Fix bug affecting AltiVec on ppc64le processors

2 files changed, 5 insertions, 8 deletions

diff --git a/news.rst b/news.rst
index 3624280e5..c3304302b 100644
--- a/news.rst
+++ b/news.rst
@@ -35,6 +35,9 @@ Version 2.3.0, Not Yet Released
 * Workaround a GCC 7 bug that caused miscompilation of the GOST-34.11 hash
   function on x86-32. (GH #882 #1148)
 
+* Fix a bug in SIMD_4x32 which affected little-endian PowerPC processors.
+  This would cause test failures for Serpent, among other problems.
+
 * Fix Altivec runtime detection, which was broken starting in Botan 2.1.0
 
 * Silence a Clang warning in create_private_key (GH #1150)
diff --git a/src/lib/utils/simd/simd_32.h b/src/lib/utils/simd/simd_32.h
index def933f4a..6d9223a38 100644
--- a/src/lib/utils/simd/simd_32.h
+++ b/src/lib/utils/simd/simd_32.h
@@ -214,18 +214,12 @@ class SIMD_4x32 final
 
 #elif defined(BOTAN_SIMD_USE_ALTIVEC)
 
-         __vector unsigned char perm = vec_lvsl(0, static_cast<uint32_t*>(nullptr));
-         if(CPUID::is_big_endian())
-            {
-            perm = vec_xor(perm, vec_splat_u8(3)); // bswap vector
-            }
-
          union {
             __vector unsigned int V;
             uint32_t R[4];
             } vec;
-         vec.V = vec_perm(m_vmx, m_vmx, perm);
-         Botan::store_be(out, vec.R[0], vec.R[1], vec.R[2], vec.R[3]);
+         vec.V = m_vmx;
+         Botan::store_le(out, vec.R[0], vec.R[1], vec.R[2], vec.R[3]);
 
 #elif defined(BOTAN_SIMD_USE_NEON)