dmisc.c File Reference

#include "gdtoaimp.h"

Include dependency graph for dmisc.c:

Go to the source code of this file.

Functions
char *	rv_alloc (int i)
char *	nrv_alloc (char *s, char **rve, int n)
void	freedtoa (char *s)
int	quorem (Bigint *b, Bigint *S)

Variables
char *	dtoa_result

Function Documentation

freedtoa()

void freedtoa

(

char *

s

)

Definition at line 99 of file dmisc.c.

{
    Bigint* b = (Bigint*)((void*)(s - sizeof(int*)));
    b->maxwds = 1 << (b->k = *(int*)b);
    Bfree(b);
#ifndef MULTIPLE_THREADS
    if(s == dtoa_result)
    {
        dtoa_result = 0;
    }
#endif
}

References Bfree(), dtoa_result, Bigint::k, and Bigint::maxwds.

Referenced by dtoa(), g__fmt(), and gdtoa().

nrv_alloc()

char* nrv_alloc	(	char *	s,
		char **	rve,
		int	n
	)

Definition at line 68 of file dmisc.c.

{
    char *rv, *t;

    t = rv = rv_alloc(n);
    while((*t = *s++) != 0)
    {
        {
            t++;
        }
    }
    if(rve)
    {
        {
            *rve = t;
        }
    }
    return rv;
}

References rv_alloc().

Referenced by dtoa(), and gdtoa().

quorem()

int quorem	(	Bigint *	b,
		Bigint *	S
	)

Definition at line 118 of file dmisc.c.

{
    int n;
    ULong *bx, *bxe, q, *sx, *sxe;
#ifdef ULLong
    ULLong borrow, carry, y, ys;
#else
    ULong borrow, carry, y, ys;
#ifdef Pack_32
    ULong si, z, zs;
#endif
#endif

    n = S->wds;
#ifdef DEBUG
    /*debug*/ if(b->wds > n)
        /*debug*/ Bug("oversize b in quorem");
#endif
    if(b->wds < n)
    {
        {
            return 0;
        }
    }
    sx = S->x;
    sxe = sx + --n;
    bx = b->x;
    bxe = bx + n;
    q = *bxe / (*sxe + 1); /* ensure q <= true quotient */
#ifdef DEBUG
    /*debug*/ if(q > 9)
        /*debug*/ Bug("oversized quotient in quorem");
#endif
    if(q)
    {
        borrow = 0;
        carry = 0;
        do
        {
#ifdef ULLong
            ys = *sx++ * (ULLong)q + carry;
            carry = ys >> 32;
            y = *bx - (ys & 0xffffffffUL) - borrow;
            borrow = y >> 32 & 1UL;
            *bx++ = y & 0xffffffffUL;
#else
#ifdef Pack_32
            si = *sx++;
            ys = (si & 0xffff) * q + carry;
            zs = (si >> 16) * q + (ys >> 16);
            carry = zs >> 16;
            y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
            borrow = (y & 0x10000) >> 16;
            z = (*bx >> 16) - (zs & 0xffff) - borrow;
            borrow = (z & 0x10000) >> 16;
            Storeinc(bx, z, y);
#else
            ys = *sx++ * q + carry;
            carry = ys >> 16;
            y = *bx - (ys & 0xffff) - borrow;
            borrow = (y & 0x10000) >> 16;
            *bx++ = y & 0xffff;
#endif
#endif
        } while(sx <= sxe);
        if(!*bxe)
        {
            bx = b->x;
            while(--bxe > bx && !*bxe)
            {
                --n;
            }
            b->wds = n;
        }
    }
    if(cmp(b, S) >= 0)
    {
        q++;
        borrow = 0;
        carry = 0;
        bx = b->x;
        sx = S->x;
        do
        {
#ifdef ULLong
            ys = *sx++ + carry;
            carry = ys >> 32;
            y = *bx - (ys & 0xffffffffUL) - borrow;
            borrow = y >> 32 & 1UL;
            *bx++ = y & 0xffffffffUL;
#else
#ifdef Pack_32
            si = *sx++;
            ys = (si & 0xffff) + carry;
            zs = (si >> 16) + (ys >> 16);
            carry = zs >> 16;
            y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
            borrow = (y & 0x10000) >> 16;
            z = (*bx >> 16) - (zs & 0xffff) - borrow;
            borrow = (z & 0x10000) >> 16;
            Storeinc(bx, z, y);
#else
            ys = *sx++ + carry;
            carry = ys >> 16;
            y = *bx - (ys & 0xffff) - borrow;
            borrow = (y & 0x10000) >> 16;
            *bx++ = y & 0xffff;
#endif
#endif
        } while(sx <= sxe);
        bx = b->x;
        bxe = bx + n;
        if(!*bxe)
        {
            while(--bxe > bx && !*bxe)
            {
                --n;
            }
            b->wds = n;
        }
    }

    // TODO: why is an int being returned?
    return (int)q;
}

References cmp(), Storeinc, UL, ULLong, Bigint::wds, and Bigint::x.

Referenced by dtoa(), and gdtoa().

rv_alloc()

char* rv_alloc

(

int

i

)

Definition at line 42 of file dmisc.c.

{
    int k, *r;
    size_t j;

    j = sizeof(ULong);
    for(k = 0; sizeof(Bigint) - sizeof(ULong) - sizeof(int) + j <= (size_t)i; j <<= 1)
    {
        k++;
    }
    r = (int*)Balloc(k);
    *r = k;
    return
#ifndef MULTIPLE_THREADS
        dtoa_result =
#endif
            (char*)(r + 1);
}

References Balloc(), and dtoa_result.

Referenced by dtoa(), gdtoa(), and nrv_alloc().

Variable Documentation

dtoa_result

char* dtoa_result

Definition at line 35 of file dmisc.c.

Referenced by freedtoa(), and rv_alloc().