Add an explicit insert point argument to SplitBlockAndInsertIfThen.

Currently SplitBlockAndInsertIfThen requires that branch condition is an
Instruction itself, which is very inconvenient, because it is sometimes an
Operator, or even a Constant.

llvm-svn: 197677
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 12de9ee..17bd115 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -630,28 +630,29 @@
 }
 
 /// SplitBlockAndInsertIfThen - Split the containing block at the
-/// specified instruction - everything before and including Cmp stays
-/// in the old basic block, and everything after Cmp is moved to a
+/// specified instruction - everything before and including SplitBefore stays
+/// in the old basic block, and everything after SplitBefore is moved to a
 /// new block. The two blocks are connected by a conditional branch
 /// (with value of Cmp being the condition).
 /// Before:
 ///   Head
-///   Cmp
+///   SplitBefore
 ///   Tail
 /// After:
 ///   Head
-///   Cmp
-///   if (Cmp)
+///   if (Cond)
 ///     ThenBlock
+///   SplitBefore
 ///   Tail
 ///
 /// If Unreachable is true, then ThenBlock ends with
 /// UnreachableInst, otherwise it branches to Tail.
 /// Returns the NewBasicBlock's terminator.
 
-TerminatorInst *llvm::SplitBlockAndInsertIfThen(Instruction *Cmp,
-    bool Unreachable, MDNode *BranchWeights) {
-  Instruction *SplitBefore = Cmp->getNextNode();
+TerminatorInst *llvm::SplitBlockAndInsertIfThen(Value *Cond,
+                                                Instruction *SplitBefore,
+                                                bool Unreachable,
+                                                MDNode *BranchWeights) {
   BasicBlock *Head = SplitBefore->getParent();
   BasicBlock *Tail = Head->splitBasicBlock(SplitBefore);
   TerminatorInst *HeadOldTerm = Head->getTerminator();
@@ -663,7 +664,7 @@
   else
     CheckTerm = BranchInst::Create(Tail, ThenBlock);
   BranchInst *HeadNewTerm =
-    BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/Tail, Cmp);
+    BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/Tail, Cond);
   HeadNewTerm->setMetadata(LLVMContext::MD_prof, BranchWeights);
   ReplaceInstWithInst(HeadOldTerm, HeadNewTerm);
   return CheckTerm;