openssl/crypto/bn/asm/x86_64-gcc.c
Adam Langley 7753a3a684 Add volatile qualifications to two blocks of inline asm to stop GCC from
eliminating them as dead code.

Both volatile and "memory" are used because of some concern that the compiler
may still cache values across the asm block without it, and because this was
such a painful debugging session that I wanted to ensure that it's never
repeated.
2013-06-04 18:46:25 +01:00

609 lines
13 KiB
C
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#include "../bn_lcl.h"
#if !(defined(__GNUC__) && __GNUC__>=2)
# include "../bn_asm.c" /* kind of dirty hack for Sun Studio */
#else
/*
* x86_64 BIGNUM accelerator version 0.1, December 2002.
*
* Implemented by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
* project.
*
* Rights for redistribution and usage in source and binary forms are
* granted according to the OpenSSL license. Warranty of any kind is
* disclaimed.
*
* Q. Version 0.1? It doesn't sound like Andy, he used to assign real
* versions, like 1.0...
* A. Well, that's because this code is basically a quick-n-dirty
* proof-of-concept hack. As you can see it's implemented with
* inline assembler, which means that you're bound to GCC and that
* there might be enough room for further improvement.
*
* Q. Why inline assembler?
* A. x86_64 features own ABI which I'm not familiar with. This is
* why I decided to let the compiler take care of subroutine
* prologue/epilogue as well as register allocation. For reference.
* Win64 implements different ABI for AMD64, different from Linux.
*
* Q. How much faster does it get?
* A. 'apps/openssl speed rsa dsa' output with no-asm:
*
* sign verify sign/s verify/s
* rsa 512 bits 0.0006s 0.0001s 1683.8 18456.2
* rsa 1024 bits 0.0028s 0.0002s 356.0 6407.0
* rsa 2048 bits 0.0172s 0.0005s 58.0 1957.8
* rsa 4096 bits 0.1155s 0.0018s 8.7 555.6
* sign verify sign/s verify/s
* dsa 512 bits 0.0005s 0.0006s 2100.8 1768.3
* dsa 1024 bits 0.0014s 0.0018s 692.3 559.2
* dsa 2048 bits 0.0049s 0.0061s 204.7 165.0
*
* 'apps/openssl speed rsa dsa' output with this module:
*
* sign verify sign/s verify/s
* rsa 512 bits 0.0004s 0.0000s 2767.1 33297.9
* rsa 1024 bits 0.0012s 0.0001s 867.4 14674.7
* rsa 2048 bits 0.0061s 0.0002s 164.0 5270.0
* rsa 4096 bits 0.0384s 0.0006s 26.1 1650.8
* sign verify sign/s verify/s
* dsa 512 bits 0.0002s 0.0003s 4442.2 3786.3
* dsa 1024 bits 0.0005s 0.0007s 1835.1 1497.4
* dsa 2048 bits 0.0016s 0.0020s 620.4 504.6
*
* For the reference. IA-32 assembler implementation performs
* very much like 64-bit code compiled with no-asm on the same
* machine.
*/
#if defined(_WIN64) || !defined(__LP64__)
#define BN_ULONG unsigned long long
#else
#define BN_ULONG unsigned long
#endif
#undef mul
#undef mul_add
/*
* "m"(a), "+m"(r) is the way to favor DirectPath <20>-code;
* "g"(0) let the compiler to decide where does it
* want to keep the value of zero;
*/
#define mul_add(r,a,word,carry) do { \
register BN_ULONG high,low; \
asm ("mulq %3" \
: "=a"(low),"=d"(high) \
: "a"(word),"m"(a) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(carry),"+d"(high)\
: "a"(low),"g"(0) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+m"(r),"+d"(high) \
: "r"(carry),"g"(0) \
: "cc"); \
carry=high; \
} while (0)
#define mul(r,a,word,carry) do { \
register BN_ULONG high,low; \
asm ("mulq %3" \
: "=a"(low),"=d"(high) \
: "a"(word),"g"(a) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(carry),"+d"(high)\
: "a"(low),"g"(0) \
: "cc"); \
(r)=carry, carry=high; \
} while (0)
#undef sqr
#define sqr(r0,r1,a) \
asm ("mulq %2" \
: "=a"(r0),"=d"(r1) \
: "a"(a) \
: "cc");
BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
{
BN_ULONG c1=0;
if (num <= 0) return(c1);
while (num&~3)
{
mul_add(rp[0],ap[0],w,c1);
mul_add(rp[1],ap[1],w,c1);
mul_add(rp[2],ap[2],w,c1);
mul_add(rp[3],ap[3],w,c1);
ap+=4; rp+=4; num-=4;
}
if (num)
{
mul_add(rp[0],ap[0],w,c1); if (--num==0) return c1;
mul_add(rp[1],ap[1],w,c1); if (--num==0) return c1;
mul_add(rp[2],ap[2],w,c1); return c1;
}
return(c1);
}
BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
{
BN_ULONG c1=0;
if (num <= 0) return(c1);
while (num&~3)
{
mul(rp[0],ap[0],w,c1);
mul(rp[1],ap[1],w,c1);
mul(rp[2],ap[2],w,c1);
mul(rp[3],ap[3],w,c1);
ap+=4; rp+=4; num-=4;
}
if (num)
{
mul(rp[0],ap[0],w,c1); if (--num == 0) return c1;
mul(rp[1],ap[1],w,c1); if (--num == 0) return c1;
mul(rp[2],ap[2],w,c1);
}
return(c1);
}
void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
{
if (n <= 0) return;
while (n&~3)
{
sqr(r[0],r[1],a[0]);
sqr(r[2],r[3],a[1]);
sqr(r[4],r[5],a[2]);
sqr(r[6],r[7],a[3]);
a+=4; r+=8; n-=4;
}
if (n)
{
sqr(r[0],r[1],a[0]); if (--n == 0) return;
sqr(r[2],r[3],a[1]); if (--n == 0) return;
sqr(r[4],r[5],a[2]);
}
}
BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
{ BN_ULONG ret,waste;
asm ("divq %4"
: "=a"(ret),"=d"(waste)
: "a"(l),"d"(h),"g"(d)
: "cc");
return ret;
}
BN_ULONG bn_add_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int n)
{ BN_ULONG ret;
size_t i=0;
if (n <= 0) return 0;
asm volatile (
" subq %0,%0 \n" /* clear carry */
" jmp 1f \n"
".p2align 4 \n"
"1: movq (%4,%2,8),%0 \n"
" adcq (%5,%2,8),%0 \n"
" movq %0,(%3,%2,8) \n"
" lea 1(%2),%2 \n"
" loop 1b \n"
" sbbq %0,%0 \n"
: "=&r"(ret),"+c"(n),"+r"(i)
: "r"(rp),"r"(ap),"r"(bp)
: "cc", "memory"
);
return ret&1;
}
#ifndef SIMICS
BN_ULONG bn_sub_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int n)
{ BN_ULONG ret;
size_t i=0;
if (n <= 0) return 0;
asm volatile (
" subq %0,%0 \n" /* clear borrow */
" jmp 1f \n"
".p2align 4 \n"
"1: movq (%4,%2,8),%0 \n"
" sbbq (%5,%2,8),%0 \n"
" movq %0,(%3,%2,8) \n"
" lea 1(%2),%2 \n"
" loop 1b \n"
" sbbq %0,%0 \n"
: "=&r"(ret),"+c"(n),"+r"(i)
: "r"(rp),"r"(ap),"r"(bp)
: "cc", "memory"
);
return ret&1;
}
#else
/* Simics 1.4<7 has buggy sbbq:-( */
#define BN_MASK2 0xffffffffffffffffL
BN_ULONG bn_sub_words(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n)
{
BN_ULONG t1,t2;
int c=0;
if (n <= 0) return((BN_ULONG)0);
for (;;)
{
t1=a[0]; t2=b[0];
r[0]=(t1-t2-c)&BN_MASK2;
if (t1 != t2) c=(t1 < t2);
if (--n <= 0) break;
t1=a[1]; t2=b[1];
r[1]=(t1-t2-c)&BN_MASK2;
if (t1 != t2) c=(t1 < t2);
if (--n <= 0) break;
t1=a[2]; t2=b[2];
r[2]=(t1-t2-c)&BN_MASK2;
if (t1 != t2) c=(t1 < t2);
if (--n <= 0) break;
t1=a[3]; t2=b[3];
r[3]=(t1-t2-c)&BN_MASK2;
if (t1 != t2) c=(t1 < t2);
if (--n <= 0) break;
a+=4;
b+=4;
r+=4;
}
return(c);
}
#endif
/* mul_add_c(a,b,c0,c1,c2) -- c+=a*b for three word number c=(c2,c1,c0) */
/* mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0) */
/* sqr_add_c(a,i,c0,c1,c2) -- c+=a[i]^2 for three word number c=(c2,c1,c0) */
/* sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number c=(c2,c1,c0) */
#if 0
/* original macros are kept for reference purposes */
#define mul_add_c(a,b,c0,c1,c2) { \
BN_ULONG ta=(a),tb=(b); \
t1 = ta * tb; \
t2 = BN_UMULT_HIGH(ta,tb); \
c0 += t1; t2 += (c0<t1)?1:0; \
c1 += t2; c2 += (c1<t2)?1:0; \
}
#define mul_add_c2(a,b,c0,c1,c2) { \
BN_ULONG ta=(a),tb=(b),t0; \
t1 = BN_UMULT_HIGH(ta,tb); \
t0 = ta * tb; \
t2 = t1+t1; c2 += (t2<t1)?1:0; \
t1 = t0+t0; t2 += (t1<t0)?1:0; \
c0 += t1; t2 += (c0<t1)?1:0; \
c1 += t2; c2 += (c1<t2)?1:0; \
}
#else
#define mul_add_c(a,b,c0,c1,c2) do { \
asm ("mulq %3" \
: "=a"(t1),"=d"(t2) \
: "a"(a),"m"(b) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c0),"+d"(t2) \
: "a"(t1),"g"(0) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c1),"+r"(c2) \
: "d"(t2),"g"(0) \
: "cc"); \
} while (0)
#define sqr_add_c(a,i,c0,c1,c2) do { \
asm ("mulq %2" \
: "=a"(t1),"=d"(t2) \
: "a"(a[i]) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c0),"+d"(t2) \
: "a"(t1),"g"(0) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c1),"+r"(c2) \
: "d"(t2),"g"(0) \
: "cc"); \
} while (0)
#define mul_add_c2(a,b,c0,c1,c2) do { \
asm ("mulq %3" \
: "=a"(t1),"=d"(t2) \
: "a"(a),"m"(b) \
: "cc"); \
asm ("addq %0,%0; adcq %2,%1" \
: "+d"(t2),"+r"(c2) \
: "g"(0) \
: "cc"); \
asm ("addq %0,%0; adcq %2,%1" \
: "+a"(t1),"+d"(t2) \
: "g"(0) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c0),"+d"(t2) \
: "a"(t1),"g"(0) \
: "cc"); \
asm ("addq %2,%0; adcq %3,%1" \
: "+r"(c1),"+r"(c2) \
: "d"(t2),"g"(0) \
: "cc"); \
} while (0)
#endif
#define sqr_add_c2(a,i,j,c0,c1,c2) \
mul_add_c2((a)[i],(a)[j],c0,c1,c2)
void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
{
BN_ULONG t1,t2;
BN_ULONG c1,c2,c3;
c1=0;
c2=0;
c3=0;
mul_add_c(a[0],b[0],c1,c2,c3);
r[0]=c1;
c1=0;
mul_add_c(a[0],b[1],c2,c3,c1);
mul_add_c(a[1],b[0],c2,c3,c1);
r[1]=c2;
c2=0;
mul_add_c(a[2],b[0],c3,c1,c2);
mul_add_c(a[1],b[1],c3,c1,c2);
mul_add_c(a[0],b[2],c3,c1,c2);
r[2]=c3;
c3=0;
mul_add_c(a[0],b[3],c1,c2,c3);
mul_add_c(a[1],b[2],c1,c2,c3);
mul_add_c(a[2],b[1],c1,c2,c3);
mul_add_c(a[3],b[0],c1,c2,c3);
r[3]=c1;
c1=0;
mul_add_c(a[4],b[0],c2,c3,c1);
mul_add_c(a[3],b[1],c2,c3,c1);
mul_add_c(a[2],b[2],c2,c3,c1);
mul_add_c(a[1],b[3],c2,c3,c1);
mul_add_c(a[0],b[4],c2,c3,c1);
r[4]=c2;
c2=0;
mul_add_c(a[0],b[5],c3,c1,c2);
mul_add_c(a[1],b[4],c3,c1,c2);
mul_add_c(a[2],b[3],c3,c1,c2);
mul_add_c(a[3],b[2],c3,c1,c2);
mul_add_c(a[4],b[1],c3,c1,c2);
mul_add_c(a[5],b[0],c3,c1,c2);
r[5]=c3;
c3=0;
mul_add_c(a[6],b[0],c1,c2,c3);
mul_add_c(a[5],b[1],c1,c2,c3);
mul_add_c(a[4],b[2],c1,c2,c3);
mul_add_c(a[3],b[3],c1,c2,c3);
mul_add_c(a[2],b[4],c1,c2,c3);
mul_add_c(a[1],b[5],c1,c2,c3);
mul_add_c(a[0],b[6],c1,c2,c3);
r[6]=c1;
c1=0;
mul_add_c(a[0],b[7],c2,c3,c1);
mul_add_c(a[1],b[6],c2,c3,c1);
mul_add_c(a[2],b[5],c2,c3,c1);
mul_add_c(a[3],b[4],c2,c3,c1);
mul_add_c(a[4],b[3],c2,c3,c1);
mul_add_c(a[5],b[2],c2,c3,c1);
mul_add_c(a[6],b[1],c2,c3,c1);
mul_add_c(a[7],b[0],c2,c3,c1);
r[7]=c2;
c2=0;
mul_add_c(a[7],b[1],c3,c1,c2);
mul_add_c(a[6],b[2],c3,c1,c2);
mul_add_c(a[5],b[3],c3,c1,c2);
mul_add_c(a[4],b[4],c3,c1,c2);
mul_add_c(a[3],b[5],c3,c1,c2);
mul_add_c(a[2],b[6],c3,c1,c2);
mul_add_c(a[1],b[7],c3,c1,c2);
r[8]=c3;
c3=0;
mul_add_c(a[2],b[7],c1,c2,c3);
mul_add_c(a[3],b[6],c1,c2,c3);
mul_add_c(a[4],b[5],c1,c2,c3);
mul_add_c(a[5],b[4],c1,c2,c3);
mul_add_c(a[6],b[3],c1,c2,c3);
mul_add_c(a[7],b[2],c1,c2,c3);
r[9]=c1;
c1=0;
mul_add_c(a[7],b[3],c2,c3,c1);
mul_add_c(a[6],b[4],c2,c3,c1);
mul_add_c(a[5],b[5],c2,c3,c1);
mul_add_c(a[4],b[6],c2,c3,c1);
mul_add_c(a[3],b[7],c2,c3,c1);
r[10]=c2;
c2=0;
mul_add_c(a[4],b[7],c3,c1,c2);
mul_add_c(a[5],b[6],c3,c1,c2);
mul_add_c(a[6],b[5],c3,c1,c2);
mul_add_c(a[7],b[4],c3,c1,c2);
r[11]=c3;
c3=0;
mul_add_c(a[7],b[5],c1,c2,c3);
mul_add_c(a[6],b[6],c1,c2,c3);
mul_add_c(a[5],b[7],c1,c2,c3);
r[12]=c1;
c1=0;
mul_add_c(a[6],b[7],c2,c3,c1);
mul_add_c(a[7],b[6],c2,c3,c1);
r[13]=c2;
c2=0;
mul_add_c(a[7],b[7],c3,c1,c2);
r[14]=c3;
r[15]=c1;
}
void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
{
BN_ULONG t1,t2;
BN_ULONG c1,c2,c3;
c1=0;
c2=0;
c3=0;
mul_add_c(a[0],b[0],c1,c2,c3);
r[0]=c1;
c1=0;
mul_add_c(a[0],b[1],c2,c3,c1);
mul_add_c(a[1],b[0],c2,c3,c1);
r[1]=c2;
c2=0;
mul_add_c(a[2],b[0],c3,c1,c2);
mul_add_c(a[1],b[1],c3,c1,c2);
mul_add_c(a[0],b[2],c3,c1,c2);
r[2]=c3;
c3=0;
mul_add_c(a[0],b[3],c1,c2,c3);
mul_add_c(a[1],b[2],c1,c2,c3);
mul_add_c(a[2],b[1],c1,c2,c3);
mul_add_c(a[3],b[0],c1,c2,c3);
r[3]=c1;
c1=0;
mul_add_c(a[3],b[1],c2,c3,c1);
mul_add_c(a[2],b[2],c2,c3,c1);
mul_add_c(a[1],b[3],c2,c3,c1);
r[4]=c2;
c2=0;
mul_add_c(a[2],b[3],c3,c1,c2);
mul_add_c(a[3],b[2],c3,c1,c2);
r[5]=c3;
c3=0;
mul_add_c(a[3],b[3],c1,c2,c3);
r[6]=c1;
r[7]=c2;
}
void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a)
{
BN_ULONG t1,t2;
BN_ULONG c1,c2,c3;
c1=0;
c2=0;
c3=0;
sqr_add_c(a,0,c1,c2,c3);
r[0]=c1;
c1=0;
sqr_add_c2(a,1,0,c2,c3,c1);
r[1]=c2;
c2=0;
sqr_add_c(a,1,c3,c1,c2);
sqr_add_c2(a,2,0,c3,c1,c2);
r[2]=c3;
c3=0;
sqr_add_c2(a,3,0,c1,c2,c3);
sqr_add_c2(a,2,1,c1,c2,c3);
r[3]=c1;
c1=0;
sqr_add_c(a,2,c2,c3,c1);
sqr_add_c2(a,3,1,c2,c3,c1);
sqr_add_c2(a,4,0,c2,c3,c1);
r[4]=c2;
c2=0;
sqr_add_c2(a,5,0,c3,c1,c2);
sqr_add_c2(a,4,1,c3,c1,c2);
sqr_add_c2(a,3,2,c3,c1,c2);
r[5]=c3;
c3=0;
sqr_add_c(a,3,c1,c2,c3);
sqr_add_c2(a,4,2,c1,c2,c3);
sqr_add_c2(a,5,1,c1,c2,c3);
sqr_add_c2(a,6,0,c1,c2,c3);
r[6]=c1;
c1=0;
sqr_add_c2(a,7,0,c2,c3,c1);
sqr_add_c2(a,6,1,c2,c3,c1);
sqr_add_c2(a,5,2,c2,c3,c1);
sqr_add_c2(a,4,3,c2,c3,c1);
r[7]=c2;
c2=0;
sqr_add_c(a,4,c3,c1,c2);
sqr_add_c2(a,5,3,c3,c1,c2);
sqr_add_c2(a,6,2,c3,c1,c2);
sqr_add_c2(a,7,1,c3,c1,c2);
r[8]=c3;
c3=0;
sqr_add_c2(a,7,2,c1,c2,c3);
sqr_add_c2(a,6,3,c1,c2,c3);
sqr_add_c2(a,5,4,c1,c2,c3);
r[9]=c1;
c1=0;
sqr_add_c(a,5,c2,c3,c1);
sqr_add_c2(a,6,4,c2,c3,c1);
sqr_add_c2(a,7,3,c2,c3,c1);
r[10]=c2;
c2=0;
sqr_add_c2(a,7,4,c3,c1,c2);
sqr_add_c2(a,6,5,c3,c1,c2);
r[11]=c3;
c3=0;
sqr_add_c(a,6,c1,c2,c3);
sqr_add_c2(a,7,5,c1,c2,c3);
r[12]=c1;
c1=0;
sqr_add_c2(a,7,6,c2,c3,c1);
r[13]=c2;
c2=0;
sqr_add_c(a,7,c3,c1,c2);
r[14]=c3;
r[15]=c1;
}
void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
{
BN_ULONG t1,t2;
BN_ULONG c1,c2,c3;
c1=0;
c2=0;
c3=0;
sqr_add_c(a,0,c1,c2,c3);
r[0]=c1;
c1=0;
sqr_add_c2(a,1,0,c2,c3,c1);
r[1]=c2;
c2=0;
sqr_add_c(a,1,c3,c1,c2);
sqr_add_c2(a,2,0,c3,c1,c2);
r[2]=c3;
c3=0;
sqr_add_c2(a,3,0,c1,c2,c3);
sqr_add_c2(a,2,1,c1,c2,c3);
r[3]=c1;
c1=0;
sqr_add_c(a,2,c2,c3,c1);
sqr_add_c2(a,3,1,c2,c3,c1);
r[4]=c2;
c2=0;
sqr_add_c2(a,3,2,c3,c1,c2);
r[5]=c3;
c3=0;
sqr_add_c(a,3,c1,c2,c3);
r[6]=c1;
r[7]=c2;
}
#endif