aarch64: Enable building the aarch64 cipher assembly for windows
* cipher/asm-common-aarch64.h: New. * cipher/camellia-aarch64.S: Use ELF macro, use x19 instead of x18. * cipher/chacha20-aarch64.S: Use ELF macro, don't use GOT on windows. * cipher/cipher-gcm-armv8-aarch64-ce.S: Use ELF macro. * cipher/rijndael-aarch64.S: Use ELF macro. * cipher/rijndael-armv8-aarch64-ce.S: Use ELF macro. * cipher/sha1-armv8-aarch64-ce.S: Use ELF macro. * cipher/sha256-armv8-aarch64-ce.S: Use ELF macro. * cipher/twofish-aarch64.S: Use ELF macro. * configure.ac: Don't require .size and .type in aarch64 assembly check.
Don't require .type and .size in configure; we can make
them optional via a preprocessor macro.
This is mostly a mechanical change, wrapping the .type and .size
directives in an ELF() macro, with two actual manual changes:
(when targeting windows):
- Don't load global symbols via a GOT (in chacha20)
- Don't use the x18 register (in camellia); back up and restore x19 in the prologue/epilogue and use that instead.
x18 is a platform specific register; on linux, it's free to be used
by user code, while it's reserved for platform use on windows and
darwin. Always use x19 instead of x18 for consistency.
- Signed-off-by: Martin Storsjö <email@example.com>