This is much less interesting (stack-based parameters, Windows and SysV
match, no SEH concerns as far as I can tell) than x86_64, but it was
easy to do and I'm more familiar with x86 than ARM, so it made a better
second architecture to make sure all the architecture ifdefs worked out.
Also fix a bug in the x86_64 direction flag code. It was shifting in the
wrong direction, making give 0 or 1<<20 rather than 0 or 1.
(Happily, x86_64 appears to be unique in having vastly different calling
conventions between OSs. x86 is the same between SysV and Windows, and
ARM had the good sense to specify a (mostly) common set of rules.)
Since a lot of the assembly functions use the same names and the tests
were written generically, merely dropping in a trampoline and
CallerState implementation gives us a bunch of ABI tests for free.
Change-Id: I15408c18d43e88cfa1c5c0634a8b268a150ed961
Reviewed-on: https://boringssl-review.googlesource.com/c/34624
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
e569c7e25d