vendor/llvm/llvm-trunk-r366426

1 files changed, 17 insertions, 5 deletions

diff --git a/lib/Transforms/Scalar/LoopDistribute.cpp b/lib/Transforms/Scalar/LoopDistribute.cpp
index d797c9dc9e72..f45e5fd0f50b 100644
--- a/lib/Transforms/Scalar/LoopDistribute.cpp
+++ b/lib/Transforms/Scalar/LoopDistribute.cpp
@@ -1,9 +1,8 @@
 //===- LoopDistribute.cpp - Loop Distribution Pass ------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
@@ -767,8 +766,14 @@ public:
                     "cannot isolate unsafe dependencies");
     }
 
-    // Don't distribute the loop if we need too many SCEV run-time checks.
+    // Don't distribute the loop if we need too many SCEV run-time checks, or
+    // any if it's illegal.
     const SCEVUnionPredicate &Pred = LAI->getPSE().getUnionPredicate();
+    if (LAI->hasConvergentOp() && !Pred.isAlwaysTrue()) {
+      return fail("RuntimeCheckWithConvergent",
+                  "may not insert runtime check with convergent operation");
+    }
+
     if (Pred.getComplexity() > (IsForced.getValueOr(false)
                                     ? PragmaDistributeSCEVCheckThreshold
                                     : DistributeSCEVCheckThreshold))
@@ -796,7 +801,14 @@ public:
     auto Checks = includeOnlyCrossPartitionChecks(AllChecks, PtrToPartition,
                                                   RtPtrChecking);
 
+    if (LAI->hasConvergentOp() && !Checks.empty()) {
+      return fail("RuntimeCheckWithConvergent",
+                  "may not insert runtime check with convergent operation");
+    }
+
     if (!Pred.isAlwaysTrue() || !Checks.empty()) {
+      assert(!LAI->hasConvergentOp() && "inserting illegal loop versioning");
+
       MDNode *OrigLoopID = L->getLoopID();
 
       LLVM_DEBUG(dbgs() << "\nPointers:\n");