boringssl/crypto/cpu-arm-asm.S
Adam Langley d062c8afba Probe for NEON support if getauxval is missing.
Android didn't have getauxval until Jelly Bean (4.1). This means that
BoringSSL running on older Androids won't be able to detect NEON
support. (This is moot for Chromium because Chromium calls
android_getCpuFeatures and sets the NEON flag itself, but other users of
BoringSSL on Android probably won't do that.)

This change mirrors a little of what upstream does and tries running a
NEON instruction with a handler for SIGILL installed.

Change-Id: I853b85c37ffb049b240582d71fcf07adedc37a30
Reviewed-on: https://boringssl-review.googlesource.com/3190
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2015-02-02 19:51:14 +00:00

33 lines
1.1 KiB
ArmAsm

# Copyright (c) 2014, Google Inc.
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
# OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#if !defined(OPENSSL_NO_ASM)
.syntax unified
.cpu cortex-a8
.fpu neon
.text
.thumb
.align 2
.global CRYPTO_arm_neon_probe
.hidden CRYPTO_arm_neon_probe
.type CRYPTO_arm_neon_probe, %function
.thumb_func
CRYPTO_arm_neon_probe:
vorr q1, q1, q1
bx lr
.section .note.GNU-stack,"",%progbits
#endif /* !OPENSSL_NO_ASM */