| /* Copyright (C) 2007-2017 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| #define BID_128RES |
| #include "bid_internal.h" |
| |
| /***************************************************************************** |
| * BID128 minimum number |
| *****************************************************************************/ |
| |
| #if DECIMAL_CALL_BY_REFERENCE |
| void |
| bid128_minnum (UINT128 * pres, UINT128 * px, |
| UINT128 * py _EXC_FLAGS_PARAM) { |
| UINT128 x = *px; |
| UINT128 y = *py; |
| #else |
| UINT128 |
| bid128_minnum (UINT128 x, UINT128 y _EXC_FLAGS_PARAM) { |
| #endif |
| |
| UINT128 res; |
| int exp_x, exp_y; |
| int diff; |
| UINT128 sig_x, sig_y; |
| UINT192 sig_n_prime192; |
| UINT256 sig_n_prime256; |
| char x_is_zero = 0, y_is_zero = 0; |
| |
| BID_SWAP128 (x); |
| BID_SWAP128 (y); |
| |
| // check for non-canonical x |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| x.w[1] = x.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((x.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((x.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (x.w[0] > 0x38c15b09ffffffffull))) { |
| x.w[1] = x.w[1] & 0xffffc00000000000ull; |
| x.w[0] = 0x0ull; |
| } |
| } else if ((x.w[1] & MASK_ANY_INF) == MASK_INF) { // x = inf |
| x.w[1] = x.w[1] & (MASK_SIGN | MASK_INF); |
| x.w[0] = 0x0ull; |
| } else { // x is not special |
| // check for non-canonical values - treated as zero |
| if ((x.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| x.w[1] = (x.w[1] & MASK_SIGN) | ((x.w[1] << 2) & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((x.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((x.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && x.w[0] > 0x378d8e63ffffffffull)) { |
| // x is non-canonical if coefficient is larger than 10^34 -1 |
| x.w[1] = (x.w[1] & MASK_SIGN) | (x.w[1] & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| // check for non-canonical y |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| y.w[1] = y.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((y.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((y.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (y.w[0] > 0x38c15b09ffffffffull))) { |
| y.w[1] = y.w[1] & 0xffffc00000000000ull; |
| y.w[0] = 0x0ull; |
| } |
| } else if ((y.w[1] & MASK_ANY_INF) == MASK_INF) { // y = inf |
| y.w[1] = y.w[1] & (MASK_SIGN | MASK_INF); |
| y.w[0] = 0x0ull; |
| } else { // y is not special |
| // check for non-canonical values - treated as zero |
| if ((y.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| y.w[1] = (y.w[1] & MASK_SIGN) | ((y.w[1] << 2) & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((y.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((y.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && y.w[0] > 0x378d8e63ffffffffull)) { |
| // y is non-canonical if coefficient is larger than 10^34 -1 |
| y.w[1] = (y.w[1] & MASK_SIGN) | (y.w[1] & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| |
| // NaN (CASE1) |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| if ((x.w[1] & MASK_SNAN) == MASK_SNAN) { // x is SNaN |
| // if x is SNAN, then return quiet (x) |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| x.w[1] = x.w[1] & 0xfdffffffffffffffull; // quietize x |
| res = x; |
| } else { // x is QNaN |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { // y is SNAN |
| *pfpsf |= INVALID_EXCEPTION; // set invalid flag |
| } |
| res = x; |
| } else { |
| res = y; |
| } |
| } |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NaN, but x is not |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| y.w[1] = y.w[1] & 0xfdffffffffffffffull; // quietize y |
| res = y; |
| } else { |
| // will return x (which is not NaN) |
| res = x; |
| } |
| BID_RETURN (res); |
| } |
| // SIMPLE (CASE2) |
| // if all the bits are the same, these numbers are equal (not Greater). |
| if (x.w[0] == y.w[0] && x.w[1] == y.w[1]) { |
| res = x; |
| BID_RETURN (res); |
| } |
| // INFINITY (CASE3) |
| if ((x.w[1] & MASK_INF) == MASK_INF) { |
| // if x is neg infinity, there is no way it is greater than y, return 0 |
| res = (((x.w[1] & MASK_SIGN) == MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_INF) == MASK_INF) { |
| // x is finite, so if y is positive infinity, then x is less, return 0 |
| // if y is negative infinity, then x is greater, return 1 |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| // CONVERT X |
| sig_x.w[1] = x.w[1] & 0x0001ffffffffffffull; |
| sig_x.w[0] = x.w[0]; |
| exp_x = (x.w[1] >> 49) & 0x000000000003fffull; |
| |
| // CONVERT Y |
| exp_y = (y.w[1] >> 49) & 0x0000000000003fffull; |
| sig_y.w[1] = y.w[1] & 0x0001ffffffffffffull; |
| sig_y.w[0] = y.w[0]; |
| |
| // ZERO (CASE4) |
| // some properties: |
| // (+ZERO == -ZERO) => therefore ignore the sign |
| // (ZERO x 10^A == ZERO x 10^B) for any valid A, B => ignore the exponent |
| // field |
| // (Any non-canonical # is considered 0) |
| if ((sig_x.w[1] == 0) && (sig_x.w[0] == 0)) { |
| x_is_zero = 1; |
| } |
| if ((sig_y.w[1] == 0) && (sig_y.w[0] == 0)) { |
| y_is_zero = 1; |
| } |
| |
| if (x_is_zero && y_is_zero) { |
| // if both numbers are zero, neither is greater => return either number |
| res = x; |
| BID_RETURN (res); |
| } else if (x_is_zero) { |
| // is x is zero, it is greater if Y is negative |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } else if (y_is_zero) { |
| // is y is zero, X is greater if it is positive |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| // OPPOSITE SIGN (CASE5) |
| // now, if the sign bits differ, x is greater if y is negative |
| if (((x.w[1] ^ y.w[1]) & MASK_SIGN) == MASK_SIGN) { |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| // REDUNDANT REPRESENTATIONS (CASE6) |
| // if exponents are the same, then we have a simple comparison of |
| // the significands |
| if (exp_y == exp_x) { |
| res = (((sig_x.w[1] > sig_y.w[1]) |
| || (sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] >= sig_y.w[0])) ^ ((x.w[1] & MASK_SIGN) == |
| MASK_SIGN)) ? y : x; |
| BID_RETURN (res); |
| } |
| // if both components are either bigger or smaller, it is clear what |
| // needs to be done |
| if (sig_x.w[1] >= sig_y.w[1] && sig_x.w[0] >= sig_y.w[0] |
| && exp_x > exp_y) { |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| if (sig_x.w[1] <= sig_y.w[1] && sig_x.w[0] <= sig_y.w[0] |
| && exp_x < exp_y) { |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| |
| diff = exp_x - exp_y; |
| |
| // if |exp_x - exp_y| < 33, it comes down to the compensated significand |
| if (diff > 0) { // to simplify the loop below, |
| // if exp_x is 33 greater than exp_y, no need for compensation |
| if (diff > 33) { |
| // difference cannot be greater than 10^33 |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| __mul_128x128_to_256 (sig_n_prime256, sig_x, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = ((((sig_n_prime256.w[3] > 0) || sig_n_prime256.w[2] > 0) |
| || (sig_n_prime256.w[1] > sig_y.w[1]) |
| || (sig_n_prime256.w[1] == sig_y.w[1] |
| && sig_n_prime256.w[0] > |
| sig_y.w[0])) ^ ((y.w[1] & MASK_SIGN) == |
| MASK_SIGN)) ? y : x; |
| BID_RETURN (res); |
| } |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_x); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = |
| (((sig_n_prime192.w[2] > 0) || (sig_n_prime192.w[1] > sig_y.w[1]) |
| || (sig_n_prime192.w[1] == sig_y.w[1] |
| && sig_n_prime192.w[0] > |
| sig_y.w[0])) ^ ((y.w[1] & MASK_SIGN) == MASK_SIGN)) ? y : x; |
| BID_RETURN (res); |
| } |
| diff = exp_y - exp_x; |
| // if exp_x is 33 less than exp_y, no need for compensation |
| if (diff > 33) { |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| // adjust the y significand upwards |
| __mul_128x128_to_256 (sig_n_prime256, sig_y, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = |
| ((sig_n_prime256.w[3] != 0 || sig_n_prime256.w[2] != 0 |
| || (sig_n_prime256.w[1] > sig_x.w[1] |
| || (sig_n_prime256.w[1] == sig_x.w[1] |
| && sig_n_prime256.w[0] > |
| sig_x.w[0]))) ^ ((x.w[1] & MASK_SIGN) == |
| MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| // adjust the y significand upwards |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_y); |
| // if postitive, return whichever significand is larger (converse if negative) |
| res = |
| ((sig_n_prime192.w[2] != 0 |
| || (sig_n_prime192.w[1] > sig_x.w[1] |
| || (sig_n_prime192.w[1] == sig_x.w[1] |
| && sig_n_prime192.w[0] > sig_x.w[0]))) |
| ^ ((y.w[1] & MASK_SIGN) == MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| |
| /***************************************************************************** |
| * BID128 minimum magnitude function - returns greater of two numbers |
| *****************************************************************************/ |
| |
| #if DECIMAL_CALL_BY_REFERENCE |
| void |
| bid128_minnum_mag (UINT128 * pres, UINT128 * px, |
| UINT128 * py _EXC_FLAGS_PARAM) { |
| UINT128 x = *px; |
| UINT128 y = *py; |
| #else |
| UINT128 |
| bid128_minnum_mag (UINT128 x, UINT128 y _EXC_FLAGS_PARAM) { |
| #endif |
| |
| UINT128 res; |
| int exp_x, exp_y; |
| int diff; |
| UINT128 sig_x, sig_y; |
| UINT192 sig_n_prime192; |
| UINT256 sig_n_prime256; |
| |
| BID_SWAP128 (x); |
| BID_SWAP128 (y); |
| |
| // check for non-canonical x |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| x.w[1] = x.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((x.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((x.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (x.w[0] > 0x38c15b09ffffffffull))) { |
| x.w[1] = x.w[1] & 0xffffc00000000000ull; |
| x.w[0] = 0x0ull; |
| } |
| } else if ((x.w[1] & MASK_ANY_INF) == MASK_INF) { // x = inf |
| x.w[1] = x.w[1] & (MASK_SIGN | MASK_INF); |
| x.w[0] = 0x0ull; |
| } else { // x is not special |
| // check for non-canonical values - treated as zero |
| if ((x.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| x.w[1] = (x.w[1] & MASK_SIGN) | ((x.w[1] << 2) & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((x.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((x.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && x.w[0] > 0x378d8e63ffffffffull)) { |
| // x is non-canonical if coefficient is larger than 10^34 -1 |
| x.w[1] = (x.w[1] & MASK_SIGN) | (x.w[1] & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| // check for non-canonical y |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| y.w[1] = y.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((y.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((y.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (y.w[0] > 0x38c15b09ffffffffull))) { |
| y.w[1] = y.w[1] & 0xffffc00000000000ull; |
| y.w[0] = 0x0ull; |
| } |
| } else if ((y.w[1] & MASK_ANY_INF) == MASK_INF) { // y = inf |
| y.w[1] = y.w[1] & (MASK_SIGN | MASK_INF); |
| y.w[0] = 0x0ull; |
| } else { // y is not special |
| // check for non-canonical values - treated as zero |
| if ((y.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| y.w[1] = (y.w[1] & MASK_SIGN) | ((y.w[1] << 2) & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((y.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((y.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && y.w[0] > 0x378d8e63ffffffffull)) { |
| // y is non-canonical if coefficient is larger than 10^34 -1 |
| y.w[1] = (y.w[1] & MASK_SIGN) | (y.w[1] & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| |
| // NaN (CASE1) |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| if ((x.w[1] & MASK_SNAN) == MASK_SNAN) { // x is SNaN |
| // if x is SNAN, then return quiet (x) |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| x.w[1] = x.w[1] & 0xfdffffffffffffffull; // quietize x |
| res = x; |
| } else { // x is QNaN |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { // y is SNAN |
| *pfpsf |= INVALID_EXCEPTION; // set invalid flag |
| } |
| res = x; |
| } else { |
| res = y; |
| } |
| } |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NaN, but x is not |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| y.w[1] = y.w[1] & 0xfdffffffffffffffull; // quietize y |
| res = y; |
| } else { |
| // will return x (which is not NaN) |
| res = x; |
| } |
| BID_RETURN (res); |
| } |
| // SIMPLE (CASE2) |
| // if all the bits are the same, these numbers are equal (not Greater). |
| if (x.w[0] == y.w[0] && x.w[1] == y.w[1]) { |
| res = y; |
| BID_RETURN (res); |
| } |
| // INFINITY (CASE3) |
| if ((x.w[1] & MASK_INF) == MASK_INF) { |
| // if x infinity, it has maximum magnitude. |
| // Check if magnitudes are equal. If x is negative, return it. |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN |
| && (y.w[1] & MASK_INF) == MASK_INF) ? x : y; |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_INF) == MASK_INF) { |
| // x is finite, so if y is infinity, then x is less in magnitude |
| res = x; |
| BID_RETURN (res); |
| } |
| // CONVERT X |
| sig_x.w[1] = x.w[1] & 0x0001ffffffffffffull; |
| sig_x.w[0] = x.w[0]; |
| exp_x = (x.w[1] >> 49) & 0x000000000003fffull; |
| |
| // CONVERT Y |
| exp_y = (y.w[1] >> 49) & 0x0000000000003fffull; |
| sig_y.w[1] = y.w[1] & 0x0001ffffffffffffull; |
| sig_y.w[0] = y.w[0]; |
| |
| // ZERO (CASE4) |
| // some properties: |
| // (+ZERO == -ZERO) => therefore ignore the sign |
| // (ZERO x 10^A == ZERO x 10^B) for any valid A, B => |
| // therefore ignore the exponent field |
| // (Any non-canonical # is considered 0) |
| if ((sig_x.w[1] == 0) && (sig_x.w[0] == 0)) { |
| res = x; |
| BID_RETURN (res); |
| } |
| if ((sig_y.w[1] == 0) && (sig_y.w[0] == 0)) { |
| res = y; |
| BID_RETURN (res); |
| } |
| // REDUNDANT REPRESENTATIONS (CASE6) |
| // check if exponents are the same and significands are the same |
| if (exp_y == exp_x && sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] == sig_y.w[0]) { |
| if (x.w[1] & 0x8000000000000000ull) { // x is negative |
| res = x; |
| BID_RETURN (res); |
| } else { |
| res = y; |
| BID_RETURN (res); |
| } |
| } else if (((sig_x.w[1] > sig_y.w[1] || (sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] > sig_y.w[0])) |
| && exp_x == exp_y) |
| || ((sig_x.w[1] > sig_y.w[1] |
| || (sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] >= sig_y.w[0])) |
| && exp_x > exp_y)) { |
| // if both components are either bigger or smaller, it is clear what |
| // needs to be done; also if the magnitudes are equal |
| res = y; |
| BID_RETURN (res); |
| } else if (((sig_y.w[1] > sig_x.w[1] || (sig_y.w[1] == sig_x.w[1] |
| && sig_y.w[0] > sig_x.w[0])) |
| && exp_y == exp_x) |
| || ((sig_y.w[1] > sig_x.w[1] |
| || (sig_y.w[1] == sig_x.w[1] |
| && sig_y.w[0] >= sig_x.w[0])) |
| && exp_y > exp_x)) { |
| res = x; |
| BID_RETURN (res); |
| } else { |
| ; // continue |
| } |
| diff = exp_x - exp_y; |
| // if |exp_x - exp_y| < 33, it comes down to the compensated significand |
| if (diff > 0) { // to simplify the loop below, |
| // if exp_x is 33 greater than exp_y, no need for compensation |
| if (diff > 33) { |
| res = y; // difference cannot be greater than 10^33 |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| __mul_128x128_to_256 (sig_n_prime256, sig_x, ten2k128[diff - 20]); |
| // if positive, return whichever significand is larger |
| // (converse if negative) |
| if (sig_n_prime256.w[3] == 0 && (sig_n_prime256.w[2] == 0) |
| && sig_n_prime256.w[1] == sig_y.w[1] |
| && (sig_n_prime256.w[0] == sig_y.w[0])) { |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; // if equal |
| BID_RETURN (res); |
| } |
| res = (((sig_n_prime256.w[3] > 0) || sig_n_prime256.w[2] > 0) |
| || (sig_n_prime256.w[1] > sig_y.w[1]) |
| || (sig_n_prime256.w[1] == sig_y.w[1] |
| && sig_n_prime256.w[0] > sig_y.w[0])) ? y : x; |
| BID_RETURN (res); |
| } |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_x); |
| // if positive, return whichever significand is larger |
| // (converse if negative) |
| if ((sig_n_prime192.w[2] == 0) && sig_n_prime192.w[1] == sig_y.w[1] |
| && (sig_n_prime192.w[0] == sig_y.w[0])) { |
| // if = in magnitude, return +, (if possible) |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| res = ((sig_n_prime192.w[2] > 0) |
| || (sig_n_prime192.w[1] > sig_y.w[1]) |
| || (sig_n_prime192.w[1] == sig_y.w[1] |
| && sig_n_prime192.w[0] > sig_y.w[0])) ? y : x; |
| BID_RETURN (res); |
| } |
| diff = exp_y - exp_x; |
| // if exp_x is 33 less than exp_y, no need for compensation |
| if (diff > 33) { |
| res = x; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| // adjust the y significand upwards |
| __mul_128x128_to_256 (sig_n_prime256, sig_y, ten2k128[diff - 20]); |
| // if positive, return whichever significand is larger |
| // (converse if negative) |
| if (sig_n_prime256.w[3] == 0 && (sig_n_prime256.w[2] == 0) |
| && sig_n_prime256.w[1] == sig_x.w[1] |
| && (sig_n_prime256.w[0] == sig_x.w[0])) { |
| // if = in magnitude, return +, (if possible) |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| res = (sig_n_prime256.w[3] == 0 && sig_n_prime256.w[2] == 0 |
| && (sig_n_prime256.w[1] < sig_x.w[1] |
| || (sig_n_prime256.w[1] == sig_x.w[1] |
| && sig_n_prime256.w[0] < sig_x.w[0]))) ? y : x; |
| BID_RETURN (res); |
| } |
| // adjust the y significand upwards |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_y); |
| // if positive, return whichever significand is larger (converse if negative) |
| if ((sig_n_prime192.w[2] == 0) && sig_n_prime192.w[1] == sig_x.w[1] |
| && (sig_n_prime192.w[0] == sig_x.w[0])) { |
| // if = in magnitude, return +, if possible) |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } |
| res = (sig_n_prime192.w[2] == 0 |
| && (sig_n_prime192.w[1] < sig_x.w[1] |
| || (sig_n_prime192.w[1] == sig_x.w[1] |
| && sig_n_prime192.w[0] < sig_x.w[0]))) ? y : x; |
| BID_RETURN (res); |
| } |
| |
| /***************************************************************************** |
| * BID128 maximum function - returns greater of two numbers |
| *****************************************************************************/ |
| |
| #if DECIMAL_CALL_BY_REFERENCE |
| void |
| bid128_maxnum (UINT128 * pres, UINT128 * px, |
| UINT128 * py _EXC_FLAGS_PARAM) { |
| UINT128 x = *px; |
| UINT128 y = *py; |
| #else |
| UINT128 |
| bid128_maxnum (UINT128 x, UINT128 y _EXC_FLAGS_PARAM) { |
| #endif |
| |
| UINT128 res; |
| int exp_x, exp_y; |
| int diff; |
| UINT128 sig_x, sig_y; |
| UINT192 sig_n_prime192; |
| UINT256 sig_n_prime256; |
| char x_is_zero = 0, y_is_zero = 0; |
| |
| BID_SWAP128 (x); |
| BID_SWAP128 (y); |
| |
| // check for non-canonical x |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| x.w[1] = x.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((x.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((x.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (x.w[0] > 0x38c15b09ffffffffull))) { |
| x.w[1] = x.w[1] & 0xffffc00000000000ull; |
| x.w[0] = 0x0ull; |
| } |
| } else if ((x.w[1] & MASK_ANY_INF) == MASK_INF) { // x = inf |
| x.w[1] = x.w[1] & (MASK_SIGN | MASK_INF); |
| x.w[0] = 0x0ull; |
| } else { // x is not special |
| // check for non-canonical values - treated as zero |
| if ((x.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| x.w[1] = (x.w[1] & MASK_SIGN) | ((x.w[1] << 2) & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((x.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((x.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && x.w[0] > 0x378d8e63ffffffffull)) { |
| // x is non-canonical if coefficient is larger than 10^34 -1 |
| x.w[1] = (x.w[1] & MASK_SIGN) | (x.w[1] & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| // check for non-canonical y |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| y.w[1] = y.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((y.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((y.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (y.w[0] > 0x38c15b09ffffffffull))) { |
| y.w[1] = y.w[1] & 0xffffc00000000000ull; |
| y.w[0] = 0x0ull; |
| } |
| } else if ((y.w[1] & MASK_ANY_INF) == MASK_INF) { // y = inf |
| y.w[1] = y.w[1] & (MASK_SIGN | MASK_INF); |
| y.w[0] = 0x0ull; |
| } else { // y is not special |
| // check for non-canonical values - treated as zero |
| if ((y.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| y.w[1] = (y.w[1] & MASK_SIGN) | ((y.w[1] << 2) & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((y.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((y.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && y.w[0] > 0x378d8e63ffffffffull)) { |
| // y is non-canonical if coefficient is larger than 10^34 -1 |
| y.w[1] = (y.w[1] & MASK_SIGN) | (y.w[1] & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| |
| // NaN (CASE1) |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| if ((x.w[1] & MASK_SNAN) == MASK_SNAN) { // x is SNaN |
| // if x is SNAN, then return quiet (x) |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| x.w[1] = x.w[1] & 0xfdffffffffffffffull; // quietize x |
| res = x; |
| } else { // x is QNaN |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { // y is SNAN |
| *pfpsf |= INVALID_EXCEPTION; // set invalid flag |
| } |
| res = x; |
| } else { |
| res = y; |
| } |
| } |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NaN, but x is not |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| y.w[1] = y.w[1] & 0xfdffffffffffffffull; // quietize y |
| res = y; |
| } else { |
| // will return x (which is not NaN) |
| res = x; |
| } |
| BID_RETURN (res); |
| } |
| // SIMPLE (CASE2) |
| // if all the bits are the same, these numbers are equal (not Greater). |
| if (x.w[0] == y.w[0] && x.w[1] == y.w[1]) { |
| res = x; |
| BID_RETURN (res); |
| } |
| // INFINITY (CASE3) |
| if ((x.w[1] & MASK_INF) == MASK_INF) { |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN) ? y : x; |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_INF) == MASK_INF) { |
| // x is finite, so if y is positive infinity, then x is less, return 0 |
| // if y is negative infinity, then x is greater, return 1 |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| // CONVERT X |
| sig_x.w[1] = x.w[1] & 0x0001ffffffffffffull; |
| sig_x.w[0] = x.w[0]; |
| exp_x = (x.w[1] >> 49) & 0x000000000003fffull; |
| |
| // CONVERT Y |
| exp_y = (y.w[1] >> 49) & 0x0000000000003fffull; |
| sig_y.w[1] = y.w[1] & 0x0001ffffffffffffull; |
| sig_y.w[0] = y.w[0]; |
| |
| // ZERO (CASE4) |
| // some properties: |
| // (+ZERO == -ZERO) => therefore ignore the sign |
| // (ZERO x 10^A == ZERO x 10^B) for any valid A, B => |
| // therefore ignore the exponent field |
| // (Any non-canonical # is considered 0) |
| if ((sig_x.w[1] == 0) && (sig_x.w[0] == 0)) { |
| x_is_zero = 1; |
| } |
| if ((sig_y.w[1] == 0) && (sig_y.w[0] == 0)) { |
| y_is_zero = 1; |
| } |
| |
| if (x_is_zero && y_is_zero) { |
| // if both numbers are zero, neither is greater => return either number |
| res = x; |
| BID_RETURN (res); |
| } else if (x_is_zero) { |
| // is x is zero, it is greater if Y is negative |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } else if (y_is_zero) { |
| // is y is zero, X is greater if it is positive |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| // OPPOSITE SIGN (CASE5) |
| // now, if the sign bits differ, x is greater if y is negative |
| if (((x.w[1] ^ y.w[1]) & MASK_SIGN) == MASK_SIGN) { |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| // REDUNDANT REPRESENTATIONS (CASE6) |
| // if exponents are the same, then we have a simple comparison of |
| // the significands |
| if (exp_y == exp_x) { |
| res = (((sig_x.w[1] > sig_y.w[1]) || (sig_x.w[1] == sig_y.w[1] && |
| sig_x.w[0] >= sig_y.w[0])) ^ |
| ((x.w[1] & MASK_SIGN) == MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| // if both components are either bigger or smaller, it is clear what |
| // needs to be done |
| if ((sig_x.w[1] > sig_y.w[1] |
| || (sig_x.w[1] == sig_y.w[1] && sig_x.w[0] > sig_y.w[0])) |
| && exp_x >= exp_y) { |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| if ((sig_x.w[1] < sig_y.w[1] |
| || (sig_x.w[1] == sig_y.w[1] && sig_x.w[0] < sig_y.w[0])) |
| && exp_x <= exp_y) { |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| diff = exp_x - exp_y; |
| // if |exp_x - exp_y| < 33, it comes down to the compensated significand |
| if (diff > 0) { // to simplify the loop below, |
| // if exp_x is 33 greater than exp_y, no need for compensation |
| if (diff > 33) { |
| // difference cannot be greater than 10^33 |
| res = ((x.w[1] & MASK_SIGN) != MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| __mul_128x128_to_256 (sig_n_prime256, sig_x, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = ((((sig_n_prime256.w[3] > 0) || sig_n_prime256.w[2] > 0) |
| || (sig_n_prime256.w[1] > sig_y.w[1]) |
| || (sig_n_prime256.w[1] == sig_y.w[1] |
| && sig_n_prime256.w[0] > |
| sig_y.w[0])) ^ ((y.w[1] & MASK_SIGN) == |
| MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_x); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = |
| (((sig_n_prime192.w[2] > 0) || (sig_n_prime192.w[1] > sig_y.w[1]) |
| || (sig_n_prime192.w[1] == sig_y.w[1] |
| && sig_n_prime192.w[0] > |
| sig_y.w[0])) ^ ((y.w[1] & MASK_SIGN) == MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| diff = exp_y - exp_x; |
| // if exp_x is 33 less than exp_y, no need for compensation |
| if (diff > 33) { |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| // adjust the y significand upwards |
| __mul_128x128_to_256 (sig_n_prime256, sig_y, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| res = |
| ((sig_n_prime256.w[3] != 0 || sig_n_prime256.w[2] != 0 |
| || (sig_n_prime256.w[1] > sig_x.w[1] |
| || (sig_n_prime256.w[1] == sig_x.w[1] |
| && sig_n_prime256.w[0] > |
| sig_x.w[0]))) ^ ((x.w[1] & MASK_SIGN) != |
| MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| // adjust the y significand upwards |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_y); |
| // if postitive, return whichever significand is larger (converse if negative) |
| res = |
| ((sig_n_prime192.w[2] != 0 |
| || (sig_n_prime192.w[1] > sig_x.w[1] |
| || (sig_n_prime192.w[1] == sig_x.w[1] |
| && sig_n_prime192.w[0] > |
| sig_x.w[0]))) ^ ((y.w[1] & MASK_SIGN) != |
| MASK_SIGN)) ? x : y; |
| BID_RETURN (res); |
| } |
| |
| /***************************************************************************** |
| * BID128 maximum magnitude function - returns greater of two numbers |
| *****************************************************************************/ |
| |
| #if DECIMAL_CALL_BY_REFERENCE |
| void |
| bid128_maxnum_mag (UINT128 * pres, UINT128 * px, |
| UINT128 * py _EXC_FLAGS_PARAM) { |
| UINT128 x = *px; |
| UINT128 y = *py; |
| #else |
| UINT128 |
| bid128_maxnum_mag (UINT128 x, UINT128 y _EXC_FLAGS_PARAM) { |
| #endif |
| |
| UINT128 res; |
| int exp_x, exp_y; |
| int diff; |
| UINT128 sig_x, sig_y; |
| UINT192 sig_n_prime192; |
| UINT256 sig_n_prime256; |
| |
| BID_SWAP128 (x); |
| BID_SWAP128 (y); |
| |
| // check for non-canonical x |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| x.w[1] = x.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((x.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((x.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (x.w[0] > 0x38c15b09ffffffffull))) { |
| x.w[1] = x.w[1] & 0xffffc00000000000ull; |
| x.w[0] = 0x0ull; |
| } |
| } else if ((x.w[1] & MASK_ANY_INF) == MASK_INF) { // x = inf |
| x.w[1] = x.w[1] & (MASK_SIGN | MASK_INF); |
| x.w[0] = 0x0ull; |
| } else { // x is not special |
| // check for non-canonical values - treated as zero |
| if ((x.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| x.w[1] = (x.w[1] & MASK_SIGN) | ((x.w[1] << 2) & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((x.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((x.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull |
| && x.w[0] > 0x378d8e63ffffffffull)) { |
| // x is non-canonical if coefficient is larger than 10^34 -1 |
| x.w[1] = (x.w[1] & MASK_SIGN) | (x.w[1] & MASK_EXP); |
| x.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| // check for non-canonical y |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| y.w[1] = y.w[1] & 0xfe003fffffffffffull; // clear out G[6]-G[16] |
| // check for non-canonical NaN payload |
| if (((y.w[1] & 0x00003fffffffffffull) > 0x0000314dc6448d93ull) || |
| (((y.w[1] & 0x00003fffffffffffull) == 0x0000314dc6448d93ull) && |
| (y.w[0] > 0x38c15b09ffffffffull))) { |
| y.w[1] = y.w[1] & 0xffffc00000000000ull; |
| y.w[0] = 0x0ull; |
| } |
| } else if ((y.w[1] & MASK_ANY_INF) == MASK_INF) { // y = inf |
| y.w[1] = y.w[1] & (MASK_SIGN | MASK_INF); |
| y.w[0] = 0x0ull; |
| } else { // y is not special |
| // check for non-canonical values - treated as zero |
| if ((y.w[1] & MASK_STEERING_BITS) == MASK_STEERING_BITS) { // G0_G1=11 |
| // non-canonical |
| y.w[1] = (y.w[1] & MASK_SIGN) | ((y.w[1] << 2) & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // G0_G1 != 11 |
| if ((y.w[1] & MASK_COEFF) > 0x0001ed09bead87c0ull || |
| ((y.w[1] & MASK_COEFF) == 0x0001ed09bead87c0ull && |
| y.w[0] > 0x378d8e63ffffffffull)) { |
| // y is non-canonical if coefficient is larger than 10^34 -1 |
| y.w[1] = (y.w[1] & MASK_SIGN) | (y.w[1] & MASK_EXP); |
| y.w[0] = 0x0ull; |
| } else { // canonical |
| ; |
| } |
| } |
| } |
| |
| // NaN (CASE1) |
| if ((x.w[1] & MASK_NAN) == MASK_NAN) { // x is NAN |
| if ((x.w[1] & MASK_SNAN) == MASK_SNAN) { // x is SNaN |
| // if x is SNAN, then return quiet (x) |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| x.w[1] = x.w[1] & 0xfdffffffffffffffull; // quietize x |
| res = x; |
| } else { // x is QNaN |
| if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NAN |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { // y is SNAN |
| *pfpsf |= INVALID_EXCEPTION; // set invalid flag |
| } |
| res = x; |
| } else { |
| res = y; |
| } |
| } |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_NAN) == MASK_NAN) { // y is NaN, but x is not |
| if ((y.w[1] & MASK_SNAN) == MASK_SNAN) { |
| *pfpsf |= INVALID_EXCEPTION; // set exception if SNaN |
| y.w[1] = y.w[1] & 0xfdffffffffffffffull; // quietize y |
| res = y; |
| } else { |
| // will return x (which is not NaN) |
| res = x; |
| } |
| BID_RETURN (res); |
| } |
| // SIMPLE (CASE2) |
| // if all the bits are the same, these numbers are equal (not Greater). |
| if (x.w[0] == y.w[0] && x.w[1] == y.w[1]) { |
| res = y; |
| BID_RETURN (res); |
| } |
| // INFINITY (CASE3) |
| if ((x.w[1] & MASK_INF) == MASK_INF) { |
| // if x infinity, it has maximum magnitude |
| res = ((x.w[1] & MASK_SIGN) == MASK_SIGN |
| && (y.w[1] & MASK_INF) == MASK_INF) ? y : x; |
| BID_RETURN (res); |
| } else if ((y.w[1] & MASK_INF) == MASK_INF) { |
| // x is finite, so if y is positive infinity, then x is less, return 0 |
| // if y is negative infinity, then x is greater, return 1 |
| res = y; |
| BID_RETURN (res); |
| } |
| // CONVERT X |
| sig_x.w[1] = x.w[1] & 0x0001ffffffffffffull; |
| sig_x.w[0] = x.w[0]; |
| exp_x = (x.w[1] >> 49) & 0x000000000003fffull; |
| |
| // CONVERT Y |
| exp_y = (y.w[1] >> 49) & 0x0000000000003fffull; |
| sig_y.w[1] = y.w[1] & 0x0001ffffffffffffull; |
| sig_y.w[0] = y.w[0]; |
| |
| // ZERO (CASE4) |
| // some properties: |
| // (+ZERO == -ZERO) => therefore ignore the sign |
| // (ZERO x 10^A == ZERO x 10^B) for any valid A, B => |
| // therefore ignore the exponent field |
| // (Any non-canonical # is considered 0) |
| if ((sig_x.w[1] == 0) && (sig_x.w[0] == 0)) { |
| res = y; |
| BID_RETURN (res); |
| } |
| if ((sig_y.w[1] == 0) && (sig_y.w[0] == 0)) { |
| res = x; |
| BID_RETURN (res); |
| } |
| // REDUNDANT REPRESENTATIONS (CASE6) |
| if (exp_y == exp_x && sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] == sig_y.w[0]) { |
| // check if exponents are the same and significands are the same |
| if (x.w[1] & 0x8000000000000000ull) { // x is negative |
| res = y; |
| BID_RETURN (res); |
| } else { |
| res = x; |
| BID_RETURN (res); |
| } |
| } else if (((sig_x.w[1] > sig_y.w[1] || (sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] > sig_y.w[0])) |
| && exp_x == exp_y) |
| || ((sig_x.w[1] > sig_y.w[1] |
| || (sig_x.w[1] == sig_y.w[1] |
| && sig_x.w[0] >= sig_y.w[0])) |
| && exp_x > exp_y)) { |
| // if both components are either bigger or smaller, it is clear what |
| // needs to be done; also if the magnitudes are equal |
| res = x; |
| BID_RETURN (res); |
| } else if (((sig_y.w[1] > sig_x.w[1] || (sig_y.w[1] == sig_x.w[1] |
| && sig_y.w[0] > sig_x.w[0])) |
| && exp_y == exp_x) |
| || ((sig_y.w[1] > sig_x.w[1] |
| || (sig_y.w[1] == sig_x.w[1] |
| && sig_y.w[0] >= sig_x.w[0])) |
| && exp_y > exp_x)) { |
| res = y; |
| BID_RETURN (res); |
| } else { |
| ; // continue |
| } |
| diff = exp_x - exp_y; |
| // if |exp_x - exp_y| < 33, it comes down to the compensated significand |
| if (diff > 0) { // to simplify the loop below, |
| // if exp_x is 33 greater than exp_y, no need for compensation |
| if (diff > 33) { |
| res = x; // difference cannot be greater than 10^33 |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| __mul_128x128_to_256 (sig_n_prime256, sig_x, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| if (sig_n_prime256.w[3] == 0 && (sig_n_prime256.w[2] == 0) |
| && sig_n_prime256.w[1] == sig_y.w[1] |
| && (sig_n_prime256.w[0] == sig_y.w[0])) { |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; // if equal |
| BID_RETURN (res); |
| } |
| res = (((sig_n_prime256.w[3] > 0) || sig_n_prime256.w[2] > 0) |
| || (sig_n_prime256.w[1] > sig_y.w[1]) |
| || (sig_n_prime256.w[1] == sig_y.w[1] |
| && sig_n_prime256.w[0] > sig_y.w[0])) ? x : y; |
| BID_RETURN (res); |
| } |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_x); |
| // if postitive, return whichever significand is larger (converse if negative) |
| if ((sig_n_prime192.w[2] == 0) && sig_n_prime192.w[1] == sig_y.w[1] |
| && (sig_n_prime192.w[0] == sig_y.w[0])) { |
| // if equal, return positive magnitude |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| res = ((sig_n_prime192.w[2] > 0) |
| || (sig_n_prime192.w[1] > sig_y.w[1]) |
| || (sig_n_prime192.w[1] == sig_y.w[1] |
| && sig_n_prime192.w[0] > sig_y.w[0])) ? x : y; |
| BID_RETURN (res); |
| } |
| diff = exp_y - exp_x; |
| // if exp_x is 33 less than exp_y, no need for compensation |
| if (diff > 33) { |
| res = y; |
| BID_RETURN (res); |
| } |
| if (diff > 19) { //128 by 128 bit multiply -> 256 bits |
| // adjust the y significand upwards |
| __mul_128x128_to_256 (sig_n_prime256, sig_y, ten2k128[diff - 20]); |
| // if postitive, return whichever significand is larger |
| // (converse if negative) |
| if (sig_n_prime256.w[3] == 0 && (sig_n_prime256.w[2] == 0) |
| && sig_n_prime256.w[1] == sig_x.w[1] |
| && (sig_n_prime256.w[0] == sig_x.w[0])) { |
| // if equal, return positive (if possible) |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| res = (sig_n_prime256.w[3] == 0 && sig_n_prime256.w[2] == 0 |
| && (sig_n_prime256.w[1] < sig_x.w[1] |
| || (sig_n_prime256.w[1] == sig_x.w[1] |
| && sig_n_prime256.w[0] < sig_x.w[0]))) ? x : y; |
| BID_RETURN (res); |
| } |
| // adjust the y significand upwards |
| __mul_64x128_to_192 (sig_n_prime192, ten2k64[diff], sig_y); |
| // if postitive, return whichever significand is larger (converse if negative) |
| if ((sig_n_prime192.w[2] == 0) && sig_n_prime192.w[1] == sig_x.w[1] |
| && (sig_n_prime192.w[0] == sig_x.w[0])) { |
| // if equal, return positive (if possible) |
| res = ((y.w[1] & MASK_SIGN) == MASK_SIGN) ? x : y; |
| BID_RETURN (res); |
| } |
| res = (sig_n_prime192.w[2] == 0 |
| && (sig_n_prime192.w[1] < sig_x.w[1] |
| || (sig_n_prime192.w[1] == sig_x.w[1] |
| && sig_n_prime192.w[0] < sig_x.w[0]))) ? x : y; |
| BID_RETURN (res); |
| } |