3 # ====================================================================
4 # Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
5 # project. The module is, however, dual licensed under OpenSSL and
6 # CRYPTOGAMS licenses depending on where you obtain it. For further
7 # details see http://www.openssl.org/~appro/cryptogams/.
8 # ====================================================================
12 # The module implements bn_GF2m_mul_2x2 polynomial multiplication
13 # used in bn_gf2m.c. It's kind of low-hanging mechanical port from
14 # C for the time being... Except that it has two code paths: pure
15 # integer code suitable for any ARMv4 and later CPU and NEON code
16 # suitable for ARMv7. Pure integer 1x1 multiplication subroutine runs
17 # in ~45 cycles on dual-issue core such as Cortex A8, which is ~50%
18 # faster than compiler-generated code. For ECDH and ECDSA verify (but
19 # not for ECDSA sign) it means 25%-45% improvement depending on key
20 # length, more for longer keys. Even though NEON 1x1 multiplication
21 # runs in even less cycles, ~30, improvement is measurable only on
22 # longer keys. One has to optimize code elsewhere to get NEON glow...
24 while (($output=shift) && ($output!~/^\w[\w\-]*\.\w+$/)) {}
25 open STDOUT,">$output";
27 sub Dlo() { shift=~m|q([1]?[0-9])|?"d".($1*2):""; }
28 sub Dhi() { shift=~m|q([1]?[0-9])|?"d".($1*2+1):""; }
29 sub Q() { shift=~m|d([1-3]?[02468])|?"q".($1/2):""; }
40 .type mul_1x1_neon,%function
43 vshl.u64 `&Dlo("q1")`,d16,#8 @ q1-q3 are slided $a
44 vmull.p8 `&Q("d0")`,d16,d17 @ a·bb
45 vshl.u64 `&Dlo("q2")`,d16,#16
46 vmull.p8 q1,`&Dlo("q1")`,d17 @ a<<8·bb
47 vshl.u64 `&Dlo("q3")`,d16,#24
48 vmull.p8 q2,`&Dlo("q2")`,d17 @ a<<16·bb
49 vshr.u64 `&Dlo("q1")`,#8
50 vmull.p8 q3,`&Dlo("q3")`,d17 @ a<<24·bb
51 vshl.u64 `&Dhi("q1")`,#24
53 vshr.u64 `&Dlo("q2")`,#16
55 vshl.u64 `&Dhi("q2")`,#16
57 vshr.u64 `&Dlo("q3")`,#24
59 vshl.u64 `&Dhi("q3")`,#8
63 .size mul_1x1_neon,.-mul_1x1_neon
67 # private interface to mul_1x1_ialu
72 ($a0,$a1,$a2,$a12,$a4,$a14)=
73 ($hi,$lo,$t0,$t1, $i0,$i1 )=map("r$_",(4..9),12);
78 .type mul_1x1_ialu,%function
82 bic $a1,$a,#3<<30 @ a1=a&0x3fffffff
83 str $a0,[sp,#0] @ tab[0]=0
84 add $a2,$a1,$a1 @ a2=a1<<1
85 str $a1,[sp,#4] @ tab[1]=a1
86 eor $a12,$a1,$a2 @ a1^a2
87 str $a2,[sp,#8] @ tab[2]=a2
88 mov $a4,$a1,lsl#2 @ a4=a1<<2
89 str $a12,[sp,#12] @ tab[3]=a1^a2
90 eor $a14,$a1,$a4 @ a1^a4
91 str $a4,[sp,#16] @ tab[4]=a4
92 eor $a0,$a2,$a4 @ a2^a4
93 str $a14,[sp,#20] @ tab[5]=a1^a4
94 eor $a12,$a12,$a4 @ a1^a2^a4
95 str $a0,[sp,#24] @ tab[6]=a2^a4
96 and $i0,$mask,$b,lsl#2
97 str $a12,[sp,#28] @ tab[7]=a1^a2^a4
99 and $i1,$mask,$b,lsr#1
100 ldr $lo,[sp,$i0] @ tab[b & 0x7]
101 and $i0,$mask,$b,lsr#4
102 ldr $t1,[sp,$i1] @ tab[b >> 3 & 0x7]
103 and $i1,$mask,$b,lsr#7
104 ldr $t0,[sp,$i0] @ tab[b >> 6 & 0x7]
105 eor $lo,$lo,$t1,lsl#3 @ stall
107 ldr $t1,[sp,$i1] @ tab[b >> 9 & 0x7]
109 and $i0,$mask,$b,lsr#10
110 eor $lo,$lo,$t0,lsl#6
111 eor $hi,$hi,$t0,lsr#26
112 ldr $t0,[sp,$i0] @ tab[b >> 12 & 0x7]
114 and $i1,$mask,$b,lsr#13
115 eor $lo,$lo,$t1,lsl#9
116 eor $hi,$hi,$t1,lsr#23
117 ldr $t1,[sp,$i1] @ tab[b >> 15 & 0x7]
119 and $i0,$mask,$b,lsr#16
120 eor $lo,$lo,$t0,lsl#12
121 eor $hi,$hi,$t0,lsr#20
122 ldr $t0,[sp,$i0] @ tab[b >> 18 & 0x7]
124 and $i1,$mask,$b,lsr#19
125 eor $lo,$lo,$t1,lsl#15
126 eor $hi,$hi,$t1,lsr#17
127 ldr $t1,[sp,$i1] @ tab[b >> 21 & 0x7]
129 and $i0,$mask,$b,lsr#22
130 eor $lo,$lo,$t0,lsl#18
131 eor $hi,$hi,$t0,lsr#14
132 ldr $t0,[sp,$i0] @ tab[b >> 24 & 0x7]
134 and $i1,$mask,$b,lsr#25
135 eor $lo,$lo,$t1,lsl#21
136 eor $hi,$hi,$t1,lsr#11
137 ldr $t1,[sp,$i1] @ tab[b >> 27 & 0x7]
140 and $i0,$mask,$b,lsr#28
141 eor $lo,$lo,$t0,lsl#24
142 eor $hi,$hi,$t0,lsr#8
143 ldr $t0,[sp,$i0] @ tab[b >> 30 ]
145 eorne $lo,$lo,$b,lsl#30
146 eorne $hi,$hi,$b,lsr#2
148 eor $lo,$lo,$t1,lsl#27
149 eor $hi,$hi,$t1,lsr#5
150 eorne $lo,$lo,$b,lsl#31
151 eorne $hi,$hi,$b,lsr#1
152 eor $lo,$lo,$t0,lsl#30
153 eor $hi,$hi,$t0,lsr#2
156 .size mul_1x1_ialu,.-mul_1x1_ialu
159 # void bn_GF2m_mul_2x2(BN_ULONG *r,
160 # BN_ULONG a1,BN_ULONG a0,
161 # BN_ULONG b1,BN_ULONG b0); # r[3..0]=a1a0·b1b0
163 ($A1,$B1,$A0,$B0,$A1B1,$A0B0)=map("d$_",(18..23));
166 .global bn_GF2m_mul_2x2
167 .type bn_GF2m_mul_2x2,%function
171 ldr r12,.LOPENSSL_armcap
172 .Lpic: ldr r12,[pc,r12]
177 vmov.32 $B1,r3,r3 @ two copies of b1
178 vmov.32 ${A1}[0],r1 @ a1
181 vld1.32 ${B0}[],[sp,:32] @ two copies of b0
182 vmov.32 ${A0}[0],r2 @ a0
187 bl mul_1x1_neon @ a1·b1
192 bl mul_1x1_neon @ a0·b0
198 bl mul_1x1_neon @ (a0+a1)·(b0+b1)
200 veor d0,$A0 @ (a0+a1)·(b0+b1)-a0·b0-a1·b1
205 vst1.32 {${A0B0}[0]},[r0,:32]!
206 vst1.32 {${A0B0}[1]},[r0,:32]!
207 vst1.32 {${A1B1}[0]},[r0,:32]!
208 vst1.32 {${A1B1}[1]},[r0,:32]
214 $ret="r10"; # reassigned 1st argument
216 stmdb sp!,{r4-r10,lr}
217 mov $ret,r0 @ reassign 1st argument
219 ldr r3,[sp,#32] @ load b0
221 sub sp,sp,#32 @ allocate tab[8]
223 bl mul_1x1_ialu @ a1·b1
227 eor $b,$b,r3 @ flip b0 and b1
228 eor $a,$a,r2 @ flip a0 and a1
233 bl mul_1x1_ialu @ a0·b0
239 bl mul_1x1_ialu @ (a1+a0)·(b1+b0)
241 @r=map("r$_",(6..9));
243 ldmia $ret,{@r[0]-@r[3]}
252 add sp,sp,#32 @ destroy tab[8]
256 ldmia sp!,{r4-r10,pc}
258 ldmia sp!,{r4-r10,lr}
260 moveq pc,lr @ be binary compatible with V4, yet
261 bx lr @ interoperable with Thumb ISA:-)
263 .size bn_GF2m_mul_2x2,.-bn_GF2m_mul_2x2
267 .word OPENSSL_armcap_P-(.Lpic+8)
269 .asciz "GF(2^m) Multiplication for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
272 .comm OPENSSL_armcap_P,4,4
275 $code =~ s/\`([^\`]*)\`/eval $1/gem;
276 $code =~ s/\bbx\s+lr\b/.word\t0xe12fff1e/gm; # make it possible to compile with -march=armv4
278 close STDOUT; # enforce flush