scrypt SSE2

[novacoin.git] / src / scrypt.cpp

diff --git a/src/scrypt.cpp b/src/scrypt.cpp
index 5779127..32eea96 100644 (file)
--- a/src/scrypt.cpp
+++ b/src/scrypt.cpp
@@ -6,16 +6,26 @@
 #include "util.h"
 #include "net.h"
 
-#define SCRYPT_BUFFER_SIZE (131072 + 63)
+#ifdef USE_SSE2
+#ifdef _MSC_VER
+// MSVC 64bit is unable to use inline asm
+#include <intrin.h>
+#else
+// GCC Linux or i686-w64-mingw32
+#include <cpuid.h>
+#endif
+#endif
 
 extern "C" void scrypt_core(uint32_t *X, uint32_t *V);
-
+#ifdef USE_SSE2
+extern  uint256 scrypt_blockhash__sse2(const uint8_t* input);
+#endif
 /* cpu and memory intensive function to transform a 80 byte buffer into a 32 byte output
    scratchpad size needs to be at least 63 + (128 * r * p) + (256 * r + 64) + (128 * r * N) bytes
    r = 1, p = 1, N = 1024
  */
 
-uint256 scrypt_blockhash(const uint8_t* input)
+uint256 scrypt_blockhash_generic(const uint8_t* input)
 {
     uint8_t scratchpad[SCRYPT_BUFFER_SIZE];
     uint32_t X[32];
@@ -29,3 +39,40 @@ uint256 scrypt_blockhash(const uint8_t* input)
 
     return result;
 }
+
+// By default, set to generic scrypt function. This will prevent crash in case when scrypt_detect_sse2() wasn't called
+uint256 (*scrypt_blockhash_detected)(const uint8_t* input) = &scrypt_blockhash_generic;
+
+#ifdef USE_SSE2
+void scrypt_detect_sse2()
+{
+    // 32bit x86 Linux or Windows, detect cpuid features
+    unsigned int cpuid_edx=0;
+#if defined(_MSC_VER)
+     // MSVC
+     int x86cpuid[4];
+     __cpuid(x86cpuid, 1);
+     cpuid_edx = (unsigned int)x86cpuid[3];
+#else // _MSC_VER
+    // Linux or i686-w64-mingw32 (gcc-4.6.3)
+    unsigned int eax, ebx, ecx;
+    __get_cpuid(1, &eax, &ebx, &ecx, &cpuid_edx);
+#endif // _MSC_VER
+
+    if (cpuid_edx & 1<<26)
+    {
+        scrypt_blockhash_detected = &scrypt_blockhash__sse2;
+        printf("scrypt: using scrypt-sse2 as detected.\n");
+    }
+    else
+    {
+        scrypt_blockhash_detected = &scrypt_blockhash_generic;
+        printf("scrypt: using scrypt-generic, SSE2 unavailable.\n");
+    }
+}
+#endif
+
+uint256 scrypt_blockhash(const uint8_t* input)
+{
+    return scrypt_blockhash_detected(input);
+}
\ No newline at end of file