Trying to migrate Chromium to the "link all the asm files together"
strategy broke the aarch64 Android build because some of the ifdef'd out
assembly files were missing the .note.gnu.property section for BTI. If
we add support for IBT, that'll be another one.
To fix this, introduce <openssl/asm_base.h>, which must be included at
the start of every assembly file (before the target ifdefs). This does a
couple things:
- It emits BTI and noexecstack markers into every assembly file, even
those that ifdef themselves out.
- It resolves the MSan -> OPENSSL_NO_ASM logic, so we only need to do it
once.
- It defines the same OPENSSL_X86_64, etc., defines we set elsewhere, so
we can ensure they're consistent.
This required carving files up a bit. <openssl/base.h> has a lot of
things, such that trying to guard everything in it on __ASSEMBLER__
would be tedious. Instead, I moved the target defines to a new
<openssl/target.h>. Then <openssl/asm_base.h> is the new header that
pulls in all those things.
Bug: 542
Change-Id: I1682b4d929adea72908655fa1bb15765a6b3473b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/60765
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
