Verify LiveIntervals against the CFG, ensuring that live-in values are live-out

of all predecessors.

llvm-svn: 117191
This commit is contained in:
Jakob Stoklund Olesen 2010-10-23 00:49:09 +00:00
parent 1e091f8c58
commit 964f6a6be6

View File

@ -946,7 +946,8 @@ void MachineVerifier::verifyLiveIntervals() {
const MachineInstr *MI = LiveInts->getInstructionFromIndex(VNI->def);
if (!MI) {
report("No instruction at def index", MF);
*OS << "Valno #" << VNI->id << " is defined at " << VNI->def << '\n';
*OS << "Valno #" << VNI->id << " is defined at " << VNI->def
<< " in " << LI << '\n';
} else if (!MI->modifiesRegister(LI.reg, TRI)) {
report("Defining instruction does not modify register", MI);
*OS << "Valno #" << VNI->id << " in " << LI << '\n';
@ -970,6 +971,81 @@ void MachineVerifier::verifyLiveIntervals() {
*OS << " in " << LI << '\n';
}
const MachineBasicBlock *MBB = LiveInts->getMBBFromIndex(I->start);
if (!MBB) {
report("Bad start of live segment, no basic block", MF);
I->print(*OS);
*OS << " in " << LI << '\n';
continue;
}
SlotIndex MBBStartIdx = LiveInts->getMBBStartIdx(MBB);
if (I->start != MBBStartIdx && I->start != VNI->def) {
report("Live segment must begin at MBB entry or valno def", MBB);
I->print(*OS);
*OS << " in " << LI << '\n' << "Basic block starts at "
<< MBBStartIdx << '\n';
}
const MachineBasicBlock *EndMBB =
LiveInts->getMBBFromIndex(I->end.getPrevSlot());
if (!EndMBB) {
report("Bad end of live segment, no basic block", MF);
I->print(*OS);
*OS << " in " << LI << '\n';
continue;
}
if (I->end != LiveInts->getMBBEndIdx(EndMBB)) {
// The live segment is ending inside EndMBB
const MachineInstr *MI =
LiveInts->getInstructionFromIndex(I->end.getPrevSlot());
if (!MI) {
report("Live segment doesn't end at a valid instruction", EndMBB);
I->print(*OS);
*OS << " in " << LI << '\n' << "Basic block starts at "
<< MBBStartIdx << '\n';
} else if (TargetRegisterInfo::isVirtualRegister(LI.reg) &&
!MI->readsVirtualRegister(LI.reg)) {
// FIXME: Should we require a kill flag?
report("Instruction killing live segment doesn't read register", MI);
I->print(*OS);
*OS << " in " << LI << '\n';
}
}
// Now check all the basic blocks in this live segment.
MachineFunction::const_iterator MFI = MBB;
// Is LI live-in to MBB and not a PHIDef?
if (I->start == VNI->def) {
// Not live-in to any blocks.
if (MBB == EndMBB)
continue;
// Skip this block.
++MFI;
}
for (;;) {
assert(LiveInts->isLiveInToMBB(LI, MFI));
// Check that VNI is live-out of all predecessors.
for (MachineBasicBlock::const_pred_iterator PI = MFI->pred_begin(),
PE = MFI->pred_end(); PI != PE; ++PI) {
SlotIndex PEnd = LiveInts->getMBBEndIdx(*PI).getPrevSlot();
const VNInfo *PVNI = LI.getVNInfoAt(PEnd);
if (!PVNI) {
report("Register not marked live out of predecessor", *PI);
*OS << "Valno #" << VNI->id << " live into BB#" << MFI->getNumber()
<< '@' << LiveInts->getMBBStartIdx(MFI) << ", not live at "
<< PEnd << " in " << LI << '\n';
} else if (PVNI != VNI) {
report("Different value live out of predecessor", *PI);
*OS << "Valno #" << PVNI->id << " live out of BB#"
<< (*PI)->getNumber() << '@' << PEnd
<< "\nValno #" << VNI->id << " live into BB#" << MFI->getNumber()
<< '@' << LiveInts->getMBBStartIdx(MFI) << " in " << LI << '\n';
}
}
if (&*MFI == EndMBB)
break;
++MFI;
}
}
}
}