diff options
author | David Benjamin <davidben@chromium.org> | 2015-03-09 21:51:51 +0300 |
---|---|---|
committer | Adam Langley <agl@google.com> | 2015-03-10 05:32:05 +0300 |
commit | 389939422a2966731809c8c75a79da7db4d29b10 (patch) | |
tree | c89acd99d3bc257cf14ce578f863c959a1083785 /crypto/sha | |
parent | 5a93342fabc7c82bb9900ba3ba7cf0b976054027 (diff) |
ARMv4 assembly pack: add Cortex-A15 performance data.
(Imported from upstream's e390ae50e0bc41676994c6fa23f7b65a8afc4d7f)
Change-Id: Ifee85b0936c06c42cc7c09f8327d15fec51da48a
Reviewed-on: https://boringssl-review.googlesource.com/3832
Reviewed-by: Adam Langley <agl@google.com>
Diffstat (limited to 'crypto/sha')
-rw-r--r-- | crypto/sha/asm/sha1-armv4-large.pl | 4 | ||||
-rw-r--r-- | crypto/sha/asm/sha512-armv4.pl | 13 |
2 files changed, 6 insertions, 11 deletions
diff --git a/crypto/sha/asm/sha1-armv4-large.pl b/crypto/sha/asm/sha1-armv4-large.pl index 1ffa041e..d8f30ae7 100644 --- a/crypto/sha/asm/sha1-armv4-large.pl +++ b/crypto/sha/asm/sha1-armv4-large.pl @@ -60,7 +60,9 @@ # is ~2.5x larger and there are some redundant instructions executed # when processing last block, improvement is not as big for smallest # blocks, only ~30%. Snapdragon S4 is a tad faster, 6.4 cycles per -# byte, which is also >80% faster than integer-only code. +# byte, which is also >80% faster than integer-only code. Cortex-A15 +# is even faster spending 5.6 cycles per byte outperforming integer- +# only code by factor of 2. # May 2014. # diff --git a/crypto/sha/asm/sha512-armv4.pl b/crypto/sha/asm/sha512-armv4.pl index bfe28c45..4a12b493 100644 --- a/crypto/sha/asm/sha512-armv4.pl +++ b/crypto/sha/asm/sha512-armv4.pl @@ -34,16 +34,9 @@ # terms it's 22.6 cycles per byte, which is disappointing result. # Technical writers asserted that 3-way S4 pipeline can sustain # multiple NEON instructions per cycle, but dual NEON issue could -# not be observed, and for NEON-only sequences IPC(*) was found to -# be limited by 1:-( 0.33 and 0.66 were measured for sequences with -# ILPs(*) of 1 and 2 respectively. This in turn means that you can -# even find yourself striving, as I did here, for achieving IPC -# adequate to one delivered by Cortex A8 [for reference, it's -# 0.5 for ILP of 1, and 1 for higher ILPs]. -# -# (*) ILP, instruction-level parallelism, how many instructions -# *can* execute at the same time. IPC, instructions per cycle, -# indicates how many instructions actually execute. +# not be observed, see http://www.openssl.org/~appro/Snapdragon-S4.html +# for further details. On side note Cortex-A15 processes one byte in +# 16 cycles. # Byte order [in]dependence. ========================================= # |