[Statepoint Lowering] Update misleading comments about chains

llvm-svn: 353800
This commit is contained in:
Philip Reames 2019-02-12 06:25:58 +00:00
parent 0686d1ae41
commit b6dc6eb8bb
1 changed files with 7 additions and 9 deletions

View File

@ -366,10 +366,6 @@ spillIncomingStatepointValue(SDValue Incoming, SDValue Chain,
// We use TargetFrameIndex so that isel will not select it into LEA
Loc = Builder.DAG.getTargetFrameIndex(Index, Builder.getFrameIndexTy());
// TODO: We can create TokenFactor node instead of
// chaining stores one after another, this may allow
// a bit more optimal scheduling for them
#ifndef NDEBUG
// Right now we always allocate spill slots that are of the same
// size as the value we're about to spill (the size of spillee can
@ -398,6 +394,9 @@ spillIncomingStatepointValue(SDValue Incoming, SDValue Chain,
static void lowerIncomingStatepointValue(SDValue Incoming, bool LiveInOnly,
SmallVectorImpl<SDValue> &Ops,
SelectionDAGBuilder &Builder) {
// Note: We know all of these spills are independent, but don't bother to
// exploit that chain wise. DAGCombine will happily do so as needed, so
// doing it here would be a small compile time win at most.
SDValue Chain = Builder.getRoot();
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Incoming)) {
@ -984,11 +983,11 @@ void SelectionDAGBuilder::visitGCRelocate(const GCRelocateInst &Relocate) {
}
SDValue SpillSlot =
DAG.getTargetFrameIndex(*DerivedPtrLocation, getFrameIndexTy());
DAG.getTargetFrameIndex(*DerivedPtrLocation, getFrameIndexTy());
// Be conservative: flush all pending loads
// TODO: Probably we can be less restrictive on this,
// it may allow more scheduling opportunities.
// Note: We know all of these reloads are independent, but don't bother to
// exploit that chain wise. DAGCombine will happily do so as needed, so
// doing it here would be a small compile time win at most.
SDValue Chain = getRoot();
SDValue SpillLoad =
@ -998,7 +997,6 @@ void SelectionDAGBuilder::visitGCRelocate(const GCRelocateInst &Relocate) {
MachinePointerInfo::getFixedStack(DAG.getMachineFunction(),
*DerivedPtrLocation));
// Again, be conservative, don't emit pending loads
DAG.setRoot(SpillLoad.getValue(1));
assert(SpillLoad.getNode());