2 files changed, 41 insertions, 4 deletions
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index dae4af8bb24..66446626c2e 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -3115,10 +3115,17 @@ FunctionDecl *FunctionDecl::getCanonicalDecl() { return getFirstDecl(); }
 /// functions as their wrapped builtins. This shouldn't be done in general, but
 /// it's useful in Sema to diagnose calls to wrappers based on their semantics.
 unsigned FunctionDecl::getBuiltinID(bool ConsiderWrapperFunctions) const {
-  if (!getIdentifier())
-    return 0;
+  unsigned BuiltinID;
+
+  if (const auto *AMAA = getAttr<ArmMveAliasAttr>()) {
+    BuiltinID = AMAA->getBuiltinName()->getBuiltinID();
+  } else {
+    if (!getIdentifier())
+      return 0;
+
+    BuiltinID = getIdentifier()->getBuiltinID();
+  }
 
-  unsigned BuiltinID = getIdentifier()->getBuiltinID();
   if (!BuiltinID)
     return 0;
 
@@ -3142,7 +3149,8 @@ unsigned FunctionDecl::getBuiltinID(bool ConsiderWrapperFunctions) const {
 
   // If the function is marked "overloadable", it has a different mangled name
   // and is not the C library function.
-  if (!ConsiderWrapperFunctions && hasAttr<OverloadableAttr>())
+  if (!ConsiderWrapperFunctions && hasAttr<OverloadableAttr>() &&
+      !hasAttr<ArmMveAliasAttr>())
     return 0;
 
   if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index b2be6245a81..cebb1c642b9 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -23,6 +23,7 @@
 #include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/Basic/CharInfo.h"
 #include "clang/Basic/SourceManager.h"
+#include "clang/Basic/TargetBuiltins.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Sema/DeclSpec.h"
@@ -4830,6 +4831,30 @@ static void handleXRayLogArgsAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
                  XRayLogArgsAttr(S.Context, AL, ArgCount.getSourceIndex()));
 }
 
+static bool ArmMveAliasValid(unsigned BuiltinID, StringRef AliasName) {
+  // FIXME: this will be filled in by Tablegen which isn't written yet
+  return false;
+}
+
+static void handleArmMveAliasAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
+  if (!AL.isArgIdent(0)) {
+    S.Diag(AL.getLoc(), diag::err_attribute_argument_n_type)
+        << AL << 1 << AANT_ArgumentIdentifier;
+    return;
+  }
+
+  IdentifierInfo *Ident = AL.getArgAsIdent(0)->Ident;
+  unsigned BuiltinID = Ident->getBuiltinID();
+
+  if (!ArmMveAliasValid(BuiltinID,
+                        cast<FunctionDecl>(D)->getIdentifier()->getName())) {
+    S.Diag(AL.getLoc(), diag::err_attribute_arm_mve_alias);
+    return;
+  }
+
+  D->addAttr(::new (S.Context) ArmMveAliasAttr(S.Context, AL, Ident));
+}
+
 //===----------------------------------------------------------------------===//
 // Checker-specific attribute handlers.
 //===----------------------------------------------------------------------===//
@@ -7160,6 +7185,10 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case ParsedAttr::AT_MSAllocator:
     handleMSAllocatorAttr(S, D, AL);
     break;
+
+  case ParsedAttr::AT_ArmMveAlias:
+    handleArmMveAliasAttr(S, D, AL);
+    break;
   }
 }