Revert "[llvm][AArch64] Autoupgrade function attributes from Module attributes."

llvm/include/llvm/IR/AutoUpgrade.h

@@ -88,9 +88,6 @@ namespace llvm {
   /// info. Return true if module is modified.
   bool UpgradeDebugInfo(Module &M);
 
-  /// Copies module attributes to the functions in the module.
-  void CopyModuleAttrToFunctions(Module &M);
-
   /// Check whether a string looks like an old loop attachment tag.
   inline bool mayBeOldLoopAttachmentTag(StringRef Name) {
     return Name.starts_with("llvm.vectorizer.");

llvm/lib/IR/AutoUpgrade.cpp

@@ -5178,72 +5178,6 @@ void llvm::UpgradeFunctionAttributes(Function &F) {
     Arg.removeAttrs(AttributeFuncs::typeIncompatible(Arg.getType()));
 }
 
-// Check if the module attribute is present and not zero.
-static bool isModuleAttributeSet(Module &M, const StringRef &ModAttr) {
-  const auto *Attr =
-      mdconst::extract_or_null<ConstantInt>(M.getModuleFlag(ModAttr));
-  return Attr && Attr->getZExtValue();
-}
-
-// Copy an attribute from module to the function if exists.
-// First value of the pair is used when the module attribute is not zero
-// the second otherwise.
-static void
-CopyModuleAttributeToFunction(Function &F, StringRef FnAttrName,
-                              StringRef ModAttrName,
-                              std::pair<StringRef, StringRef> Values) {
-  if (F.hasFnAttribute(FnAttrName))
-    return;
-  F.addFnAttr(FnAttrName, isModuleAttributeSet(*F.getParent(), ModAttrName)
-                              ? Values.first
-                              : Values.second);
-}
-
-// Copy a boolean attribute from module to the function if exists.
-// Module attribute treated false if zero otherwise true.
-static void CopyModuleAttributeToFunction(Function &F, StringRef AttrName) {
-  CopyModuleAttributeToFunction(
-      F, AttrName, AttrName,
-      std::make_pair<StringRef, StringRef>("true", "false"));
-}
-
-// Copy an attribute from module to the function if exists.
-// First value of the pair is used when the module attribute is not zero
-// the second otherwise.
-static void
-CopyModuleAttributeToFunction(Function &F, StringRef AttrName,
-                              std::pair<StringRef, StringRef> Values) {
-  CopyModuleAttributeToFunction(F, AttrName, AttrName, Values);
-}
-
-void llvm::CopyModuleAttrToFunctions(Module &M) {
-  Triple T(M.getTargetTriple());
-  if (!T.isThumb() && !T.isARM() && !T.isAArch64())
-    return;
-
-  for (Function &F : M.getFunctionList()) {
-    if (F.isDeclaration())
-      continue;
-
-    if (!F.hasFnAttribute("sign-return-address")) {
-      StringRef SignType = "none";
-      if (isModuleAttributeSet(M, "sign-return-address"))
-        SignType = "non-leaf";
-
-      if (isModuleAttributeSet(M, "sign-return-address-all"))
-        SignType = "all";
-
-      F.addFnAttr("sign-return-address", SignType);
-    }
-    CopyModuleAttributeToFunction(F, "branch-target-enforcement");
-    CopyModuleAttributeToFunction(F, "branch-protection-pauth-lr");
-    CopyModuleAttributeToFunction(F, "guarded-control-stack");
-    CopyModuleAttributeToFunction(
-        F, "sign-return-address-key",
-        std::make_pair<StringRef, StringRef>("b_key", "a_key"));
-  }
-}
-
 static bool isOldLoopArgument(Metadata *MD) {
   auto *T = dyn_cast_or_null<MDTuple>(MD);
   if (!T)

llvm/lib/Linker/IRMover.cpp

@@ -1606,11 +1606,6 @@ Error IRLinker::run() {
   // Loop over all of the linked values to compute type mappings.
   computeTypeMapping();
 
-  // Convert module level attributes to function level attributes because
-  // after merging modules the attributes might change and would have different
-  // effect on the functions as the original module would have.
-  CopyModuleAttrToFunctions(*SrcM);
-
   std::reverse(Worklist.begin(), Worklist.end());
   while (!Worklist.empty()) {
     GlobalValue *GV = Worklist.back();

llvm/test/LTO/AArch64/link-branch-target-enforcement.ll

@@ -32,7 +32,6 @@ entry:
 ; CHECK-DUMP: <main>:
 ; CHECK-DUMP:      bl      0x8 <main+0x8>
 ; CHECK-DUMP: <foo>:
-; CHECK-DUMP:     paciasp
 
 ; `main` doesn't support BTI while `foo` does, so in the binary
 ; we should see only PAC which is supported by both.

llvm/test/Linker/link-arm-and-thumb.ll

@@ -13,12 +13,11 @@ entry:
   ret i32 %add
 }
 
-; CHECK: define i32 @main() [[MAIN_ATTRS:#[0-9]+]]
+; CHECK: define i32 @main() {
 ; CHECK: define i32 @foo(i32 %a, i32 %b) [[ARM_ATTRS:#[0-9]+]]
 ; CHECK: define i32 @bar(i32 %a, i32 %b) [[THUMB_ATTRS:#[0-9]+]]
 
-; CHECK: attributes [[MAIN_ATTRS]] = { {{.*}} }
-; CHECK: attributes [[ARM_ATTRS]] = { {{.*}} "target-features"="-thumb-mode" }
-; CHECK: attributes [[THUMB_ATTRS]] = { {{.*}} "target-features"="+thumb-mode" }
+; CHECK: attributes [[ARM_ATTRS]] = { "target-features"="-thumb-mode" }
+; CHECK: attributes [[THUMB_ATTRS]] = { "target-features"="+thumb-mode" }
 
 ; STDERR-NOT: warning: Linking two modules of different target triples: