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Use hysteresis for local live range splitting as well.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130596 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2011-04-30 05:07:46 +00:00
parent 4f5558e676
commit 66446c803a
1 changed files with 4 additions and 4 deletions
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8
lib/CodeGen/RegAllocGreedy.cpp
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@ -1225,13 +1225,13 @@ unsigned RAGreedy::tryLocalSplit(LiveInterval &VirtReg, AllocationOrder &Order,
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;
}