Teach AnalyzeBranch, RemoveBranch and the branch
folder to be tolerant of debug info following the
branch(es) at the end of a block.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100168 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Alpha/AlphaInstrInfo.cpp b/lib/Target/Alpha/AlphaInstrInfo.cpp
index 39f0749..d539e08 100644
--- a/lib/Target/Alpha/AlphaInstrInfo.cpp
+++ b/lib/Target/Alpha/AlphaInstrInfo.cpp
@@ -301,7 +301,15 @@
                                    bool AllowModify) const {
   // If the block has no terminators, it just falls into the block after it.
   MachineBasicBlock::iterator I = MBB.end();
-  if (I == MBB.begin() || !isUnpredicatedTerminator(--I))
+  if (I == MBB.begin())
+    return false;
+  --I;
+  while (I->isDebugValue()) {
+    if (I == MBB.begin())
+      return false;
+    --I;
+  }
+  if (!isUnpredicatedTerminator(I))
     return false;
 
   // Get the last instruction in the block.
@@ -362,6 +370,11 @@
   MachineBasicBlock::iterator I = MBB.end();
   if (I == MBB.begin()) return 0;
   --I;
+  while (I->isDebugValue()) {
+    if (I == MBB.begin())
+      return 0;
+    --I;
+  }
   if (I->getOpcode() != Alpha::BR && 
       I->getOpcode() != Alpha::COND_BRANCH_I &&
       I->getOpcode() != Alpha::COND_BRANCH_F)