Reserve for SMALL_FOOTPRINT bn_asm.c. Currently OPENSSL_SMALL_FOOTPRINT
authorAndy Polyakov <appro@openssl.org>
Tue, 4 Oct 2005 06:22:11 +0000 (06:22 +0000)
committerAndy Polyakov <appro@openssl.org>
Tue, 4 Oct 2005 06:22:11 +0000 (06:22 +0000)
is defined on Windows CE targets.

crypto/bn/bn.h
crypto/bn/bn_asm.c

index c296e10..f8652a4 100644 (file)
@@ -94,9 +94,11 @@ extern "C" {
 /* #define BN_DEBUG */
 /* #define BN_DEBUG_RAND */
 
+#ifndef OPENSSL_SMALL_FOOTPRINT
 #define BN_MUL_COMBA
 #define BN_SQR_COMBA
 #define BN_RECURSION
+#endif
 
 /* This next option uses the C libraries (2 word)/(1 word) function.
  * If it is not defined, I use my C version (which is slower).
index 52af96d..741cf81 100644 (file)
@@ -75,6 +75,7 @@ BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
        assert(num >= 0);
        if (num <= 0) return(c1);
 
+#ifndef OPENSSL_SMALL_FOOTPRINT
        while (num&~3)
                {
                mul_add(rp[0],ap[0],w,c1);
@@ -83,11 +84,11 @@ BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
                mul_add(rp[3],ap[3],w,c1);
                ap+=4; rp+=4; num-=4;
                }
-       if (num)
+#endif
+       while (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;
+               mul_add(rp[0],ap[0],w,c1);
+               ap++; rp++; num--;
                }
        
        return(c1);
@@ -100,6 +101,7 @@ BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
        assert(num >= 0);
        if (num <= 0) return(c1);
 
+#ifndef OPENSSL_SMALL_FOOTPRINT
        while (num&~3)
                {
                mul(rp[0],ap[0],w,c1);
@@ -108,11 +110,11 @@ BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
                mul(rp[3],ap[3],w,c1);
                ap+=4; rp+=4; num-=4;
                }
-       if (num)
+#endif
+       while (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);
+               mul(rp[0],ap[0],w,c1);
+               ap++; rp++; num--;
                }
        return(c1);
        } 
@@ -121,6 +123,8 @@ void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
         {
        assert(n >= 0);
        if (n <= 0) return;
+
+#ifndef OPENSSL_SMALL_FOOTPRINT
        while (n&~3)
                {
                sqr(r[0],r[1],a[0]);
@@ -129,11 +133,11 @@ void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
                sqr(r[6],r[7],a[3]);
                a+=4; r+=8; n-=4;
                }
-       if (n)
+#endif
+       while (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]);
+               sqr(r[0],r[1],a[0]);
+               a++; r+=2; n--;
                }
        }
 
@@ -150,18 +154,20 @@ BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
        bl=LBITS(w);
        bh=HBITS(w);
 
-       for (;;)
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (num&~3)
                {
                mul_add(rp[0],ap[0],bl,bh,c);
-               if (--num == 0) break;
                mul_add(rp[1],ap[1],bl,bh,c);
-               if (--num == 0) break;
                mul_add(rp[2],ap[2],bl,bh,c);
-               if (--num == 0) break;
                mul_add(rp[3],ap[3],bl,bh,c);
-               if (--num == 0) break;
-               ap+=4;
-               rp+=4;
+               ap+=4; rp+=4; num-=4;
+               }
+#endif
+       while (num)
+               {
+               mul_add(rp[0],ap[0],bl,bh,c);
+               ap++; rp++; num--;
                }
        return(c);
        } 
@@ -177,18 +183,20 @@ BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
        bl=LBITS(w);
        bh=HBITS(w);
 
-       for (;;)
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (num&~3)
                {
                mul(rp[0],ap[0],bl,bh,carry);
-               if (--num == 0) break;
                mul(rp[1],ap[1],bl,bh,carry);
-               if (--num == 0) break;
                mul(rp[2],ap[2],bl,bh,carry);
-               if (--num == 0) break;
                mul(rp[3],ap[3],bl,bh,carry);
-               if (--num == 0) break;
-               ap+=4;
-               rp+=4;
+               ap+=4; rp+=4; num-=4;
+               }
+#endif
+       while (num)
+               {
+               mul(rp[0],ap[0],bl,bh,carry);
+               ap++; rp++; num--;
                }
        return(carry);
        } 
@@ -197,22 +205,21 @@ void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
         {
        assert(n >= 0);
        if (n <= 0) return;
-       for (;;)
+
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (n&~3)
                {
                sqr64(r[0],r[1],a[0]);
-               if (--n == 0) break;
-
                sqr64(r[2],r[3],a[1]);
-               if (--n == 0) break;
-
                sqr64(r[4],r[5],a[2]);
-               if (--n == 0) break;
-
                sqr64(r[6],r[7],a[3]);
-               if (--n == 0) break;
-
-               a+=4;
-               r+=8;
+               a+=4; r+=8; n-=4;
+               }
+#endif
+       while (n)
+               {
+               sqr64(r[0],r[1],a[0]);
+               a++; r+=2; n--;
                }
        }
 
@@ -303,31 +310,30 @@ BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
        assert(n >= 0);
        if (n <= 0) return((BN_ULONG)0);
 
-       for (;;)
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (n&~3)
                {
                ll+=(BN_ULLONG)a[0]+b[0];
                r[0]=(BN_ULONG)ll&BN_MASK2;
                ll>>=BN_BITS2;
-               if (--n <= 0) break;
-
                ll+=(BN_ULLONG)a[1]+b[1];
                r[1]=(BN_ULONG)ll&BN_MASK2;
                ll>>=BN_BITS2;
-               if (--n <= 0) break;
-
                ll+=(BN_ULLONG)a[2]+b[2];
                r[2]=(BN_ULONG)ll&BN_MASK2;
                ll>>=BN_BITS2;
-               if (--n <= 0) break;
-
                ll+=(BN_ULLONG)a[3]+b[3];
                r[3]=(BN_ULONG)ll&BN_MASK2;
                ll>>=BN_BITS2;
-               if (--n <= 0) break;
-
-               a+=4;
-               b+=4;
-               r+=4;
+               a+=4; b+=4; r+=4; n-=4;
+               }
+#endif
+       while (n)
+               {
+               ll+=(BN_ULLONG)a[0]+b[0];
+               r[0]=(BN_ULONG)ll&BN_MASK2;
+               ll>>=BN_BITS2;
+               a++; b++; r++; n--;
                }
        return((BN_ULONG)ll);
        }
@@ -340,7 +346,8 @@ BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
        if (n <= 0) return((BN_ULONG)0);
 
        c=0;
-       for (;;)
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (n&~3)
                {
                t=a[0];
                t=(t+c)&BN_MASK2;
@@ -348,35 +355,36 @@ BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
                l=(t+b[0])&BN_MASK2;
                c+=(l < t);
                r[0]=l;
-               if (--n <= 0) break;
-
                t=a[1];
                t=(t+c)&BN_MASK2;
                c=(t < c);
                l=(t+b[1])&BN_MASK2;
                c+=(l < t);
                r[1]=l;
-               if (--n <= 0) break;
-
                t=a[2];
                t=(t+c)&BN_MASK2;
                c=(t < c);
                l=(t+b[2])&BN_MASK2;
                c+=(l < t);
                r[2]=l;
-               if (--n <= 0) break;
-
                t=a[3];
                t=(t+c)&BN_MASK2;
                c=(t < c);
                l=(t+b[3])&BN_MASK2;
                c+=(l < t);
                r[3]=l;
-               if (--n <= 0) break;
-
-               a+=4;
-               b+=4;
-               r+=4;
+               a+=4; b+=4; r+=4; n-=4;
+               }
+#endif
+       while(n)
+               {
+               t=a[0];
+               t=(t+c)&BN_MASK2;
+               c=(t < c);
+               l=(t+b[0])&BN_MASK2;
+               c+=(l < t);
+               r[0]=l;
+               a++; b++; r++; n--;
                }
        return((BN_ULONG)c);
        }
@@ -390,36 +398,35 @@ BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
        assert(n >= 0);
        if (n <= 0) return((BN_ULONG)0);
 
-       for (;;)
+#ifndef OPENSSL_SMALL_FOOTPRINT
+       while (n&~3)
                {
                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;
+               a+=4; b+=4; r+=4; n-=4;
+               }
+#endif
+       while (n)
+               {
+               t1=a[0]; t2=b[0];
+               r[0]=(t1-t2-c)&BN_MASK2;
+               if (t1 != t2) c=(t1 < t2);
+               a++; b++; r++; n--;
                }
        return(c);
        }
 
-#ifdef BN_MUL_COMBA
+#if defined(BN_MUL_COMBA) && !defined(OPENSSL_SMALL_FOOTPRINT)
 
 #undef bn_mul_comba8
 #undef bn_mul_comba4
@@ -826,7 +833,7 @@ void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
  * This is essentially reference implementation, which may or may not
  * result in performance improvement. E.g. on IA-32 this does give 40%
  * faster rsa1024 private key operations and 10% faster rsa4096 ones,
- * while on AMD64 it improves rsa1024 sign only by 10%, but *worsens*
+ * while on AMD64 it improves rsa1024 sign only by 10% and *worsens*
  * rsa4096 sign by 15%. Once again, it's a reference implementation,
  * one to be used as start-point for platform-specific assembler.
  */