diff --git a/gcc/config/aarch64/aarch64-arches.def b/gcc/config/aarch64/aarch64-arches.def
index 6b9a19c490b..1fe6b796001 100644
--- a/gcc/config/aarch64/aarch64-arches.def
+++ b/gcc/config/aarch64/aarch64-arches.def
@@ -39,10 +39,12 @@ AARCH64_ARCH("armv8.5-a",     generic_armv8_a,   V8_5A,     8,  (V8_4A, SB, SSBS
 AARCH64_ARCH("armv8.6-a",     generic_armv8_a,   V8_6A,     8,  (V8_5A, I8MM, BF16))
 AARCH64_ARCH("armv8.7-a",     generic_armv8_a,   V8_7A,     8,  (V8_6A, LS64))
 AARCH64_ARCH("armv8.8-a",     generic_armv8_a,   V8_8A,     8,  (V8_7A, MOPS))
+AARCH64_ARCH("armv8.9-a",     generic_armv8_a,   V8_9A,     8,  (V8_8A))
 AARCH64_ARCH("armv8-r",       generic_armv8_a,   V8R  ,     8,  (V8_4A))
 AARCH64_ARCH("armv9-a",       generic_armv9_a,   V9A  ,     9,  (V8_5A, SVE2))
 AARCH64_ARCH("armv9.1-a",     generic_armv9_a,   V9_1A,     9,  (V8_6A, V9A))
 AARCH64_ARCH("armv9.2-a",     generic_armv9_a,   V9_2A,     9,  (V8_7A, V9_1A))
 AARCH64_ARCH("armv9.3-a",     generic_armv9_a,   V9_3A,     9,  (V8_8A, V9_2A))
+AARCH64_ARCH("armv9.4-a",     generic_armv9_a,   V9_4A,     9,  (V8_9A, V9_3A))
 
 #undef AARCH64_ARCH
diff --git a/gcc/config/aarch64/aarch64-c.cc b/gcc/config/aarch64/aarch64-c.cc
index be8b7236cf9..cacf8e8ed25 100644
--- a/gcc/config/aarch64/aarch64-c.cc
+++ b/gcc/config/aarch64/aarch64-c.cc
@@ -206,6 +206,7 @@ aarch64_update_cpp_builtins (cpp_reader *pfile)
   aarch64_def_or_undef (TARGET_LS64,
 			"__ARM_FEATURE_LS64", pfile);
   aarch64_def_or_undef (AARCH64_ISA_RCPC, "__ARM_FEATURE_RCPC", pfile);
+  aarch64_def_or_undef (TARGET_D128, "__ARM_FEATURE_SYSREG128", pfile);
 
   /* Not for ACLE, but required to keep "float.h" correct if we switch
      target between implementations that do or do not support ARMv8.2-A
diff --git a/gcc/config/aarch64/aarch64-option-extensions.def b/gcc/config/aarch64/aarch64-option-extensions.def
index 825f3bf7758..da31f7c32d1 100644
--- a/gcc/config/aarch64/aarch64-option-extensions.def
+++ b/gcc/config/aarch64/aarch64-option-extensions.def
@@ -151,4 +151,8 @@ AARCH64_OPT_EXTENSION("mops", MOPS, (), (), (), "")
 
 AARCH64_OPT_EXTENSION("cssc", CSSC, (), (), (), "cssc")
 
+AARCH64_OPT_EXTENSION("d128", D128, (), (), (), "d128")
+
+AARCH64_OPT_EXTENSION("the", THE, (), (), (), "the")
+
 #undef AARCH64_OPT_EXTENSION
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index efe2036537e..5f0486cb128 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -219,13 +219,17 @@ enum class aarch64_feature : unsigned char {
 #define AARCH64_ISA_PAUTH	   (aarch64_isa_flags & AARCH64_FL_PAUTH)
 #define AARCH64_ISA_V8_7A	   (aarch64_isa_flags & AARCH64_FL_V8_7A)
 #define AARCH64_ISA_V8_8A	   (aarch64_isa_flags & AARCH64_FL_V8_8A)
+#define AARCH64_ISA_V8_9A	   (aarch64_isa_flags & AARCH64_FL_V8_9A)
 #define AARCH64_ISA_V9A		   (aarch64_isa_flags & AARCH64_FL_V9A)
 #define AARCH64_ISA_V9_1A          (aarch64_isa_flags & AARCH64_FL_V9_1A)
 #define AARCH64_ISA_V9_2A          (aarch64_isa_flags & AARCH64_FL_V9_2A)
 #define AARCH64_ISA_V9_3A          (aarch64_isa_flags & AARCH64_FL_V9_3A)
+#define AARCH64_ISA_V9_4A          (aarch64_isa_flags & AARCH64_FL_V9_4A)
 #define AARCH64_ISA_MOPS	   (aarch64_isa_flags & AARCH64_FL_MOPS)
 #define AARCH64_ISA_LS64	   (aarch64_isa_flags & AARCH64_FL_LS64)
 #define AARCH64_ISA_CSSC	   (aarch64_isa_flags & AARCH64_FL_CSSC)
+#define AARCH64_ISA_D128	   (aarch64_isa_flags & AARCH64_FL_D128)
+#define AARCH64_ISA_THE		   (aarch64_isa_flags & AARCH64_FL_THE)
 
 /* AARCH64_FL options necessary for system register implementation.  */
 
@@ -388,6 +392,17 @@ enum class aarch64_feature : unsigned char {
 /* ARMv8.1-A Adv.SIMD support.  */
 #define TARGET_SIMD_RDMA (TARGET_SIMD && AARCH64_ISA_RDMA)
 
+/* Armv9.4-A features.  */
+#define TARGET_ARMV9_4 (AARCH64_ISA_V9_4A)
+
+/*  128-bit System Registers and Instructions from Armv9.4-a are enabled
+    through +d128.  */
+#define TARGET_D128 (AARCH64_ISA_D128)
+
+/*  Armv8.9-A/9.4-A Translation Hardening Extension system registers are
+    enabled through +the.  */
+#define TARGET_THE (AARCH64_ISA_THE)
+
 /* Standard register usage.  */
 
 /* 31 64-bit general purpose registers R0-R30:
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 7666de1e9b2..c76205bf6e8 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -20801,10 +20801,12 @@ and the features that they enable by default:
 @item @samp{armv8.6-a} @tab Armv8.6-A @tab @samp{armv8.5-a}, @samp{+bf16}, @samp{+i8mm}
 @item @samp{armv8.7-a} @tab Armv8.7-A @tab @samp{armv8.6-a}, @samp{+ls64}
 @item @samp{armv8.8-a} @tab Armv8.8-a @tab @samp{armv8.7-a}, @samp{+mops}
+@item @samp{armv8.9-a} @tab Armv8.9-a @tab @samp{armv8.8-a}
 @item @samp{armv9-a} @tab Armv9-A @tab @samp{armv8.5-a}, @samp{+sve}, @samp{+sve2}
 @item @samp{armv9.1-a} @tab Armv9.1-A @tab @samp{armv9-a}, @samp{+bf16}, @samp{+i8mm}
 @item @samp{armv9.2-a} @tab Armv9.2-A @tab @samp{armv9.1-a}, @samp{+ls64}
 @item @samp{armv9.3-a} @tab Armv9.3-A @tab @samp{armv9.2-a}, @samp{+mops}
+@item @samp{armv9.4-a} @tab Armv9.4-A @tab @samp{armv9.3-a}
 @item @samp{armv8-r} @tab Armv8-R @tab @samp{armv8-r}
 @end multitable
 
@@ -21107,6 +21109,10 @@ Enable the Flag Manipulation instructions Extension.
 Enable the Pointer Authentication Extension.
 @item cssc
 Enable the Common Short Sequence Compression instructions.
+@item d128
+Enable support for 128-bit system register read/write instructions.
+@item the
+Enable support for Armv8.9-a/9.4-a translation hardening extension.
 
 @end table
 
