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+/* Software floating-point emulation.
+ Basic eight-word fraction declaration and manipulation.
+ Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Richard Henderson (rth@cygnus.com),
+ Jakub Jelinek (jj@ultra.linux.cz) and
+ Peter Maydell (pmaydell@chiark.greenend.org.uk).
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, write to the Free Software Foundation, Inc.,
+ 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+/* We need just a few things from here for op-4, if we ever need some
+ other macros, they can be added. */
+#define _FP_FRAC_DECL_8(X) _FP_W_TYPE X##_f[8]
+#define _FP_FRAC_HIGH_8(X) (X##_f[7])
+#define _FP_FRAC_LOW_8(X) (X##_f[0])
+#define _FP_FRAC_WORD_8(X,w) (X##_f[w])
+
+#define _FP_FRAC_SLL_8(X,N) \
+ do { \
+ _FP_I_TYPE _up, _down, _skip, _i; \
+ _skip = (N) / _FP_W_TYPE_SIZE; \
+ _up = (N) % _FP_W_TYPE_SIZE; \
+ _down = _FP_W_TYPE_SIZE - _up; \
+ if (!_up) \
+ for (_i = 7; _i >= _skip; --_i) \
+ X##_f[_i] = X##_f[_i-_skip]; \
+ else \
+ { \
+ for (_i = 7; _i > _skip; --_i) \
+ X##_f[_i] = X##_f[_i-_skip] << _up \
+ | X##_f[_i-_skip-1] >> _down; \
+ X##_f[_i--] = X##_f[0] << _up; \
+ } \
+ for (; _i >= 0; --_i) \
+ X##_f[_i] = 0; \
+ } while (0)
+
+#define _FP_FRAC_SRL_8(X,N) \
+ do { \
+ _FP_I_TYPE _up, _down, _skip, _i; \
+ _skip = (N) / _FP_W_TYPE_SIZE; \
+ _down = (N) % _FP_W_TYPE_SIZE; \
+ _up = _FP_W_TYPE_SIZE - _down; \
+ if (!_down) \
+ for (_i = 0; _i <= 7-_skip; ++_i) \
+ X##_f[_i] = X##_f[_i+_skip]; \
+ else \
+ { \
+ for (_i = 0; _i < 7-_skip; ++_i) \
+ X##_f[_i] = X##_f[_i+_skip] >> _down \
+ | X##_f[_i+_skip+1] << _up; \
+ X##_f[_i++] = X##_f[7] >> _down; \
+ } \
+ for (; _i < 8; ++_i) \
+ X##_f[_i] = 0; \
+ } while (0)
+
+
+/* Right shift with sticky-lsb.
+ * What this actually means is that we do a standard right-shift,
+ * but that if any of the bits that fall off the right hand side
+ * were one then we always set the LSbit.
+ */
+#define _FP_FRAC_SRS_8(X,N,size) \
+ do { \
+ _FP_I_TYPE _up, _down, _skip, _i; \
+ _FP_W_TYPE _s; \
+ _skip = (N) / _FP_W_TYPE_SIZE; \
+ _down = (N) % _FP_W_TYPE_SIZE; \
+ _up = _FP_W_TYPE_SIZE - _down; \
+ for (_s = _i = 0; _i < _skip; ++_i) \
+ _s |= X##_f[_i]; \
+ _s |= X##_f[_i] << _up; \
+/* s is now != 0 if we want to set the LSbit */ \
+ if (!_down) \
+ for (_i = 0; _i <= 7-_skip; ++_i) \
+ X##_f[_i] = X##_f[_i+_skip]; \
+ else \
+ { \
+ for (_i = 0; _i < 7-_skip; ++_i) \
+ X##_f[_i] = X##_f[_i+_skip] >> _down \
+ | X##_f[_i+_skip+1] << _up; \
+ X##_f[_i++] = X##_f[7] >> _down; \
+ } \
+ for (; _i < 8; ++_i) \
+ X##_f[_i] = 0; \
+ /* don't fix the LSB until the very end when we're sure f[0] is stable */ \
+ X##_f[0] |= (_s != 0); \
+ } while (0)
+