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Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_fromfpl_main.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_fromfpl_main.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_fromfpl_main.c b/sysdeps/ieee754/ldbl-128/s_fromfpl_main.c
new file mode 100644
index 0000000000..5b9c1a84b2
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_fromfpl_main.c
@@ -0,0 +1,91 @@
+/* Round to integer type. ldbl-128 version.
+ Copyright (C) 2016-2018 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <fenv.h>
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-ldouble.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#define BIAS 0x3fff
+#define MANT_DIG 113
+
+#if UNSIGNED
+# define RET_TYPE uintmax_t
+#else
+# define RET_TYPE intmax_t
+#endif
+
+#include <fromfp.h>
+
+RET_TYPE
+FUNC (_Float128 x, int round, unsigned int width)
+{
+ if (width > INTMAX_WIDTH)
+ width = INTMAX_WIDTH;
+ uint64_t hx, lx;
+ GET_LDOUBLE_WORDS64 (hx, lx, x);
+ bool negative = (hx & 0x8000000000000000ULL) != 0;
+ if (width == 0)
+ return fromfp_domain_error (negative, width);
+ hx &= 0x7fffffffffffffffULL;
+ if ((hx | lx) == 0)
+ return 0;
+ int exponent = hx >> (MANT_DIG - 1 - 64);
+ exponent -= BIAS;
+ int max_exponent = fromfp_max_exponent (negative, width);
+ if (exponent > max_exponent)
+ return fromfp_domain_error (negative, width);
+
+ hx &= ((1ULL << (MANT_DIG - 1 - 64)) - 1);
+ hx |= 1ULL << (MANT_DIG - 1 - 64);
+ uintmax_t uret;
+ bool half_bit, more_bits;
+ /* The exponent is at most 63, so we are shifting right by at least
+ 49 bits. */
+ if (exponent >= -1)
+ {
+ int shift = MANT_DIG - 1 - exponent;
+ if (shift <= 64)
+ {
+ uint64_t h = 1ULL << (shift - 1);
+ half_bit = (lx & h) != 0;
+ more_bits = (lx & (h - 1)) != 0;
+ uret = hx << (64 - shift);
+ if (shift != 64)
+ uret |= lx >> shift;
+ }
+ else
+ {
+ uint64_t h = 1ULL << (shift - 1 - 64);
+ half_bit = (hx & h) != 0;
+ more_bits = ((hx & (h - 1)) | lx) != 0;
+ uret = hx >> (shift - 64);
+ }
+ }
+ else
+ {
+ uret = 0;
+ half_bit = false;
+ more_bits = true;
+ }
+ return fromfp_round_and_return (negative, uret, half_bit, more_bits, round,
+ exponent, max_exponent, width);
+}