cmake: Build bitcoin_crypto library

cmake/introspection.cmake

@@ -158,3 +158,70 @@ check_cxx_source_compiles("
   }
   " HAVE_SYSCTL_ARND
 )
+
+if(NOT MSVC)
+  include(CheckSourceCompilesAndLinks)
+
+  # Check for SSE4.1 intrinsics.
+  set(SSE41_CXXFLAGS -msse4.1)
+  check_cxx_source_compiles_with_flags("${SSE41_CXXFLAGS}" "
+    #include <immintrin.h>
+
+    int main()
+    {
+      __m128i a = _mm_set1_epi32(0);
+      __m128i b = _mm_set1_epi32(1);
+      __m128i r = _mm_blend_epi16(a, b, 0xFF);
+      return _mm_extract_epi32(r, 3);
+    }
+    " HAVE_SSE41
+  )
+  set(ENABLE_SSE41 ${HAVE_SSE41})
+
+  # Check for AVX2 intrinsics.
+  set(AVX2_CXXFLAGS -mavx -mavx2)
+  check_cxx_source_compiles_with_flags("${AVX2_CXXFLAGS}" "
+    #include <immintrin.h>
+
+    int main()
+    {
+      __m256i l = _mm256_set1_epi32(0);
+      return _mm256_extract_epi32(l, 7);
+    }
+    " HAVE_AVX2
+  )
+  set(ENABLE_AVX2 ${HAVE_AVX2})
+
+  # Check for x86 SHA-NI intrinsics.
+  set(X86_SHANI_CXXFLAGS -msse4 -msha)
+  check_cxx_source_compiles_with_flags("${X86_SHANI_CXXFLAGS}" "
+    #include <immintrin.h>
+
+    int main()
+    {
+      __m128i i = _mm_set1_epi32(0);
+      __m128i j = _mm_set1_epi32(1);
+      __m128i k = _mm_set1_epi32(2);
+      return _mm_extract_epi32(_mm_sha256rnds2_epu32(i, j, k), 0);
+    }
+    " HAVE_X86_SHANI
+  )
+  set(ENABLE_X86_SHANI ${HAVE_X86_SHANI})
+
+  # Check for ARMv8 SHA-NI intrinsics.
+  set(ARM_SHANI_CXXFLAGS -march=armv8-a+crypto)
+  check_cxx_source_compiles_with_flags("${ARM_SHANI_CXXFLAGS}" "
+    #include <arm_neon.h>
+
+    int main()
+    {
+      uint32x4_t a, b, c;
+      vsha256h2q_u32(a, b, c);
+      vsha256hq_u32(a, b, c);
+      vsha256su0q_u32(a, b);
+      vsha256su1q_u32(a, b, c);
+    }
+    " HAVE_ARM_SHANI
+  )
+  set(ENABLE_ARM_SHANI ${HAVE_ARM_SHANI})
+endif()