[llvm-branch-commits] [llvm] 1f6e155 - [LV] Weaken a unnecessarily strong assert [NFC]

[Philip Reames via llvm-branch-commits]

Author: Philip Reames
Date: 2020-12-15T19:07:53-08:00
New Revision: 1f6e15566f147f5814b0fe04df71a8d6acc4e689

URL: https://github.com/llvm/llvm-project/commit/1f6e15566f147f5814b0fe04df71a8d6acc4e689
DIFF: https://github.com/llvm/llvm-project/commit/1f6e15566f147f5814b0fe04df71a8d6acc4e689.diff

LOG: [LV] Weaken a unnecessarily strong assert [NFC]

Account for the fact that (in the future) the latch might be a switch not a branch.  The existing code is correct, minus the assert.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index cbeb6a32825f..37863b035067 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -3409,14 +3409,7 @@ BasicBlock *InnerLoopVectorizer::completeLoopSkeleton(Loop *L,
   Value *Count = getOrCreateTripCount(L);
   Value *VectorTripCount = getOrCreateVectorTripCount(L);
 
-  // We need the OrigLoop (scalar loop part) latch terminator to help
-  // produce correct debug info for the middle block BB instructions.
-  // The legality check stage guarantees that the loop will have a single
-  // latch.
-  assert(isa<BranchInst>(OrigLoop->getLoopLatch()->getTerminator()) &&
-         "Scalar loop latch terminator isn't a branch");
-  BranchInst *ScalarLatchBr =
-      cast<BranchInst>(OrigLoop->getLoopLatch()->getTerminator());
+  auto *ScalarLatchTerm = OrigLoop->getLoopLatch()->getTerminator();
 
   // Add a check in the middle block to see if we have completed
   // all of the iterations in the first vector loop.
@@ -3428,16 +3421,16 @@ BasicBlock *InnerLoopVectorizer::completeLoopSkeleton(Loop *L,
                            VectorTripCount, "cmp.n",
                            LoopMiddleBlock->getTerminator());
 
-    // Here we use the same DebugLoc as the scalar loop latch branch instead
+    // Here we use the same DebugLoc as the scalar loop latch terminator instead
     // of the corresponding compare because they may have ended up with
     // 
diff erent line numbers and we want to avoid awkward line stepping while
     // debugging. Eg. if the compare has got a line number inside the loop.
-    cast<Instruction>(CmpN)->setDebugLoc(ScalarLatchBr->getDebugLoc());
+    cast<Instruction>(CmpN)->setDebugLoc(ScalarLatchTerm->getDebugLoc());
   }
 
   BranchInst *BrInst =
       BranchInst::Create(LoopExitBlock, LoopScalarPreHeader, CmpN);
-  BrInst->setDebugLoc(ScalarLatchBr->getDebugLoc());
+  BrInst->setDebugLoc(ScalarLatchTerm->getDebugLoc());
   ReplaceInstWithInst(LoopMiddleBlock->getTerminator(), BrInst);
 
   // Get ready to start creating new instructions into the vectorized body.