<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>
<li><a href="#int_umul_overflow">'<tt>llvm.umul.with.overflow.*</tt> Intrinsics</a></li>
</ol>
</li>
+ <li><a href="#spec_arithmetic">Specialised Arithmetic Intrinsics</a>
+ <ol>
+ <li><a href="#fmuladd">'<tt>llvm.fmuladd</tt> Intrinsic</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>
'<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>
<h5>Arguments:</h5>
<p>The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
- with types that match each other. The third argument is a shuffle mask whose
+ with the same type. The third argument is a shuffle mask whose
element type is always 'i32'. The result of the instruction is a vector
whose length is the same as the shuffle mask and whose element type is the
same as the element type of the first two operands.</p>
</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>
<!-- ======================================================================= -->
</div>
+<!-- ======================================================================= -->
+<h3>
+ <a name="spec_arithmetic">Specialised Arithmetic Intrinsics</a>
+</h3>
+
+<!-- _______________________________________________________________________ -->
+
+<h4>
+ <a name="fmuladd">'<tt>llvm.fmuladd.*</tt>' Intrinsic</a>
+</h4>
+
+<div>
+
+<h5>Syntax:</h5>
+<pre>
+ declare float @llvm.fmuladd.f32(float %a, float %b, float %c)
+ declare double @llvm.fmuladd.f64(double %a, double %b, double %c)
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>llvm.fmuladd.*</tt>' intrinsic functions represent multiply-add
+expressions that can be fused if the code generator determines that the fused
+expression would be legal and efficient.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>llvm.fmuladd.*</tt>' intrinsics each take three arguments: two
+multiplicands, a and b, and an addend c.</p>
+
+<h5>Semantics:</h5>
+<p>The expression:</p>
+<pre>
+ %0 = call float @llvm.fmuladd.f32(%a, %b, %c)
+</pre>
+<p>is equivalent to the expression a * b + c, except that rounding will not be
+performed between the multiplication and addition steps if the code generator
+fuses the operations. Fusion is not guaranteed, even if the target platform
+supports it. If a fused multiply-add is required the corresponding llvm.fma.*
+intrinsic function should be used instead.</p>
+
+<h5>Examples:</h5>
+<pre>
+ %r2 = call float @llvm.fmuladd.f32(float %a, float %b, float %c) ; yields {float}:r2 = (a * b) + c
+</pre>
+
+</div>
+
<!-- ======================================================================= -->
<h3>
<a name="int_fp16">Half Precision Floating Point Intrinsics</a>
<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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