By default the member, named m_mark, is set to the maximum number of elements. If SetMark() is called, then m_mark is adjusted. Upon deallocation and zeroization, STDMIN(m_size, m_mark) elements are zeroized.
We wanted to use a high water mark, but we could not track the writes to the allocation. operator[] would have been OK, but ::memcpy would have been problematic
These function are intended to catch mining and matching of library versions. BuildVersion provides CRYPTOPP_VERSION when the shared object was built. RuntimeVersion provides CRYPTOPP_VERSION the app compiled against, which could be different than the shared object's version
MOVBE is a modest gain over BSWAP. Though its guarded by CRYPTOPP_MOVBE_AVAILABLE, we cannot detect availability with a preprocessor macro. That is, GCC does not provide __MOVBE__ or similar. It has to be enabled manually
Since we switched to CRYPTOPP_ASSERT we don't have to worry about an accidental assert in production. We can now assert ValidateElement and ValidateGroup and let the code warn of potential problems during development.
This came about because ECGDSA inadvertently used GetGroupOrder() rather than GetSubgroupOrder(). The assert alerted to the problem area without the need for debugging
The macros that invoke GCC inline ASM have better code generation and speedup GCM ops by about 70 MiB/s on an Opteron 1100. The intrinsics are still available for Windows platforms and Visual Studio 2017 and above
It appears Apple Clang disgorges carryless multiply (PMULL) from Crypto (AES and SHA). The breakout added CRYPTOPP_BOOL_ARM_PMULL_INTRINSICS_AVAILABLE for PMULL, and retained CRYPTOPP_BOOL_ARM_CRYPTO_INTRINSICS_AVAILABLE for AES and SHA only
Targets with only object inputs do not work correctly with some
generators (like Xcode, see issue #355). Defining these directly in
terms of the source code files (rather than a reused set of object
files) allows correct builds in such cases. This can now be controlled
through a new option USE_INTERMEDIATE_OBJECTS_TARGET which defaults to
ON.
Jeffrey Walton
Marcel Raad
Heinrich Janzing