# below and combine it with reduction algorithm from x86 module.
# Performance improvement over previous version varies from 65% on
# Snapdragon S4 to 110% on Cortex A9. In absolute terms Cortex A8
-# processes one byte in 8.45 cycles, A9 - in 10.2, Snapdragon S4 -
-# in 9.33.
+# processes one byte in 8.45 cycles, A9 - in 10.2, A15 - in 7.63,
+# Snapdragon S4 - in 9.33.
#
# Câmara, D.; Gouvêa, C. P. L.; López, J. & Dahab, R.: Fast Software
# Polynomial Multiplication on ARM Processors using the NEON Engine.
# 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.
#
# 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. =========================================
#