diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index 68fb65b30..56f9b908b 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -18,6 +18,8 @@ set(
   poly1305/poly1305_arm_asm.S
   ../third_party/fiat/asm/fiat_curve25519_adx_mul.S
   ../third_party/fiat/asm/fiat_curve25519_adx_square.S
+  ../third_party/fiat/asm/fiat_p256_adx_mul.S
+  ../third_party/fiat/asm/fiat_p256_adx_sqr.S
 )
 perlasm(CRYPTO_SOURCES aarch64 chacha/chacha-armv8 chacha/asm/chacha-armv8.pl)
 perlasm(CRYPTO_SOURCES aarch64 cipher_extra/chacha20_poly1305_armv8 cipher_extra/asm/chacha20_poly1305_armv8.pl)
diff --git a/crypto/fipsmodule/ec/p256_test.cc b/crypto/fipsmodule/ec/p256_test.cc
new file mode 100644
index 000000000..2af9319b5
--- /dev/null
+++ b/crypto/fipsmodule/ec/p256_test.cc
@@ -0,0 +1,47 @@
+/* Copyright (c) 2023, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <gtest/gtest.h>
+#include "../../internal.h"
+#include "../../test/abi_test.h"
+
+#if !defined(OPENSSL_NO_ASM) && defined(__GNUC__) && defined(__x86_64__) && \
+    defined(SUPPORTS_ABI_TEST)
+extern "C" {
+#include "../../../third_party/fiat/p256_64.h"
+}
+
+TEST(P256Test, AdxMulABI) {
+  static const uint64_t in1[4] = {0}, in2[4] = {0};
+  uint64_t out[4];
+  if (CRYPTO_is_BMI1_capable() && CRYPTO_is_BMI2_capable() &&
+      CRYPTO_is_ADX_capable()) {
+    CHECK_ABI(fiat_p256_adx_mul, out, in1, in2);
+  } else {
+    GTEST_SKIP() << "Can't test ABI of ADX code without ADX";
+  }
+}
+
+#include <assert.h>
+TEST(P256Test, AdxSquareABI) {
+  static const uint64_t in[4] = {0};
+  uint64_t out[4];
+  if (CRYPTO_is_BMI1_capable() && CRYPTO_is_BMI2_capable() &&
+      CRYPTO_is_ADX_capable()) {
+    CHECK_ABI(fiat_p256_adx_sqr, out, in);
+  } else {
+    GTEST_SKIP() << "Can't test ABI of ADX code without ADX";
+  }
+}
+#endif
diff --git a/sources.cmake b/sources.cmake
index d2e15c737..2e7923f7c 100644
--- a/sources.cmake
+++ b/sources.cmake
@@ -38,6 +38,7 @@ set(
   crypto/fipsmodule/cmac/cmac_test.cc
   crypto/fipsmodule/ec/ec_test.cc
   crypto/fipsmodule/ec/p256-nistz_test.cc
+  crypto/fipsmodule/ec/p256_test.cc
   crypto/fipsmodule/ecdsa/ecdsa_test.cc
   crypto/fipsmodule/hkdf/hkdf_test.cc
   crypto/fipsmodule/md5/md5_test.cc
diff --git a/third_party/fiat/asm/fiat_p256_adx_mul.S b/third_party/fiat/asm/fiat_p256_adx_mul.S
new file mode 100644
index 000000000..d7ebd2171
--- /dev/null
+++ b/third_party/fiat/asm/fiat_p256_adx_mul.S
@@ -0,0 +1,178 @@
+#include <openssl/asm_base.h>
+
+#if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) && \
+    (defined(__APPLE__) || defined(__ELF__))
+
+.intel_syntax noprefix
+.text
+#if defined(__APPLE__)
+.private_extern _fiat_p256_adx_mul
+.global _fiat_p256_adx_mul
+_fiat_p256_adx_mul:
+#else
+.type fiat_p256_adx_mul, @function
+.hidden fiat_p256_adx_mul
+.global fiat_p256_adx_mul
+fiat_p256_adx_mul:
+#endif
+
+.cfi_startproc
+_CET_ENDBR
+push rbp
+.cfi_adjust_cfa_offset 8
+.cfi_offset rbp, -16
+mov rbp, rsp
+mov rax, rdx
+mov rdx, [ rsi + 0x0 ]
+test al, al
+mulx r8, rcx, [ rax + 0x0 ]
+mov [ rsp - 0x80 ], rbx
+.cfi_offset rbx, -16-0x80
+mulx rbx, r9, [ rax + 0x8 ]
+mov [ rsp - 0x68 ], r14
+.cfi_offset r14, -16-0x68
+adc r9, r8
+mov [ rsp - 0x60 ], r15
+.cfi_offset r15, -16-0x60
+mulx r15, r14, [ rax + 0x10 ]
+mov [ rsp - 0x78 ], r12
+.cfi_offset r12, -16-0x78
+adc r14, rbx
+mulx r11, r10, [ rax + 0x18 ]
+mov [ rsp - 0x70 ], r13
+.cfi_offset r13, -16-0x70
+adc r10, r15
+mov rdx, [ rsi + 0x8 ]
+mulx rbx, r8, [ rax + 0x0 ]
+adc r11, 0x0
+xor r15, r15
+adcx r8, r9
+adox rbx, r14
+mov [ rsp - 0x58 ], rdi
+mulx rdi, r9, [ rax + 0x8 ]
+adcx r9, rbx
+adox rdi, r10
+mulx rbx, r14, [ rax + 0x10 ]
+adcx r14, rdi
+adox rbx, r11
+mulx r13, r12, [ rax + 0x18 ]
+adcx r12, rbx
+mov rdx, 0x100000000
+mulx r11, r10, rcx
+adox r13, r15
+adcx r13, r15
+xor rdi, rdi
+adox r10, r8
+mulx r8, rbx, r10
+adox r11, r9
+adcx rbx, r11
+adox r8, r14
+mov rdx, 0xffffffff00000001
+mulx r9, r15, rcx
+adcx r15, r8
+adox r9, r12
+mulx r14, rcx, r10
+mov rdx, [ rsi + 0x10 ]
+mulx r10, r12, [ rax + 0x8 ]
+adcx rcx, r9
+adox r14, r13
+mulx r11, r13, [ rax + 0x0 ]
+mov r9, rdi
+adcx r14, r9
+adox rdi, rdi
+adc rdi, 0x0
+xor r9, r9
+adcx r13, rbx
+adox r11, r15
+mov rdx, [ rsi + 0x10 ]
+mulx r15, r8, [ rax + 0x10 ]
+adox r10, rcx
+mulx rcx, rbx, [ rax + 0x18 ]
+mov rdx, [ rsi + 0x18 ]
+adcx r12, r11
+mulx rsi, r11, [ rax + 0x8 ]
+adcx r8, r10
+adox r15, r14
+adcx rbx, r15
+adox rcx, r9
+adcx rcx, r9
+mulx r15, r10, [ rax + 0x0 ]
+add rcx, rdi
+mov r14, r9
+adc r14, 0
+xor r9, r9
+adcx r10, r12
+adox r15, r8
+adcx r11, r15
+adox rsi, rbx
+mulx r8, r12, [ rax + 0x10 ]
+adox r8, rcx
+mulx rcx, rbx, [ rax + 0x18 ]
+adcx r12, rsi
+adox rcx, r9
+mov rdx, 0x100000000
+adcx rbx, r8
+adc rcx, 0
+mulx rdi, r15, r13
+xor rax, rax
+adcx rcx, r14
+adc rax, 0
+xor r9, r9
+adox r15, r10
+mulx r14, r10, r15
+adox rdi, r11
+mov rdx, 0xffffffff00000001
+adox r14, r12
+adcx r10, rdi
+mulx r12, r11, r13
+adcx r11, r14
+adox r12, rbx
+mulx rbx, r13, r15
+adcx r13, r12
+adox rbx, rcx
+mov r8, r9
+adox rax, r9
+adcx r8, rbx
+adc rax, 0x0
+mov rcx, rax
+mov r15, 0xffffffffffffffff
+mov rdi, r10
+sub rdi, r15
+mov r14, 0xffffffff
+mov r12, r11
+sbb r12, r14
+mov rbx, r13
+sbb rbx, r9
+mov rax, rax
+mov rax, r8
+sbb rax, rdx
+sbb rcx, r9
+cmovc rdi, r10
+mov r10, [ rsp - 0x58 ]
+cmovc rbx, r13
+mov r13, [ rsp - 0x70 ]
+.cfi_restore r13
+cmovc r12, r11
+cmovc rax, r8
+mov [ r10 + 0x10 ], rbx
+mov rbx, [ rsp - 0x80 ]
+.cfi_restore rbx
+mov [ r10 + 0x0 ], rdi
+mov [ r10 + 0x8 ], r12
+mov [ r10 + 0x18 ], rax
+mov r12, [ rsp - 0x78 ]
+.cfi_restore r12
+mov r14, [ rsp - 0x68 ]
+.cfi_restore r14
+mov r15, [ rsp - 0x60 ]
+.cfi_restore r15
+pop rbp
+.cfi_restore rbp
+.cfi_adjust_cfa_offset -8
+ret
+.cfi_endproc
+#if defined(__ELF__)
+.size fiat_p256_adx_mul, .-fiat_p256_adx_mul
+#endif
+
+#endif
diff --git a/third_party/fiat/asm/fiat_p256_adx_sqr.S b/third_party/fiat/asm/fiat_p256_adx_sqr.S
new file mode 100644
index 000000000..cca269f52
--- /dev/null
+++ b/third_party/fiat/asm/fiat_p256_adx_sqr.S
@@ -0,0 +1,167 @@
+#include <openssl/asm_base.h>
+
+#if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) && \
+    (defined(__APPLE__) || defined(__ELF__))
+
+.intel_syntax noprefix
+.text
+#if defined(__APPLE__)
+.private_extern _fiat_p256_adx_sqr
+.global _fiat_p256_adx_sqr
+_fiat_p256_adx_sqr:
+#else
+.type fiat_p256_adx_sqr, @function
+.hidden fiat_p256_adx_sqr
+.global fiat_p256_adx_sqr
+fiat_p256_adx_sqr:
+#endif
+
+.cfi_startproc
+_CET_ENDBR
+push rbp
+.cfi_adjust_cfa_offset 8
+.cfi_offset rbp, -16
+mov rbp, rsp
+mov rdx, [ rsi + 0x0 ]
+mulx r10, rax, [ rsi + 0x18 ]
+mulx rcx, r11, rdx
+mulx r9, r8, [ rsi + 0x8 ]
+mov [ rsp - 0x80 ], rbx
+.cfi_offset rbx, -16-0x80
+xor rbx, rbx
+adox r8, r8
+mov [ rsp - 0x78 ], r12
+.cfi_offset r12, -16-0x78
+mulx r12, rbx, [ rsi + 0x10 ]
+mov rdx, [ rsi + 0x8 ]
+mov [ rsp - 0x70 ], r13
+.cfi_offset r13, -16-0x70
+mov [ rsp - 0x68 ], r14
+.cfi_offset r14, -16-0x68
+mulx r14, r13, rdx
+mov [ rsp - 0x60 ], r15
+.cfi_offset r15, -16-0x60
+mov [ rsp - 0x58 ], rdi
+mulx rdi, r15, [ rsi + 0x10 ]
+adcx r12, r15
+mov [ rsp - 0x50 ], r11
+mulx r11, r15, [ rsi + 0x18 ]
+adcx r10, rdi
+mov rdi, 0x0
+adcx r11, rdi
+clc
+adcx rbx, r9
+adox rbx, rbx
+adcx rax, r12
+adox rax, rax
+adcx r15, r10
+adox r15, r15
+mov rdx, [ rsi + 0x10 ]
+mulx r12, r9, [ rsi + 0x18 ]
+adcx r9, r11
+adcx r12, rdi
+mulx r11, r10, rdx
+clc
+adcx rcx, r8
+adcx r13, rbx
+adcx r14, rax
+adox r9, r9
+adcx r10, r15
+mov rdx, [ rsi + 0x18 ]
+mulx rbx, r8, rdx
+adox r12, r12
+adcx r11, r9
+mov rsi, [ rsp - 0x50 ]
+adcx r8, r12
+mov rax, 0x100000000
+mov rdx, rax
+mulx r15, rax, rsi
+adcx rbx, rdi
+adox rbx, rdi
+xor r9, r9
+adox rax, rcx
+adox r15, r13
+mulx rcx, rdi, rax
+adcx rdi, r15
+adox rcx, r14
+mov rdx, 0xffffffff00000001
+mulx r14, r13, rsi
+adox r14, r10
+adcx r13, rcx
+mulx r12, r10, rax
+adox r12, r11
+mov r11, r9
+adox r11, r8
+adcx r10, r14
+mov r8, r9
+adcx r8, r12
+mov rax, r9
+adcx rax, r11
+mov r15, r9
+adox r15, rbx
+mov rdx, 0x100000000
+mulx rcx, rbx, rdi
+mov r14, r9
+adcx r14, r15
+mov r12, r9
+adox r12, r12
+adcx r12, r9
+adox rbx, r13
+mulx r11, r13, rbx
+mov r15, 0xffffffff00000001
+mov rdx, r15
+mulx rsi, r15, rbx
+adox rcx, r10
+adox r11, r8
+mulx r8, r10, rdi
+adcx r13, rcx
+adox r8, rax
+adcx r10, r11
+adox rsi, r14
+mov rdi, r12
+mov rax, r9
+adox rdi, rax
+adcx r15, r8
+mov r14, rax
+adcx r14, rsi
+adcx rdi, r9
+dec r9
+mov rbx, r13
+sub rbx, r9
+mov rcx, 0xffffffff
+mov r11, r10
+sbb r11, rcx
+mov r8, r15
+sbb r8, rax
+mov rsi, r14
+sbb rsi, rdx
+sbb rdi, rax
+cmovc rbx, r13
+cmovc r8, r15
+cmovc r11, r10
+cmovc rsi, r14
+mov rdi, [ rsp - 0x58 ]
+mov [ rdi + 0x18 ], rsi
+mov [ rdi + 0x0 ], rbx
+mov [ rdi + 0x8 ], r11
+mov [ rdi + 0x10 ], r8
+mov rbx, [ rsp - 0x80 ]
+.cfi_restore rbx
+mov r12, [ rsp - 0x78 ]
+.cfi_restore r12
+mov r13, [ rsp - 0x70 ]
+.cfi_restore r13
+mov r14, [ rsp - 0x68 ]
+.cfi_restore r14
+mov r15, [ rsp - 0x60 ]
+.cfi_restore r15
+pop rbp
+.cfi_restore rbp
+.cfi_adjust_cfa_offset -8
+ret
+.cfi_endproc
+#if defined(__ELF__)
+.size fiat_p256_adx_sqr, .-fiat_p256_adx_sqr
+#endif
+
+#endif
diff --git a/third_party/fiat/p256_64.h b/third_party/fiat/p256_64.h
index c77263843..a691407b6 100644
--- a/third_party/fiat/p256_64.h
+++ b/third_party/fiat/p256_64.h
@@ -1,3 +1,9 @@
+#include "../../crypto/internal.h"
+#if !defined(OPENSSL_NO_ASM) && defined(__GNUC__) && defined(__x86_64__)
+void fiat_p256_adx_mul(uint64_t*, const uint64_t*, const uint64_t*);
+void fiat_p256_adx_sqr(uint64_t*, const uint64_t*);
+#endif
+
 /* Autogenerated: 'src/ExtractionOCaml/word_by_word_montgomery' --inline --static --use-value-barrier p256 64 '2^256 - 2^224 + 2^192 + 2^96 - 1' mul square add sub opp from_montgomery to_montgomery nonzero selectznz to_bytes from_bytes one msat divstep divstep_precomp */
 /* curve description: p256 */
 /* machine_wordsize = 64 (from "64") */
@@ -165,6 +171,13 @@ static FIAT_P256_FIAT_INLINE void fiat_p256_cmovznz_u64(uint64_t* out1, fiat_p25
  *
  */
 static FIAT_P256_FIAT_INLINE void fiat_p256_mul(fiat_p256_montgomery_domain_field_element out1, const fiat_p256_montgomery_domain_field_element arg1, const fiat_p256_montgomery_domain_field_element arg2) {
+#if !defined(OPENSSL_NO_ASM) && defined(__GNUC__) && defined(__x86_64__)
+  if (CRYPTO_is_BMI1_capable() && CRYPTO_is_BMI2_capable() &&
+    CRYPTO_is_ADX_capable()) {
+      fiat_p256_adx_mul(out1, arg1, arg2);
+      return;
+  }
+#endif
   uint64_t x1;
   uint64_t x2;
   uint64_t x3;
@@ -472,6 +485,13 @@ static FIAT_P256_FIAT_INLINE void fiat_p256_mul(fiat_p256_montgomery_domain_fiel
  *
  */
 static FIAT_P256_FIAT_INLINE void fiat_p256_square(fiat_p256_montgomery_domain_field_element out1, const fiat_p256_montgomery_domain_field_element arg1) {
+#if !defined(OPENSSL_NO_ASM) && defined(__GNUC__) && defined(__x86_64__)
+  if (CRYPTO_is_BMI1_capable() && CRYPTO_is_BMI2_capable() &&
+    CRYPTO_is_ADX_capable()) {
+      fiat_p256_adx_sqr(out1, arg1);
+      return;
+  }
+#endif
   uint64_t x1;
   uint64_t x2;
   uint64_t x3;