Fast-math flags documentation added to LangRef

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168652 91177308-0d34-0410-b5e6-96231b3b80d8
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Michael Ilseman 2012-11-27 00:48:29 +00:00
parent cb84142195
commit a33e3d75fe

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@ -3970,7 +3970,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = fadd &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
&lt;result&gt; = fadd [fast-math flags]* &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
@ -3982,7 +3982,28 @@ IfUnequal:
floating point values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point sum of the two operands.</p>
<p>The value produced is the floating point sum of the two operands. This
instruction can also take any number of fast-math flags, which are
optimization hints to enable otherwise unsafe floating point
optimizations:</p>
<ol>
<li><tt>nnan</tt>: No NaNs - Allow optimizations to assume the arguments and
result are not NaN. Such optimizations are required to retain defined behavior
over NaNs, but the value of the result is undefined.</li>
<li><tt>ninf</tt>: No Inf - Allow optimizations to assume the arguments and
result are not +/-Inf. Such optimizations are required to retain defined
behavior over +/-Inf, but the value of the result is undefined.</li>
<li><tt>nsz</tt>: No Signed Zeros: Allow optimizations to treat the
sign of a zero argument or result as insignificant. </li>
<li><tt>fast</tt>: Allow algebraically equivalent transformations that may
dramatically change results in floating point (e.g. reassociate). This flag
implies all the others.</li>
</ol>
<h5>Example:</h5>
<pre>
@ -4052,7 +4073,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = fsub &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
&lt;result&gt; = fsub [fast-math flags]* &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
@ -4069,7 +4090,28 @@ IfUnequal:
floating point values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point difference of the two operands.</p>
<p>The value produced is the floating point difference of the two operands. This
instruction can also take any number of fast-math flags, which are
optimization hints to enable otherwise unsafe floating point
optimizations:</p>
<ol>
<li><tt>nnan</tt>: No NaNs - Allow optimizations to assume the arguments and
result are not NaN. Such optimizations are required to retain defined behavior
over NaNs, but the value of the result is undefined.</li>
<li><tt>ninf</tt>: No Inf - Allow optimizations to assume the arguments and
result are not +/-Inf. Such optimizations are required to retain defined
behavior over +/-Inf, but the value of the result is undefined.</li>
<li><tt>nsz</tt>: No Signed Zeros: Allow optimizations to treat the
sign of a zero argument or result as insignificant. </li>
<li><tt>fast</tt>: Allow algebraically equivalent transformations that may
dramatically change results in floating point (e.g. reassociate). This flag
implies all the others.</li>
</ol>
<h5>Example:</h5>
<pre>
@ -4138,7 +4180,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = fmul &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
&lt;result&gt; = fmul [fast-math flags]* &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
@ -4150,7 +4192,28 @@ IfUnequal:
floating point values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point product of the two operands.</p>
<p>The value produced is the floating point product of the two operands. This
instruction can also take any number of fast-math flags, which are
optimization hints to enable otherwise unsafe floating point
optimizations:</p>
<ol>
<li><tt>nnan</tt>: No NaNs - Allow optimizations to assume the arguments and
result are not NaN. Such optimizations are required to retain defined behavior
over NaNs, but the value of the result is undefined.</li>
<li><tt>ninf</tt>: No Inf - Allow optimizations to assume the arguments and
result are not +/-Inf. Such optimizations are required to retain defined
behavior over +/-Inf, but the value of the result is undefined.</li>
<li><tt>nsz</tt>: No Signed Zeros: Allow optimizations to treat the
sign of a zero argument or result as insignificant. </li>
<li><tt>fast</tt>: Allow algebraically equivalent transformations that may
dramatically change results in floating point (e.g. reassociate). This flag
implies all the others.</li>
</ol>
<h5>Example:</h5>
<pre>
@ -4252,7 +4315,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = fdiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
&lt;result&gt; = fdiv [fast-math flags]* &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
@ -4264,7 +4327,32 @@ IfUnequal:
floating point values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point quotient of the two operands.</p>
<p>The value produced is the floating point quotient of the two operands. This
instruction can also take any number of fast-math flags, which are
optimization hints to enable otherwise unsafe floating point
optimizations:</p>
<ol>
<li><tt>nnan</tt>: No NaNs - Allow optimizations to assume the arguments and
result are not NaN. Such optimizations are required to retain defined behavior
over NaNs, but the value of the result is undefined.</li>
<li><tt>ninf</tt>: No Inf - Allow optimizations to assume the arguments and
result are not +/-Inf. Such optimizations are required to retain defined
behavior over +/-Inf, but the value of the result is undefined.</li>
<li><tt>nsz</tt>: No Signed Zeros: Allow optimizations to treat the
sign of a zero argument or result as insignificant. </li>
<li><tt>arcp</tt>: Allow Reciprocal: Allow optimizations to use the reciprocal
of an argument rather than perform division. </li>
<li><tt>fast</tt>: Allow algebraically equivalent transformations that may
dramatically change results in floating point (e.g. reassociate). This flag
implies all the others.</li>
</ol>
</p>
<h5>Example:</h5>
<pre>
@ -4371,7 +4459,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = frem &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
&lt;result&gt; = frem [fast-math flags]* &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
@ -4384,8 +4472,32 @@ IfUnequal:
floating point values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>This instruction returns the <i>remainder</i> of a division. The remainder
has the same sign as the dividend.</p>
<p>This instruction returns the <i>remainder</i> of a division. The remainder
has the same sign as the dividend. This instruction can also take any number
of fast-math flags, which are optimization hints to enable otherwise unsafe
floating point optimizations:</p>
<ol>
<li><tt>nnan</tt>: No NaNs - Allow optimizations to assume the arguments and
result are not NaN. Such optimizations are required to retain defined behavior
over NaNs, but the value of the result is undefined.</li>
<li><tt>ninf</tt>: No Inf - Allow optimizations to assume the arguments and
result are not +/-Inf. Such optimizations are required to retain defined
behavior over +/-Inf, but the value of the result is undefined.</li>
<li><tt>nsz</tt>: No Signed Zeros: Allow optimizations to treat the
sign of a zero argument or result as insignificant. </li>
<li><tt>arcp</tt>: Allow Reciprocal: Allow optimizations to use the reciprocal
of an argument rather than perform division. </li>
<li><tt>fast</tt>: Allow algebraically equivalent transformations that may
dramatically change results in floating point (e.g. reassociate). This flag
implies all the others.</li>
</ol>
<h5>Example:</h5>
<pre>