Re: 4 hashes parallel on SSE2 CPUs for 0.3.6
Re: 4 hashes parallel on SSE2 CPUs for 0.3.6
Date: August 14, 2010
Source: BitcoinTalk Forum
URL: https://satoshi.nakamotoinstitute.org/posts/bitcointalk/361/
MinGW GCC 4.5.0:
Crypto++ doesn't work, X86_SHA256_HashBlocks() never returns
I only got 4-way working with test.cpp but not when called by BitcoinMiner
MinGW GCC 4.4.1:
Crypto++ works
4-way SIGSEGV
GCC is definitely not aligning __m128i.
Even if we align our own __m128i variables, the compiler may decide to use a __m128i behind the scenes as a temporary variable.
By making our __m128i variables aligned and changing these inlines to defines, I was able to get it to work on 4.4.1 with -O0 only:
define Ch(b, c, d) ((b & c) ^ (~b & d))
define Maj(b, c, d) ((b & c) ^ (b & d) ^ (c & d))
define ROTR(x, n) (_mm_srli_epi32(x, n) | _mm_slli_epi32(x, 32 - n))
define SHR(x, n) _mm_srli_epi32(x, n)
But that's with -O0.