mp: add logic operations; mpfmt: include 0x with #

sys/include/mp.h

@@ -76,6 +76,15 @@ void	mpmul(mpint *b1, mpint *b2, mpint *prod);	/* prod = b1*b2 */
 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 */

sys/src/libmp/port/mpfmt.c

@@ -146,7 +146,13 @@ mpfmt(Fmt *fmt)
 	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;
 	}

sys/src/libmp/port/mplogic.c

@@ -0,0 +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);
+}