From: Gil Rapaport <gil.rapaport@intel.com>
Date: Tue, 25 Apr 2017 05:57:22 +0000 (+0000)
Subject: [LV] Remove redundant basic block split
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e9d7fd8bfec89fdf1def4c3ad0a5b6341ba65cd7;p=llvm

[LV] Remove redundant basic block split

This patch is part of D28975's breakdown.

Genreating the control-flow to guard predicated instructions modified to
only use SplitBlockAndInsertIfThen() for producing the if-then construct.

Differential Revision: https://reviews.llvm.org/D32224


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301293 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp
index bc7c54dc4a3..30f739934bb 100644
--- a/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -4516,14 +4516,15 @@ void InnerLoopVectorizer::predicateInstructions() {
   for (auto KV : PredicatedInstructions) {
     BasicBlock::iterator I(KV.first);
     BasicBlock *Head = I->getParent();
-    auto *BB = SplitBlock(Head, &*std::next(I), DT, LI);
     auto *T = SplitBlockAndInsertIfThen(KV.second, &*I, /*Unreachable=*/false,
                                         /*BranchWeights=*/nullptr, DT, LI);
     I->moveBefore(T);
     sinkScalarOperands(&*I);
 
-    I->getParent()->setName(Twine("pred.") + I->getOpcodeName() + ".if");
-    BB->setName(Twine("pred.") + I->getOpcodeName() + ".continue");
+    BasicBlock *PredicatedBlock = I->getParent();
+    Twine BBNamePrefix = Twine("pred.") + I->getOpcodeName();
+    PredicatedBlock->setName(BBNamePrefix + ".if");
+    PredicatedBlock->getSingleSuccessor()->setName(BBNamePrefix + ".continue");
 
     // If the instruction is non-void create a Phi node at reconvergence point.
     if (!I->getType()->isVoidTy()) {