1 files changed, 108 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/utils/bswap.h b/comm/third_party/botan/src/lib/utils/bswap.h
new file mode 100644
index 0000000000..584fa33234
--- /dev/null
+++ b/comm/third_party/botan/src/lib/utils/bswap.h
@@ -0,0 +1,108 @@
+/*
+* Byte Swapping Operations
+* (C) 1999-2011,2018 Jack Lloyd
+* (C) 2007 Yves Jerschow
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_BYTE_SWAP_H_
+#define BOTAN_BYTE_SWAP_H_
+
+#include <botan/types.h>
+
+#if defined(BOTAN_BUILD_COMPILER_IS_MSVC)
+  #include <stdlib.h>
+#endif
+
+BOTAN_FUTURE_INTERNAL_HEADER(bswap.h)
+
+namespace Botan {
+
+/**
+* Swap a 16 bit integer
+*/
+inline uint16_t reverse_bytes(uint16_t val)
+   {
+#if defined(BOTAN_BUILD_COMPILER_IS_GCC) || defined(BOTAN_BUILD_COMPILER_IS_CLANG) || defined(BOTAN_BUILD_COMPILER_IS_XLC)
+   return __builtin_bswap16(val);
+#else
+   return static_cast<uint16_t>((val << 8) | (val >> 8));
+#endif
+   }
+
+/**
+* Swap a 32 bit integer
+*/
+inline uint32_t reverse_bytes(uint32_t val)
+   {
+#if defined(BOTAN_BUILD_COMPILER_IS_GCC) || defined(BOTAN_BUILD_COMPILER_IS_CLANG) || defined(BOTAN_BUILD_COMPILER_IS_XLC)
+   return __builtin_bswap32(val);
+
+#elif defined(BOTAN_BUILD_COMPILER_IS_MSVC)
+   return _byteswap_ulong(val);
+
+#elif defined(BOTAN_USE_GCC_INLINE_ASM) && defined(BOTAN_TARGET_CPU_IS_X86_FAMILY)
+
+   // GCC-style inline assembly for x86 or x86-64
+   asm("bswapl %0" : "=r" (val) : "0" (val));
+   return val;
+
+#else
+   // Generic implementation
+   uint16_t hi = static_cast<uint16_t>(val >> 16);
+   uint16_t lo = static_cast<uint16_t>(val);
+
+   hi = reverse_bytes(hi);
+   lo = reverse_bytes(lo);
+
+   return (static_cast<uint32_t>(lo) << 16) | hi;
+#endif
+   }
+
+/**
+* Swap a 64 bit integer
+*/
+inline uint64_t reverse_bytes(uint64_t val)
+   {
+#if defined(BOTAN_BUILD_COMPILER_IS_GCC) || defined(BOTAN_BUILD_COMPILER_IS_CLANG) || defined(BOTAN_BUILD_COMPILER_IS_XLC)
+   return __builtin_bswap64(val);
+
+#elif defined(BOTAN_BUILD_COMPILER_IS_MSVC)
+   return _byteswap_uint64(val);
+
+#elif defined(BOTAN_USE_GCC_INLINE_ASM) && defined(BOTAN_TARGET_ARCH_IS_X86_64)
+   // GCC-style inline assembly for x86-64
+   asm("bswapq %0" : "=r" (val) : "0" (val));
+   return val;
+
+#else
+   /* Generic implementation. Defined in terms of 32-bit bswap so any
+    * optimizations in that version can help.
+    */
+
+   uint32_t hi = static_cast<uint32_t>(val >> 32);
+   uint32_t lo = static_cast<uint32_t>(val);
+
+   hi = reverse_bytes(hi);
+   lo = reverse_bytes(lo);
+
+   return (static_cast<uint64_t>(lo) << 32) | hi;
+#endif
+   }
+
+/**
+* Swap 4 Ts in an array
+*/
+template<typename T>
+inline void bswap_4(T x[4])
+   {
+   x[0] = reverse_bytes(x[0]);
+   x[1] = reverse_bytes(x[1]);
+   x[2] = reverse_bytes(x[2]);
+   x[3] = reverse_bytes(x[3]);
+   }
+
+}
+
+#endif