Adding guards to compile w/o AX512.

Author: armfazh

CMakeLists.txt

@@ -8,8 +8,14 @@ set(CMAKE_C_STANDARD 99)
 set(EXECUTABLE_OUTPUT_PATH ../bin)
 set(LIBRARY_OUTPUT_PATH ../lib)
 
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror -Wall -Wextra -O3 -pedantic -std=c99 -m64 -mavx2 -mbmi2 -mavx512f -mavx512bw -march=native -mtune=native")
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror -Wall -Wextra -O3 -pedantic -std=c99 -m64 -mavx2 -mbmi2 -march=native -mtune=native")
+
+option(ENABLE_AVX512 "Enables AVX512 code" OFF)
+if(ENABLE_AVX512)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mavx512f -mavx512bw")
+    add_compile_definitions(ENABLED_AVX512)
+endif(ENABLE_AVX512)
 
 add_subdirectory(third_party)
 add_subdirectory(src)

README.md

@@ -1,6 +1,6 @@
 # FLD ECC AVX2
 
-This is a mathematical software library for computing the Edwards Digital Signature Algorithm (EdDSA) and the Diffie-Hellman functions X25519 and X448. The library is optimized with the Intel Advanced Vector eXtensions version 2 (AVX2) and is derived from a research project.
+This is a mathematical software library for computing the Edwards Digital Signature Algorithm (EdDSA) and the Diffie-Hellman functions X25519 and X448. The library is optimized with the Intel Advanced Vector eXtensions AVX2 and AVX512 product of this research project.
 
 ```bibtex
 @article{fld_ecc_avx2,
@@ -31,6 +31,14 @@ To compile use:
     $ make all
 ```
 
+#### Enabling AVX512
+
+Use AVX512 extensions to perform two X25519 operations simultaneously.
+```bash
+    $ cmake .. -DENABLE_AVX512=ON
+    $ make all
+```
+
 ### Benchmarks
 
 For running the benchmark program use:

bench/bench_ecdh.c

@@ -20,6 +20,7 @@ static void bench_ecdh(const X_ECDH* ecdh)
     ecdh->freeKey(shared_secret);
 }
 
+#if defined(ENABLED_AVX512)
 static void bench_x25519_avx512()
 {
     struct X25519_KEY_x2 ss, sk, pk;
@@ -37,6 +38,7 @@ static void bench_x25519_avx512()
         X25519_AVX512.randKey(pk.k1);
         , shared, X25519_AVX512.shared(&ss, &sk, &pk));
 }
+#endif /* defined(ENABLED_AVX512) */
 
 void bench_x25519(void)
 {
@@ -45,8 +47,10 @@ void bench_x25519(void)
     bench_ecdh(&X25519_x64);
     printf("======  X25519 AVX2 ======\n");
     bench_ecdh(&X25519_AVX2);
+#if defined(ENABLED_AVX512)
     printf("====== X25519 AVX512 ====\n");
     bench_x25519_avx512();
+#endif /* defined(ENABLED_AVX512) */
 }
 
 void bench_x448(void)

include/faz_ecdh_avx2.h

@@ -97,7 +97,8 @@ typedef ALIGN uint8_t X25519_KEY[ECDH25519_KEY_SIZE_BYTES];
 #define ECDH448_KEY_SIZE_BYTES 56
 typedef ALIGN uint8_t X448_KEY[ECDH448_KEY_SIZE_BYTES];
 
-ALIGN struct X25519_KEY_x2 {
+#if defined(ENABLED_AVX512)
+struct ALIGN X25519_KEY_x2 {
     X25519_KEY k0, k1;
 };
 
@@ -124,6 +125,7 @@ typedef struct _struct_DiffieHellmanXFunction_x2 {
 } X_ECDH_x2;
 
 extern const X_ECDH_x2 X25519_AVX512;
+#endif /* defined(ENABLED_AVX512) */
 
 #ifdef __cplusplus
 } /* namespace ecdh */

include/simd_avx2.h

@@ -1,21 +1,3 @@
-/**
- * Copyright 2017 Armando Faz Hernández
- * This file is part of faz_ecc_avx2.
- *
- * faz_ecc_avx2 is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * faz_ecc_avx2 is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with faz_ecc_avx2.  If not, see <http://www.gnu.org/licenses/>.
- */
-
 /**
  * Copyright 2017 Armando Faz Hernández
  * This file is part of faz_ecc_avx2.
@@ -112,6 +94,7 @@
       : /* in   */ "r"(Y)      \
       : /* regs */);
 
+#if defined(ENABLED_AVX512)
 #define ZERO_x2             _mm512_setzero_si512()
 #define LOAD_x2(X)          _mm512_load_si512((__m512i*) X)
 #define STORE_x2(X, Y)      _mm512_store_si512((__m512i*) X, Y)
@@ -134,5 +117,6 @@
 #define SET64_x2(X7,X6,X5,X4,X3,X2,X1,X0) _mm512_set_epi64(X7,X6,X5,X4,X3,X2,X1,X0)
 #define EXTR_x2(X,Y)        _mm512_extracti64x4_epi64(X,Y)
 #define INSR_x2(X,Y,Z)      _mm512_inserti64x4(X,Y,Z)
+#endif /* defined(ENABLED_AVX512) */
 
 #endif /* SIMD_AVX2_H */

src/dh255.c

@@ -16,7 +16,7 @@
  * along with faz_ecc_avx2.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if defined(DH255) || 1
+#if defined(DH255)
 
 #include "faz_ecdh_avx2.h"
 
@@ -30,6 +30,7 @@ extern "C" {
 
 #include "ladder255.c"
 
+#if defined(ENABLED_AVX512)
 const X_ECDH_x2 X25519_AVX512 = {
     .keygen = x25519_keygen_avx512,
     .shared = x25519_shared_avx512,
@@ -39,6 +40,7 @@ const X_ECDH_x2 X25519_AVX512 = {
     .randKey  = randX25519_Key,
     .printKey  = printX25519_Key,
 };
+#endif /* defined(ENABLED_AVX512) */
 
 const X_ECDH X25519_AVX2 = {
     .keygen = x25519_keygen_avx2,

src/eltfp25519_2w_redradix_x2.c

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017 Armando Faz Hernández
+ * Copyright 2025 Armando Faz Hernández
  * This file is part of faz_ecc_avx2.
  *
  * faz_ecc_avx2 is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
  * along with faz_ecc_avx2.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if defined(FP255) || 1
+#if defined(FP255) && defined(ENABLED_AVX512)
 
 #define FN(NAME) SUFFIX(NAME, 2, redradix_x2)
 #define DECL(RETURN, NAME) SCOPE RETURN FN(NAME)

src/fp255.c

@@ -16,7 +16,7 @@
  * along with faz_ecc_avx2.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if defined(FP255) || 1
+#if defined(FP255)
 
 #include "faz_fp_avx2.h"
 #include "simd_avx2.h"
@@ -35,7 +35,9 @@ extern "C" {
 #include "eltfp25519_1w_redradix.c"
 #include "eltfp25519_2w_redradix.c"
 #include "eltfp25519_4w_redradix.c"
+#if defined(ENABLED_AVX512)
 #include "eltfp25519_2w_redradix_x2.c"
+#endif /* defined(ENABLED_AVX512) */
 
 const PrimeField Fp25519 = {
     ._1w_full = {
@@ -136,6 +138,7 @@ const PrimeField Fp25519 = {
             .compressfast = SUFFIX(compressfast,2,redradix),
         },
     },
+#if defined(ENABLED_AVX512)
     ._2w_red_x2 = {
         .arith = {
             .add = SUFFIX(add,2,redradix_x2),
@@ -169,6 +172,7 @@ const PrimeField Fp25519 = {
             .compressfast = SUFFIX(compressfast,2,redradix_x2),
         },
     },
+#endif /* defined(ENABLED_AVX512) */
     ._4w_red = {
         .arith = {
             .add = SUFFIX(add,4,redradix),