move isOnlyReachableByFallthrough out of MachineBasicBlock into AsmPrinter,

and add a sparc implementation that knows about delay slots.  Patch by
Nathan Keynes!

llvm-svn: 96492

1 files changed, 0 insertions, 30 deletions

diff --git a/llvm/lib/CodeGen/MachineBasicBlock.cpp b/llvm/lib/CodeGen/MachineBasicBlock.cpp
index 655a0bf4450..64134ce59e9 100644
--- a/llvm/lib/CodeGen/MachineBasicBlock.cpp
+++ b/llvm/lib/CodeGen/MachineBasicBlock.cpp
@@ -143,36 +143,6 @@ MachineBasicBlock::iterator MachineBasicBlock::getFirstTerminator() {
   return I;
 }
 
-/// isOnlyReachableViaFallthough - Return true if this basic block has
-/// exactly one predecessor and the control transfer mechanism between
-/// the predecessor and this block is a fall-through.
-bool MachineBasicBlock::isOnlyReachableByFallthrough() const {
-  // If this is a landing pad, it isn't a fall through.  If it has no preds,
-  // then nothing falls through to it.
-  if (isLandingPad() || pred_empty())
-    return false;
-  
-  // If there isn't exactly one predecessor, it can't be a fall through.
-  const_pred_iterator PI = pred_begin(), PI2 = PI;
-  ++PI2;
-  if (PI2 != pred_end())
-    return false;
-  
-  // The predecessor has to be immediately before this block.
-  const MachineBasicBlock *Pred = *PI;
-  
-  if (!Pred->isLayoutSuccessor(this))
-    return false;
-  
-  // If the block is completely empty, then it definitely does fall through.
-  if (Pred->empty())
-    return true;
-  
-  // Otherwise, check the last instruction.
-  const MachineInstr &LastInst = Pred->back();
-  return !LastInst.getDesc().isBarrier();
-}
-
 void MachineBasicBlock::dump() const {
   print(dbgs());
 }