Rewrite the SDep class, and simplify some of the related code.

The Cost field is removed. It was only being used in a very limited way,
to indicate when the scheduler should attempt to protect a live register,
and it isn't really needed to do that. If we ever want the scheduler to
start inserting copies in non-prohibitive situations, we'll have to
rethink some things anyway.

A Latency field is added. Instead of giving each node a single
fixed latency, each edge can have its own latency. This will eventually
be used to model various micro-architecture properties more accurately.

The PointerIntPair class and an internal union are now used, which
reduce the overall size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60806 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2008-12-09 22:54:47 +00:00
parent 5a45bf1b48
commit 54e4c36a73
12 changed files with 526 additions and 376 deletions

View File

@ -40,31 +40,31 @@ void ScheduleDAG::EmitCrossRCCopy(SUnit *SU,
DenseMap<SUnit*, unsigned> &VRBaseMap) {
for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I) {
if (I->isCtrl) continue; // ignore chain preds
if (I->Dep->CopyDstRC) {
if (I->isCtrl()) continue; // ignore chain preds
if (I->getSUnit()->CopyDstRC) {
// Copy to physical register.
DenseMap<SUnit*, unsigned>::iterator VRI = VRBaseMap.find(I->Dep);
DenseMap<SUnit*, unsigned>::iterator VRI = VRBaseMap.find(I->getSUnit());
assert(VRI != VRBaseMap.end() && "Node emitted out of order - late");
// Find the destination physical register.
unsigned Reg = 0;
for (SUnit::const_succ_iterator II = SU->Succs.begin(),
EE = SU->Succs.end(); II != EE; ++II) {
if (I->Reg) {
Reg = I->Reg;
if (I->getReg()) {
Reg = I->getReg();
break;
}
}
assert(I->Reg && "Unknown physical register!");
assert(I->getReg() && "Unknown physical register!");
TII->copyRegToReg(*BB, BB->end(), Reg, VRI->second,
SU->CopyDstRC, SU->CopySrcRC);
} else {
// Copy from physical register.
assert(I->Reg && "Unknown physical register!");
assert(I->getReg() && "Unknown physical register!");
unsigned VRBase = MRI.createVirtualRegister(SU->CopyDstRC);
bool isNew = VRBaseMap.insert(std::make_pair(SU, VRBase)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
TII->copyRegToReg(*BB, BB->end(), VRBase, I->Reg,
TII->copyRegToReg(*BB, BB->end(), VRBase, I->getReg(),
SU->CopyDstRC, SU->CopySrcRC);
}
break;