X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=libgcc%2Fconfig%2Flibbid%2Fbid_inline_add.h;fp=libgcc%2Fconfig%2Flibbid%2Fbid_inline_add.h;h=76246fab6624638da7c4946507e8876412cde69b;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git
diff --git a/libgcc/config/libbid/bid_inline_add.h b/libgcc/config/libbid/bid_inline_add.h
new file mode 100644
index 00000000..76246fab
--- /dev/null
+++ b/libgcc/config/libbid/bid_inline_add.h
@@ -0,0 +1,1253 @@
+/* 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
+. */
+
+/*****************************************************************************
+ *
+ * Helper add functions (for fma)
+ *
+ * __BID_INLINE__ UINT64 get_add64(
+ * UINT64 sign_x, int exponent_x, UINT64 coefficient_x,
+ * UINT64 sign_y, int exponent_y, UINT64 coefficient_y,
+ * int rounding_mode)
+ *
+ * __BID_INLINE__ UINT64 get_add128(
+ * UINT64 sign_x, int exponent_x, UINT64 coefficient_x,
+ * UINT64 sign_y, int final_exponent_y, UINT128 CY,
+ * int extra_digits, int rounding_mode)
+ *
+ *****************************************************************************
+ *
+ * Algorithm description:
+ *
+ * get_add64: same as BID64 add, but arguments are unpacked and there
+ * are no special case checks
+ *
+ * get_add128: add 64-bit coefficient to 128-bit product (which contains
+ * 16+extra_digits decimal digits),
+ * return BID64 result
+ * - the exponents are compared and the two coefficients are
+ * properly aligned for addition/subtraction
+ * - multiple paths are needed
+ * - final result exponent is calculated and the lower term is
+ * rounded first if necessary, to avoid manipulating
+ * coefficients longer than 128 bits
+ *
+ ****************************************************************************/
+
+#ifndef _INLINE_BID_ADD_H_
+#define _INLINE_BID_ADD_H_
+
+#include "bid_internal.h"
+
+#define MAX_FORMAT_DIGITS 16
+#define DECIMAL_EXPONENT_BIAS 398
+#define MASK_BINARY_EXPONENT 0x7ff0000000000000ull
+#define BINARY_EXPONENT_BIAS 0x3ff
+#define UPPER_EXPON_LIMIT 51
+
+///////////////////////////////////////////////////////////////////////
+//
+// get_add64() is essentially the same as bid_add(), except that
+// the arguments are unpacked
+//
+//////////////////////////////////////////////////////////////////////
+__BID_INLINE__ UINT64
+get_add64 (UINT64 sign_x, int exponent_x, UINT64 coefficient_x,
+ UINT64 sign_y, int exponent_y, UINT64 coefficient_y,
+ int rounding_mode, unsigned *fpsc) {
+ UINT128 CA, CT, CT_new;
+ UINT64 sign_a, sign_b, coefficient_a, coefficient_b, sign_s, sign_ab,
+ rem_a;
+ UINT64 saved_ca, saved_cb, C0_64, C64, remainder_h, T1, carry, tmp,
+ C64_new;
+ int_double tempx;
+ int exponent_a, exponent_b, diff_dec_expon;
+ int bin_expon_ca, extra_digits, amount, scale_k, scale_ca;
+ unsigned rmode, status;
+
+ // sort arguments by exponent
+ if (exponent_x <= exponent_y) {
+ sign_a = sign_y;
+ exponent_a = exponent_y;
+ coefficient_a = coefficient_y;
+ sign_b = sign_x;
+ exponent_b = exponent_x;
+ coefficient_b = coefficient_x;
+ } else {
+ sign_a = sign_x;
+ exponent_a = exponent_x;
+ coefficient_a = coefficient_x;
+ sign_b = sign_y;
+ exponent_b = exponent_y;
+ coefficient_b = coefficient_y;
+ }
+
+ // exponent difference
+ diff_dec_expon = exponent_a - exponent_b;
+
+ /* get binary coefficients of x and y */
+
+ //--- get number of bits in the coefficients of x and y ---
+
+ tempx.d = (double) coefficient_a;
+ bin_expon_ca = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+
+ if (!coefficient_a) {
+ return get_BID64 (sign_b, exponent_b, coefficient_b, rounding_mode,
+ fpsc);
+ }
+ if (diff_dec_expon > MAX_FORMAT_DIGITS) {
+ // normalize a to a 16-digit coefficient
+
+ scale_ca = estimate_decimal_digits[bin_expon_ca];
+ if (coefficient_a >= power10_table_128[scale_ca].w[0])
+ scale_ca++;
+
+ scale_k = 16 - scale_ca;
+
+ coefficient_a *= power10_table_128[scale_k].w[0];
+
+ diff_dec_expon -= scale_k;
+ exponent_a -= scale_k;
+
+ /* get binary coefficients of x and y */
+
+ //--- get number of bits in the coefficients of x and y ---
+ tempx.d = (double) coefficient_a;
+ bin_expon_ca = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+
+ if (diff_dec_expon > MAX_FORMAT_DIGITS) {
+#ifdef SET_STATUS_FLAGS
+ if (coefficient_b) {
+ __set_status_flags (fpsc, INEXACT_EXCEPTION);
+ }
+#endif
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (((rounding_mode) & 3) && coefficient_b) // not ROUNDING_TO_NEAREST
+ {
+ switch (rounding_mode) {
+ case ROUNDING_DOWN:
+ if (sign_b) {
+ coefficient_a -= ((((SINT64) sign_a) >> 63) | 1);
+ if (coefficient_a < 1000000000000000ull) {
+ exponent_a--;
+ coefficient_a = 9999999999999999ull;
+ } else if (coefficient_a >= 10000000000000000ull) {
+ exponent_a++;
+ coefficient_a = 1000000000000000ull;
+ }
+ }
+ break;
+ case ROUNDING_UP:
+ if (!sign_b) {
+ coefficient_a += ((((SINT64) sign_a) >> 63) | 1);
+ if (coefficient_a < 1000000000000000ull) {
+ exponent_a--;
+ coefficient_a = 9999999999999999ull;
+ } else if (coefficient_a >= 10000000000000000ull) {
+ exponent_a++;
+ coefficient_a = 1000000000000000ull;
+ }
+ }
+ break;
+ default: // RZ
+ if (sign_a != sign_b) {
+ coefficient_a--;
+ if (coefficient_a < 1000000000000000ull) {
+ exponent_a--;
+ coefficient_a = 9999999999999999ull;
+ }
+ }
+ break;
+ }
+ } else
+#endif
+#endif
+ // check special case here
+ if ((coefficient_a == 1000000000000000ull)
+ && (diff_dec_expon == MAX_FORMAT_DIGITS + 1)
+ && (sign_a ^ sign_b)
+ && (coefficient_b > 5000000000000000ull)) {
+ coefficient_a = 9999999999999999ull;
+ exponent_a--;
+ }
+
+ return get_BID64 (sign_a, exponent_a, coefficient_a,
+ rounding_mode, fpsc);
+ }
+ }
+ // test whether coefficient_a*10^(exponent_a-exponent_b) may exceed 2^62
+ if (bin_expon_ca + estimate_bin_expon[diff_dec_expon] < 60) {
+ // coefficient_a*10^(exponent_a-exponent_b)<2^63
+
+ // multiply by 10^(exponent_a-exponent_b)
+ coefficient_a *= power10_table_128[diff_dec_expon].w[0];
+
+ // sign mask
+ sign_b = ((SINT64) sign_b) >> 63;
+ // apply sign to coeff. of b
+ coefficient_b = (coefficient_b + sign_b) ^ sign_b;
+
+ // apply sign to coefficient a
+ sign_a = ((SINT64) sign_a) >> 63;
+ coefficient_a = (coefficient_a + sign_a) ^ sign_a;
+
+ coefficient_a += coefficient_b;
+ // get sign
+ sign_s = ((SINT64) coefficient_a) >> 63;
+ coefficient_a = (coefficient_a + sign_s) ^ sign_s;
+ sign_s &= 0x8000000000000000ull;
+
+ // coefficient_a < 10^16 ?
+ if (coefficient_a < power10_table_128[MAX_FORMAT_DIGITS].w[0]) {
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rounding_mode == ROUNDING_DOWN && (!coefficient_a)
+ && sign_a != sign_b)
+ sign_s = 0x8000000000000000ull;
+#endif
+#endif
+ return get_BID64 (sign_s, exponent_b, coefficient_a,
+ rounding_mode, fpsc);
+ }
+ // otherwise rounding is necessary
+
+ // already know coefficient_a<10^19
+ // coefficient_a < 10^17 ?
+ if (coefficient_a < power10_table_128[17].w[0])
+ extra_digits = 1;
+ else if (coefficient_a < power10_table_128[18].w[0])
+ extra_digits = 2;
+ else
+ extra_digits = 3;
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ rmode = rounding_mode;
+ if (sign_s && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#else
+ rmode = 0;
+#endif
+#else
+ rmode = 0;
+#endif
+ coefficient_a += round_const_table[rmode][extra_digits];
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_64x64_to_128 (CT, coefficient_a,
+ reciprocals10_64[extra_digits]);
+
+ // now get P/10^extra_digits: shift C64 right by M[extra_digits]-128
+ amount = short_recip_scale[extra_digits];
+ C64 = CT.w[1] >> amount;
+
+ } else {
+ // coefficient_a*10^(exponent_a-exponent_b) is large
+ sign_s = sign_a;
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ rmode = rounding_mode;
+ if (sign_s && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#else
+ rmode = 0;
+#endif
+#else
+ rmode = 0;
+#endif
+
+ // check whether we can take faster path
+ scale_ca = estimate_decimal_digits[bin_expon_ca];
+
+ sign_ab = sign_a ^ sign_b;
+ sign_ab = ((SINT64) sign_ab) >> 63;
+
+ // T1 = 10^(16-diff_dec_expon)
+ T1 = power10_table_128[16 - diff_dec_expon].w[0];
+
+ // get number of digits in coefficient_a
+ //P_ca = power10_table_128[scale_ca].w[0];
+ //P_ca_m1 = power10_table_128[scale_ca-1].w[0];
+ if (coefficient_a >= power10_table_128[scale_ca].w[0]) {
+ scale_ca++;
+ //P_ca_m1 = P_ca;
+ //P_ca = power10_table_128[scale_ca].w[0];
+ }
+
+ scale_k = 16 - scale_ca;
+
+ // apply sign
+ //Ts = (T1 + sign_ab) ^ sign_ab;
+
+ // test range of ca
+ //X = coefficient_a + Ts - P_ca_m1;
+
+ // addition
+ saved_ca = coefficient_a - T1;
+ coefficient_a =
+ (SINT64) saved_ca *(SINT64) power10_table_128[scale_k].w[0];
+ extra_digits = diff_dec_expon - scale_k;
+
+ // apply sign
+ saved_cb = (coefficient_b + sign_ab) ^ sign_ab;
+ // add 10^16 and rounding constant
+ coefficient_b =
+ saved_cb + 10000000000000000ull +
+ round_const_table[rmode][extra_digits];
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_64x64_to_128 (CT, coefficient_b,
+ reciprocals10_64[extra_digits]);
+
+ // now get P/10^extra_digits: shift C64 right by M[extra_digits]-128
+ amount = short_recip_scale[extra_digits];
+ C0_64 = CT.w[1] >> amount;
+
+ // result coefficient
+ C64 = C0_64 + coefficient_a;
+ // filter out difficult (corner) cases
+ // the following test is equivalent to
+ // ( (initial_coefficient_a + Ts) < P_ca &&
+ // (initial_coefficient_a + Ts) > P_ca_m1 ),
+ // which ensures the number of digits in coefficient_a does not change
+ // after adding (the appropriately scaled and rounded) coefficient_b
+ if ((UINT64) (C64 - 1000000000000000ull - 1) >
+ 9000000000000000ull - 2) {
+ if (C64 >= 10000000000000000ull) {
+ // result has more than 16 digits
+ if (!scale_k) {
+ // must divide coeff_a by 10
+ saved_ca = saved_ca + T1;
+ __mul_64x64_to_128 (CA, saved_ca, 0x3333333333333334ull);
+ //reciprocals10_64[1]);
+ coefficient_a = CA.w[1] >> 1;
+ rem_a =
+ saved_ca - (coefficient_a << 3) - (coefficient_a << 1);
+ coefficient_a = coefficient_a - T1;
+
+ saved_cb +=
+ /*90000000000000000 */ +rem_a *
+ power10_table_128[diff_dec_expon].w[0];
+ } else
+ coefficient_a =
+ (SINT64) (saved_ca - T1 -
+ (T1 << 3)) * (SINT64) power10_table_128[scale_k -
+ 1].w[0];
+
+ extra_digits++;
+ coefficient_b =
+ saved_cb + 100000000000000000ull +
+ round_const_table[rmode][extra_digits];
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_64x64_to_128 (CT, coefficient_b,
+ reciprocals10_64[extra_digits]);
+
+ // now get P/10^extra_digits: shift C64 right by M[extra_digits]-128
+ amount = short_recip_scale[extra_digits];
+ C0_64 = CT.w[1] >> amount;
+
+ // result coefficient
+ C64 = C0_64 + coefficient_a;
+ } else if (C64 <= 1000000000000000ull) {
+ // less than 16 digits in result
+ coefficient_a =
+ (SINT64) saved_ca *(SINT64) power10_table_128[scale_k +
+ 1].w[0];
+ //extra_digits --;
+ exponent_b--;
+ coefficient_b =
+ (saved_cb << 3) + (saved_cb << 1) + 100000000000000000ull +
+ round_const_table[rmode][extra_digits];
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_64x64_to_128 (CT_new, coefficient_b,
+ reciprocals10_64[extra_digits]);
+
+ // now get P/10^extra_digits: shift C64 right by M[extra_digits]-128
+ amount = short_recip_scale[extra_digits];
+ C0_64 = CT_new.w[1] >> amount;
+
+ // result coefficient
+ C64_new = C0_64 + coefficient_a;
+ if (C64_new < 10000000000000000ull) {
+ C64 = C64_new;
+#ifdef SET_STATUS_FLAGS
+ CT = CT_new;
+#endif
+ } else
+ exponent_b++;
+ }
+
+ }
+
+ }
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rmode == 0) //ROUNDING_TO_NEAREST
+#endif
+ if (C64 & 1) {
+ // check whether fractional part of initial_P/10^extra_digits
+ // is exactly .5
+ // this is the same as fractional part of
+ // (initial_P + 0.5*10^extra_digits)/10^extra_digits is exactly zero
+
+ // get remainder
+ remainder_h = CT.w[1] << (64 - amount);
+
+ // test whether fractional part is 0
+ if (!remainder_h && (CT.w[0] < reciprocals10_64[extra_digits])) {
+ C64--;
+ }
+ }
+#endif
+
+#ifdef SET_STATUS_FLAGS
+ status = INEXACT_EXCEPTION;
+
+ // get remainder
+ remainder_h = CT.w[1] << (64 - amount);
+
+ switch (rmode) {
+ case ROUNDING_TO_NEAREST:
+ case ROUNDING_TIES_AWAY:
+ // test whether fractional part is 0
+ if ((remainder_h == 0x8000000000000000ull)
+ && (CT.w[0] < reciprocals10_64[extra_digits]))
+ status = EXACT_STATUS;
+ break;
+ case ROUNDING_DOWN:
+ case ROUNDING_TO_ZERO:
+ if (!remainder_h && (CT.w[0] < reciprocals10_64[extra_digits]))
+ status = EXACT_STATUS;
+ break;
+ default:
+ // round up
+ __add_carry_out (tmp, carry, CT.w[0],
+ reciprocals10_64[extra_digits]);
+ if ((remainder_h >> (64 - amount)) + carry >=
+ (((UINT64) 1) << amount))
+ status = EXACT_STATUS;
+ break;
+ }
+ __set_status_flags (fpsc, status);
+
+#endif
+
+ return get_BID64 (sign_s, exponent_b + extra_digits, C64,
+ rounding_mode, fpsc);
+}
+
+
+///////////////////////////////////////////////////////////////////
+// round 128-bit coefficient and return result in BID64 format
+// do not worry about midpoint cases
+//////////////////////////////////////////////////////////////////
+static UINT64
+__bid_simple_round64_sticky (UINT64 sign, int exponent, UINT128 P,
+ int extra_digits, int rounding_mode,
+ unsigned *fpsc) {
+ UINT128 Q_high, Q_low, C128;
+ UINT64 C64;
+ int amount, rmode;
+
+ rmode = rounding_mode;
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (sign && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#endif
+#endif
+ __add_128_64 (P, P, round_const_table[rmode][extra_digits]);
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_128x128_full (Q_high, Q_low, P,
+ reciprocals10_128[extra_digits]);
+
+ // now get P/10^extra_digits: shift Q_high right by M[extra_digits]-128
+ amount = recip_scale[extra_digits];
+ __shr_128 (C128, Q_high, amount);
+
+ C64 = __low_64 (C128);
+
+#ifdef SET_STATUS_FLAGS
+
+ __set_status_flags (fpsc, INEXACT_EXCEPTION);
+
+#endif
+
+ return get_BID64 (sign, exponent, C64, rounding_mode, fpsc);
+}
+
+///////////////////////////////////////////////////////////////////
+// round 128-bit coefficient and return result in BID64 format
+///////////////////////////////////////////////////////////////////
+static UINT64
+__bid_full_round64 (UINT64 sign, int exponent, UINT128 P,
+ int extra_digits, int rounding_mode,
+ unsigned *fpsc) {
+ UINT128 Q_high, Q_low, C128, Stemp, PU;
+ UINT64 remainder_h, C64, carry, CY;
+ int amount, amount2, rmode, status = 0;
+
+ if (exponent < 0) {
+ if (exponent >= -16 && (extra_digits + exponent < 0)) {
+ extra_digits = -exponent;
+#ifdef SET_STATUS_FLAGS
+ if (extra_digits > 0) {
+ rmode = rounding_mode;
+ if (sign && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+ __add_128_128 (PU, P,
+ round_const_table_128[rmode][extra_digits]);
+ if (__unsigned_compare_gt_128
+ (power10_table_128[extra_digits + 15], PU))
+ status = UNDERFLOW_EXCEPTION;
+ }
+#endif
+ }
+ }
+
+ if (extra_digits > 0) {
+ exponent += extra_digits;
+ rmode = rounding_mode;
+ if (sign && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+ __add_128_128 (P, P, round_const_table_128[rmode][extra_digits]);
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_128x128_full (Q_high, Q_low, P,
+ reciprocals10_128[extra_digits]);
+
+ // now get P/10^extra_digits: shift Q_high right by M[extra_digits]-128
+ amount = recip_scale[extra_digits];
+ __shr_128_long (C128, Q_high, amount);
+
+ C64 = __low_64 (C128);
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rmode == 0) //ROUNDING_TO_NEAREST
+#endif
+ if (C64 & 1) {
+ // check whether fractional part of initial_P/10^extra_digits
+ // is exactly .5
+
+ // get remainder
+ amount2 = 64 - amount;
+ remainder_h = 0;
+ remainder_h--;
+ remainder_h >>= amount2;
+ remainder_h = remainder_h & Q_high.w[0];
+
+ if (!remainder_h
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0]))) {
+ C64--;
+ }
+ }
+#endif
+
+#ifdef SET_STATUS_FLAGS
+ status |= INEXACT_EXCEPTION;
+
+ // get remainder
+ remainder_h = Q_high.w[0] << (64 - amount);
+
+ switch (rmode) {
+ case ROUNDING_TO_NEAREST:
+ case ROUNDING_TIES_AWAY:
+ // test whether fractional part is 0
+ if (remainder_h == 0x8000000000000000ull
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ case ROUNDING_DOWN:
+ case ROUNDING_TO_ZERO:
+ if (!remainder_h
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ default:
+ // round up
+ __add_carry_out (Stemp.w[0], CY, Q_low.w[0],
+ reciprocals10_128[extra_digits].w[0]);
+ __add_carry_in_out (Stemp.w[1], carry, Q_low.w[1],
+ reciprocals10_128[extra_digits].w[1], CY);
+ if ((remainder_h >> (64 - amount)) + carry >=
+ (((UINT64) 1) << amount))
+ status = EXACT_STATUS;
+ }
+
+ __set_status_flags (fpsc, status);
+
+#endif
+ } else {
+ C64 = P.w[0];
+ if (!C64) {
+ sign = 0;
+ if (rounding_mode == ROUNDING_DOWN)
+ sign = 0x8000000000000000ull;
+ }
+ }
+ return get_BID64 (sign, exponent, C64, rounding_mode, fpsc);
+}
+
+/////////////////////////////////////////////////////////////////////////////////
+// round 192-bit coefficient (P, remainder_P) and return result in BID64 format
+// the lowest 64 bits (remainder_P) are used for midpoint checking only
+////////////////////////////////////////////////////////////////////////////////
+static UINT64
+__bid_full_round64_remainder (UINT64 sign, int exponent, UINT128 P,
+ int extra_digits, UINT64 remainder_P,
+ int rounding_mode, unsigned *fpsc,
+ unsigned uf_status) {
+ UINT128 Q_high, Q_low, C128, Stemp;
+ UINT64 remainder_h, C64, carry, CY;
+ int amount, amount2, rmode, status = uf_status;
+
+ rmode = rounding_mode;
+ if (sign && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+ if (rmode == ROUNDING_UP && remainder_P) {
+ P.w[0]++;
+ if (!P.w[0])
+ P.w[1]++;
+ }
+
+ if (extra_digits) {
+ __add_128_64 (P, P, round_const_table[rmode][extra_digits]);
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_128x128_full (Q_high, Q_low, P,
+ reciprocals10_128[extra_digits]);
+
+ // now get P/10^extra_digits: shift Q_high right by M[extra_digits]-128
+ amount = recip_scale[extra_digits];
+ __shr_128 (C128, Q_high, amount);
+
+ C64 = __low_64 (C128);
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rmode == 0) //ROUNDING_TO_NEAREST
+#endif
+ if (!remainder_P && (C64 & 1)) {
+ // check whether fractional part of initial_P/10^extra_digits
+ // is exactly .5
+
+ // get remainder
+ amount2 = 64 - amount;
+ remainder_h = 0;
+ remainder_h--;
+ remainder_h >>= amount2;
+ remainder_h = remainder_h & Q_high.w[0];
+
+ if (!remainder_h
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0]))) {
+ C64--;
+ }
+ }
+#endif
+
+#ifdef SET_STATUS_FLAGS
+ status |= INEXACT_EXCEPTION;
+
+ if (!remainder_P) {
+ // get remainder
+ remainder_h = Q_high.w[0] << (64 - amount);
+
+ switch (rmode) {
+ case ROUNDING_TO_NEAREST:
+ case ROUNDING_TIES_AWAY:
+ // test whether fractional part is 0
+ if (remainder_h == 0x8000000000000000ull
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ case ROUNDING_DOWN:
+ case ROUNDING_TO_ZERO:
+ if (!remainder_h
+ && (Q_low.w[1] < reciprocals10_128[extra_digits].w[1]
+ || (Q_low.w[1] == reciprocals10_128[extra_digits].w[1]
+ && Q_low.w[0] <
+ reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ default:
+ // round up
+ __add_carry_out (Stemp.w[0], CY, Q_low.w[0],
+ reciprocals10_128[extra_digits].w[0]);
+ __add_carry_in_out (Stemp.w[1], carry, Q_low.w[1],
+ reciprocals10_128[extra_digits].w[1], CY);
+ if ((remainder_h >> (64 - amount)) + carry >=
+ (((UINT64) 1) << amount))
+ status = EXACT_STATUS;
+ }
+ }
+ __set_status_flags (fpsc, status);
+
+#endif
+ } else {
+ C64 = P.w[0];
+#ifdef SET_STATUS_FLAGS
+ if (remainder_P) {
+ __set_status_flags (fpsc, uf_status | INEXACT_EXCEPTION);
+ }
+#endif
+ }
+
+ return get_BID64 (sign, exponent + extra_digits, C64, rounding_mode,
+ fpsc);
+}
+
+
+///////////////////////////////////////////////////////////////////
+// get P/10^extra_digits
+// result fits in 64 bits
+///////////////////////////////////////////////////////////////////
+__BID_INLINE__ UINT64
+__truncate (UINT128 P, int extra_digits)
+// extra_digits <= 16
+{
+ UINT128 Q_high, Q_low, C128;
+ UINT64 C64;
+ int amount;
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_128x128_full (Q_high, Q_low, P,
+ reciprocals10_128[extra_digits]);
+
+ // now get P/10^extra_digits: shift Q_high right by M[extra_digits]-128
+ amount = recip_scale[extra_digits];
+ __shr_128 (C128, Q_high, amount);
+
+ C64 = __low_64 (C128);
+
+ return C64;
+}
+
+
+///////////////////////////////////////////////////////////////////
+// return number of decimal digits in 128-bit value X
+///////////////////////////////////////////////////////////////////
+__BID_INLINE__ int
+__get_dec_digits64 (UINT128 X) {
+ int_double tempx;
+ int digits_x, bin_expon_cx;
+
+ if (!X.w[1]) {
+ //--- get number of bits in the coefficients of x and y ---
+ tempx.d = (double) X.w[0];
+ bin_expon_cx = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+ // get number of decimal digits in the coeff_x
+ digits_x = estimate_decimal_digits[bin_expon_cx];
+ if (X.w[0] >= power10_table_128[digits_x].w[0])
+ digits_x++;
+ return digits_x;
+ }
+ tempx.d = (double) X.w[1];
+ bin_expon_cx = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+ // get number of decimal digits in the coeff_x
+ digits_x = estimate_decimal_digits[bin_expon_cx + 64];
+ if (__unsigned_compare_ge_128 (X, power10_table_128[digits_x]))
+ digits_x++;
+
+ return digits_x;
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// add 64-bit coefficient to 128-bit coefficient, return result in BID64 format
+//
+////////////////////////////////////////////////////////////////////////////////
+__BID_INLINE__ UINT64
+get_add128 (UINT64 sign_x, int exponent_x, UINT64 coefficient_x,
+ UINT64 sign_y, int final_exponent_y, UINT128 CY,
+ int extra_digits, int rounding_mode, unsigned *fpsc) {
+ UINT128 CY_L, CX, FS, F, CT, ST, T2;
+ UINT64 CYh, CY0L, T, S, coefficient_y, remainder_y;
+ SINT64 D = 0;
+ int_double tempx;
+ int diff_dec_expon, extra_digits2, exponent_y, status;
+ int extra_dx, diff_dec2, bin_expon_cx, digits_x, rmode;
+
+ // CY has more than 16 decimal digits
+
+ exponent_y = final_exponent_y - extra_digits;
+
+#ifdef IEEE_ROUND_NEAREST_TIES_AWAY
+ rounding_mode = 0;
+#endif
+#ifdef IEEE_ROUND_NEAREST
+ rounding_mode = 0;
+#endif
+
+ if (exponent_x > exponent_y) {
+ // normalize x
+ //--- get number of bits in the coefficients of x and y ---
+ tempx.d = (double) coefficient_x;
+ bin_expon_cx = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+ // get number of decimal digits in the coeff_x
+ digits_x = estimate_decimal_digits[bin_expon_cx];
+ if (coefficient_x >= power10_table_128[digits_x].w[0])
+ digits_x++;
+
+ extra_dx = 16 - digits_x;
+ coefficient_x *= power10_table_128[extra_dx].w[0];
+ if ((sign_x ^ sign_y) && (coefficient_x == 1000000000000000ull)) {
+ extra_dx++;
+ coefficient_x = 10000000000000000ull;
+ }
+ exponent_x -= extra_dx;
+
+ if (exponent_x > exponent_y) {
+
+ // exponent_x > exponent_y
+ diff_dec_expon = exponent_x - exponent_y;
+
+ if (exponent_x <= final_exponent_y + 1) {
+ __mul_64x64_to_128 (CX, coefficient_x,
+ power10_table_128[diff_dec_expon].w[0]);
+
+ if (sign_x == sign_y) {
+ __add_128_128 (CT, CY, CX);
+ if ((exponent_x >
+ final_exponent_y) /*&& (final_exponent_y>0) */ )
+ extra_digits++;
+ if (__unsigned_compare_ge_128
+ (CT, power10_table_128[16 + extra_digits]))
+ extra_digits++;
+ } else {
+ __sub_128_128 (CT, CY, CX);
+ if (((SINT64) CT.w[1]) < 0) {
+ CT.w[0] = 0 - CT.w[0];
+ CT.w[1] = 0 - CT.w[1];
+ if (CT.w[0])
+ CT.w[1]--;
+ sign_y = sign_x;
+ } else if (!(CT.w[1] | CT.w[0])) {
+ sign_y =
+ (rounding_mode !=
+ ROUNDING_DOWN) ? 0 : 0x8000000000000000ull;
+ }
+ if ((exponent_x + 1 >=
+ final_exponent_y) /*&& (final_exponent_y>=0) */ ) {
+ extra_digits = __get_dec_digits64 (CT) - 16;
+ if (extra_digits <= 0) {
+ if (!CT.w[0] && rounding_mode == ROUNDING_DOWN)
+ sign_y = 0x8000000000000000ull;
+ return get_BID64 (sign_y, exponent_y, CT.w[0],
+ rounding_mode, fpsc);
+ }
+ } else
+ if (__unsigned_compare_gt_128
+ (power10_table_128[15 + extra_digits], CT))
+ extra_digits--;
+ }
+
+ return __bid_full_round64 (sign_y, exponent_y, CT, extra_digits,
+ rounding_mode, fpsc);
+ }
+ // diff_dec2+extra_digits is the number of digits to eliminate from
+ // argument CY
+ diff_dec2 = exponent_x - final_exponent_y;
+
+ if (diff_dec2 >= 17) {
+#ifndef IEEE_ROUND_NEAREST
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+ if ((rounding_mode) & 3) {
+ switch (rounding_mode) {
+ case ROUNDING_UP:
+ if (!sign_y) {
+ D = ((SINT64) (sign_x ^ sign_y)) >> 63;
+ D = D + D + 1;
+ coefficient_x += D;
+ }
+ break;
+ case ROUNDING_DOWN:
+ if (sign_y) {
+ D = ((SINT64) (sign_x ^ sign_y)) >> 63;
+ D = D + D + 1;
+ coefficient_x += D;
+ }
+ break;
+ case ROUNDING_TO_ZERO:
+ if (sign_y != sign_x) {
+ D = 0 - 1;
+ coefficient_x += D;
+ }
+ break;
+ }
+ if (coefficient_x < 1000000000000000ull) {
+ coefficient_x -= D;
+ coefficient_x =
+ D + (coefficient_x << 1) + (coefficient_x << 3);
+ exponent_x--;
+ }
+ }
+#endif
+#endif
+#ifdef SET_STATUS_FLAGS
+ if (CY.w[1] | CY.w[0])
+ __set_status_flags (fpsc, INEXACT_EXCEPTION);
+#endif
+ return get_BID64 (sign_x, exponent_x, coefficient_x,
+ rounding_mode, fpsc);
+ }
+ // here exponent_x <= 16+final_exponent_y
+
+ // truncate CY to 16 dec. digits
+ CYh = __truncate (CY, extra_digits);
+
+ // get remainder
+ T = power10_table_128[extra_digits].w[0];
+ __mul_64x64_to_64 (CY0L, CYh, T);
+
+ remainder_y = CY.w[0] - CY0L;
+
+ // align coeff_x, CYh
+ __mul_64x64_to_128 (CX, coefficient_x,
+ power10_table_128[diff_dec2].w[0]);
+
+ if (sign_x == sign_y) {
+ __add_128_64 (CT, CX, CYh);
+ if (__unsigned_compare_ge_128
+ (CT, power10_table_128[16 + diff_dec2]))
+ diff_dec2++;
+ } else {
+ if (remainder_y)
+ CYh++;
+ __sub_128_64 (CT, CX, CYh);
+ if (__unsigned_compare_gt_128
+ (power10_table_128[15 + diff_dec2], CT))
+ diff_dec2--;
+ }
+
+ return __bid_full_round64_remainder (sign_x, final_exponent_y, CT,
+ diff_dec2, remainder_y,
+ rounding_mode, fpsc, 0);
+ }
+ }
+ // Here (exponent_x <= exponent_y)
+ {
+ diff_dec_expon = exponent_y - exponent_x;
+
+ if (diff_dec_expon > MAX_FORMAT_DIGITS) {
+ rmode = rounding_mode;
+
+ if ((sign_x ^ sign_y)) {
+ if (!CY.w[0])
+ CY.w[1]--;
+ CY.w[0]--;
+ if (__unsigned_compare_gt_128
+ (power10_table_128[15 + extra_digits], CY)) {
+ if (rmode & 3) {
+ extra_digits--;
+ final_exponent_y--;
+ } else {
+ CY.w[0] = 1000000000000000ull;
+ CY.w[1] = 0;
+ extra_digits = 0;
+ }
+ }
+ }
+ __scale128_10 (CY, CY);
+ extra_digits++;
+ CY.w[0] |= 1;
+
+ return __bid_simple_round64_sticky (sign_y, final_exponent_y, CY,
+ extra_digits, rmode, fpsc);
+ }
+ // apply sign to coeff_x
+ sign_x ^= sign_y;
+ sign_x = ((SINT64) sign_x) >> 63;
+ CX.w[0] = (coefficient_x + sign_x) ^ sign_x;
+ CX.w[1] = sign_x;
+
+ // check whether CY (rounded to 16 digits) and CX have
+ // any digits in the same position
+ diff_dec2 = final_exponent_y - exponent_x;
+
+ if (diff_dec2 <= 17) {
+ // align CY to 10^ex
+ S = power10_table_128[diff_dec_expon].w[0];
+ __mul_64x128_short (CY_L, S, CY);
+
+ __add_128_128 (ST, CY_L, CX);
+ extra_digits2 = __get_dec_digits64 (ST) - 16;
+ return __bid_full_round64 (sign_y, exponent_x, ST, extra_digits2,
+ rounding_mode, fpsc);
+ }
+ // truncate CY to 16 dec. digits
+ CYh = __truncate (CY, extra_digits);
+
+ // get remainder
+ T = power10_table_128[extra_digits].w[0];
+ __mul_64x64_to_64 (CY0L, CYh, T);
+
+ coefficient_y = CY.w[0] - CY0L;
+ // add rounding constant
+ rmode = rounding_mode;
+ if (sign_y && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (!(rmode & 3)) //ROUNDING_TO_NEAREST
+#endif
+#endif
+ {
+ coefficient_y += round_const_table[rmode][extra_digits];
+ }
+ // align coefficient_y, coefficient_x
+ S = power10_table_128[diff_dec_expon].w[0];
+ __mul_64x64_to_128 (F, coefficient_y, S);
+
+ // fraction
+ __add_128_128 (FS, F, CX);
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rmode == 0) //ROUNDING_TO_NEAREST
+#endif
+ {
+ // rounding code, here RN_EVEN
+ // 10^(extra_digits+diff_dec_expon)
+ T2 = power10_table_128[diff_dec_expon + extra_digits];
+ if (__unsigned_compare_gt_128 (FS, T2)
+ || ((CYh & 1) && __test_equal_128 (FS, T2))) {
+ CYh++;
+ __sub_128_128 (FS, FS, T2);
+ }
+ }
+#endif
+#ifndef IEEE_ROUND_NEAREST
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+ if (rmode == 4) //ROUNDING_TO_NEAREST
+#endif
+ {
+ // rounding code, here RN_AWAY
+ // 10^(extra_digits+diff_dec_expon)
+ T2 = power10_table_128[diff_dec_expon + extra_digits];
+ if (__unsigned_compare_ge_128 (FS, T2)) {
+ CYh++;
+ __sub_128_128 (FS, FS, T2);
+ }
+ }
+#endif
+#ifndef IEEE_ROUND_NEAREST
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+ switch (rmode) {
+ case ROUNDING_DOWN:
+ case ROUNDING_TO_ZERO:
+ if ((SINT64) FS.w[1] < 0) {
+ CYh--;
+ if (CYh < 1000000000000000ull) {
+ CYh = 9999999999999999ull;
+ final_exponent_y--;
+ }
+ } else {
+ T2 = power10_table_128[diff_dec_expon + extra_digits];
+ if (__unsigned_compare_ge_128 (FS, T2)) {
+ CYh++;
+ __sub_128_128 (FS, FS, T2);
+ }
+ }
+ break;
+ case ROUNDING_UP:
+ if ((SINT64) FS.w[1] < 0)
+ break;
+ T2 = power10_table_128[diff_dec_expon + extra_digits];
+ if (__unsigned_compare_gt_128 (FS, T2)) {
+ CYh += 2;
+ __sub_128_128 (FS, FS, T2);
+ } else if ((FS.w[1] == T2.w[1]) && (FS.w[0] == T2.w[0])) {
+ CYh++;
+ FS.w[1] = FS.w[0] = 0;
+ } else if (FS.w[1] | FS.w[0])
+ CYh++;
+ break;
+ }
+#endif
+#endif
+
+#ifdef SET_STATUS_FLAGS
+ status = INEXACT_EXCEPTION;
+#ifndef IEEE_ROUND_NEAREST
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+ if (!(rmode & 3))
+#endif
+#endif
+ {
+ // RN modes
+ if ((FS.w[1] ==
+ round_const_table_128[0][diff_dec_expon + extra_digits].w[1])
+ && (FS.w[0] ==
+ round_const_table_128[0][diff_dec_expon +
+ extra_digits].w[0]))
+ status = EXACT_STATUS;
+ }
+#ifndef IEEE_ROUND_NEAREST
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+ else if (!FS.w[1] && !FS.w[0])
+ status = EXACT_STATUS;
+#endif
+#endif
+
+ __set_status_flags (fpsc, status);
+#endif
+
+ return get_BID64 (sign_y, final_exponent_y, CYh, rounding_mode,
+ fpsc);
+ }
+
+}
+
+//////////////////////////////////////////////////////////////////////////
+//
+// If coefficient_z is less than 16 digits long, normalize to 16 digits
+//
+/////////////////////////////////////////////////////////////////////////
+static UINT64
+BID_normalize (UINT64 sign_z, int exponent_z,
+ UINT64 coefficient_z, UINT64 round_dir, int round_flag,
+ int rounding_mode, unsigned *fpsc) {
+ SINT64 D;
+ int_double tempx;
+ int digits_z, bin_expon, scale, rmode;
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ rmode = rounding_mode;
+ if (sign_z && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#else
+ if (coefficient_z >= power10_table_128[15].w[0])
+ return z;
+#endif
+#endif
+
+ //--- get number of bits in the coefficients of x and y ---
+ tempx.d = (double) coefficient_z;
+ bin_expon = ((tempx.i & MASK_BINARY_EXPONENT) >> 52) - 0x3ff;
+ // get number of decimal digits in the coeff_x
+ digits_z = estimate_decimal_digits[bin_expon];
+ if (coefficient_z >= power10_table_128[digits_z].w[0])
+ digits_z++;
+
+ scale = 16 - digits_z;
+ exponent_z -= scale;
+ if (exponent_z < 0) {
+ scale += exponent_z;
+ exponent_z = 0;
+ }
+ coefficient_z *= power10_table_128[scale].w[0];
+
+#ifdef SET_STATUS_FLAGS
+ if (round_flag) {
+ __set_status_flags (fpsc, INEXACT_EXCEPTION);
+ if (coefficient_z < 1000000000000000ull)
+ __set_status_flags (fpsc, UNDERFLOW_EXCEPTION);
+ else if ((coefficient_z == 1000000000000000ull) && !exponent_z
+ && ((SINT64) (round_dir ^ sign_z) < 0) && round_flag
+ && (rmode == ROUNDING_DOWN || rmode == ROUNDING_TO_ZERO))
+ __set_status_flags (fpsc, UNDERFLOW_EXCEPTION);
+ }
+#endif
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (round_flag && (rmode & 3)) {
+ D = round_dir ^ sign_z;
+
+ if (rmode == ROUNDING_UP) {
+ if (D >= 0)
+ coefficient_z++;
+ } else {
+ if (D < 0)
+ coefficient_z--;
+ if (coefficient_z < 1000000000000000ull && exponent_z) {
+ coefficient_z = 9999999999999999ull;
+ exponent_z--;
+ }
+ }
+ }
+#endif
+#endif
+
+ return get_BID64 (sign_z, exponent_z, coefficient_z, rounding_mode,
+ fpsc);
+}
+
+
+//////////////////////////////////////////////////////////////////////////
+//
+// 0*10^ey + cz*10^ez, ey> 52) - 0x3ff;
+ scale_cz = estimate_decimal_digits[bin_expon];
+ if (coefficient_z >= power10_table_128[scale_cz].w[0])
+ scale_cz++;
+
+ scale_k = 16 - scale_cz;
+ if (diff_expon < scale_k)
+ scale_k = diff_expon;
+ coefficient_z *= power10_table_128[scale_k].w[0];
+
+ return get_BID64 (sign_z, exponent_z - scale_k, coefficient_z,
+ *prounding_mode, fpsc);
+}
+#endif