diff --git a/compiler-rt/lib/msan/msan.cpp b/compiler-rt/lib/msan/msan.cpp
--- a/compiler-rt/lib/msan/msan.cpp
+++ b/compiler-rt/lib/msan/msan.cpp
@@ -380,6 +380,28 @@
   Die();
 }
 
+void __msan_warning_with_origin(u32 origin) {
+  GET_CALLER_PC_BP_SP;
+  (void)sp;
+  PrintWarningWithOrigin(pc, bp, origin);
+  if (__msan::flags()->halt_on_error) {
+    if (__msan::flags()->print_stats)
+      ReportStats();
+    Printf("Exiting\n");
+    Die();
+  }
+}
+
+void __msan_warning_with_origin_noreturn(u32 origin) {
+  GET_CALLER_PC_BP_SP;
+  (void)sp;
+  PrintWarningWithOrigin(pc, bp, origin);
+  if (__msan::flags()->print_stats)
+    ReportStats();
+  Printf("Exiting\n");
+  Die();
+}
+
 static void OnStackUnwind(const SignalContext &sig, const void *,
                           BufferedStackTrace *stack) {
   stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
diff --git a/compiler-rt/lib/msan/msan_interface_internal.h b/compiler-rt/lib/msan/msan_interface_internal.h
--- a/compiler-rt/lib/msan/msan_interface_internal.h
+++ b/compiler-rt/lib/msan/msan_interface_internal.h
@@ -46,6 +46,12 @@
 using __sanitizer::u16;
 using __sanitizer::u8;
 
+// Versions of the above which take Origin as a parameter
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_warning_with_origin(u32 origin);
+SANITIZER_INTERFACE_ATTRIBUTE __attribute__((noreturn))
+void __msan_warning_with_origin_noreturn(u32 origin);
+
 SANITIZER_INTERFACE_ATTRIBUTE
 void __msan_maybe_warning_1(u8 s, u32 o);
 SANITIZER_INTERFACE_ATTRIBUTE
diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -557,6 +557,9 @@
   /// The run-time callback to print a warning.
   FunctionCallee WarningFn;
 
+  /// True if Origin is passed as a parameter, false if over TLS.
+  bool WarningFnTakesOrigin;
+
   // These arrays are indexed by log2(AccessSize).
   FunctionCallee MaybeWarningFn[kNumberOfAccessSizes];
   FunctionCallee MaybeStoreOriginFn[kNumberOfAccessSizes];
@@ -723,6 +726,7 @@
   OriginTLS = nullptr;
 
   // __msan_warning() in the kernel takes an origin.
+  WarningFnTakesOrigin = true;
   WarningFn = M.getOrInsertFunction("__msan_warning", IRB.getVoidTy(),
                                     IRB.getInt32Ty());
   // Requests the per-task context state (kmsan_context_state*) from the
@@ -777,12 +781,22 @@
 /// Insert declarations for userspace-specific functions and globals.
 void MemorySanitizer::createUserspaceApi(Module &M) {
   IRBuilder<> IRB(*C);
+
+  // Enable origin as param with eager checks, as a space saving measure.
+  WarningFnTakesOrigin = ClEagerChecks;
+
   // Create the callback.
   // FIXME: this function should have "Cold" calling conv,
   // which is not yet implemented.
-  StringRef WarningFnName = Recover ? "__msan_warning"
-                                    : "__msan_warning_noreturn";
-  WarningFn = M.getOrInsertFunction(WarningFnName, IRB.getVoidTy());
+  std::string WarningFnName = "__msan_warning";
+  if (WarningFnTakesOrigin)
+    WarningFnName += "_with_origin";
+  if (!Recover)
+    WarningFnName += "_noreturn";
+  if (WarningFnTakesOrigin)
+    WarningFn = M.getOrInsertFunction(WarningFnName, IRB.getVoidTy(), IRB.getInt32Ty());
+  else
+    WarningFn = M.getOrInsertFunction(WarningFnName, IRB.getVoidTy());
 
   // Create the global TLS variables.
   RetvalTLS =
@@ -1248,7 +1262,8 @@
   void insertWarningFn(IRBuilder<> &IRB, Value *Origin) {
     if (!Origin)
       Origin = (Value *)IRB.getInt32(0);
-    if (MS.CompileKernel) {
+    if (MS.WarningFnTakesOrigin) {
+      assert(Origin->getType()->isIntegerTy());
       IRB.CreateCall(MS.WarningFn, Origin);
     } else {
       if (MS.TrackOrigins) {