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diff --git a/gcc-4.9/libgcc/config/libbid/bid128_minmax.c b/gcc-4.9/libgcc/config/libbid/bid128_minmax.c
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+/* Copyright (C) 2007-2014 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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 06:37:22 +0000