<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<p>Hi Aditya,</p>
<p>My name is Gabor Ballabas, I work at the University of Szeged,
Hungary.<br>
</p>
<p>We are running a code-size change benchmark system at <a
href="www.csibe.org">www.csibe.org</a></p>
I'd like to share with you - and with the community - the code-size
change<br>
results in our benchmark system after your patch landed.<br>
We run this benchmarks after every commit in LLVM.<br>
<p>Your patch resulted in the following improvements in code size:</p>
* Target: x86_64, -Oz: -0.136%<br>
* Target: ARM, Cortex-M0, -Oz: -0.061%<br>
* Target: ARM, Cortex-M4, -Oz: -0.211%<br>
<br>
You can check the charts here: <a
href="http://szeged.github.io/csibe/compiler-monitor.html">http://szeged.github.io/csibe/compiler-monitor.html</a><br>
<br>
I hope you will find this feedback useful.<br>
<br>
Best regards,<br>
Gabor Ballabas<br>
<p><a href="www.csibe.org"><br>
</a></p>
<p><a href="www.csibe.org"><br>
</a></p>
<div class="moz-cite-prefix">On 11/29/2016 03:34 PM, Aditya Kumar
via llvm-commits wrote:<br>
</div>
<blockquote cite="mid:20161129143402.5F5602A6C076@llvm.org"
type="cite">
<pre wrap="">Author: hiraditya
Date: Tue Nov 29 08:34:01 2016
New Revision: 288141
URL: <a class="moz-txt-link-freetext" href="http://llvm.org/viewvc/llvm-project?rev=288141&view=rev">http://llvm.org/viewvc/llvm-project?rev=288141&view=rev</a>
Log:
[GVNHoist] Enable aggressive hoisting when optimizing for code-size
Enable scalar hoisting at -Oz as it is safe to hoist scalars to a place
where they are partially needed.
Differential Revision: <a class="moz-txt-link-freetext" href="https://reviews.llvm.org/D27111">https://reviews.llvm.org/D27111</a>
Modified:
llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp
URL: <a class="moz-txt-link-freetext" href="http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp?rev=288141&r1=288140&r2=288141&view=diff">http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp?rev=288141&r1=288140&r2=288141&view=diff</a>
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp Tue Nov 29 08:34:01 2016
@@ -202,7 +202,12 @@ public:
GVNHoist(DominatorTree *DT, AliasAnalysis *AA, MemoryDependenceResults *MD,
MemorySSA *MSSA, bool OptForMinSize)
: DT(DT), AA(AA), MD(MD), MSSA(MSSA), OptForMinSize(OptForMinSize),
- HoistingGeps(OptForMinSize), HoistedCtr(0) {}
+ HoistingGeps(OptForMinSize), HoistedCtr(0) {
+ // Hoist as far as possible when optimizing for code-size.
+ if (OptForMinSize)
+ MaxNumberOfBBSInPath = -1;
+ }
+
bool run(Function &F) {
VN.setDomTree(DT);
VN.setAliasAnalysis(AA);
@@ -500,10 +505,13 @@ private:
bool safeToHoistScalar(const BasicBlock *HoistBB,
SmallPtrSetImpl<const BasicBlock *> &WL,
int &NBBsOnAllPaths) {
- // Check that the hoisted expression is needed on all paths. Enable scalar
- // hoisting at -Oz as it is safe to hoist scalars to a place where they are
- // partially needed.
- if (!OptForMinSize && !hoistingFromAllPaths(HoistBB, WL))
+ // Enable scalar hoisting at -Oz as it is safe to hoist scalars to a place
+ // where they are partially needed.
+ if (OptForMinSize)
+ return true;
+
+ // Check that the hoisted expression is needed on all paths.
+ if (!hoistingFromAllPaths(HoistBB, WL))
return false;
for (const BasicBlock *BB : WL)
_______________________________________________
llvm-commits mailing list
<a class="moz-txt-link-abbreviated" href="mailto:llvm-commits@lists.llvm.org">llvm-commits@lists.llvm.org</a>
<a class="moz-txt-link-freetext" href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits</a>
</pre>
</blockquote>
<br>
</body>
</html>