86 lines
1.8 KiB
C
86 lines
1.8 KiB
C
#ifndef lint
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static char sccsid[] = "@(#)_base_il.c 1.1 94/10/31 SMI";
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#endif
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/*
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* Copyright (c) 1988 by Sun Microsystems, Inc.
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*/
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#include "base_conversion.h"
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/* The following should be coded as inline expansion templates. */
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/*
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* Fundamental utilities that multiply two shorts into a unsigned long, add
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* carry, compute quotient and remainder in underlying base, and return
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* quo<<16 | rem as a unsigned long.
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*/
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/*
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* C compilers tend to generate bad code - forcing full unsigned long by
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* unsigned long multiplies when what is really wanted is the unsigned long
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* product of half-long operands. Similarly the quotient and remainder are
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* all half-long. So these functions should really be implemented by inline
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* expansion templates.
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*/
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unsigned long
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_umac(x, y, c) /* p = x * y + c ; return p */
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_BIG_FLOAT_DIGIT x, y;
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unsigned long c;
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{
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return x * (unsigned long) y + c;
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}
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unsigned long
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_carry_in_b10000(x, c) /* p = x + c ; return (p/10000 << 16 |
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* p%10000) */
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_BIG_FLOAT_DIGIT x;
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long unsigned c;
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{
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unsigned long p = x + c ;
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return ((p / 10000) << 16) | (p % 10000);
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}
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void
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_carry_propagate_two(carry, psignificand)
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unsigned long carry;
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_BIG_FLOAT_DIGIT *psignificand;
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{
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/*
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* Propagate carries in a base-2**16 significand.
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*/
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long unsigned p;
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int j;
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j = 0;
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while (carry != 0) {
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p = _carry_in_b65536(psignificand[j],carry);
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psignificand[j++] = (_BIG_FLOAT_DIGIT) (p & 0xffff);
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carry = p >> 16;
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}
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}
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void
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_carry_propagate_ten(carry, psignificand)
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unsigned long carry;
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_BIG_FLOAT_DIGIT *psignificand;
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{
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/*
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* Propagate carries in a base-10**4 significand.
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*/
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int j;
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unsigned long p;
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j = 0;
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while (carry != 0) {
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p = _carry_in_b10000(psignificand[j],carry);
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psignificand[j++] = (_BIG_FLOAT_DIGIT) (p & 0xffff);
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carry = p >> 16;
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}
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}
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