xref: /openssl/crypto/bn/asm/via-mont.pl (revision 33388b44) 
1#! /usr/bin/env perl
2# Copyright 2006-2020 The OpenSSL Project Authors. All Rights Reserved.
3#
4# Licensed under the Apache License 2.0 (the "License").  You may not use
5# this file except in compliance with the License.  You can obtain a copy
6# in the file LICENSE in the source distribution or at
7# https://www.openssl.org/source/license.html
8
9#
10# ====================================================================
11# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
12# project. The module is, however, dual licensed under OpenSSL and
13# CRYPTOGAMS licenses depending on where you obtain it. For further
14# details see http://www.openssl.org/~appro/cryptogams/.
15# ====================================================================
16#
17# Wrapper around 'rep montmul', VIA-specific instruction accessing
18# PadLock Montgomery Multiplier. The wrapper is designed as drop-in
19# replacement for OpenSSL bn_mul_mont [first implemented in 0.9.9].
20#
21# Below are interleaved outputs from 'openssl speed rsa dsa' for 4
22# different software configurations on 1.5GHz VIA Esther processor.
23# Lines marked with "software integer" denote performance of hand-
24# coded integer-only assembler found in OpenSSL 0.9.7. "Software SSE2"
25# refers to hand-coded SSE2 Montgomery multiplication procedure found
26# OpenSSL 0.9.9. "Hardware VIA SDK" refers to padlock_pmm routine from
27# Padlock SDK 2.0.1 available for download from VIA, which naturally
28# utilizes the magic 'repz montmul' instruction. And finally "hardware
29# this" refers to *this* implementation which also uses 'repz montmul'
30#
31#                   sign    verify    sign/s verify/s
32# rsa  512 bits 0.001720s 0.000140s    581.4   7149.7	software integer
33# rsa  512 bits 0.000690s 0.000086s   1450.3  11606.0	software SSE2
34# rsa  512 bits 0.006136s 0.000201s    163.0   4974.5	hardware VIA SDK
35# rsa  512 bits 0.000712s 0.000050s   1404.9  19858.5	hardware this
36#
37# rsa 1024 bits 0.008518s 0.000413s    117.4   2420.8	software integer
38# rsa 1024 bits 0.004275s 0.000277s    233.9   3609.7	software SSE2
39# rsa 1024 bits 0.012136s 0.000260s     82.4   3844.5	hardware VIA SDK
40# rsa 1024 bits 0.002522s 0.000116s    396.5   8650.9	hardware this
41#
42# rsa 2048 bits 0.050101s 0.001371s     20.0    729.6	software integer
43# rsa 2048 bits 0.030273s 0.001008s     33.0    991.9	software SSE2
44# rsa 2048 bits 0.030833s 0.000976s     32.4   1025.1	hardware VIA SDK
45# rsa 2048 bits 0.011879s 0.000342s     84.2   2921.7	hardware this
46#
47# rsa 4096 bits 0.327097s 0.004859s      3.1    205.8	software integer
48# rsa 4096 bits 0.229318s 0.003859s      4.4    259.2	software SSE2
49# rsa 4096 bits 0.233953s 0.003274s      4.3    305.4	hardware VIA SDK
50# rsa 4096 bits 0.070493s 0.001166s     14.2    857.6	hardware this
51#
52# dsa  512 bits 0.001342s 0.001651s    745.2    605.7	software integer
53# dsa  512 bits 0.000844s 0.000987s   1185.3   1013.1	software SSE2
54# dsa  512 bits 0.001902s 0.002247s    525.6    444.9	hardware VIA SDK
55# dsa  512 bits 0.000458s 0.000524s   2182.2   1909.1	hardware this
56#
57# dsa 1024 bits 0.003964s 0.004926s    252.3    203.0	software integer
58# dsa 1024 bits 0.002686s 0.003166s    372.3    315.8	software SSE2
59# dsa 1024 bits 0.002397s 0.002823s    417.1    354.3	hardware VIA SDK
60# dsa 1024 bits 0.000978s 0.001170s   1022.2    855.0	hardware this
61#
62# dsa 2048 bits 0.013280s 0.016518s     75.3     60.5	software integer
63# dsa 2048 bits 0.009911s 0.011522s    100.9     86.8	software SSE2
64# dsa 2048 bits 0.009542s 0.011763s    104.8     85.0	hardware VIA SDK
65# dsa 2048 bits 0.002884s 0.003352s    346.8    298.3	hardware this
66#
67# To give you some other reference point here is output for 2.4GHz P4
68# running hand-coded SSE2 bn_mul_mont found in 0.9.9, i.e. "software
69# SSE2" in above terms.
70#
71# rsa  512 bits 0.000407s 0.000047s   2454.2  21137.0
72# rsa 1024 bits 0.002426s 0.000141s    412.1   7100.0
73# rsa 2048 bits 0.015046s 0.000491s     66.5   2034.9
74# rsa 4096 bits 0.109770s 0.002379s      9.1    420.3
75# dsa  512 bits 0.000438s 0.000525s   2281.1   1904.1
76# dsa 1024 bits 0.001346s 0.001595s    742.7    627.0
77# dsa 2048 bits 0.004745s 0.005582s    210.7    179.1
78#
79# Conclusions:
80# - VIA SDK leaves a *lot* of room for improvement (which this
81#   implementation successfully fills:-);
82# - 'rep montmul' gives up to >3x performance improvement depending on
83#   key length;
84# - in terms of absolute performance it delivers approximately as much
85#   as modern out-of-order 32-bit cores [again, for longer keys].
86
87$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
88push(@INC,"${dir}","${dir}../../perlasm");
89require "x86asm.pl";
90
91$output = pop and open STDOUT,">$output";
92
93&asm_init($ARGV[0]);
94
95# int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0, int num);
96$func="bn_mul_mont_padlock";
97
98$pad=16*1;	# amount of reserved bytes on top of every vector
99
100# stack layout
101$mZeroPrime=&DWP(0,"esp");		# these are specified by VIA
102$A=&DWP(4,"esp");
103$B=&DWP(8,"esp");
104$T=&DWP(12,"esp");
105$M=&DWP(16,"esp");
106$scratch=&DWP(20,"esp");
107$rp=&DWP(24,"esp");			# these are mine
108$sp=&DWP(28,"esp");
109# &DWP(32,"esp")			# 32 byte scratch area
110# &DWP(64+(4*$num+$pad)*0,"esp")	# padded tp[num]
111# &DWP(64+(4*$num+$pad)*1,"esp")	# padded copy of ap[num]
112# &DWP(64+(4*$num+$pad)*2,"esp")	# padded copy of bp[num]
113# &DWP(64+(4*$num+$pad)*3,"esp")	# padded copy of np[num]
114# Note that SDK suggests to unconditionally allocate 2K per vector. This
115# has quite an impact on performance. It naturally depends on key length,
116# but to give an example 1024 bit private RSA key operations suffer >30%
117# penalty. I allocate only as much as actually required...
118
119&function_begin($func);
120	&xor	("eax","eax");
121	&mov	("ecx",&wparam(5));	# num
122	# meet VIA's limitations for num [note that the specification
123	# expresses them in bits, while we work with amount of 32-bit words]
124	&test	("ecx",3);
125	&jnz	(&label("leave"));	# num % 4 != 0
126	&cmp	("ecx",8);
127	&jb	(&label("leave"));	# num < 8
128	&cmp	("ecx",1024);
129	&ja	(&label("leave"));	# num > 1024
130
131	&pushf	();
132	&cld	();
133
134	&mov	("edi",&wparam(0));	# rp
135	&mov	("eax",&wparam(1));	# ap
136	&mov	("ebx",&wparam(2));	# bp
137	&mov	("edx",&wparam(3));	# np
138	&mov	("esi",&wparam(4));	# n0
139	&mov	("esi",&DWP(0,"esi"));	# *n0
140
141	&lea	("ecx",&DWP($pad,"","ecx",4));	# ecx becomes vector size in bytes
142	&lea	("ebp",&DWP(64,"","ecx",4));	# allocate 4 vectors + 64 bytes
143	&neg	("ebp");
144	&add	("ebp","esp");
145	&and	("ebp",-64);		# align to cache-line
146	&xchg	("ebp","esp");		# alloca
147
148	&mov	($rp,"edi");		# save rp
149	&mov	($sp,"ebp");		# save esp
150
151	&mov	($mZeroPrime,"esi");
152	&lea	("esi",&DWP(64,"esp"));	# tp
153	&mov	($T,"esi");
154	&lea	("edi",&DWP(32,"esp"));	# scratch area
155	&mov	($scratch,"edi");
156	&mov	("esi","eax");
157
158	&lea	("ebp",&DWP(-$pad,"ecx"));
159	&shr	("ebp",2);		# restore original num value in ebp
160
161	&xor	("eax","eax");
162
163	&mov	("ecx","ebp");
164	&lea	("ecx",&DWP((32+$pad)/4,"ecx"));# padded tp + scratch
165	&data_byte(0xf3,0xab);		# rep stosl, bzero
166
167	&mov	("ecx","ebp");
168	&lea	("edi",&DWP(64+$pad,"esp","ecx",4));# pointer to ap copy
169	&mov	($A,"edi");
170	&data_byte(0xf3,0xa5);		# rep movsl, memcpy
171	&mov	("ecx",$pad/4);
172	&data_byte(0xf3,0xab);		# rep stosl, bzero pad
173	# edi points at the end of padded ap copy...
174
175	&mov	("ecx","ebp");
176	&mov	("esi","ebx");
177	&mov	($B,"edi");
178	&data_byte(0xf3,0xa5);		# rep movsl, memcpy
179	&mov	("ecx",$pad/4);
180	&data_byte(0xf3,0xab);		# rep stosl, bzero pad
181	# edi points at the end of padded bp copy...
182
183	&mov	("ecx","ebp");
184	&mov	("esi","edx");
185	&mov	($M,"edi");
186	&data_byte(0xf3,0xa5);		# rep movsl, memcpy
187	&mov	("ecx",$pad/4);
188	&data_byte(0xf3,0xab);		# rep stosl, bzero pad
189	# edi points at the end of padded np copy...
190
191	# let magic happen...
192	&mov	("ecx","ebp");
193	&mov	("esi","esp");
194	&shl	("ecx",5);		# convert word counter to bit counter
195	&align	(4);
196	&data_byte(0xf3,0x0f,0xa6,0xc0);# rep montmul
197
198	&mov	("ecx","ebp");
199	&lea	("esi",&DWP(64,"esp"));		# tp
200	# edi still points at the end of padded np copy...
201	&neg	("ebp");
202	&lea	("ebp",&DWP(-$pad,"edi","ebp",4));	# so just "rewind"
203	&mov	("edi",$rp);			# restore rp
204	&xor	("edx","edx");			# i=0 and clear CF
205
206&set_label("sub",8);
207	&mov	("eax",&DWP(0,"esi","edx",4));
208	&sbb	("eax",&DWP(0,"ebp","edx",4));
209	&mov	(&DWP(0,"edi","edx",4),"eax");	# rp[i]=tp[i]-np[i]
210	&lea	("edx",&DWP(1,"edx"));		# i++
211	&loop	(&label("sub"));		# doesn't affect CF!
212
213	&mov	("eax",&DWP(0,"esi","edx",4));	# upmost overflow bit
214	&sbb	("eax",0);
215
216	&mov	("ecx","edx");			# num
217	&mov	("edx",0);			# i=0
218
219&set_label("copy",8);
220	&mov	("ebx",&DWP(0,"esi","edx",4));
221	&mov	("eax",&DWP(0,"edi","edx",4));
222	&mov	(&DWP(0,"esi","edx",4),"ecx");	# zap tp
223	&cmovc	("eax","ebx");
224	&mov	(&DWP(0,"edi","edx",4),"eax");
225	&lea	("edx",&DWP(1,"edx"));		# i++
226	&loop	(&label("copy"));
227
228	&mov	("ebp",$sp);
229	&xor	("eax","eax");
230
231	&mov	("ecx",64/4);
232	&mov	("edi","esp");		# zap frame including scratch area
233	&data_byte(0xf3,0xab);		# rep stosl, bzero
234
235	# zap copies of ap, bp and np
236	&lea	("edi",&DWP(64+$pad,"esp","edx",4));# pointer to ap
237	&lea	("ecx",&DWP(3*$pad/4,"edx","edx",2));
238	&data_byte(0xf3,0xab);		# rep stosl, bzero
239
240	&mov	("esp","ebp");
241	&inc	("eax");		# signal "done"
242	&popf	();
243&set_label("leave");
244&function_end($func);
245
246&asciz("Padlock Montgomery Multiplication, CRYPTOGAMS by <appro\@openssl.org>");
247
248&asm_finish();
249
250close STDOUT or die "error closing STDOUT: $!";
251