1609181 - Detect ARM (32-bit) CPU features on FreeBSD

Status: RESOLVED FIXED

(NSS :: Libraries, enhancement, P3)

Description

[Jan Beich]

FreeBSD 12.0 has a function similar to getauxval, see https://github.com/freebsd/freebsd/commit/990c7fb0441b. elf_aux_info uses KERN_PROC_AUXV under the hood but AT_HWCAP isn't available before FreeBSD 11.2.

Comment 1

[Jan Beich]

Attachment: Use getauxval paths if not protected by #ifdef __linux__ (non-aarch64)

Implement getauxval via elf_aux_info to avoid code duplication.
AT_HWCAP* can be used on powerpc* and riscv64 as well.

https://treeherder.mozilla.org/#/jobs?repo=nss-try&revision=8dd1916016d9ff25914e32d6ba7b8cee677c5ff1

Comment 2

[Jan Beich]

Attachment: Use getauxval paths if not protected by #ifdef __linux__ (non-aarch64), v1.1

Oops, explicitly exclude on FreeBSD aarch64 after bug 1575843.

blinit.c:118:22: error: unused function 'freebl_getauxval' [-Werror,-Wunused-function]
static unsigned long getauxval(unsigned long type)
                     ^
blinit.c:117:19: note: expanded from macro 'getauxval'
#define getauxval freebl_getauxval
                  ^
1 error generated.

Comment 3

[Jan Beich]

Attachment: Use getauxval paths if not protected by #ifdef __linux__ (non-aarch64), v1.2

Oops, bad style but clang-format doesn't warn:

• When tabs are used instead of spaces
• When if doesn't end with {

Comment 4

[Jan Beich]

Comment on attachment 9120823 [details] [diff] [review]
Use getauxval paths if not protected by #ifdef __linux__ (non-aarch64), v1.2

Pushed this version downstream to get more exposure:
https://github.com/freebsd/freebsd-ports/commit/72da66e8ccdc114da1df6939bff67ecb84381bda

Comment 5

[J.C. Jones [:jcj] (he/they)]

Comment on attachment 9120823 [details] [diff] [review]
Use getauxval paths if not protected by #ifdef __linux__ (non-aarch64), v1.2

Review of attachment 9120823 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good here, thanks!

Comment 6

[J.C. Jones [:jcj] (he/they)]

https://hg.mozilla.org/projects/nss/rev/edb60bae921934f4a9421d8bfca28301e7e91dc2