[llvm] r307276 - [SimplifyCFG] Move a portion of an if statement that should already be implied to an assert

[Craig Topper via llvm-commits]

Author: ctopper
Date: Thu Jul  6 09:29:43 2017
New Revision: 307276

URL: http://llvm.org/viewvc/llvm-project?rev=307276&view=rev
Log:
[SimplifyCFG]  Move a portion of an if statement that should already be implied to an assert

Summary: In this code we got to Dom by following the predecessor link of BB. So it stands to reason that BB should also show up as a successor of Dom's terminator right? There isn't a way to have the CFG connect in only one direction is there?

Reviewers: jmolloy, davide, mcrosier

Reviewed By: mcrosier

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D35025

Modified:
    llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp

Modified: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp?rev=307276&r1=307275&r2=307276&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp Thu Jul  6 09:29:43 2017
@@ -5754,8 +5754,8 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
   if (BasicBlock *Dom = BB->getSinglePredecessor()) {
     auto *PBI = dyn_cast_or_null<BranchInst>(Dom->getTerminator());
     if (PBI && PBI->isConditional() &&
-        PBI->getSuccessor(0) != PBI->getSuccessor(1) &&
-        (PBI->getSuccessor(0) == BB || PBI->getSuccessor(1) == BB)) {
+        PBI->getSuccessor(0) != PBI->getSuccessor(1)) {
+      assert(PBI->getSuccessor(0) == BB || PBI->getSuccessor(1) == BB);
       bool CondIsFalse = PBI->getSuccessor(1) == BB;
       Optional<bool> Implication = isImpliedCondition(
           PBI->getCondition(), BI->getCondition(), DL, CondIsFalse);