6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-28 04:33:05 +00:00
Code Issues Projects Releases Wiki Activity

Added description of invariant.load metadata to LangRef. It was added to the compiler in r144100

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150257 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Pete Cooper 2012-02-10 18:13:54 +00:00
parent 1de886c1fa
commit f95acc6d02
1 changed files with 9 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
docs/LangRef.html
View File

@ -4681,7 +4681,7 @@ IfUnequal:
<h5>Syntax:</h5>
<pre>
&lt;result&gt; = load [volatile] &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;][, !nontemporal !&lt;index&gt;]
&lt;result&gt; = load [volatile] &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;][, !nontemporal !&lt;index&gt;][, !invariant.load !&lt;index&gt;]
&lt;result&gt; = load atomic [volatile] &lt;ty&gt;* &lt;pointer&gt; [singlethread] &lt;ordering&gt;, align &lt;alignment&gt;
!&lt;index&gt; = !{ i32 1 }
</pre>
@ -4726,6 +4726,14 @@ IfUnequal:
The code generator may select special instructions to save cache bandwidth,
such as the <tt>MOVNT</tt> instruction on x86.</p>
<p>The optional <tt>!invariant.load</tt> metadata must reference a single
metatadata name &lt;index&gt; corresponding to a metadata node with no
entries. The existence of the <tt>!invariant.load</tt> metatadata on the
instruction tells the optimizer and code generator that this load address
points to memory which does not change value during program execution.
The optimizer may then move this load around, for example, by hoisting it
out of loops using loop invariant code motion.</p>
<h5>Semantics:</h5>
<p>The location of memory pointed to is loaded. If the value being loaded is of
scalar type then the number of bytes read does not exceed the minimum number