Index: lib/Transforms/Utils/SplitModule.cpp
===================================================================
--- lib/Transforms/Utils/SplitModule.cpp
+++ lib/Transforms/Utils/SplitModule.cpp
@@ -88,6 +88,13 @@
         Member = &GV;
     }
 
+    // For aliases we should not separate them from their aliasees regardless
+    // of linkage.
+    if (GlobalAlias *GA = dyn_cast<GlobalAlias>(&GV)) {
+      if (const GlobalObject *Base = GA->getBaseObject())
+        GVtoClusterMap.unionSets(&GV, Base);
+    }
+
     // Further only iterate over local GVs.
     if (!GV.hasLocalLinkage())
       return;
Index: test/tools/llvm-split/scc-const-alias.ll
===================================================================
--- /dev/null
+++ test/tools/llvm-split/scc-const-alias.ll
@@ -0,0 +1,38 @@
+; We should never separate alias from aliasee.
+; RUN: llvm-split -j=3 -preserve-locals -o %t %s
+; RUN: llvm-dis -o - %t0 | FileCheck --check-prefix=CHECK0 %s
+; RUN: llvm-dis -o - %t1 | FileCheck --check-prefix=CHECK1 %s
+; RUN: llvm-dis -o - %t2 | FileCheck --check-prefix=CHECK2 %s
+
+; Checks are not critical here - verifier will assert if we fail.
+; CHECK0: @g1 = global i32 99
+; CHECK0: @c1Alias = external global i8
+; CHECK0: @g1Alias = internal alias i8, bitcast (i32* @g1 to i8*)
+
+; CHECK1: @g1 = external global i32
+; CHECK1: @c1Alias = internal alias i8, inttoptr (i64 42 to i8*)
+
+; Third file is actually empty.
+; CHECK2: @g1 = external global i32
+; CHECK2: @g1Alias = external global i8
+; CHECK2: @c1Alias = external global i8
+
+@g1 = global i32 99
+
+@g1Alias = internal alias i8, bitcast (i32* @g1 to i8*)
+@c1Alias = internal alias i8, inttoptr (i64 42 to i8*)
+@funExternalAlias = alias i8 (), i8 ()* @funExternal
+
+define i8 @funExternal() {
+entry:
+  %x = load i8, i8* @g1Alias
+  ret i8 %x
+}
+
+define i8 @funExternal2() {
+entry:
+  %x = load i8, i8* @c1Alias
+  %y = call i8 @funExternalAlias()
+  %z = add i8 %x, %y
+  ret i8 %z
+}
Index: test/tools/llvm-split/scc-global-alias.ll
===================================================================
--- /dev/null
+++ test/tools/llvm-split/scc-global-alias.ll
@@ -0,0 +1,47 @@
+; We should never separate alias from aliasee.
+; RUN: llvm-split -j=3 -preserve-locals -o %t %s
+; RUN: llvm-dis -o - %t0 | FileCheck --check-prefix=CHECK0 %s
+; RUN: llvm-dis -o - %t1 | FileCheck --check-prefix=CHECK1 %s
+; RUN: llvm-dis -o - %t2 | FileCheck --check-prefix=CHECK2 %s
+
+; Checks are not critical here - verifier will assert if we fail.
+; CHECK0: @funInternal2Alias = alias
+; CHECK0: @funExternal2Alias = alias
+; CHECK0: define internal i32 @funInternal2
+; CHECK0: define i32 @funExternal2
+
+; CHECK1: @funInternalAlias = alias
+; CHECK1: define internal i32 @funInternal
+
+; CHECK2: @funExternalAlias = alias
+; CHECK2: define i32 @funExternal
+
+@funInternalAlias = alias i32 (), i32 ()* @funInternal
+@funExternalAlias = alias i32 (), i32 ()* @funExternal
+@funInternal2Alias = alias i32 (), i32 ()* @funInternal2
+@funExternal2Alias = alias i32 (), i32 ()* @funExternal2
+
+define internal i32 @funInternal() {
+entry:
+  ret i32 0
+}
+
+define i32 @funExternal() {
+entry:
+  %x = call i32 @funInternalAlias()
+  ret i32 %x
+}
+
+define internal i32 @funInternal2() {
+entry:
+  %x = call i32 @funInternalAlias()
+  ret i32 %x
+}
+
+define i32 @funExternal2() {
+entry:
+  %x = call i32 @funInternal2()
+  %y = call i32 @funExternalAlias()
+  %z = add nsw i32 %x, %y
+  ret i32 %z
+}