Add AVX2-enabled functions for x86-64

README

@@ -42,15 +42,15 @@ Architecture-specific notes:
 		To use NEON instructions, add "-mfpu=neon" to CFLAGS.
 	x86:	The miner checks for SSE2 instructions support at runtime,
 		and uses them if they are available.
-	x86-64:	The miner can take advantage of AVX and XOP instructions,
+	x86-64:	The miner can take advantage of AVX, AVX2 and XOP instructions,
 		but only if both the CPU and the operating system support them.
 		    * Linux supports AVX starting from kernel version 2.6.30.
 		    * FreeBSD supports AVX starting with 9.1-RELEASE.
 		    * Mac OS X added AVX support in the 10.6.8 update.
 		    * Windows supports AVX starting from Windows 7 SP1 and
 		      Windows Server 2008 R2 SP1.
 		The configure script outputs a warning if the assembler
-		cannot compile AVX or XOP instructions. In that case, the miner
+		doesn't support some instruction sets. In that case, the miner
 		can still be built, but unavailable optimizations are left off.
 
 Usage instructions:  Run "minerd --help" to see options.

configure.ac

@@ -77,6 +77,14 @@ then
       AC_MSG_RESULT(no)
       AC_MSG_WARN([The assembler does not support the XOP instruction set.])
     )
+    AC_MSG_CHECKING(whether we can compile AVX2 code)
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,[asm ("vpaddd %ymm0, %ymm1, %ymm2");])],
+      AC_DEFINE(USE_AVX2, 1, [Define to 1 if AVX2 assembly is available.])
+      AC_MSG_RESULT(yes)
+    ,
+      AC_MSG_RESULT(no)
+      AC_MSG_WARN([The assembler does not support the AVX2 instruction set.])
+    )
   ,
     AC_MSG_RESULT(no)
     AC_MSG_WARN([The assembler does not support the AVX instruction set.])

cpu-miner.c

@@ -668,7 +668,7 @@ static void *miner_thread(void *userdata)
 	int thr_id = mythr->id;
 	struct work work;
 	uint32_t max_nonce;
-	uint32_t end_nonce = 0xffffffffU / opt_n_threads * (thr_id + 1) - 0x10;
+	uint32_t end_nonce = 0xffffffffU / opt_n_threads * (thr_id + 1) - 0x20;
 	unsigned char *scratchbuf = NULL;
 	char s[16];
 	int i;

miner.h

@@ -141,6 +141,13 @@ void sha256_init_4way(uint32_t *state);
 void sha256_transform_4way(uint32_t *state, const uint32_t *block, int swap);
 #endif
 
+#if defined(__x86_64__) && defined(USE_AVX2)
+#define HAVE_SHA256_8WAY 1
+int sha256_use_8way();
+void sha256_init_8way(uint32_t *state);
+void sha256_transform_8way(uint32_t *state, const uint32_t *block, int swap);
+#endif
+
 extern int scanhash_sha256d(int thr_id, uint32_t *pdata,
 	const uint32_t *ptarget, uint32_t max_nonce, unsigned long *hashes_done);