InstCombine: fix sinking of convergent calls

llvm-svn: 251991
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index b51ec29..ac535f9 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -2694,6 +2694,12 @@
         &DestBlock->getParent()->getEntryBlock())
     return false;
 
+  // Do not sink convergent call instructions.
+  if (auto *CI = dyn_cast<CallInst>(I)) {
+    if (CI->isConvergent())
+      return false;
+  }
+
   // We can only sink load instructions if there is nothing between the load and
   // the end of block that could change the value.
   if (I->mayReadFromMemory()) {