diff --git a/llvm/lib/Transforms/Scalar/GVNHoist.cpp b/llvm/lib/Transforms/Scalar/GVNHoist.cpp
index e7179a342c22..0b5e94f8fb90 100644
--- a/llvm/lib/Transforms/Scalar/GVNHoist.cpp
+++ b/llvm/lib/Transforms/Scalar/GVNHoist.cpp
@@ -628,7 +628,6 @@ public:
             cast<Instruction>(cast<StoreInst>(OtherInst)->getValueOperand());
         ClonedVal->intersectOptionalDataWith(OtherVal);
       }
-      ClonedVal->clearSubclassOptionalData();
       Repl->replaceUsesOfWith(Val, ClonedVal);
     }
 
@@ -685,12 +684,23 @@ public:
       for (Instruction *I : InstructionsToHoist)
         if (I != Repl) {
           ++NR;
-          if (isa<LoadInst>(Repl))
+          if (auto *ReplacementLoad = dyn_cast<LoadInst>(Repl)) {
+            ReplacementLoad->setAlignment(
+                std::min(ReplacementLoad->getAlignment(),
+                         cast<LoadInst>(I)->getAlignment()));
             ++NumLoadsRemoved;
-          else if (isa<StoreInst>(Repl))
+          } else if (auto *ReplacementStore = dyn_cast<StoreInst>(Repl)) {
+            ReplacementStore->setAlignment(
+                std::min(ReplacementStore->getAlignment(),
+                         cast<StoreInst>(I)->getAlignment()));
             ++NumStoresRemoved;
-          else if (isa<CallInst>(Repl))
+          } else if (auto *ReplacementAlloca = dyn_cast<AllocaInst>(Repl)) {
+            ReplacementAlloca->setAlignment(
+                std::max(ReplacementAlloca->getAlignment(),
+                         cast<AllocaInst>(I)->getAlignment()));
+          } else if (isa<CallInst>(Repl)) {
             ++NumCallsRemoved;
+          }
           Repl->intersectOptionalDataWith(I);
           I->replaceAllUsesWith(Repl);
           I->eraseFromParent();
diff --git a/llvm/test/Transforms/GVN/hoist.ll b/llvm/test/Transforms/GVN/hoist.ll
index 9c2c425a1a72..01fedff306b6 100644
--- a/llvm/test/Transforms/GVN/hoist.ll
+++ b/llvm/test/Transforms/GVN/hoist.ll
@@ -689,3 +689,24 @@ if.else:                                          ; preds = %entry
 if.end:                                           ; preds = %if.else, %if.then
   ret void
 }
+
+define i32 @mergeAlignments(i1 %b, i32* %y) {
+entry:
+  br i1 %b, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %l1 = load i32, i32* %y, align 4
+  br label %return
+
+if.end:                                           ; preds = %entry
+  %l2 = load i32, i32* %y, align 1
+  br label %return
+
+return:                                           ; preds = %if.end, %if.then
+  %retval.0 = phi i32 [ %l1, %if.then ], [ %l2, %if.end ]
+  ret i32 %retval.0
+}
+; CHECK-LABEL: define i32 @mergeAlignments(
+; CHECK: %[[load:.*]] = load i32, i32* %y, align 1
+; CHECK: %[[phi:.*]] = phi i32 [ %[[load]], %{{.*}} ], [ %[[load]], %{{.*}} ]
+; CHECK: i32 %[[phi]]