commit 35bda8914c0d1c02a6f90f42e7810c83150737e1
author Chris Lattner <sabre@nondot.org> Sun Feb 06 21:44:57 2011 +0000
committer Chris Lattner <sabre@nondot.org> Sun Feb 06 21:44:57 2011 +0000
tree b210ccd009a7ac5331c76c6393b5b45d141d12d0
parent bd75021465e7f8c81785e692cfd3ce559764e46f

enhance vmcore to know that udiv's can be exact, and add a trivial
instcombine xform to exercise this.

Nothing forms exact udivs yet though.  This is progress on PR8862



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124992 91177308-0d34-0410-b5e6-96231b3b80d8

docs/LangRef.html

diff --git a/docs/LangRef.html b/docs/LangRef.html
index da365ff..f799749 100644
--- a/docs/LangRef.html
+++ b/docs/LangRef.html
@@ -3441,7 +3441,8 @@
 
 <h5>Syntax:</h5>
 <pre>
-  &lt;result&gt; = udiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt;   <i>; yields {ty}:result</i>
+  &lt;result&gt; = udiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt;         <i>; yields {ty}:result</i>
+  &lt;result&gt; = udiv exact &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt;   <i>; yields {ty}:result</i>
 </pre>
 
 <h5>Overview:</h5>
@@ -3460,6 +3461,11 @@
 
 <p>Division by zero leads to undefined behavior.</p>
 
+<p>If the <tt>exact</tt> keyword is present, the result value of the
+   <tt>udiv</tt> is a <a href="#trapvalues">trap value</a> if %op1 is not a
+  multiple of %op2 (as such, "((a udiv exact b) mul b) == a").</p>
+
+
 <h5>Example:</h5>
 <pre>
   &lt;result&gt; = udiv i32 4, %var          <i>; yields {i32}:result = 4 / %var</i>