diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1512,6 +1512,12 @@
 
   // Now if needed, run the legacy PM for codegen.
   if (NeedCodeGen) {
+    // Save some memory by clearing analyses used in the optimization pipeline.
+    LAM.clear();
+    FAM.clear();
+    CGAM.clear();
+    MAM.clear();
+
     PrettyStackTraceString CrashInfo("Code generation");
     CodeGenPasses.run(*TheModule);
   }