<li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li>
</ol>
</li>
-
<li><a href="#int_atomics">Atomic intrinsics</a>
-
<li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
-
<li><a href="#int_atomic_cmp_swap"><tt>llvm.atomic.cmp.swap</tt></a></li>
-
<li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
-
<li><a href="#int_atomic_load_add"><tt>llvm.atomic.load.add</tt></a></li>
-
<li><a href="#int_atomic_load_sub"><tt>llvm.atomic.load.sub</tt></a></li>
-
<li><a href="#int_atomic_load_and"><tt>llvm.atomic.load.and</tt></a></li>
-
<li><a href="#int_atomic_load_nand"><tt>llvm.atomic.load.nand</tt></a></li>
-
<li><a href="#int_atomic_load_or"><tt>llvm.atomic.load.or</tt></a></li>
-
<li><a href="#int_atomic_load_xor"><tt>llvm.atomic.load.xor</tt></a></li>
-
<li><a href="#int_atomic_load_max"><tt>llvm.atomic.load.max</tt></a></li>
-
<li><a href="#int_atomic_load_min"><tt>llvm.atomic.load.min</tt></a></li>
-
<li><a href="#int_atomic_load_umax"><tt>llvm.atomic.load.umax</tt></a></li>
-
<li><a href="#int_atomic_load_umin"><tt>llvm.atomic.load.umin</tt></a></li>
- </ol>
- </li>
+ <li><a href="#int_atomics">Atomic intrinsics</a>
+ <ol>
+ <li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
+ <li><a href="#int_atomic_cmp_swap"><tt>llvm.atomic.cmp.swap</tt></a></li>
+ <li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
+ <li><a href="#int_atomic_load_add"><tt>llvm.atomic.load.add</tt></a></li>
+ <li><a href="#int_atomic_load_sub"><tt>llvm.atomic.load.sub</tt></a></li>
+ <li><a href="#int_atomic_load_and"><tt>llvm.atomic.load.and</tt></a></li>
+ <li><a href="#int_atomic_load_nand"><tt>llvm.atomic.load.nand</tt></a></li>
+ <li><a href="#int_atomic_load_or"><tt>llvm.atomic.load.or</tt></a></li>
+ <li><a href="#int_atomic_load_xor"><tt>llvm.atomic.load.xor</tt></a></li>
+ <li><a href="#int_atomic_load_max"><tt>llvm.atomic.load.max</tt></a></li>
+ <li><a href="#int_atomic_load_min"><tt>llvm.atomic.load.min</tt></a></li>
+ <li><a href="#int_atomic_load_umax"><tt>llvm.atomic.load.umax</tt></a></li>
+ <li><a href="#int_atomic_load_umin"><tt>llvm.atomic.load.umin</tt></a></li>
+ </ol>
+ </li>
<li><a href="#int_general">General intrinsics</a>
<ol>
<li><a href="#int_var_annotation">
- <tt>llvm.var.annotation</tt>' Intrinsic</a></li>
+ '<tt>llvm.var.annotation</tt>' Intrinsic</a></li>
<li><a href="#int_annotation">
- <tt>llvm.annotation.*</tt>' Intrinsic</a></li>
+ '<tt>llvm.annotation.*</tt>' Intrinsic</a></li>
<li><a href="#int_trap">
- <tt>llvm.trap</tt>' Intrinsic</a></li>
+ '<tt>llvm.trap</tt>' Intrinsic</a></li>
+ <li><a href="#int_stackprotector">
+ '<tt>llvm.stackprotector</tt>' Intrinsic</a></li>
</ol>
</li>
</ol>
</dl>
-<p><a name="linkage_external"></a>For example, since the "<tt>.LC0</tt>"
+<p>For example, since the "<tt>.LC0</tt>"
variable is defined to be internal, if another module defined a "<tt>.LC0</tt>"
variable and was linked with this one, one of the two would be renamed,
preventing a collision. Since "<tt>main</tt>" and "<tt>puts</tt>" are
return values. </dd>
<dt><tt>noalias</tt></dt>
- <dd>This indicates that the parameter does not alias any global or any other
- parameter. The caller is responsible for ensuring that this is the case,
- usually by placing the value in a stack allocation. This is not a valid
- attribute for return values.</dd>
+ <dd>This indicates that the pointer does not alias any global or any other
+ parameter. The caller is responsible for ensuring that this is the
+ case. On a function return value, <tt>noalias</tt> additionally indicates
+ that the pointer does not alias any other pointers visible to the
+ caller. Note that this applies only to pointers that can be used to actually
+ load/store a value: NULL, unique pointers from malloc(0), and freed pointers
+ are considered to not alias anything.</dd>
<dt><tt>nest</tt></dt>
<dd>This indicates that the pointer parameter can be excised using the
protector. It is in the form of a "canary"—a random value placed on the
stack before the local variables that's checked upon return from the function to
see if it has been overwritten. A heuristic is used to determine if a function
-needs stack protectors or not.</dd>
+needs stack protectors or not.
-<dt><tt>ssp-req</tt></dt>
+<p>If a function that has an <tt>ssp</tt> attribute is inlined into a function
+that doesn't have an <tt>ssp</tt> attribute, then the resulting function will
+have an <tt>ssp</tt> attribute.</p></dd>
+
+<dt><tt>sspreq</tt></dt>
<dd>This attribute indicates that the function should <em>always</em> emit a
stack smashing protector. This overrides the <tt><a href="#ssp">ssp</a></tt>
-function attribute.</dd>
+function attribute.
+
+<p>If a function that has an <tt>sspreq</tt> attribute is inlined into a
+function that doesn't have an <tt>sspreq</tt> attribute or which has
+an <tt>ssp</tt> attribute, then the resulting function will have
+an <tt>sspreq</tt> attribute.</p></dd>
</dl>
</div>
</td>
</tr><tr class="layout">
<td class="left"><tt>{i32, i32} (i32)</tt></td>
- <td class="left">A function taking an <tt>i32></tt>, returning two
- <tt> i32 </tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
+ <td class="left">A function taking an <tt>i32</tt>, returning two
+ <tt>i32</tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
</td>
</tr>
</table>
<h5>Semantics:</h5>
<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
-a pointer is returned. The result of a zero byte allocattion is undefined. The
+a pointer is returned. The result of a zero byte allocation is undefined. The
result is null if there is insufficient memory available.</p>
<h5>Example:</h5>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memcpy on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memcpy.i8(i8 * <dest>, i8 * <src>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memcpy.i16(i8 * <dest>, i8 * <src>,
+ i16 <len>, i32 <align>)
declare void @llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
declare void @llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memmove on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memmove.i8(i8 * <dest>, i8 * <src>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memmove.i16(i8 * <dest>, i8 * <src>,
+ i16 <len>, i32 <align>)
declare void @llvm.memmove.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
declare void @llvm.memmove.i64(i8 * <dest>, i8 * <src>,
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memset on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memset.i8(i8 * <dest>, i8 <val>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memset.i16(i8 * <dest>, i8 <val>,
+ i16 <len>, i32 <align>)
declare void @llvm.memset.i32(i8 * <dest>, i8 <val>,
i32 <len>, i32 <align>)
declare void @llvm.memset.i64(i8 * <dest>, i8 <val>,
</p>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_stackprotector">'<tt>llvm.stackprotector</tt>' Intrinsic</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre>
+declare void @llvm.stackprotector( i8* <guard>, i8** <slot> )
+
+</pre>
+<h5>Overview:</h5>
+<p>
+ The <tt>llvm.stackprotector</tt> intrinsic takes the <tt>guard</tt> and stores
+ it onto the stack at <tt>slot</tt>. The stack slot is adjusted to ensure that
+ it is placed on the stack before local variables.
+</p>
+<h5>Arguments:</h5>
+<p>
+ The <tt>llvm.stackprotector</tt> intrinsic requires two pointer arguments. The
+ first argument is the value loaded from the stack guard
+ <tt>@__stack_chk_guard</tt>. The second variable is an <tt>alloca</tt> that
+ has enough space to hold the value of the guard.
+</p>
+<h5>Semantics:</h5>
+<p>
+ This intrinsic causes the prologue/epilogue inserter to force the position of
+ the <tt>AllocaInst</tt> stack slot to be before local variables on the
+ stack. This is to ensure that if a local variable on the stack is overwritten,
+ it will destroy the value of the guard. When the function exits, the guard on
+ the stack is checked against the original guard. If they're different, then
+ the program aborts by calling the <tt>__stack_chk_fail()</tt> function.
+</p>
+</div>
+
<!-- *********************************************************************** -->
<hr>
<address>
projects / oota-llvm.git / blobdiff