CPU: remove AVX code, switch to __builtin for AES detection (#1959)

* [cpu] remove avx detect and code blocks, try to switch to __builtin
* [cpu] use __builtin_* only on x86 systems
* [cpu] perform check in separate function
* [cpu] set AES definition on MSVC
* update x86 and aes support checks at compile time
* [cmake] update comment about AES on MSVC

.editorconfig

@@ -34,3 +34,6 @@ trim_trailing_whitespace = false
 [*.yml]
 indent_style = space
 indent_size = 2
+
+[*.patch]
+trim_trailing_whitespace = false

build/CMakeLists.txt

@@ -197,14 +197,11 @@ endif()
 
 # Note: AES-NI and AVX is available on x86-based CPU's.
 # Here also ARM64 implementation, but currently we don't support it.
-# MSVC is not supported.
-if(MSVC)
-  message(STATUS "AES-NI is not supported on MSVC, option was disabled")
-  set(WITH_AESNI OFF)
-endif()
-
+# MSVC is not supported due to different ASM processing, so we hope OpenSSL has its own checks to run optimized code.
 if(WITH_AESNI AND (ARCHITECTURE MATCHES "x86_64" OR ARCHITECTURE MATCHES "i386"))
+  if(NOT MSVC)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -maes")
+  endif()
   add_definitions(-D__AES__)
 endif()
 

contrib/i2pd.conf

@@ -280,8 +280,6 @@ verify = true
 [cpuext]
 ## Use CPU AES-NI instructions set when work with cryptography when available (default: true)
 # aesni = true
-## Use CPU AVX instructions set when work with cryptography when available (default: true)
-# avx = true
 ## Force usage of CPU instructions set, even if they not found (default: false)
 ## DO NOT TOUCH that option if you really don't know what are you doing!
 # force = false

daemon/Daemon.cpp

@@ -150,12 +150,11 @@ namespace util
 
 		bool precomputation; i2p::config::GetOption("precomputation.elgamal", precomputation);
 		bool aesni; i2p::config::GetOption("cpuext.aesni", aesni);
-		bool avx; i2p::config::GetOption("cpuext.avx", avx);
 		bool forceCpuExt; i2p::config::GetOption("cpuext.force", forceCpuExt);
 		bool ssu; i2p::config::GetOption("ssu", ssu);
 		if (!ssu && i2p::config::IsDefault ("precomputation.elgamal"))
 			precomputation = false; // we don't elgamal table if no ssu, unless it's specified explicitly
-		i2p::crypto::InitCrypto (precomputation, aesni, avx, forceCpuExt);
+		i2p::crypto::InitCrypto (precomputation, aesni, forceCpuExt);
 
 		i2p::transport::InitAddressFromIface (); // get address4/6 from interfaces
 

libi2pd/CPU.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2023, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -7,52 +7,52 @@
 */
 
 #include "CPU.h"
-#if defined(__x86_64__) || defined(__i386__)
-#include <cpuid.h>
-#endif
 #include "Log.h"
 
+#if defined(_MSC_VER)
+#include <intrin.h>
+
 #ifndef bit_AES
 	#define bit_AES (1 << 25)
 #endif
-#ifndef bit_AVX
-#define bit_AVX (1 << 28)
 #endif
 
-
 namespace i2p
 {
 namespace cpu
 {
 	bool aesni = false;
-	bool avx = false;
 
-	void Detect(bool AesSwitch, bool AvxSwitch, bool force)
+	inline bool cpu_support_aes()
 	{
-#if defined(__x86_64__) || defined(__i386__)
-		int info[4];
-		__cpuid(0, info[0], info[1], info[2], info[3]);
-		if (info[0] >= 0x00000001) {
-			__cpuid(0x00000001, info[0], info[1], info[2], info[3]);
-#if defined (_WIN32) && (WINVER == 0x0501) // WinXP
-			if (AesSwitch && force) { // only if forced
+#if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_IX86) || defined(__i386__))
+#if defined(_MSC_VER)
+		int cpu_info[4];
+		__cpuid(cpu_info, 1);
+		return ((cpu_info[2] & bit_AES) != 0);
+#elif defined(__clang__)
+#if __clang_major__ >= 6
+		__builtin_cpu_init();
+#endif
+		return __builtin_cpu_supports("aes");
+#elif defined(__GNUC__)
+		__builtin_cpu_init();
+		return __builtin_cpu_supports("aes");
 #else
-			if ((info[2] & bit_AES && AesSwitch) || (AesSwitch && force)) {
+		return false;
 #endif
-				aesni = true;
-			}
-#if defined (_WIN32) && (WINVER == 0x0501) // WinXP
-			if (AvxSwitch && force) { // only if forced
 #else
-			if ((info[2] & bit_AVX && AvxSwitch) || (AvxSwitch && force)) {
+		return false;
 #endif
-				avx = true;
 	}
+
+	void Detect(bool AesSwitch, bool force)
+	{
+		if ((cpu_support_aes() && AesSwitch) || (AesSwitch && force)) {
+			aesni = true;
 		}
-#endif // defined(__x86_64__) || defined(__i386__)
 
 		LogPrint(eLogInfo, "AESNI ", (aesni ? "enabled" : "disabled"));
-		LogPrint(eLogInfo, "AVX ", (avx ? "enabled" : "disabled"));
 	}
 }
 }

libi2pd/CPU.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2023, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -14,9 +14,8 @@ namespace i2p
 namespace cpu
 {
 	extern bool aesni;
-	extern bool avx;
 
-	void Detect(bool AesSwitch, bool AvxSwitch, bool force);
+	void Detect(bool AesSwitch, bool force);
 }
 }
 

libi2pd/Config.cpp

@@ -193,7 +193,7 @@ namespace config {
 		options_description precomputation("Precomputation options");
 		precomputation.add_options()
 			("precomputation.elgamal",
-#if defined(__x86_64__)
+#if (defined(_M_AMD64) || defined(__x86_64__))
 				value<bool>()->default_value(false),
 #else
 				value<bool>()->default_value(true),
@@ -308,7 +308,7 @@ namespace config {
 		options_description cpuext("CPU encryption extensions options");
 		cpuext.add_options()
 			("cpuext.aesni", bool_switch()->default_value(true),                     "Use auto detection for AESNI CPU extensions. If false, AESNI will be not used")
-			("cpuext.avx", bool_switch()->default_value(true),                       "Use auto detection for AVX CPU extensions. If false, AVX will be not used")
+			("cpuext.avx", bool_switch()->default_value(false),                      "Deprecated option")
 			("cpuext.force", bool_switch()->default_value(false),                    "Force usage of CPU extensions. Useful when cpuinfo is not available on virtual machines")
 		;
 

libi2pd/Crypto.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2022, The PurpleI2P Project
+* Copyright (c) 2013-2023, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -28,6 +28,12 @@
 #include "I2PEndian.h"
 #include "Log.h"
 
+#if defined(__AES__) && !defined(_MSC_VER) && ((defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_IX86) || defined(__i386__)))
+	#define SUPPORTS_AES 1
+#else
+	#define SUPPORTS_AES 0
+#endif
+
 namespace i2p
 {
 namespace crypto
@@ -361,7 +367,7 @@ namespace crypto
 		BIGNUM * b1 = BN_CTX_get (ctx);
 		BIGNUM * b = BN_CTX_get (ctx);
 		// select random k
-#if defined(__x86_64__)
+#if (defined(_M_AMD64) || defined(__x86_64__))
 		BN_rand (k, ELGAMAL_FULL_EXPONENT_NUM_BITS, -1, 1); // full exponent for x64
 #else
 		BN_rand (k, ELGAMAL_SHORT_EXPONENT_NUM_BITS, -1, 1); // short exponent of 226 bits
@@ -428,7 +434,7 @@ namespace crypto
 
 	void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub)
 	{
-#if defined(__x86_64__) || defined(__i386__) || defined(_MSC_VER)
+#if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_IX86) || defined(__i386__)) || defined(_MSC_VER)
 		RAND_bytes (priv, 256);
 #else
 		// lower 226 bits (28 bytes and 2 bits) only. short exponent
@@ -555,7 +561,7 @@ namespace crypto
 	}
 
 // AES
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 	#define KeyExpansion256(round0,round1) \
 		"pshufd $0xff, %%xmm2, %%xmm2 \n" \
 		"movaps %%xmm1, %%xmm4 \n" \
@@ -580,7 +586,7 @@ namespace crypto
 		"movaps %%xmm3, "#round1"(%[sched]) \n"
 #endif
 
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 	void ECBCryptoAESNI::ExpandKey (const AESKey& key)
 	{
 		__asm__
@@ -621,7 +627,7 @@ namespace crypto
 #endif
 
 
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 	#define EncryptAES256(sched) \
 		"pxor (%["#sched"]), %%xmm0 \n" \
 		"aesenc	16(%["#sched"]), %%xmm0 \n" \
@@ -642,7 +648,7 @@ namespace crypto
 
 	void ECBEncryption::Encrypt (const ChipherBlock * in, ChipherBlock * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -650,7 +656,9 @@ namespace crypto
 				"movups (%[in]), %%xmm0 \n"
 				EncryptAES256(sched)
 				"movups %%xmm0, (%[out]) \n"
-					: : [sched]"r"(GetKeySchedule ()), [in]"r"(in), [out]"r"(out) : "%xmm0", "memory"
+				:
+				: [sched]"r"(GetKeySchedule ()), [in]"r"(in), [out]"r"(out)
+				: "%xmm0", "memory"
 			);
 		}
 		else
@@ -660,7 +668,7 @@ namespace crypto
 		}
 	}
 
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 	#define DecryptAES256(sched) \
 		"pxor 224(%["#sched"]), %%xmm0 \n" \
 		"aesdec	208(%["#sched"]), %%xmm0 \n" \
@@ -681,7 +689,7 @@ namespace crypto
 
 	void ECBDecryption::Decrypt (const ChipherBlock * in, ChipherBlock * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -689,7 +697,9 @@ namespace crypto
 				"movups (%[in]), %%xmm0 \n"
 				DecryptAES256(sched)
 				"movups %%xmm0, (%[out]) \n"
-					: : [sched]"r"(GetKeySchedule ()), [in]"r"(in), [out]"r"(out) : "%xmm0", "memory"
+				:
+				: [sched]"r"(GetKeySchedule ()), [in]"r"(in), [out]"r"(out)
+				: "%xmm0", "memory"
 			);
 		}
 		else
@@ -699,7 +709,7 @@ namespace crypto
 		}
 	}
 
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 	#define CallAESIMC(offset) \
 		"movaps "#offset"(%[shed]), %%xmm0 \n" \
 		"aesimc %%xmm0, %%xmm0 \n" \
@@ -708,7 +718,7 @@ namespace crypto
 
 	void ECBEncryption::SetKey (const AESKey& key)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			ExpandKey (key);
@@ -722,7 +732,7 @@ namespace crypto
 
 	void ECBDecryption::SetKey (const AESKey& key)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			ExpandKey (key); // expand encryption key first
@@ -742,7 +752,9 @@ namespace crypto
 				CallAESIMC(176)
 				CallAESIMC(192)
 				CallAESIMC(208)
-					: : [shed]"r"(GetKeySchedule ()) : "%xmm0", "memory"
+				:
+				: [shed]"r"(GetKeySchedule ())
+				: "%xmm0", "memory"
 			);
 		}
 		else
@@ -754,7 +766,7 @@ namespace crypto
 
 	void CBCEncryption::Encrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -799,7 +811,7 @@ namespace crypto
 
 	void CBCEncryption::Encrypt (const uint8_t * in, uint8_t * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -823,7 +835,7 @@ namespace crypto
 
 	void CBCDecryption::Decrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -869,7 +881,7 @@ namespace crypto
 
 	void CBCDecryption::Decrypt (const uint8_t * in, uint8_t * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -893,7 +905,7 @@ namespace crypto
 
 	void TunnelEncryption::Encrypt (const uint8_t * in, uint8_t * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -934,7 +946,7 @@ namespace crypto
 
 	void TunnelDecryption::Decrypt (const uint8_t * in, uint8_t * out)
 	{
-#if defined(__AES__) && (defined(__x86_64__) || defined(__i386__))
+#if SUPPORTS_AES
 		if(i2p::cpu::aesni)
 		{
 			__asm__
@@ -1285,9 +1297,9 @@ namespace crypto
 		}
 	}*/
 
-	void InitCrypto (bool precomputation, bool aesni, bool avx, bool force)
+	void InitCrypto (bool precomputation, bool aesni, bool force)
 	{
-		i2p::cpu::Detect (aesni, avx, force);
+		i2p::cpu::Detect (aesni, force);
 #if LEGACY_OPENSSL
 		SSL_library_init ();
 #endif
@@ -1297,7 +1309,7 @@ namespace crypto
 		CRYPTO_set_locking_callback (OpensslLockingCallback);*/
 		if (precomputation)
 		{
-#if defined(__x86_64__)
+#if (defined(_M_AMD64) || defined(__x86_64__))
 			g_ElggTable = new BIGNUM * [ELGAMAL_FULL_EXPONENT_NUM_BYTES][255];
 			PrecalculateElggTable (g_ElggTable, ELGAMAL_FULL_EXPONENT_NUM_BYTES);
 #else
@@ -1312,7 +1324,7 @@ namespace crypto
 		if (g_ElggTable)
 		{
 			DestroyElggTable (g_ElggTable,
-#if defined(__x86_64__)
+#if (defined(_M_AMD64) || defined(__x86_64__))
 				ELGAMAL_FULL_EXPONENT_NUM_BYTES
 #else
 				ELGAMAL_SHORT_EXPONENT_NUM_BYTES

libi2pd/Crypto.h

@@ -307,7 +307,7 @@ namespace crypto
 	void InitNoiseIKState (NoiseSymmetricState& state, const uint8_t * pub); // Noise_IK (ratchets)
 
 // init and terminate
-	void InitCrypto (bool precomputation, bool aesni, bool avx, bool force);
+	void InitCrypto (bool precomputation, bool aesni, bool force);
 	void TerminateCrypto ();
 }
 }

libi2pd/Identity.cpp

@@ -803,29 +803,12 @@ namespace data
 	XORMetric operator^(const IdentHash& key1, const IdentHash& key2)
 	{
 		XORMetric m;
-#if (defined(__x86_64__) || defined(__i386__)) && defined(__AVX__) // not all X86 targets supports AVX (like old Pentium, see #1600)
-		if(i2p::cpu::avx)
-		{
-			__asm__
-			(
-				"vmovups %1, %%ymm0 \n"
-				"vmovups %2, %%ymm1 \n"
-				"vxorps %%ymm0, %%ymm1, %%ymm1 \n"
-				"vmovups %%ymm1, %0 \n"
-				: "=m"(*m.metric)
-				: "m"(*key1), "m"(*key2)
-				: "memory", "%xmm0", "%xmm1" // should be replaced by %ymm0/1 once supported by compiler
-			);
-		}
-		else
-#endif
-		{
+
 		const uint64_t * hash1 = key1.GetLL (), * hash2 = key2.GetLL ();
 		m.metric_ll[0] = hash1[0] ^ hash2[0];
 		m.metric_ll[1] = hash1[1] ^ hash2[1];
 		m.metric_ll[2] = hash1[2] ^ hash2[2];
 		m.metric_ll[3] = hash1[3] ^ hash2[3];
-		}
 
 		return m;
 	}

libi2pd/api.cpp

@@ -38,9 +38,8 @@ namespace api
 
 		bool precomputation; i2p::config::GetOption("precomputation.elgamal", precomputation);
 		bool aesni; i2p::config::GetOption("cpuext.aesni", aesni);
-		bool avx; i2p::config::GetOption("cpuext.avx", avx);
 		bool forceCpuExt; i2p::config::GetOption("cpuext.force", forceCpuExt);
-		i2p::crypto::InitCrypto (precomputation, aesni, avx, forceCpuExt);
+		i2p::crypto::InitCrypto (precomputation, aesni, forceCpuExt);
 
 		int netID; i2p::config::GetOption("netid", netID);
 		i2p::context.SetNetID (netID);