X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=libgcc%2Fconfig%2Flibbid%2Fbid64_next.c;fp=libgcc%2Fconfig%2Flibbid%2Fbid64_next.c;h=00f1c79e72e53d5022bf7dfd41557fd1c7d19071;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/libgcc/config/libbid/bid64_next.c b/libgcc/config/libbid/bid64_next.c new file mode 100644 index 00000000..00f1c79e --- /dev/null +++ b/libgcc/config/libbid/bid64_next.c @@ -0,0 +1,481 @@ +/* Copyright (C) 2007, 2009 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +Under Section 7 of GPL version 3, you are granted additional +permissions described in the GCC Runtime Library Exception, version +3.1, as published by the Free Software Foundation. + +You should have received a copy of the GNU General Public License and +a copy of the GCC Runtime Library Exception along with this program; +see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +. */ + +#include "bid_internal.h" + +/***************************************************************************** + * BID64 nextup + ****************************************************************************/ + +#if DECIMAL_CALL_BY_REFERENCE +void +bid64_nextup (UINT64 * pres, + UINT64 * + px _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { + UINT64 x = *px; +#else +UINT64 +bid64_nextup (UINT64 x _EXC_FLAGS_PARAM _EXC_MASKS_PARAM + _EXC_INFO_PARAM) { +#endif + + UINT64 res; + UINT64 x_sign; + UINT64 x_exp; + BID_UI64DOUBLE tmp1; + int x_nr_bits; + int q1, ind; + UINT64 C1; // C1 represents x_signif (UINT64) + + // check for NaNs and infinities + if ((x & MASK_NAN) == MASK_NAN) { // check for NaN + if ((x & 0x0003ffffffffffffull) > 999999999999999ull) + x = x & 0xfe00000000000000ull; // clear G6-G12 and the payload bits + else + x = x & 0xfe03ffffffffffffull; // clear G6-G12 + if ((x & MASK_SNAN) == MASK_SNAN) { // SNaN + // set invalid flag + *pfpsf |= INVALID_EXCEPTION; + // return quiet (SNaN) + res = x & 0xfdffffffffffffffull; + } else { // QNaN + res = x; + } + BID_RETURN (res); + } else if ((x & MASK_INF) == MASK_INF) { // check for Infinity + if (!(x & 0x8000000000000000ull)) { // x is +inf + res = 0x7800000000000000ull; + } else { // x is -inf + res = 0xf7fb86f26fc0ffffull; // -MAXFP = -999...99 * 10^emax + } + BID_RETURN (res); + } + // unpack the argument + x_sign = x & MASK_SIGN; // 0 for positive, MASK_SIGN for negative + // if steering bits are 11 (condition will be 0), then exponent is G[0:w+1] => + if ((x & MASK_STEERING_BITS) == MASK_STEERING_BITS) { + x_exp = (x & MASK_BINARY_EXPONENT2) >> 51; // biased + C1 = (x & MASK_BINARY_SIG2) | MASK_BINARY_OR2; + if (C1 > 9999999999999999ull) { // non-canonical + x_exp = 0; + C1 = 0; + } + } else { + x_exp = (x & MASK_BINARY_EXPONENT1) >> 53; // biased + C1 = x & MASK_BINARY_SIG1; + } + + // check for zeros (possibly from non-canonical values) + if (C1 == 0x0ull) { + // x is 0 + res = 0x0000000000000001ull; // MINFP = 1 * 10^emin + } else { // x is not special and is not zero + if (x == 0x77fb86f26fc0ffffull) { + // x = +MAXFP = 999...99 * 10^emax + res = 0x7800000000000000ull; // +inf + } else if (x == 0x8000000000000001ull) { + // x = -MINFP = 1...99 * 10^emin + res = 0x8000000000000000ull; // -0 + } else { // -MAXFP <= x <= -MINFP - 1 ulp OR MINFP <= x <= MAXFP - 1 ulp + // can add/subtract 1 ulp to the significand + + // Note: we could check here if x >= 10^16 to speed up the case q1 =16 + // q1 = nr. of decimal digits in x (1 <= q1 <= 54) + // determine first the nr. of bits in x + if (C1 >= MASK_BINARY_OR2) { // x >= 2^53 + // split the 64-bit value in two 32-bit halves to avoid rounding errors + if (C1 >= 0x0000000100000000ull) { // x >= 2^32 + tmp1.d = (double) (C1 >> 32); // exact conversion + x_nr_bits = + 33 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } else { // x < 2^32 + tmp1.d = (double) C1; // exact conversion + x_nr_bits = + 1 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } + } else { // if x < 2^53 + tmp1.d = (double) C1; // exact conversion + x_nr_bits = + 1 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } + q1 = nr_digits[x_nr_bits - 1].digits; + if (q1 == 0) { + q1 = nr_digits[x_nr_bits - 1].digits1; + if (C1 >= nr_digits[x_nr_bits - 1].threshold_lo) + q1++; + } + // if q1 < P16 then pad the significand with zeros + if (q1 < P16) { + if (x_exp > (UINT64) (P16 - q1)) { + ind = P16 - q1; // 1 <= ind <= P16 - 1 + // pad with P16 - q1 zeros, until exponent = emin + // C1 = C1 * 10^ind + C1 = C1 * ten2k64[ind]; + x_exp = x_exp - ind; + } else { // pad with zeros until the exponent reaches emin + ind = x_exp; + C1 = C1 * ten2k64[ind]; + x_exp = EXP_MIN; + } + } + if (!x_sign) { // x > 0 + // add 1 ulp (add 1 to the significand) + C1++; + if (C1 == 0x002386f26fc10000ull) { // if C1 = 10^16 + C1 = 0x00038d7ea4c68000ull; // C1 = 10^15 + x_exp++; + } + // Ok, because MAXFP = 999...99 * 10^emax was caught already + } else { // x < 0 + // subtract 1 ulp (subtract 1 from the significand) + C1--; + if (C1 == 0x00038d7ea4c67fffull && x_exp != 0) { // if C1 = 10^15 - 1 + C1 = 0x002386f26fc0ffffull; // C1 = 10^16 - 1 + x_exp--; + } + } + // assemble the result + // if significand has 54 bits + if (C1 & MASK_BINARY_OR2) { + res = + x_sign | (x_exp << 51) | MASK_STEERING_BITS | (C1 & + MASK_BINARY_SIG2); + } else { // significand fits in 53 bits + res = x_sign | (x_exp << 53) | C1; + } + } // end -MAXFP <= x <= -MINFP - 1 ulp OR MINFP <= x <= MAXFP - 1 ulp + } // end x is not special and is not zero + BID_RETURN (res); +} + +/***************************************************************************** + * BID64 nextdown + ****************************************************************************/ + +#if DECIMAL_CALL_BY_REFERENCE +void +bid64_nextdown (UINT64 * pres, + UINT64 * + px _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { + UINT64 x = *px; +#else +UINT64 +bid64_nextdown (UINT64 x _EXC_FLAGS_PARAM _EXC_MASKS_PARAM + _EXC_INFO_PARAM) { +#endif + + UINT64 res; + UINT64 x_sign; + UINT64 x_exp; + BID_UI64DOUBLE tmp1; + int x_nr_bits; + int q1, ind; + UINT64 C1; // C1 represents x_signif (UINT64) + + // check for NaNs and infinities + if ((x & MASK_NAN) == MASK_NAN) { // check for NaN + if ((x & 0x0003ffffffffffffull) > 999999999999999ull) + x = x & 0xfe00000000000000ull; // clear G6-G12 and the payload bits + else + x = x & 0xfe03ffffffffffffull; // clear G6-G12 + if ((x & MASK_SNAN) == MASK_SNAN) { // SNaN + // set invalid flag + *pfpsf |= INVALID_EXCEPTION; + // return quiet (SNaN) + res = x & 0xfdffffffffffffffull; + } else { // QNaN + res = x; + } + BID_RETURN (res); + } else if ((x & MASK_INF) == MASK_INF) { // check for Infinity + if (x & 0x8000000000000000ull) { // x is -inf + res = 0xf800000000000000ull; + } else { // x is +inf + res = 0x77fb86f26fc0ffffull; // +MAXFP = +999...99 * 10^emax + } + BID_RETURN (res); + } + // unpack the argument + x_sign = x & MASK_SIGN; // 0 for positive, MASK_SIGN for negative + // if steering bits are 11 (condition will be 0), then exponent is G[0:w+1] => + if ((x & MASK_STEERING_BITS) == MASK_STEERING_BITS) { + x_exp = (x & MASK_BINARY_EXPONENT2) >> 51; // biased + C1 = (x & MASK_BINARY_SIG2) | MASK_BINARY_OR2; + if (C1 > 9999999999999999ull) { // non-canonical + x_exp = 0; + C1 = 0; + } + } else { + x_exp = (x & MASK_BINARY_EXPONENT1) >> 53; // biased + C1 = x & MASK_BINARY_SIG1; + } + + // check for zeros (possibly from non-canonical values) + if (C1 == 0x0ull) { + // x is 0 + res = 0x8000000000000001ull; // -MINFP = -1 * 10^emin + } else { // x is not special and is not zero + if (x == 0xf7fb86f26fc0ffffull) { + // x = -MAXFP = -999...99 * 10^emax + res = 0xf800000000000000ull; // -inf + } else if (x == 0x0000000000000001ull) { + // x = +MINFP = 1...99 * 10^emin + res = 0x0000000000000000ull; // -0 + } else { // -MAXFP + 1ulp <= x <= -MINFP OR MINFP + 1 ulp <= x <= MAXFP + // can add/subtract 1 ulp to the significand + + // Note: we could check here if x >= 10^16 to speed up the case q1 =16 + // q1 = nr. of decimal digits in x (1 <= q1 <= 16) + // determine first the nr. of bits in x + if (C1 >= 0x0020000000000000ull) { // x >= 2^53 + // split the 64-bit value in two 32-bit halves to avoid + // rounding errors + if (C1 >= 0x0000000100000000ull) { // x >= 2^32 + tmp1.d = (double) (C1 >> 32); // exact conversion + x_nr_bits = + 33 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } else { // x < 2^32 + tmp1.d = (double) C1; // exact conversion + x_nr_bits = + 1 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } + } else { // if x < 2^53 + tmp1.d = (double) C1; // exact conversion + x_nr_bits = + 1 + ((((unsigned int) (tmp1.ui64 >> 52)) & 0x7ff) - 0x3ff); + } + q1 = nr_digits[x_nr_bits - 1].digits; + if (q1 == 0) { + q1 = nr_digits[x_nr_bits - 1].digits1; + if (C1 >= nr_digits[x_nr_bits - 1].threshold_lo) + q1++; + } + // if q1 < P16 then pad the significand with zeros + if (q1 < P16) { + if (x_exp > (UINT64) (P16 - q1)) { + ind = P16 - q1; // 1 <= ind <= P16 - 1 + // pad with P16 - q1 zeros, until exponent = emin + // C1 = C1 * 10^ind + C1 = C1 * ten2k64[ind]; + x_exp = x_exp - ind; + } else { // pad with zeros until the exponent reaches emin + ind = x_exp; + C1 = C1 * ten2k64[ind]; + x_exp = EXP_MIN; + } + } + if (x_sign) { // x < 0 + // add 1 ulp (add 1 to the significand) + C1++; + if (C1 == 0x002386f26fc10000ull) { // if C1 = 10^16 + C1 = 0x00038d7ea4c68000ull; // C1 = 10^15 + x_exp++; + // Ok, because -MAXFP = -999...99 * 10^emax was caught already + } + } else { // x > 0 + // subtract 1 ulp (subtract 1 from the significand) + C1--; + if (C1 == 0x00038d7ea4c67fffull && x_exp != 0) { // if C1 = 10^15 - 1 + C1 = 0x002386f26fc0ffffull; // C1 = 10^16 - 1 + x_exp--; + } + } + // assemble the result + // if significand has 54 bits + if (C1 & MASK_BINARY_OR2) { + res = + x_sign | (x_exp << 51) | MASK_STEERING_BITS | (C1 & + MASK_BINARY_SIG2); + } else { // significand fits in 53 bits + res = x_sign | (x_exp << 53) | C1; + } + } // end -MAXFP <= x <= -MINFP - 1 ulp OR MINFP <= x <= MAXFP - 1 ulp + } // end x is not special and is not zero + BID_RETURN (res); +} + +/***************************************************************************** + * BID64 nextafter + ****************************************************************************/ + +#if DECIMAL_CALL_BY_REFERENCE +void +bid64_nextafter (UINT64 * pres, UINT64 * px, + UINT64 * + py _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { + UINT64 x = *px; + UINT64 y = *py; +#else +UINT64 +bid64_nextafter (UINT64 x, + UINT64 y _EXC_FLAGS_PARAM _EXC_MASKS_PARAM + _EXC_INFO_PARAM) { +#endif + + UINT64 res; + UINT64 tmp1, tmp2; + FPSC tmp_fpsf = 0; // dummy fpsf for calls to comparison functions + int res1, res2; + + // check for NaNs or infinities + if (((x & MASK_SPECIAL) == MASK_SPECIAL) || + ((y & MASK_SPECIAL) == MASK_SPECIAL)) { + // x is NaN or infinity or y is NaN or infinity + + if ((x & MASK_NAN) == MASK_NAN) { // x is NAN + if ((x & 0x0003ffffffffffffull) > 999999999999999ull) + x = x & 0xfe00000000000000ull; // clear G6-G12 and the payload bits + else + x = x & 0xfe03ffffffffffffull; // clear G6-G12 + if ((x & MASK_SNAN) == MASK_SNAN) { // x is SNAN + // set invalid flag + *pfpsf |= INVALID_EXCEPTION; + // return quiet (x) + res = x & 0xfdffffffffffffffull; + } else { // x is QNaN + if ((y & MASK_SNAN) == MASK_SNAN) { // y is SNAN + // set invalid flag + *pfpsf |= INVALID_EXCEPTION; + } + // return x + res = x; + } + BID_RETURN (res); + } else if ((y & MASK_NAN) == MASK_NAN) { // y is NAN + if ((y & 0x0003ffffffffffffull) > 999999999999999ull) + y = y & 0xfe00000000000000ull; // clear G6-G12 and the payload bits + else + y = y & 0xfe03ffffffffffffull; // clear G6-G12 + if ((y & MASK_SNAN) == MASK_SNAN) { // y is SNAN + // set invalid flag + *pfpsf |= INVALID_EXCEPTION; + // return quiet (y) + res = y & 0xfdffffffffffffffull; + } else { // y is QNaN + // return y + res = y; + } + BID_RETURN (res); + } else { // at least one is infinity + if ((x & MASK_ANY_INF) == MASK_INF) { // x = inf + x = x & (MASK_SIGN | MASK_INF); + } + if ((y & MASK_ANY_INF) == MASK_INF) { // y = inf + y = y & (MASK_SIGN | MASK_INF); + } + } + } + // neither x nor y is NaN + + // if not infinity, check for non-canonical values x (treated as zero) + if ((x & MASK_ANY_INF) != MASK_INF) { // x != inf + // unpack x + if ((x & MASK_STEERING_BITS) == MASK_STEERING_BITS) { + // if the steering bits are 11 (condition will be 0), then + // the exponent is G[0:w+1] + if (((x & MASK_BINARY_SIG2) | MASK_BINARY_OR2) > + 9999999999999999ull) { + // non-canonical + x = (x & MASK_SIGN) | ((x & MASK_BINARY_EXPONENT2) << 2); + } + } else { // if ((x & MASK_STEERING_BITS) != MASK_STEERING_BITS) x is unch. + ; // canonical + } + } + // no need to check for non-canonical y + + // neither x nor y is NaN + tmp_fpsf = *pfpsf; // save fpsf +#if DECIMAL_CALL_BY_REFERENCE + bid64_quiet_equal (&res1, px, + py _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); + bid64_quiet_greater (&res2, px, + py _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#else + res1 = + bid64_quiet_equal (x, + y _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); + res2 = + bid64_quiet_greater (x, + y _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#endif + *pfpsf = tmp_fpsf; // restore fpsf + if (res1) { // x = y + // return x with the sign of y + res = (y & 0x8000000000000000ull) | (x & 0x7fffffffffffffffull); + } else if (res2) { // x > y +#if DECIMAL_CALL_BY_REFERENCE + bid64_nextdown (&res, + px _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#else + res = + bid64_nextdown (x _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#endif + } else { // x < y +#if DECIMAL_CALL_BY_REFERENCE + bid64_nextup (&res, px _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#else + res = bid64_nextup (x _EXC_FLAGS_ARG _EXC_MASKS_ARG _EXC_INFO_ARG); +#endif + } + // if the operand x is finite but the result is infinite, signal + // overflow and inexact + if (((x & MASK_INF) != MASK_INF) && ((res & MASK_INF) == MASK_INF)) { + // set the inexact flag + *pfpsf |= INEXACT_EXCEPTION; + // set the overflow flag + *pfpsf |= OVERFLOW_EXCEPTION; + } + // if the result is in (-10^emin, 10^emin), and is different from the + // operand x, signal underflow and inexact + tmp1 = 0x00038d7ea4c68000ull; // +100...0[16] * 10^emin + tmp2 = res & 0x7fffffffffffffffull; + tmp_fpsf = *pfpsf; // save fpsf +#if DECIMAL_CALL_BY_REFERENCE + bid64_quiet_greater (&res1, &tmp1, + &tmp2 _EXC_FLAGS_ARG _EXC_MASKS_ARG + _EXC_INFO_ARG); + bid64_quiet_not_equal (&res2, &x, + &res _EXC_FLAGS_ARG _EXC_MASKS_ARG + _EXC_INFO_ARG); +#else + res1 = + bid64_quiet_greater (tmp1, + tmp2 _EXC_FLAGS_ARG _EXC_MASKS_ARG + _EXC_INFO_ARG); + res2 = + bid64_quiet_not_equal (x, + res _EXC_FLAGS_ARG _EXC_MASKS_ARG + _EXC_INFO_ARG); +#endif + *pfpsf = tmp_fpsf; // restore fpsf + if (res1 && res2) { + // if (bid64_quiet_greater (tmp1, tmp2, &tmp_fpsf) && + // bid64_quiet_not_equal (x, res, &tmp_fpsf)) { + // set the inexact flag + *pfpsf |= INEXACT_EXCEPTION; + // set the underflow flag + *pfpsf |= UNDERFLOW_EXCEPTION; + } + BID_RETURN (res); +}