ref: 87abbc649f9064660128b840ef3aabad3e55abce
parent: 5f155322607bb8771881961a2fed71bb3dea8cf1
author: aiju <devnull@localhost>
date: Tue Dec 8 13:29:22 EST 2015
mp: add logic operations; mpfmt: include 0x with #
--- a/sys/include/mp.h
+++ b/sys/include/mp.h
@@ -76,6 +76,15 @@
void mpexp(mpint *b, mpint *e, mpint *m, mpint *res); /* res = b**e mod m */
void mpmod(mpint *b, mpint *m, mpint *remainder); /* remainder = b mod m */
+/* logical operations */
+void mpand(mpint *b1, mpint *b2, mpint *res);
+void mpbic(mpint *b1, mpint *b2, mpint *res);
+void mpor(mpint *b1, mpint *b2, mpint *res);
+void mpnot(mpint *b, mpint *res);
+void mpxor(mpint *b1, mpint *b2, mpint *res);
+void mptrunc(mpint *b, int n, mpint *res);
+void mpxtend(mpint *b, int n, mpint *res);
+
/* modular arithmetic, time invariant when 0≤b1≤m-1 and 0≤b2≤m-1 */
void mpmodadd(mpint *b1, mpint *b2, mpint *m, mpint *sum); /* sum = b1+b2 % m */
void mpmodsub(mpint *b1, mpint *b2, mpint *m, mpint *diff); /* diff = b1-b2 % m */
--- a/sys/src/libmp/port/mpfmt.c
+++ b/sys/src/libmp/port/mpfmt.c
@@ -146,7 +146,13 @@
if(p == nil)
return fmtstrcpy(fmt, "*");
else{- fmtstrcpy(fmt, p);
+ if((fmt->flags & FmtSharp) != 0 && fmt->prec!=10 && fmt->prec!=32 && fmt->prec!=64)
+ if(*p == '-')
+ fmtprint(fmt, "-0x%s", p + 1);
+ else
+ fmtprint(fmt, "0x%s", p);
+ else
+ fmtstrcpy(fmt, p);
free(p);
return 0;
}
--- /dev/null
+++ b/sys/src/libmp/port/mplogic.c
@@ -1,0 +1,194 @@
+#include "os.h"
+#include <mp.h>
+#include "dat.h"
+
+/*
+ mplogic calculates b1|b2 subject to the
+ following flag bits (fl)
+
+ bit 0: subtract 1 from b1
+ bit 1: invert b1
+ bit 2: subtract 1 from b2
+ bit 3: invert b2
+ bit 4: add 1 to output
+ bit 5: invert output
+
+ it inverts appropriate bits automatically
+ depending on the signs of the inputs
+*/
+
+static void
+mplogic(mpint *b1, mpint *b2, mpint *sum, int fl)
+{+ mpint *t;
+ mpdigit *dp1, *dp2, *dpo, d1, d2, d;
+ int c1, c2, co;
+ int i;
+
+ assert(((b1->flags | b2->flags | sum->flags) & MPtimesafe) == 0);
+ if(b1->sign < 0) fl ^= 0x03;
+ if(b2->sign < 0) fl ^= 0x0c;
+ sum->sign = (int)(((fl|fl>>2)^fl>>4)<<30)>>31|1;
+ if(sum->sign < 0) fl ^= 0x30;
+ if(b2->top > b1->top){+ t = b1;
+ b1 = b2;
+ b2 = t;
+ fl = fl >> 2 & 0x03 | fl << 2 & 0x0c | fl & 0x30;
+ }
+ mpbits(sum, b1->top*Dbits);
+ dp1 = b1->p;
+ dp2 = b2->p;
+ dpo = sum->p;
+ c1 = fl & 1;
+ c2 = fl >> 2 & 1;
+ co = fl >> 4 & 1;
+ for(i = 0; i < b1->top; i++){+ d1 = dp1[i] - c1;
+ if(i < b2->top)
+ d2 = dp2[i] - c2;
+ else
+ d2 = 0;
+ if(d1 != (mpdigit)-1) c1 = 0;
+ if(d2 != (mpdigit)-1) c2 = 0;
+ if((fl & 2) != 0) d1 ^= -1;
+ if((fl & 8) != 0) d2 ^= -1;
+ d = d1 | d2;
+ if((fl & 32) != 0) d ^= -1;
+ d += co;
+ if(d != 0) co = 0;
+ dpo[i] = d;
+ }
+ sum->top = i;
+ mpnorm(sum);
+}
+
+void
+mpor(mpint *b1, mpint *b2, mpint *sum)
+{+ mplogic(b1, b2, sum, 0);
+}
+
+void
+mpand(mpint *b1, mpint *b2, mpint *sum)
+{+ mplogic(b1, b2, sum, 0x2a);
+}
+
+void
+mpbic(mpint *b1, mpint *b2, mpint *sum)
+{+ mplogic(b1, b2, sum, 0x22);
+}
+
+void
+mpnot(mpint *b, mpint *r)
+{+ mpadd(b, mpone, r);
+ r->sign ^= -2;
+}
+
+void
+mpxor(mpint *b1, mpint *b2, mpint *sum)
+{+ mpint *t;
+ mpdigit *dp1, *dp2, *dpo, d1, d2, d;
+ int c1, c2, co;
+ int i, fl;
+
+ assert(((b1->flags | b2->flags | sum->flags) & MPtimesafe) == 0);
+ if(b2->top > b1->top){+ t = b1;
+ b1 = b2;
+ b2 = t;
+ }
+ fl = (b1->sign & 10) ^ (b2->sign & 12);
+ sum->sign = (int)(fl << 28) >> 31;
+ mpbits(sum, b1->top*Dbits);
+ dp1 = b1->p;
+ dp2 = b2->p;
+ dpo = sum->p;
+ c1 = fl >> 1 & 1;
+ c2 = fl >> 2 & 1;
+ co = fl >> 3 & 1;
+ for(i = 0; i < b1->top; i++){+ d1 = dp1[i] - c1;
+ if(i < b2->top)
+ d2 = dp2[i] - c2;
+ else
+ d2 = 0;
+ if(d1 != (mpdigit)-1) c1 = 0;
+ if(d2 != (mpdigit)-1) c2 = 0;
+ d = d1 ^ d2;
+ d += co;
+ if(d != 0) co = 0;
+ dpo[i] = d;
+ }
+ sum->top = i;
+ mpnorm(sum);
+}
+
+void
+mptrunc(mpint *b, int n, mpint *r)
+{+ int d, m, i, c;
+
+ assert(((b->flags | r->flags) & MPtimesafe) == 0);
+ mpbits(r, n);
+ r->top = DIGITS(n);
+ d = n / Dbits;
+ m = n % Dbits;
+ r->sign = 1;
+ if(b->sign == -1){+ c = 1;
+ for(i = 0; i <= r->top; i++){+ if(i < b->top)
+ r->p[i] = ~(b->p[i] - c);
+ else
+ r->p[i] = -1;
+ if(r->p[i] != 0)
+ c = 0;
+ }
+ if(m != 0)
+ r->p[d] &= (1<<m) - 1;
+ }else if(b->sign == 1){+ if(d >= b->top){+ mpassign(b, r);
+ return;
+ }
+ if(b != r)
+ for(i = 0; i < d; i++)
+ r->p[i] = b->p[i];
+ if(m != 0)
+ r->p[d] = b->p[d] & (1<<m)-1;
+ }
+ mpnorm(r);
+}
+
+void
+mpxtend(mpint *b, int n, mpint *r)
+{+ int d, m, c, i;
+
+ d = (n - 1) / Dbits;
+ m = (n - 1) % Dbits;
+ if(d >= b->top){+ mpassign(b, r);
+ return;
+ }
+ mptrunc(b, n, r);
+ mpbits(r, n);
+ if((r->p[d] & 1<<m) == 0){+ mpnorm(r);
+ return;
+ }
+ r->p[d] |= -(1<<m);
+ r->sign = -1;
+ c = 1;
+ for(i = 0; i < r->top; i++){+ r->p[i] = ~(r->p[i] - c);
+ if(r->p[i] != 0)
+ c = 0;
+ }
+ mpnorm(r);
+}