commit 66446c803a11a26e4bb39b74091d146ac850ae4c
author Jakob Stoklund Olesen <stoklund@2pi.dk> Sat Apr 30 05:07:46 2011 +0000
committer Jakob Stoklund Olesen <stoklund@2pi.dk> Sat Apr 30 05:07:46 2011 +0000
tree 1b58844cb68fd77e37a94d852097d91c3d50aa50
parent 4f5558e676b8c34d5094681d2797367682f96918

Use hysteresis for local live range splitting as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130596 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/RegAllocGreedy.cpp

diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp
index d57bc88..7c461d8 100644
--- a/lib/CodeGen/RegAllocGreedy.cpp
+++ b/lib/CodeGen/RegAllocGreedy.cpp
@@ -1225,13 +1225,13 @@
                               PrevSlot[SplitBefore].distance(Uses[SplitAfter]));
         // Would this split be possible to allocate?
         // Never allocate all gaps, we wouldn't be making progress.
-        float Diff = EstWeight - MaxGap;
-        DEBUG(dbgs() << " w=" << EstWeight << " d=" << Diff);
-        if (Diff > 0) {
+        DEBUG(dbgs() << " w=" << EstWeight);
+        if (EstWeight * Hysteresis >= MaxGap) {
           Shrink = false;
+          float Diff = EstWeight - MaxGap;
           if (Diff > BestDiff) {
             DEBUG(dbgs() << " (best)");
-            BestDiff = Diff;
+            BestDiff = Hysteresis * Diff;
             BestBefore = SplitBefore;
             BestAfter = SplitAfter;
           }