root/src/cmd/gc/bits.c

DEFINITIONS

1. bany
2. bnum
3. blsh
4. bitno
5. Qconv

// Inferno utils/cc/bits.c
// http://code.google.com/p/inferno-os/source/browse/utils/cc/bits.c
//
//      Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
//      Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
//      Portions Copyright © 1997-1999 Vita Nuova Limited
//      Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
//      Portions Copyright © 2004,2006 Bruce Ellis
//      Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
//      Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
//      Portions Copyright © 2009 The Go Authors.  All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#include <u.h>
#include <libc.h>
#include "go.h"

/*
Bits
bor(Bits a, Bits b)
{
        Bits c;
        int i;

        for(i=0; i<BITS; i++)
                c.b[i] = a.b[i] | b.b[i];
        return c;
}

Bits
band(Bits a, Bits b)
{
        Bits c;
        int i;

        for(i=0; i<BITS; i++)
                c.b[i] = a.b[i] & b.b[i];
        return c;
}

Bits
bnot(Bits a)
{
        Bits c;
        int i;

        for(i=0; i<BITS; i++)
                c.b[i] = ~a.b[i];
        return c;
}
*/

int
bany(Bits *a)
{
        int i;

        for(i=0; i<BITS; i++)
                if(a->b[i])
                        return 1;
        return 0;
}

/*
int
beq(Bits a, Bits b)
{
        int i;

        for(i=0; i<BITS; i++)
                if(a.b[i] != b.b[i])
                        return 0;
        return 1;
}
*/

int
bnum(Bits a)
{
        int i;
        int32 b;

        for(i=0; i<BITS; i++)
                if(b = a.b[i])
                        return 32*i + bitno(b);
        fatal("bad in bnum");
        return 0;
}

Bits
blsh(uint n)
{
        Bits c;

        c = zbits;
        c.b[n/32] = 1L << (n%32);
        return c;
}

/*
int
bset(Bits a, uint n)
{
        if(a.b[n/32] & (1L << (n%32)))
                return 1;
        return 0;
}
*/

int
bitno(int32 b)
{
        int i;

        for(i=0; i<32; i++)
                if(b & (1L<<i))
                        return i;
        fatal("bad in bitno");
        return 0;
}

int
Qconv(Fmt *fp)
{
        Bits bits;
        int i, first;

        first = 1;
        bits = va_arg(fp->args, Bits);
        while(bany(&bits)) {
                i = bnum(bits);
                if(first)
                        first = 0;
                else
                        fmtprint(fp, " ");
                if(var[i].node == N || var[i].node->sym == S)
                        fmtprint(fp, "$%d", i);
                else {
                        fmtprint(fp, "%s(%d)", var[i].node->sym->name, i);
                        if(var[i].offset != 0)
                                fmtprint(fp, "%+lld", (vlong)var[i].offset);
                }
                bits.b[i/32] &= ~(1L << (i%32));
        }
        return 0;
}