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Diffstat (limited to 'docs/LangRef.html')
| -rw-r--r-- | docs/LangRef.html | 71 |
1 files changed, 53 insertions, 18 deletions
diff --git a/docs/LangRef.html b/docs/LangRef.html index 2b9ee24bf4..0ec08eb0a0 100644 --- a/docs/LangRef.html +++ b/docs/LangRef.html @@ -275,9 +275,10 @@ </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> + <li><a href="#int_trampoline">Trampoline Intrinsics</a> <ol> <li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li> + <li><a href="#int_at">'<tt>llvm.adjust.trampoline</tt>' Intrinsic</a></li> </ol> </li> <li><a href="#int_atomics">Atomic intrinsics</a> @@ -7680,12 +7681,12 @@ LLVM</a>.</p> <!-- ======================================================================= --> <h3> - <a name="int_trampoline">Trampoline Intrinsic</a> + <a name="int_trampoline">Trampoline Intrinsics</a> </h3> <div> -<p>This intrinsic makes it possible to excise one parameter, marked with +<p>These intrinsics make it possible to excise one parameter, marked with the <a href="#nest"><tt>nest</tt></a> attribute, from a function. The result is a callable function pointer lacking the nest parameter - the caller does not need to @@ -7702,7 +7703,8 @@ LLVM</a>.</p> <pre class="doc_code"> %tramp = alloca [10 x i8], align 4 ; size and alignment only correct for X86 %tramp1 = getelementptr [10 x i8]* %tramp, i32 0, i32 0 - %p = call i8* @llvm.init.trampoline(i8* %tramp1, i8* bitcast (i32 (i8*, i32, i32)* @f to i8*), i8* %nval) + call i8* @llvm.init.trampoline(i8* %tramp1, i8* bitcast (i32 (i8*, i32, i32)* @f to i8*), i8* %nval) + %p = call i8* @llvm.adjust.trampoline(i8* %tramp1) %fp = bitcast i8* %p to i32 (i32, i32)* </pre> @@ -7720,12 +7722,12 @@ LLVM</a>.</p> <h5>Syntax:</h5> <pre> - declare i8* @llvm.init.trampoline(i8* <tramp>, i8* <func>, i8* <nval>) + declare void @llvm.init.trampoline(i8* <tramp>, i8* <func>, i8* <nval>) </pre> <h5>Overview:</h5> -<p>This fills the memory pointed to by <tt>tramp</tt> with code and returns a - function pointer suitable for executing it.</p> +<p>This fills the memory pointed to by <tt>tramp</tt> with executable code, + turning it into a trampoline.</p> <h5>Arguments:</h5> <p>The <tt>llvm.init.trampoline</tt> intrinsic takes three arguments, all @@ -7739,17 +7741,50 @@ LLVM</a>.</p> <h5>Semantics:</h5> <p>The block of memory pointed to by <tt>tramp</tt> is filled with target - dependent code, turning it into a function. A pointer to this function is - returned, but needs to be bitcast to an <a href="#int_trampoline">appropriate - function pointer type</a> before being called. The new function's signature - is the same as that of <tt>func</tt> with any arguments marked with - the <tt>nest</tt> attribute removed. At most one such <tt>nest</tt> argument - is allowed, and it must be of pointer type. Calling the new function is - equivalent to calling <tt>func</tt> with the same argument list, but - with <tt>nval</tt> used for the missing <tt>nest</tt> argument. If, after - calling <tt>llvm.init.trampoline</tt>, the memory pointed to - by <tt>tramp</tt> is modified, then the effect of any later call to the - returned function pointer is undefined.</p> + dependent code, turning it into a function. Then <tt>tramp</tt> needs to be + passed to <a href="#int_at">llvm.adjust.trampoline</a> to get a pointer + which can be <a href="#int_trampoline">bitcast (to a new function) and + called</a>. The new function's signature is the same as that of + <tt>func</tt> with any arguments marked with the <tt>nest</tt> attribute + removed. At most one such <tt>nest</tt> argument is allowed, and it must be of + pointer type. Calling the new function is equivalent to calling <tt>func</tt> + with the same argument list, but with <tt>nval</tt> used for the missing + <tt>nest</tt> argument. If, after calling <tt>llvm.init.trampoline</tt>, the + memory pointed to by <tt>tramp</tt> is modified, then the effect of any later call + to the returned function pointer is undefined.</p> +</div> + +<!-- _______________________________________________________________________ --> +<h4> + <a name="int_at"> + '<tt>llvm.adjust.trampoline</tt>' Intrinsic + </a> +</h4> + +<div> + +<h5>Syntax:</h5> +<pre> + declare i8* @llvm.adjust.trampoline(i8* <tramp>) +</pre> + +<h5>Overview:</h5> +<p>This performs any required machine-specific adjustment to the address of a + trampoline (passed as <tt>tramp</tt>).</p> + +<h5>Arguments:</h5> +<p><tt>tramp</tt> must point to a block of memory which already has trampoline code + filled in by a previous call to <a href="#int_it"><tt>llvm.init.trampoline</tt> + </a>.</p> + +<h5>Semantics:</h5> +<p>On some architectures the address of the code to be executed needs to be + different to the address where the trampoline is actually stored. This + intrinsic returns the executable address corresponding to <tt>tramp</tt> + after performing the required machine specific adjustments. + The pointer returned can then be <a href="#int_trampoline"> bitcast and + executed</a>. +</p> </div> |