Analyze blocks with uses separately from live-through blocks without uses.
About 90% of the relevant blocks are live-through without uses, and the only
information required about them is their number. This saves memory and enables
later optimizations that need to look at only the use-blocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128985 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 238b566..201e9b1 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -48,7 +48,8 @@
void SplitAnalysis::clear() {
UseSlots.clear();
- LiveBlocks.clear();
+ UseBlocks.clear();
+ ThroughBlocks.clear();
CurLI = 0;
}
@@ -121,15 +122,17 @@
DEBUG(dbgs() << "*** Fixing inconsistent live interval! ***\n");
const_cast<LiveIntervals&>(LIS)
.shrinkToUses(const_cast<LiveInterval*>(CurLI));
- LiveBlocks.clear();
+ UseBlocks.clear();
+ ThroughBlocks.clear();
bool fixed = calcLiveBlockInfo();
(void)fixed;
assert(fixed && "Couldn't fix broken live interval");
}
DEBUG(dbgs() << "Analyze counted "
- << UseSlots.size() << " instrs, "
- << LiveBlocks.size() << " spanned.\n");
+ << UseSlots.size() << " instrs in "
+ << UseBlocks.size() << " blocks, through "
+ << ThroughBlocks.size() << " blocks.\n");
}
/// calcLiveBlockInfo - Fill the LiveBlocks array with information about blocks
@@ -159,8 +162,8 @@
BI.Def = LVI->start;
// Find the first and last uses in the block.
- BI.Uses = UseI != UseE && *UseI < Stop;
- if (BI.Uses) {
+ bool Uses = UseI != UseE && *UseI < Stop;
+ if (Uses) {
BI.FirstUse = *UseI;
assert(BI.FirstUse >= Start);
do ++UseI;
@@ -188,11 +191,14 @@
// Don't set LiveThrough when the block has a gap.
BI.LiveThrough = !hasGap && BI.LiveIn && BI.LiveOut;
- LiveBlocks.push_back(BI);
+ if (Uses)
+ UseBlocks.push_back(BI);
+ else
+ ThroughBlocks.push_back(BI.MBB->getNumber());
// FIXME: This should never happen. The live range stops or starts without a
// corresponding use. An earlier pass did something wrong.
- if (!BI.LiveThrough && !BI.Uses)
+ if (!BI.LiveThrough && !Uses)
return false;
// LVI is now at LVE or LVI->end >= Stop.
@@ -907,12 +913,12 @@
/// may be an advantage to split CurLI for the duration of the block.
bool SplitAnalysis::getMultiUseBlocks(BlockPtrSet &Blocks) {
// If CurLI is local to one block, there is no point to splitting it.
- if (LiveBlocks.size() <= 1)
+ if (UseBlocks.size() <= 1)
return false;
// Add blocks with multiple uses.
- for (unsigned i = 0, e = LiveBlocks.size(); i != e; ++i) {
- const BlockInfo &BI = LiveBlocks[i];
- if (!BI.Uses || BI.FirstUse == BI.LastUse)
+ for (unsigned i = 0, e = UseBlocks.size(); i != e; ++i) {
+ const BlockInfo &BI = UseBlocks[i];
+ if (BI.FirstUse == BI.LastUse)
continue;
Blocks.insert(BI.MBB);
}
@@ -923,10 +929,10 @@
/// basic block in Blocks.
void SplitEditor::splitSingleBlocks(const SplitAnalysis::BlockPtrSet &Blocks) {
DEBUG(dbgs() << " splitSingleBlocks for " << Blocks.size() << " blocks.\n");
-
- for (unsigned i = 0, e = SA.LiveBlocks.size(); i != e; ++i) {
- const SplitAnalysis::BlockInfo &BI = SA.LiveBlocks[i];
- if (!BI.Uses || !Blocks.count(BI.MBB))
+ ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA.getUseBlocks();
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
+ if (!Blocks.count(BI.MBB))
continue;
openIntv();