6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2026-04-20 00:20:11 +00:00
Code Issues Projects Releases Wiki Activity

Cache basic block bounds instead of asking SlotIndexes::getMBBRange all the time.

Browse Source 
This speeds up the greedy register allocator by 15%.
DenseMap is not as fast as one might hope.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126921 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen
2011-03-03 03:41:29 +00:00
parent f27a40a971
commit 36d61863bc
3 changed files with 42 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/CodeGen/SplitKit.cpp
+10 -11
View File
@@ -105,8 +105,7 @@ void SplitAnalysis::calcLiveBlockInfo() {
for (;;) {
BlockInfo BI;
BI.MBB = MFI;
SlotIndex Start, Stop;
tie(Start, Stop) = LIS.getSlotIndexes()->getMBBRange(BI.MBB);
tie(BI.Start, BI.Stop) = LIS.getSlotIndexes()->getMBBRange(BI.MBB);
// The last split point is the latest possible insertion point that dominates
// all successor blocks. If interference reaches LastSplitPoint, it is not
@@ -114,12 +113,12 @@ void SplitAnalysis::calcLiveBlockInfo() {
// outgoing bundle.
MachineBasicBlock::iterator LSP = LIS.getLastSplitPoint(*CurLI, BI.MBB);
if (LSP == BI.MBB->end())
BI.LastSplitPoint = Stop;
BI.LastSplitPoint = BI.Stop;
else
BI.LastSplitPoint = LIS.getInstructionIndex(LSP);
// LVI is the first live segment overlapping MBB.
BI.LiveIn = LVI->start <= Start;
BI.LiveIn = LVI->start <= BI.Start;
if (!BI.LiveIn)
BI.Def = LVI->start;
@@ -127,19 +126,19 @@ void SplitAnalysis::calcLiveBlockInfo() {
BI.Uses = hasUses(MFI);
if (BI.Uses && UseI != UseE) {
BI.FirstUse = *UseI;
assert(BI.FirstUse >= Start);
assert(BI.FirstUse >= BI.Start);
do ++UseI;
while (UseI != UseE && *UseI < Stop);
while (UseI != UseE && *UseI < BI.Stop);
BI.LastUse = UseI[-1];
assert(BI.LastUse < Stop);
assert(BI.LastUse < BI.Stop);
}
// Look for gaps in the live range.
bool hasGap = false;
BI.LiveOut = true;
while (LVI->end < Stop) {
while (LVI->end < BI.Stop) {
SlotIndex LastStop = LVI->end;
if (++LVI == LVE || LVI->start >= Stop) {
if (++LVI == LVE || LVI->start >= BI.Stop) {
BI.Kill = LastStop;
BI.LiveOut = false;
break;
@@ -160,11 +159,11 @@ void SplitAnalysis::calcLiveBlockInfo() {
break;
// Live segment ends exactly at Stop. Move to the next segment.
if (LVI->end == Stop && ++LVI == LVE)
if (LVI->end == BI.Stop && ++LVI == LVE)
break;
// Pick the next basic block.
if (LVI->start < Stop)
if (LVI->start < BI.Stop)
++MFI;
else
MFI = LIS.getMBBFromIndex(LVI->start);