LiveVariables::VarInfo contains an AliveBlocks BitVector, which has as many
entries as there are basic blocks in the function. LiveVariables::getVarInfo
creates a VarInfo struct for every register in the function, leading to
quadratic space use. This patch changes the BitVector to a SparseBitVector,
which doesn't help the worst-case memory use but does reduce the actual use in
very long functions with short-lived variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72426 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 612b9ac..bf18015 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -422,7 +422,7 @@
// If the kill happens after the definition, we have an intra-block
// live range.
if (killIdx > defIndex) {
- assert(vi.AliveBlocks.none() &&
+ assert(vi.AliveBlocks.empty() &&
"Shouldn't be alive across any blocks!");
LiveRange LR(defIndex, killIdx, ValNo);
interval.addRange(LR);
@@ -443,10 +443,10 @@
// Iterate over all of the blocks that the variable is completely
// live in, adding [insrtIndex(begin), instrIndex(end)+4) to the
// live interval.
- for (int i = vi.AliveBlocks.find_first(); i != -1;
- i = vi.AliveBlocks.find_next(i)) {
- LiveRange LR(getMBBStartIdx(i),
- getMBBEndIdx(i)+1, // MBB ends at -1.
+ for (SparseBitVector<>::iterator I = vi.AliveBlocks.begin(),
+ E = vi.AliveBlocks.end(); I != E; ++I) {
+ LiveRange LR(getMBBStartIdx(*I),
+ getMBBEndIdx(*I)+1, // MBB ends at -1.
ValNo);
interval.addRange(LR);
DOUT << " +" << LR;