Index: clang/test/Misc/target-invalid-cpu-note.c
===================================================================
--- clang/test/Misc/target-invalid-cpu-note.c
+++ clang/test/Misc/target-invalid-cpu-note.c
@@ -5,11 +5,11 @@
 
 // RUN: not %clang_cc1 -triple arm64--- -target-cpu not-a-cpu -fsyntax-only %s 2>&1 | FileCheck %s --check-prefix AARCH64
 // AARCH64: error: unknown target CPU 'not-a-cpu'
-// AARCH64-NEXT: note: valid target CPU values are: cortex-a34, cortex-a35, cortex-a53, cortex-a55, cortex-a510, cortex-a57, cortex-a65, cortex-a65ae, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a78, cortex-a78c, cortex-a710, cortex-r82, cortex-x1, cortex-x1c, cortex-x2, neoverse-e1, neoverse-n1, neoverse-n2, neoverse-512tvb, neoverse-v1, neoverse-v2, cyclone, apple-a7, apple-a8, apple-a9, apple-a10, apple-a11, apple-a12, apple-a13, apple-a14, apple-a15, apple-a16, apple-m1, apple-m2, apple-s4, apple-s5, exynos-m3, exynos-m4, exynos-m5, falkor, saphira, kryo, thunderx2t99, thunderx3t110, thunderx, thunderxt88, thunderxt81, thunderxt83, tsv110, a64fx, carmel, ampere1{{$}}
+// AARCH64-NEXT: note: valid target CPU values are: cortex-a34, cortex-a35, cortex-a53, cortex-a55, cortex-a510, cortex-a57, cortex-a65, cortex-a65ae, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a78, cortex-a78c, cortex-a710, cortex-r82, cortex-x1, cortex-x1c, cortex-x2, neoverse-e1, neoverse-n1, neoverse-n2, neoverse-512tvb, neoverse-v1, neoverse-v2, cyclone, apple-a7, apple-a8, apple-a9, apple-a10, apple-a11, apple-a12, apple-a13, apple-a14, apple-a15, apple-a16, apple-m1, apple-m2, apple-s4, apple-s5, exynos-m3, exynos-m4, exynos-m5, falkor, saphira, kryo, thunderx2t99, thunderx3t110, thunderx, thunderxt88, thunderxt81, thunderxt83, tsv110, a64fx, carmel, ampere1, grace{{$}}
 
 // RUN: not %clang_cc1 -triple arm64--- -tune-cpu not-a-cpu -fsyntax-only %s 2>&1 | FileCheck %s --check-prefix TUNE_AARCH64
 // TUNE_AARCH64: error: unknown target CPU 'not-a-cpu'
-// TUNE_AARCH64-NEXT: note: valid target CPU values are: cortex-a34, cortex-a35, cortex-a53, cortex-a55, cortex-a510, cortex-a57, cortex-a65, cortex-a65ae, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a78, cortex-a78c, cortex-a710, cortex-r82, cortex-x1, cortex-x1c, cortex-x2, neoverse-e1, neoverse-n1, neoverse-n2, neoverse-512tvb, neoverse-v1, neoverse-v2, cyclone, apple-a7, apple-a8, apple-a9, apple-a10, apple-a11, apple-a12, apple-a13, apple-a14, apple-a15, apple-a16,  apple-m1, apple-m2, apple-s4, apple-s5, exynos-m3, exynos-m4, exynos-m5, falkor, saphira, kryo, thunderx2t99, thunderx3t110, thunderx, thunderxt88, thunderxt81, thunderxt83, tsv110, a64fx, carmel, ampere1{{$}}
+// TUNE_AARCH64-NEXT: note: valid target CPU values are: cortex-a34, cortex-a35, cortex-a53, cortex-a55, cortex-a510, cortex-a57, cortex-a65, cortex-a65ae, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a78, cortex-a78c, cortex-a710, cortex-r82, cortex-x1, cortex-x1c, cortex-x2, neoverse-e1, neoverse-n1, neoverse-n2, neoverse-512tvb, neoverse-v1, neoverse-v2, cyclone, apple-a7, apple-a8, apple-a9, apple-a10, apple-a11, apple-a12, apple-a13, apple-a14, apple-a15, apple-a16,  apple-m1, apple-m2, apple-s4, apple-s5, exynos-m3, exynos-m4, exynos-m5, falkor, saphira, kryo, thunderx2t99, thunderx3t110, thunderx, thunderxt88, thunderxt81, thunderxt83, tsv110, a64fx, carmel, ampere1, grace{{$}}
 
 // RUN: not %clang_cc1 -triple i386--- -target-cpu not-a-cpu -fsyntax-only %s 2>&1 | FileCheck %s --check-prefix X86
 // X86: error: unknown target CPU 'not-a-cpu'
Index: llvm/include/llvm/Support/AArch64TargetParser.h
===================================================================
--- llvm/include/llvm/Support/AArch64TargetParser.h
+++ llvm/include/llvm/Support/AArch64TargetParser.h
@@ -109,6 +109,20 @@
 #include "AArch64TargetParser.def"
 };
 
+const struct {
+  const char *Alias;
+  size_t AliasLength;
+  const char *Name;
+  size_t NameLength;
+
+  StringRef getAlias() const { return StringRef(Alias, AliasLength); }
+  StringRef getName() const { return StringRef(Name, NameLength); }
+} AArch64CPUAliases[] = {
+#define AARCH64_CPU_ALIAS(ALIAS,NAME)                                          \
+  {ALIAS, sizeof(ALIAS) - 1, NAME, sizeof(NAME) - 1},
+#include "AArch64TargetParser.def"
+};
+
 const ArchKind ArchKinds[] = {
 #define AARCH64_ARCH(NAME, ID, CPU_ATTR, SUB_ARCH, ARCH_ATTR, ARCH_FPU, ARCH_BASE_EXT) \
     ArchKind::ID,
@@ -138,13 +152,7 @@
 StringRef getArchExtName(unsigned ArchExtKind);
 StringRef getArchExtFeature(StringRef ArchExt);
 ArchKind convertV9toV8(ArchKind AK);
-
-// FIXME: We should be able to define CPU aliases in TargetParser.
-inline StringRef resolveCPUAlias(StringRef CPU) {
-  if (CPU == "grace")
-    return "neoverse-v2";
-  return CPU;
-}
+StringRef resolveCPUAlias(StringRef CPU);
 
 // Information by Name
 unsigned getDefaultFPU(StringRef CPU, ArchKind AK);
Index: llvm/include/llvm/Support/AArch64TargetParser.def
===================================================================
--- llvm/include/llvm/Support/AArch64TargetParser.def
+++ llvm/include/llvm/Support/AArch64TargetParser.def
@@ -315,3 +315,9 @@
 // Invalid CPU
 AARCH64_CPU_NAME("invalid", INVALID, FK_INVALID, true, AArch64::AEK_INVALID)
 #undef AARCH64_CPU_NAME
+
+#ifndef AARCH64_CPU_ALIAS
+#define AARCH64_CPU_ALIAS(ALIAS,NAME)
+#endif
+AARCH64_CPU_ALIAS("grace", "neoverse-v2")
+#undef AARCH64_CPU_ALIAS
Index: llvm/lib/Support/AArch64TargetParser.cpp
===================================================================
--- llvm/lib/Support/AArch64TargetParser.cpp
+++ llvm/lib/Support/AArch64TargetParser.cpp
@@ -85,6 +85,14 @@
   return true;
 }
 
+StringRef AArch64::resolveCPUAlias(StringRef CPU) {
+  return StringSwitch<StringRef>(CPU)
+#define AARCH64_CPU_ALIAS(ALIAS,NAME)                                          \
+  .Case(ALIAS, NAME)
+#include "../../include/llvm/Support/AArch64TargetParser.def"
+  .Default(CPU);
+}
+
 bool AArch64::getArchFeatures(AArch64::ArchKind AK,
                               std::vector<StringRef> &Features) {
   if (AK == ArchKind::INVALID)
@@ -164,6 +172,9 @@
     if (Arch.ArchID != ArchKind::INVALID)
       Values.push_back(Arch.getName());
   }
+
+  for (const auto &Alias: AArch64CPUAliases)
+    Values.push_back(Alias.getAlias());
 }
 
 bool AArch64::isX18ReservedByDefault(const Triple &TT) {
@@ -198,5 +209,16 @@
     if (CPU == C.getName())
       return C.ArchID;
   }
+
+  // Next, see if it is an alias, and if so, find and return the ArchID of the
+  // CPU it maps to.
+  for (const auto &Alias : AArch64CPUAliases) {
+    if (CPU != Alias.getAlias())
+      continue;
+    for (const auto &C : AArch64CPUNames)
+      if (Alias.getName() == C.getName())
+        return C.ArchID;
+  }
+
   return ArchKind::INVALID;
 }
Index: llvm/unittests/Support/TargetParserTest.cpp
===================================================================
--- llvm/unittests/Support/TargetParserTest.cpp
+++ llvm/unittests/Support/TargetParserTest.cpp
@@ -1295,7 +1295,8 @@
                              AArch64::AEK_LSE | AArch64::AEK_RDM,
                          "8.2-A")));
 
-static constexpr unsigned NumAArch64CPUArchs = 58;
+// Note: number of CPUs includes aliases.
+static constexpr unsigned NumAArch64CPUArchs = 59;
 
 TEST(TargetParserTest, testAArch64CPUArchList) {
   SmallVector<StringRef, NumAArch64CPUArchs> List;