Move PHIElimination::isLiveOut method to LiveVariables.

We want LiveVariables clients to use methods rather than accessing the
getVarInfo data structure directly. That way it will be possible to change the
LiveVariables representation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90240 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 48 deletions

diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index 2e30cc6abd..68a1c240c8 100644
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -287,7 +287,7 @@ void llvm::PHIElimination::LowerAtomicPHINode(
 
     // Okay, if we now know that the value is not live out of the block, we can
     // add a kill marker in this block saying that it kills the incoming value!
-    if (!ValueIsUsed && !isLiveOut(SrcReg, opBlock, *LV)) {
+    if (!ValueIsUsed && !LV->isLiveOut(SrcReg, opBlock)) {
       // In our final twist, we have to decide which instruction kills the
       // register.  In most cases this is the copy, however, the first
       // terminator instruction at the end of the block may also use the value.
@@ -353,59 +353,13 @@ bool llvm::PHIElimination::SplitPHIEdges(MachineFunction &MF,
       // We break edges when registers are live out from the predecessor block
       // (not considering PHI nodes). If the register is live in to this block
       // anyway, we would gain nothing from splitting.
-      if (!LV.isLiveIn(Reg, MBB) && isLiveOut(Reg, *PreMBB, LV))
+      if (!LV.isLiveIn(Reg, MBB) && LV.isLiveOut(Reg, *PreMBB))
         SplitCriticalEdge(PreMBB, &MBB);
     }
   }
   return true;
 }
 
-bool llvm::PHIElimination::isLiveOut(unsigned Reg, const MachineBasicBlock &MBB,
-                                     LiveVariables &LV) {
-  LiveVariables::VarInfo &VI = LV.getVarInfo(Reg);
-
-  // Loop over all of the successors of the basic block, checking to see if
-  // the value is either live in the block, or if it is killed in the block.
-  std::vector<MachineBasicBlock*> OpSuccBlocks;
-  for (MachineBasicBlock::const_succ_iterator SI = MBB.succ_begin(),
-         E = MBB.succ_end(); SI != E; ++SI) {
-    MachineBasicBlock *SuccMBB = *SI;
-
-    // Is it alive in this successor?
-    unsigned SuccIdx = SuccMBB->getNumber();
-    if (VI.AliveBlocks.test(SuccIdx))
-      return true;
-    OpSuccBlocks.push_back(SuccMBB);
-  }
-
-  // Check to see if this value is live because there is a use in a successor
-  // that kills it.
-  switch (OpSuccBlocks.size()) {
-  case 1: {
-    MachineBasicBlock *SuccMBB = OpSuccBlocks[0];
-    for (unsigned i = 0, e = VI.Kills.size(); i != e; ++i)
-      if (VI.Kills[i]->getParent() == SuccMBB)
-        return true;
-    break;
-  }
-  case 2: {
-    MachineBasicBlock *SuccMBB1 = OpSuccBlocks[0], *SuccMBB2 = OpSuccBlocks[1];
-    for (unsigned i = 0, e = VI.Kills.size(); i != e; ++i)
-      if (VI.Kills[i]->getParent() == SuccMBB1 ||
-          VI.Kills[i]->getParent() == SuccMBB2)
-        return true;
-    break;
-  }
-  default:
-    std::sort(OpSuccBlocks.begin(), OpSuccBlocks.end());
-    for (unsigned i = 0, e = VI.Kills.size(); i != e; ++i)
-      if (std::binary_search(OpSuccBlocks.begin(), OpSuccBlocks.end(),
-                             VI.Kills[i]->getParent()))
-        return true;
-  }
-  return false;
-}
-
 MachineBasicBlock *PHIElimination::SplitCriticalEdge(MachineBasicBlock *A,
                                                      MachineBasicBlock *B) {
   assert(A && B && "Missing MBB end point");