From bac252a5e39d793be90215213e9c6e7b56fe0e6b Mon Sep 17 00:00:00 2001 From: Andy Polyakov Date: Thu, 20 Jan 2005 10:33:37 +0000 Subject: Bug-fix in CBC encrypt tail processing and commentary section update. --- crypto/aes/asm/aes-586.pl | 45 +++++++++++++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 16 deletions(-) (limited to 'crypto') diff --git a/crypto/aes/asm/aes-586.pl b/crypto/aes/asm/aes-586.pl index 4263a7e1dc..ee02ded463 100755 --- a/crypto/aes/asm/aes-586.pl +++ b/crypto/aes/asm/aes-586.pl @@ -6,7 +6,7 @@ # forms are granted according to the OpenSSL license. # ==================================================================== # -# Version 3.0. +# Version 3.1. # # You might fail to appreciate this module performance from the first # try. If compared to "vanilla" linux-ia32-icc target, i.e. considered @@ -46,23 +46,27 @@ # Instruction Level Parallelism, and it indeed resulted in up to 15% # better performance on most recent µ-archs... # -# Current ECB performance numbers for 128-bit key in cycles per byte -# [measure commonly used by AES benchmarkers] are: +# Current ECB performance numbers for 128-bit key in CPU cycles per +# processed byte [measure commonly used by AES benchmarkers] are: # # small footprint fully unrolled # P4[-3] 23[24] 22[23] # AMD K8 19 18 -# PIII 26(*) 23 +# PIII 26 23 # Pentium 63(*) 52 # # (*) Performance difference between small footprint code and fully -# unrolled in more commonly used CBC mode is not as big, 7% for -# PIII and 15% for Pentium, which I consider tolerable. +# unrolled in more commonly used CBC mode is not as big, 4% for +# for Pentium. PIII's ~13% difference [in both cases in 3rd +# version] is considered tolerable... # # Third version adds AES_cbc_encrypt implementation, which resulted in -# up to 40% performance imrovement of CBC benchmark results [on most -# recent µ-archs]. CBC performance is virtually as good as ECB now and -# sometimes even better, because function prologues and epilogues are +# up to 40% performance imrovement of CBC benchmark results. 40% was +# observed on P4 core, where "overall" imrovement coefficient, i.e. if +# compared to PIC generated by GCC and in CBC mode, was observed to be +# as large as 4x:-) CBC performance is virtually identical to ECB now +# and on some platforms even better, e.g. 56 "small" cycles/byte on +# senior Pentium, because certain function prologues and epilogues are # effectively taken out of the loop... push(@INC,"perlasm","../../perlasm"); @@ -79,8 +83,9 @@ $acc="esi"; $small_footprint=1; # $small_footprint=1 code is ~5% slower [on # recent µ-archs], but ~5 times smaller! - # I favor compact code, because it minimizes - # cache contention... + # I favor compact code to minimize cache + # contention and in hope to "collect" 5% back + # in real-life applications... $vertical_spin=0; # shift "verticaly" defaults to 0, because of # its proof-of-concept status... @@ -1296,12 +1301,18 @@ sub declast() &push ($key eq "edi" ? $key : ""); # push ivp &pushf (); &mov ($key,&wparam(1)); # load out - &xor ($s0,$s0); - &mov (&DWP(0,$key),$s0); # zero output - &mov (&DWP(4,$key),$s0); - &mov (&DWP(8,$key),$s0); - &mov (&DWP(12,$key),$s0); + &mov ($s1,16); + &sub ($s1,$s2); + &cmp ($key,$acc); # compare with inp + &je (&label("enc_in_place")); &data_word(0x90A4F3FC); # cld; rep movsb; nop # copy input + &jmp (&label("enc_skip_in_place")); + &set_label("enc_in_place"); + &lea ($key,&DWP(0,$key,$s2)); + &set_label("enc_skip_in_place"); + &mov ($s2,$s1); + &xor ($s0,$s0); + &data_word(0x90AAF3FC); # cld; rep stosb; nop # zero tail &popf (); &pop ($key); # pop ivp @@ -1456,6 +1467,8 @@ sub declast() &pushf (); &data_word(0x90A4F3FC); # cld; rep movsb; nop # restore tail &popf (); + + &align (4); &set_label("dec_out"); &stack_pop(5); &function_end("AES_cbc_encrypt"); -- cgit v1.2.3