Ignore dbg intrinsics while propagating conditional expression info.

llvm-svn: 63876

3 files changed, 19 insertions, 16 deletions

diff --git a/llvm/lib/Transforms/Scalar/CondPropagate.cpp b/llvm/lib/Transforms/Scalar/CondPropagate.cpp
index f68fb292e4a..1b755171c31 100644
--- a/llvm/lib/Transforms/Scalar/CondPropagate.cpp
+++ b/llvm/lib/Transforms/Scalar/CondPropagate.cpp
@@ -137,7 +137,7 @@ void CondProp::SimplifyPredecessors(BranchInst *BI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = BI->getParent();
-  if (&*BB->begin() != PN || &*next(BB->begin()) != BI)
+  if (!isTerminatorFirstRelevantInsn (BB, BI))
     return;
 
   // Ok, we have this really simple case, walk the PHI operands, looking for
@@ -171,7 +171,7 @@ void CondProp::SimplifyPredecessors(SwitchInst *SI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = SI->getParent();
-  if (&*BB->begin() != PN || &*next(BB->begin()) != SI)
+  if (!isTerminatorFirstRelevantInsn (BB, SI))
     return;
 
   bool RemovedPreds = false;
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index c22485342e0..aa6efe80b32 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -148,6 +148,23 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
   return false;
 }
 
+//===----------------------------------------------------------------------===//
+//  CFG Simplification
+//
+
+/// isTerminatorFirstRelevantInsn - Return true if Term is very first 
+/// instruction ignoring Phi nodes and dbg intrinsics.
+bool llvm::isTerminatorFirstRelevantInsn(BasicBlock *BB, Instruction *Term) {
+  BasicBlock::iterator BBI = Term;
+  while (BBI != BB->begin()) {
+    --BBI;
+    if (!isa<DbgInfoIntrinsic>(BBI))
+      break;
+  }
+  if (isa<PHINode>(BBI) || &*BBI == Term)
+    return true;
+  return false;
+}
 
 //===----------------------------------------------------------------------===//
 //  Local dead code elimination...
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index d9c4b69e6de..0248d3d0ca0 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1330,20 +1330,6 @@ static bool FoldTwoEntryPHINode(PHINode *PN) {
   return true;
 }
 
-/// isTerminatorFirstRelevantInsn - Return true if Term is very first 
-/// instruction ignoring Phi nodes and dbg intrinsics.
-static bool isTerminatorFirstRelevantInsn(BasicBlock *BB, Instruction *Term) {
-  BasicBlock::iterator BBI = Term;
-  while (BBI != BB->begin()) {
-    --BBI;
-    if (!isa<DbgInfoIntrinsic>(BBI))
-      break;
-  }
-  if (isa<PHINode>(BBI) || &*BBI == Term)
-    return true;
-  return false;
-}
-
 /// SimplifyCondBranchToTwoReturns - If we found a conditional branch that goes
 /// to two returning blocks, try to merge them together into one return,
 /// introducing a select if the return values disagree.