<li><a href="#int_exp">'<tt>llvm.exp.*</tt>' Intrinsic</a></li>
<li><a href="#int_log">'<tt>llvm.log.*</tt>' Intrinsic</a></li>
<li><a href="#int_fma">'<tt>llvm.fma.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_fabs">'<tt>llvm.fabs.*</tt>' Intrinsic</a></li>
</ol>
</li>
<li><a href="#int_manip">Bit Manipulation Intrinsics</a>
'<tt>llvm.debugtrap</tt>' Intrinsic</a></li>
<li><a href="#int_stackprotector">
'<tt>llvm.stackprotector</tt>' Intrinsic</a></li>
- <li><a href="#int_objectsize">
+
<li><a href="#int_objectsize">
'<tt>llvm.objectsize</tt>' Intrinsic</a></li>
- <li><a href="#int_expect">
+
<li><a href="#int_expect">
'<tt>llvm.expect</tt>' Intrinsic</a></li>
+ <li><a href="#int_donothing">
+ '<tt>llvm.donothing</tt>' Intrinsic</a></li>
</ol>
</li>
</ol>
<p>Global variables define regions of memory allocated at compilation time
instead of run-time. Global variables may optionally be initialized, may
have an explicit section to be placed in, and may have an optional explicit
- alignment specified. A variable may be defined as "thread_local", which
+ alignment specified.</p>
+
+<p>A variable may be defined as <tt>thread_local</tt>, which
means that it will not be shared by threads (each thread will have a
- separated copy of the variable). A variable may be defined as a global
+ separated copy of the variable). Not all targets support thread-local
+ variables. Optionally, a TLS model may be specified:</p>
+
+<dl>
+ <dt><b><tt>localdynamic</tt></b>:</dt>
+ <dd>For variables that are only used within the current shared library.</dd>
+
+ <dt><b><tt>initialexec</tt></b>:</dt>
+ <dd>For variables in modules that will not be loaded dynamically.</dd>
+
+ <dt><b><tt>localexec</tt></b>:</dt>
+ <dd>For variables defined in the executable and only used within it.</dd>
+</dl>
+
+<p>The models correspond to the ELF TLS models; see
+ <a href="http://people.redhat.com/drepper/tls.pdf">ELF
+ Handling For Thread-Local Storage</a> for more information on under which
+ circumstances the different models may be used. The target may choose a
+ different TLS model if the specified model is not supported, or if a better
+ choice of model can be made.</p>
+
+<p>A variable may be defined as a global
"constant," which indicates that the contents of the variable
will <b>never</b> be modified (enabling better optimization, allowing the
global data to be placed in the read-only section of an executable, etc).
@G = addrspace(5) constant float 1.0, section "foo", align 4
</pre>
+<p>The following example defines a thread-local global with
+ the <tt>initialexec</tt> TLS model:</p>
+
+<pre class="doc_code">
+@G = thread_local(initialexec) global i32 0, align 4
+</pre>
+
</div>
<li>If no match is found, and the type sought is an integer type, then the
smallest integer type that is larger than the bitwidth of the sought type
is used. If none of the specifications are larger than the bitwidth then
- the the largest integer type is used. For example, given the default
+ the largest integer type is used. For example, given the default
specifications above, the i7 type will use the alignment of i8 (next
largest) while both i65 and i256 will use the alignment of i64 (largest
specified).</li>
</pre>
<p>Inline assembler expressions may <b>only</b> be used as the callee operand of
- a <a href="#i_call"><tt>call</tt> instruction</a>. Thus, typically we
- have:</p>
+ a <a href="#i_call"><tt>call</tt></a> or an
+ <a href="#i_invoke"><tt>invoke</tt></a> instruction.
+ Thus, typically we have:</p>
<pre class="doc_code">
%X = call i32 asm "<a href="#int_bswap">bswap</a> $0", "=r,r"(i32 %Y)
</div>
+<!-- _______________________________________________________________________ -->
+<h4>
+ <a name="int_fabs">'<tt>llvm.fabs.*</tt>' Intrinsic</a>
+</h4>
+
+<div>
+
+<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.fabs</tt> on any
+ floating point or vector of floating point type. Not all targets support all
+ types however.</p>
+
+<pre>
+ declare float @llvm.fabs.f32(float %Val)
+ declare double @llvm.fabs.f64(double %Val)
+ declare x86_fp80 @llvm.fabs.f80(x86_fp80 %Val)
+ declare fp128 @llvm.fabs.f128(fp128 %Val)
+ declare ppc_fp128 @llvm.fabs.ppcf128(ppc_fp128 %Val)
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>llvm.fabs.*</tt>' intrinsics return the absolute value of
+ the operand.</p>
+
+<h5>Arguments:</h5>
+<p>The argument and return value are floating point numbers of the same
+ type.</p>
+
+<h5>Semantics:</h5>
+<p>This function returns the same values as the libm <tt>fabs</tt> functions
+ would, and handles error conditions in the same way.</p>
+
+</div>
+
</div>
<!-- ======================================================================= -->
<p>This intrinsic is lowered to the <tt>val</tt>.</p>
</div>
+<!-- _______________________________________________________________________ -->
+<h4>
+ <a name="int_donothing">'<tt>llvm.donothing</tt>' Intrinsic</a>
+</h4>
+
+<div>
+
+<h5>Syntax:</h5>
+<pre>
+ declare void @llvm.donothing() nounwind readnone
+</pre>
+
+<h5>Overview:</h5>
+<p>The <tt>llvm.donothing</tt> intrinsic doesn't perform any operation. It's the
+only intrinsic that can be called with an invoke instruction.</p>
+
+<h5>Arguments:</h5>
+<p>None.</p>
+
+<h5>Semantics:</h5>
+<p>This intrinsic does nothing, and it's removed by optimizers and ignored by
+codegen.</p>
+</div>
+
</div>
</div>
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