diff --git a/clang/test/Driver/aarch64-cssc.c b/clang/test/Driver/aarch64-cssc.c
--- a/clang/test/Driver/aarch64-cssc.c
+++ b/clang/test/Driver/aarch64-cssc.c
@@ -1,15 +1,17 @@
 // Test that target feature cssc is implemented and available correctly
-// RUN: %clang -### -target aarch64-none-none-eabi                         %s 2>&1 | FileCheck %s --check-prefix=ABSENT_CSSC
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.8-a+cssc   %s 2>&1 | FileCheck %s
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.9-a        %s 2>&1 | FileCheck %s --check-prefix=ABSENT_CSSC
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.8-a+cssc   %s 2>&1 | FileCheck %s
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.9-a+nocssc %s 2>&1 | FileCheck %s --check-prefix=NO_CSSC
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.3-a+cssc   %s 2>&1 | FileCheck %s
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.4-a        %s 2>&1 | FileCheck %s --check-prefix=ABSENT_CSSC
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.3-a+cssc   %s 2>&1 | FileCheck %s
-// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.4-a+nocssc %s 2>&1 | FileCheck %s --check-prefix=NO_CSSC
+// FEAT_CSSC is a required part of v8.9a/v9.4a and optional from v8.7a/v9.3a onwards.
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi                         %s 2>&1 | FileCheck %s --check-prefix=ABSENT_CSSC
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv8.7-a+cssc   %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv8.9-a        %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv8.9-a+cssc   %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv8.9-a+nocssc %s 2>&1 | FileCheck %s --check-prefix=NO_CSSC
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv9.2-a+cssc   %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv9.4-a        %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv9.4-a+cssc   %s 2>&1 | FileCheck %s
+// RUN: %clang -S -o - -emit-llvm -target aarch64-none-none-eabi -march=armv9.4-a+nocssc %s 2>&1 | FileCheck %s --check-prefix=NO_CSSC
 
-// CHECK: "-target-feature" "+cssc"
-// NO_CSSC: "-target-feature" "-cssc"
-// ABSENT_CSSC-NOT: "-target-feature" "+cssc"
-// ABSENT_CSSC-NOT: "-target-feature" "-cssc"
+// CHECK: "target-features"="{{.*}},+cssc
+// NO_CSSC: "target-features"="{{.*}},-cssc
+// ABSENT_CSSC-NOT: "target-features"="{{.*}},+cssc
+// ABSENT_CSSC-NOT: "target-features"="{{.*}},-cssc
+void test() {}
diff --git a/llvm/include/llvm/TargetParser/AArch64TargetParser.h b/llvm/include/llvm/TargetParser/AArch64TargetParser.h
--- a/llvm/include/llvm/TargetParser/AArch64TargetParser.h
+++ b/llvm/include/llvm/TargetParser/AArch64TargetParser.h
@@ -315,12 +315,12 @@
 inline constexpr ArchInfo ARMV8_6A  = { VersionTuple{8, 6}, AProfile, "armv8.6-a", "+v8.6a", (BaseNoCrypto | AArch64::AEK_SM4 | AArch64::AEK_SHA3 | AArch64::AEK_BF16 | AArch64::AEK_SHA2 | AArch64::AEK_AES | AArch64::AEK_I8MM)};
 inline constexpr ArchInfo ARMV8_7A  = { VersionTuple{8, 7}, AProfile, "armv8.7-a", "+v8.7a", (ARMV8_6A.DefaultExts)};
 inline constexpr ArchInfo ARMV8_8A  = { VersionTuple{8, 8}, AProfile, "armv8.8-a", "+v8.8a", (ARMV8_7A.DefaultExts | AArch64::AEK_MOPS | AArch64::AEK_HBC)};
-inline constexpr ArchInfo ARMV8_9A  = { VersionTuple{8, 9}, AProfile, "armv8.9-a", "+v8.9a", (ARMV8_8A.DefaultExts)};
+inline constexpr ArchInfo ARMV8_9A  = { VersionTuple{8, 9}, AProfile, "armv8.9-a", "+v8.9a", (ARMV8_8A.DefaultExts | AArch64::AEK_SPECRES2 | AArch64::AEK_CSSC | AArch64::AEK_RASv2)};
 inline constexpr ArchInfo ARMV9A    = { VersionTuple{9, 0}, AProfile, "armv9-a", "+v9a", (BaseNoCrypto | AArch64::AEK_FP16 | AArch64::AEK_SVE | AArch64::AEK_SVE2)};
 inline constexpr ArchInfo ARMV9_1A  = { VersionTuple{9, 1}, AProfile, "armv9.1-a", "+v9.1a", (ARMV9A.DefaultExts | AArch64::AEK_BF16 | AArch64::AEK_I8MM)};
 inline constexpr ArchInfo ARMV9_2A  = { VersionTuple{9, 2}, AProfile, "armv9.2-a", "+v9.2a", (ARMV9_1A.DefaultExts)};
 inline constexpr ArchInfo ARMV9_3A  = { VersionTuple{9, 3}, AProfile, "armv9.3-a", "+v9.3a", (ARMV9_2A.DefaultExts | AArch64::AEK_MOPS | AArch64::AEK_HBC)};
-inline constexpr ArchInfo ARMV9_4A  = { VersionTuple{9, 4}, AProfile, "armv9.4-a", "+v9.4a", (ARMV9_3A.DefaultExts)};
+inline constexpr ArchInfo ARMV9_4A  = { VersionTuple{9, 4}, AProfile, "armv9.4-a", "+v9.4a", (ARMV9_3A.DefaultExts | AArch64::AEK_SPECRES2 | AArch64::AEK_CSSC | AArch64::AEK_RASv2)};
 // For v8-R, we do not enable crypto and align with GCC that enables a more minimal set of optional architecture extensions.
 inline constexpr ArchInfo ARMV8R    = { VersionTuple{8, 0}, RProfile, "armv8-r", "+v8r", ((BaseNoCrypto ^ AArch64::AEK_LSE) | AArch64::AEK_SSBS | AArch64::AEK_FP16 | AArch64::AEK_FP16FML | AArch64::AEK_SB), };
 // clang-format on