.</p> - -<h5>Arguments:</h5> - -<p>This instruction takes a <tt>va_list</tt> value and the type of the -argument. It returns another <tt>va_list</tt>. The actual type of -<tt>va_list</tt> may be defined differently for different targets. Most targets -use a <tt>va_list</tt> type of <tt>sbyte*</tt> or some other pointer type.</p> - -<h5>Semantics:</h5> - -<p>The '<tt>vanext</tt>' instruction advances the specified <tt>va_list</tt> -past an argument of the specified type. In conjunction with the <a - href="#i_vaarg"><tt>vaarg</tt></a> instruction, it is used to implement -the <tt>va_arg</tt> macro available in C. For more information, see -the variable argument handling <a href="#int_varargs">Intrinsic -Functions</a>.</p> - -<p>It is legal for this instruction to be called in a function which -does not take a variable number of arguments, for example, the <tt>vfprintf</tt> -function.</p> - -<p><tt>vanext</tt> is an LLVM instruction instead of an <a -href="#intrinsics">intrinsic function</a> because it takes a type as an -argument. The type refers to the current argument in the <tt>va_list</tt>; it -tells the compiler how far on the stack it needs to advance to find the next -argument.</p> - -<h5>Example:</h5> - -<p>See the <a href="#int_varargs">variable argument processing</a> -section.</p> - -</div> - -<!-- _______________________________________________________________________ --> -<div class="doc_subsubsection"> <a name="i_vaarg">'<tt>vaarg</tt>' Instruction</a> </div> @@ -2271,34 +2218,35 @@ section.</p> <h5>Syntax:</h5> <pre> - <resultval> = vaarg <va_list> <arglist>, <argty> + <resultval> = va_arg <va_list*> <arglist>, <argty> </pre> <h5>Overview:</h5> -<p>The '<tt>vaarg</tt>' instruction is used to access arguments passed through +<p>The '<tt>va_arg</tt>' instruction is used to access arguments passed through the "variable argument" area of a function call. It is used to implement the <tt>va_arg</tt> macro in C.</p> <h5>Arguments:</h5> -<p>This instruction takes a <tt>va_list</tt> value and the type of the -argument. It returns a value of the specified argument type. Again, the actual -type of <tt>va_list</tt> is target specific.</p> +<p>This instruction takes a <tt>va_list*</tt> value and the type of +the argument. It returns a value of the specified argument type and +increments the <tt>va_list</tt> to poin to the next argument. Again, the +actual type of <tt>va_list</tt> is target specific.</p> <h5>Semantics:</h5> -<p>The '<tt>vaarg</tt>' instruction loads an argument of the specified type from -the specified <tt>va_list</tt>. In conjunction with the <a -href="#i_vanext"><tt>vanext</tt></a> instruction, it is used to implement the -<tt>va_arg</tt> macro available in C. For more information, see the variable -argument handling <a href="#int_varargs">Intrinsic Functions</a>.</p> +<p>The '<tt>va_arg</tt>' instruction loads an argument of the specified +type from the specified <tt>va_list</tt> and causes the +<tt>va_list</tt> to point to the next argument. For more information, +see the variable argument handling <a href="#int_varargs">Intrinsic +Functions</a>.</p> <p>It is legal for this instruction to be called in a function which does not take a variable number of arguments, for example, the <tt>vfprintf</tt> function.</p> -<p><tt>vaarg</tt> is an LLVM instruction instead of an <a +<p><tt>va_arg</tt> is an LLVM instruction instead of an <a href="#intrinsics">intrinsic function</a> because it takes a type as an argument.</p> @@ -2361,20 +2309,20 @@ used.</p> <pre> int %test(int %X, ...) { ; Initialize variable argument processing - %ap = call sbyte* %<a href="#i_va_start">llvm.va_start</a>() + %ap = alloca sbyte* + call void %<a href="#i_va_start">llvm.va_start</a>(sbyte** %ap) ; Read a single integer argument - %tmp = vaarg sbyte* %ap, int - - ; Advance to the next argument - %ap2 = vanext sbyte* %ap, int + %tmp = va_arg sbyte** %ap, int ; Demonstrate usage of llvm.va_copy and llvm.va_end - %aq = call sbyte* %<a href="#i_va_copy">llvm.va_copy</a>(sbyte* %ap2) - call void %<a href="#i_va_end">llvm.va_end</a>(sbyte* %aq) + %aq = alloca sbyte* + %apv = load sbyte** %ap + call void %<a href="#i_va_copy">llvm.va_copy</a>(sbyte** %aq, sbyte* %apv) + call void %<a href="#i_va_end">llvm.va_end</a>(sbyte** %aq) ; Stop processing of arguments. - call void %<a href="#i_va_end">llvm.va_end</a>(sbyte* %ap2) + call void %<a href="#i_va_end">llvm.va_end</a>(sbyte** %ap) ret int %tmp } </pre> @@ -2388,19 +2336,25 @@ int %test(int %X, ...) { <div class="doc_text"> <h5>Syntax:</h5> -<pre> declare <va_list> %llvm.va_start()<br></pre> +<pre> declare void %llvm.va_start(<va_list>* <arglist>)<br></pre> <h5>Overview:</h5> -<p>The '<tt>llvm.va_start</tt>' intrinsic returns a new <tt><arglist></tt> -for subsequent use by the variable argument intrinsics.</p> +<P>The '<tt>llvm.va_start</tt>' intrinsic initializes +<tt>*<arglist></tt> for subsequent use by <tt><a +href="#i_va_arg">va_arg</a></tt>.</p> + +<h5>Arguments:</h5> + +<P>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p> + <h5>Semantics:</h5> -<p>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt> -macro available in C. In a target-dependent way, it initializes and -returns a <tt>va_list</tt> element, so that the next <tt>vaarg</tt> -will produce the first variable argument passed to the function. Unlike -the C <tt>va_start</tt> macro, this intrinsic does not need to know the -last argument of the function; the compiler can figure that out.</p> -<p>Note that this intrinsic function is only legal to be called from -within the body of a variable argument function.</p> + +<P>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt> +macro available in C. In a target-dependent way, it initializes the +<tt>va_list</tt> element the argument points to, so that the next call to +<tt>va_arg</tt> will produce the first variable argument passed to the function. +Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the +last argument of the function, the compiler can figure that out.</p> + </div> <!-- _______________________________________________________________________ --> @@ -2410,7 +2364,7 @@ within the body of a variable argument function.</p> <div class="doc_text"> <h5>Syntax:</h5> -<pre> declare void %llvm.va_end(<va_list> <arglist>)<br></pre> +<pre> declare void %llvm.va_end(<va_list*> <arglist>)<br></pre> <h5>Overview:</h5> <p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt><arglist></tt> which has been initialized previously with <tt><a href="#i_va_start">llvm.va_start</a></tt> @@ -2435,24 +2389,27 @@ with calls to <tt>llvm.va_end</tt>.</p> <h5>Syntax:</h5> <pre> - declare <va_list> %llvm.va_copy(<va_list> <destarglist>) + declare void %llvm.va_copy(<va_list>* <destarglist>, + <va_list> <srcarglist>) </pre> <h5>Overview:</h5> -<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position -from the source argument list to the destination argument list.</p> +<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position from +the source argument list to the destination argument list.</p> <h5>Arguments:</h5> -<p>The argument is the <tt>va_list</tt> to copy.</p> +<p>The first argument is a pointer to a <tt>va_list</tt> element to initialize. +The second argument is a <tt>va_list</tt> element to copy from.</p> + <h5>Semantics:</h5> -<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt> -macro available in C. In a target-dependent way, it copies the source -<tt>va_list</tt> element into the returned list. This intrinsic is necessary -because the <tt><a href="#i_va_start">llvm.va_start</a></tt> intrinsic may be +<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt> macro +available in C. In a target-dependent way, it copies the source +<tt>va_list</tt> element into the destination list. This intrinsic is necessary +because the <tt><a href="i_va_begin">llvm.va_begin</a></tt> intrinsic may be arbitrarily complex and require memory allocation, for example.</p> </div> |