/*************************************************************************** attotime.c Support functions for working with attotime data. **************************************************************************** Copyright Aaron Giles All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name 'MAME' nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ***************************************************************************/ #include "emucore.h" #include "eminline.h" #include "attotime.h" //************************************************************************** // GLOBAL VARIABLES //************************************************************************** const attotime attotime::zero(0, 0); const attotime attotime::never(ATTOTIME_MAX_SECONDS, 0); //************************************************************************** // CORE MATH FUNCTIONS //************************************************************************** //------------------------------------------------- // operator*= - multiply an attotime by a // constant //------------------------------------------------- attotime &attotime::operator*=(UINT32 factor) { // if one of the items is attotime::never, return attotime::never if (seconds >= ATTOTIME_MAX_SECONDS) return *this = never; // 0 times anything is zero if (factor == 0) return *this = zero; // split attoseconds into upper and lower halves which fit into 32 bits UINT32 attolo; UINT32 attohi = divu_64x32_rem(attoseconds, ATTOSECONDS_PER_SECOND_SQRT, &attolo); // scale the lower half, then split into high/low parts UINT64 temp = mulu_32x32(attolo, factor); UINT32 reslo; temp = divu_64x32_rem(temp, ATTOSECONDS_PER_SECOND_SQRT, &reslo); // scale the upper half, then split into high/low parts temp += mulu_32x32(attohi, factor); UINT32 reshi; temp = divu_64x32_rem(temp, ATTOSECONDS_PER_SECOND_SQRT, &reshi); // scale the seconds temp += mulu_32x32(seconds, factor); if (temp >= ATTOTIME_MAX_SECONDS) return *this = never; // build the result seconds = temp; attoseconds = (attoseconds_t)reslo + mul_32x32(reshi, ATTOSECONDS_PER_SECOND_SQRT); return *this; } //------------------------------------------------- // operator/= - divide an attotime by a constant //------------------------------------------------- attotime &attotime::operator/=(UINT32 factor) { // if one of the items is attotime::never, return attotime::never if (seconds >= ATTOTIME_MAX_SECONDS) return *this = never; // ignore divide by zero if (factor == 0) return *this; // split attoseconds into upper and lower halves which fit into 32 bits UINT32 attolo; UINT32 attohi = divu_64x32_rem(attoseconds, ATTOSECONDS_PER_SECOND_SQRT, &attolo); // divide the seconds and get the remainder UINT32 remainder; seconds = divu_64x32_rem(seconds, factor, &remainder); // combine the upper half of attoseconds with the remainder and divide that UINT64 temp = (INT64)attohi + mulu_32x32(remainder, ATTOSECONDS_PER_SECOND_SQRT); UINT32 reshi = divu_64x32_rem(temp, factor, &remainder); // combine the lower half of attoseconds with the remainder and divide that temp = attolo + mulu_32x32(remainder, ATTOSECONDS_PER_SECOND_SQRT); UINT32 reslo = divu_64x32_rem(temp, factor, &remainder); // round based on the remainder attoseconds = (attoseconds_t)reslo + mulu_32x32(reshi, ATTOSECONDS_PER_SECOND_SQRT); if (remainder >= factor / 2) if (++attoseconds >= ATTOSECONDS_PER_SECOND) { attoseconds = 0; seconds++; } return *this; } //------------------------------------------------- // as_string - return a temporary printable // string describing an attotime //------------------------------------------------- const char *attotime::as_string(int precision) const { static char buffers[8][30]; static int nextbuf; char *buffer = &buffers[nextbuf++ % 8][0]; // special case: never if (*this == never) sprintf(buffer, "%-*s", precision, "(never)"); // case 1: we want no precision; seconds only else if (precision == 0) sprintf(buffer, "%d", seconds); // case 2: we want 9 or fewer digits of precision else if (precision <= 9) { UINT32 upper = attoseconds / ATTOSECONDS_PER_SECOND_SQRT; int temp = precision; while (temp < 9) { upper /= 10; temp++; } sprintf(buffer, "%d.%0*d", seconds, precision, upper); } // case 3: more than 9 digits of precision else { UINT32 lower; UINT32 upper = divu_64x32_rem(attoseconds, ATTOSECONDS_PER_SECOND_SQRT, &lower); int temp = precision; while (temp < 18) { lower /= 10; temp++; } sprintf(buffer, "%d.%09d%0*d", seconds, upper, precision - 9, lower); } return buffer; }