Revert "Remove unnecessary null check. NFC."

[oota-llvm.git] / lib / CodeGen / LiveRangeCalc.cpp

diff --git a/lib/CodeGen/LiveRangeCalc.cpp b/lib/CodeGen/LiveRangeCalc.cpp
index d804b39c59775ed302ff43ea3068611da67b0415..bb2877ae31a89f9026d7664c9eb3fb633b84ad7c 100644 (file)
--- a/lib/CodeGen/LiveRangeCalc.cpp
+++ b/lib/CodeGen/LiveRangeCalc.cpp
@@ -50,7 +50,7 @@ static void createDeadDef(SlotIndexes &Indexes, VNInfo::Allocator &Alloc,
     LR.createDeadDef(DefIdx, Alloc);
 }
 
-void LiveRangeCalc::calculate(LiveInterval &LI) {
+void LiveRangeCalc::calculate(LiveInterval &LI, bool TrackSubRegs) {
   assert(MRI && Indexes && "call reset() first");
 
   // Step 1: Create minimal live segments for every definition of Reg.
@@ -63,7 +63,7 @@ void LiveRangeCalc::calculate(LiveInterval &LI) {
       continue;
 
     unsigned SubReg = MO.getSubReg();
-    if (LI.hasSubRanges() || (SubReg != 0 && MRI->tracksSubRegLiveness())) {
+    if (LI.hasSubRanges() || (SubReg != 0 && TrackSubRegs)) {
       unsigned Mask = SubReg != 0 ? TRI.getSubRegIndexLaneMask(SubReg)
                                   : MRI->getMaxLaneMaskForVReg(Reg);
 
@@ -272,13 +272,19 @@ bool LiveRangeCalc::findReachingDefs(LiveRange &LR, MachineBasicBlock &UseMBB,
 #ifndef NDEBUG
     if (MBB->pred_empty()) {
       MBB->getParent()->verify();
+      errs() << "Use of " << PrintReg(PhysReg)
+             << " does not have a corresponding definition on every path:\n";
+      const MachineInstr *MI = Indexes->getInstructionFromIndex(Use);
+      if (MI != nullptr)
+        errs() << Use << " " << *MI;
       llvm_unreachable("Use not jointly dominated by defs.");
     }
 
     if (TargetRegisterInfo::isPhysicalRegister(PhysReg) &&
         !MBB->isLiveIn(PhysReg)) {
       MBB->getParent()->verify();
-      errs() << "The register needs to be live in to BB#" << MBB->getNumber()
+      errs() << "The register " << PrintReg(PhysReg)
+             << " needs to be live in to BB#" << MBB->getNumber()
              << ", but is missing from the live-in list.\n";
       llvm_unreachable("Invalid global physical register");
     }