Index: clang/lib/CodeGen/CodeGenModule.cpp
===================================================================
--- clang/lib/CodeGen/CodeGenModule.cpp
+++ clang/lib/CodeGen/CodeGenModule.cpp
@@ -591,6 +591,24 @@
                               1);
   }
 
+  if (Context.getLangOpts().BranchTargetEnforcement) {
+    getModule().addModuleFlag(llvm::Module::Override,
+                              "branch-target-enforcement", 1);
+  }
+
+  if (Context.getLangOpts().hasSignReturnAddress()) {
+    getModule().addModuleFlag(
+        llvm::Module::Override, "sign-return-address",
+        Context.getLangOpts().isSignReturnAddressScopeAll()
+            ? llvm::MDString::get(VMContext, "all")
+            : llvm::MDString::get(VMContext, "non-leaf"));
+    getModule().addModuleFlag(
+        llvm::Module::Override, "sign-return-address-key",
+        Context.getLangOpts().isSignReturnAddressWithAKey()
+            ? llvm::MDString::get(VMContext, "a_key")
+            : llvm::MDString::get(VMContext, "b_key"));
+  }
+
   if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) {
     // Indicate whether __nvvm_reflect should be configured to flush denormal
     // floating point values to 0.  (This corresponds to its "__CUDA_FTZ"
Index: llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
===================================================================
--- llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
+++ llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp
@@ -189,33 +189,12 @@
     return;
 
   // Assemble feature flags that may require creation of a note section.
-  unsigned Flags = ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI |
-                   ELF::GNU_PROPERTY_AARCH64_FEATURE_1_PAC;
-
-  if (any_of(M, [](const Function &F) {
-        return !F.isDeclaration() &&
-               !F.hasFnAttribute("branch-target-enforcement");
-      })) {
-    Flags &= ~ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
-  }
-
-  if ((Flags & ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI) == 0 &&
-      any_of(M, [](const Function &F) {
-        return F.hasFnAttribute("branch-target-enforcement");
-      })) {
-    errs() << "warning: some functions compiled with BTI and some compiled "
-              "without BTI\n"
-           << "warning: not setting BTI in feature flags\n";
-  }
+  unsigned Flags = 0;
 
-  if (any_of(M, [](const Function &F) {
-        if (F.isDeclaration())
-          return false;
-        Attribute A = F.getFnAttribute("sign-return-address");
-        return !A.isStringAttribute() || A.getValueAsString() == "none";
-      })) {
-    Flags &= ~ELF::GNU_PROPERTY_AARCH64_FEATURE_1_PAC;
-  }
+  if (M.getModuleFlag("branch-target-enforcement"))
+    Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
+  if (M.getModuleFlag("sign-return-address"))
+    Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_PAC;
 
   if (Flags == 0)
     return;
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-0.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-0.ll
+++ llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-0.ll
@@ -4,7 +4,10 @@
 ; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
 @x = common dso_local global i32 0, align 4
 
-attributes #0 = { "branch-target-enforcement" }
+!llvm.module.flags = !{!0, !1}
+
+!0 = !{i32 4, !"branch-target-enforcement", i32 1}
+!1 = !{i32 4, !"sign-return-address", !"all"}
 
 ; Both attributes present in a file with no functions.
 ; ASM:	    .word	3221225472
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-1.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-1.ll
+++ llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-1.ll
@@ -3,12 +3,14 @@
 ; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - |  \
 ; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
 
-define dso_local i32 @f() #0 {
+define dso_local i32 @f() {
 entry:
   ret i32 0
 }
 
-attributes #0 = { "branch-target-enforcement" }
+!llvm.module.flags = !{!0}
+
+!0 = !{i32 4, !"branch-target-enforcement", i32 1}
 
 ; BTI attribute present
 ; ASM:	    .word	3221225472
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-2.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-2.ll
+++ llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-2.ll
@@ -3,12 +3,14 @@
 ; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - |  \
 ; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
 
-define dso_local i32 @f() #0 {
+define dso_local i32 @f() {
 entry:
   ret i32 0
 }
 
-attributes #0 = { "sign-return-address"="all" }
+!llvm.module.flags = !{!0}
+
+!0 = !{i32 4, !"sign-return-address", !"all"}
 
 ; PAC attribute present
 ; ASM:	    .word	3221225472
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-3.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-3.ll
+++ llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-3.ll
@@ -3,12 +3,15 @@
 ; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - |  \
 ; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
 
-define dso_local i32 @f() #0 {
+define dso_local i32 @f() {
 entry:
   ret i32 0
 }
 
-attributes #0 = { "branch-target-enforcement" "sign-return-address"="non-leaf" }
+!llvm.module.flags = !{!0, !1}
+
+!0 = !{i32 4, !"branch-target-enforcement", i32 1}
+!1 = !{i32 4, !"sign-return-address", !"non-leaf"}
 
 ; Both attribute present
 ; ASM:	    .word	3221225472
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-4.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-4.ll
+++ llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-4.ll
@@ -1,25 +1,12 @@
 ; RUN: llc -mtriple=aarch64-linux %s               -o - | \
 ; RUN:   FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - |  \
-; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
 
 define dso_local i32 @f() #0 {
 entry:
   ret i32 0
 }
 
-define dso_local i32 @g() #1 {
-entry:
-  ret i32 0
-}
-
 attributes #0 = { "branch-target-enforcement" "sign-return-address"="non-leaf" }
 
-attributes #1 = { "branch-target-enforcement" }
-
-; Only the common atttribute (BTI)
-; ASM:	    .word	3221225472
-; ASM-NEXT:	.word	4
-; ASM-NEXT:	.word	1
-
-; OBJ: Properties: aarch64 feature: BTI
+; Note is not emited if module has no properties
+; ASM-NOT: .note.gnu.property
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-5.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-5.ll
+++ /dev/null
@@ -1,26 +0,0 @@
-; RUN: llc -mtriple=aarch64-linux %s               -o - 2>&1 | \
-; RUN:   FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o -      |  \
-; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
-
-define dso_local i32 @f() #0 {
-entry:
-  ret i32 0
-}
-
-define dso_local i32 @g() #1 {
-entry:
-  ret i32 0
-}
-
-attributes #0 = { "branch-target-enforcement" "sign-return-address"="non-leaf" }
-
-attributes #1 = { "sign-return-address"="all" }
-
-; Only the common atttribute (PAC)
-; ASM: warning: not setting BTI in feature flags
-; ASM:	    .word	3221225472
-; ASM-NEXT:	.word	4
-; ASM-NEXT:	.word	2
-
-; OBJ: Properties: aarch64 feature: PAC
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-6.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-6.ll
+++ /dev/null
@@ -1,22 +0,0 @@
-; RUN: llc -mtriple=aarch64-linux %s               -o - | \
-; RUN:   FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - |  \
-; RUN:   llvm-readelf -S | FileCheck %s --check-prefix=OBJ
-
-define dso_local i32 @f() #0 {
-entry:
-  ret i32 0
-}
-
-define dso_local i32 @g() #1 {
-entry:
-  ret i32 0
-}
-
-attributes #0 = { "sign-return-address"="non-leaf" }
-
-attributes #1 = { "sign-return-address"="none" }
-
-; No common attribute, no note section
-; ASM-NOT: .note.gnu.property
-; OBJ-NOT: .note.gnu.property
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-7.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-7.ll
+++ /dev/null
@@ -1,23 +0,0 @@
-; RUN: llc -mtriple=aarch64-linux %s               -o - 2>&1 | \
-; RUN:   FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o -      |  \
-; RUN:   llvm-readelf -S | FileCheck %s --check-prefix=OBJ
-
-define dso_local i32 @f() #0 {
-entry:
-  ret i32 0
-}
-
-define dso_local i32 @g() #1 {
-entry:
-  ret i32 0
-}
-
-attributes #0 = { "sign-return-address"="non-leaf" }
-
-attributes #1 = { "branch-target-enforcement" }
-
-; No common attribute, no note section
-; ASM: warning: not setting BTI in feature flags
-; ASM-NOT: .note.gnu.property
-; OBJ-NOT: .note.gnu.property
Index: llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-8.ll
===================================================================
--- llvm/test/CodeGen/AArch64/note-gnu-property-pac-bti-8.ll
+++ /dev/null
@@ -1,21 +0,0 @@
-; RUN: llc -mtriple=aarch64-linux %s               -o - | \
-; RUN:   FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=aarch64-linux %s -filetype=obj -o - | \
-; RUN:   llvm-readelf --notes | FileCheck %s --check-prefix=OBJ
-
-define dso_local i32 @f() #0 {
-entry:
-  %r = tail call i32 @g()
-  ret i32 %r
-}
-
-declare dso_local i32 @g()
-
-attributes #0 = { "branch-target-enforcement" }
-
-; Declarations don't prevent setting BTI
-; ASM:	    .word	3221225472
-; ASM-NEXT:	.word	4
-; ASM-NEXT:	.word	1
-
-; OBJ: Properties: aarch64 feature: BTI