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-rw-r--r--sysdeps/libm-ieee754/s_lround.c143
1 files changed, 22 insertions, 121 deletions
diff --git a/sysdeps/libm-ieee754/s_lround.c b/sysdeps/libm-ieee754/s_lround.c
index 974dbde050..a6468ba78a 100644
--- a/sysdeps/libm-ieee754/s_lround.c
+++ b/sysdeps/libm-ieee754/s_lround.c
@@ -1,4 +1,4 @@
-/* Round long double value to long int.
+/* Round double value to long int.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -23,13 +23,8 @@
#include "math_private.h"
-#ifdef NO_LONG_DOUBLE
-/* The `long double' is in fact the IEEE `double' type. */
-
-/* This code does not presently work. */
-
long int
-__lround (long double x)
+__lround (double x)
{
int32_t j0;
u_int32_t i1, i0;
@@ -40,138 +35,44 @@ __lround (long double x)
j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
sign = (i0 & 0x80000000) != 0 ? -1 : 1;
i0 &= 0xfffff;
+ i0 |= 0x100000;
+
if (j0 < 20)
{
if (j0 < 0)
- result = j0 < -1 ? 0 : sign;
+ return j0 < -1 ? 0 : sign;
else
{
- u_int32_t i = 0xfffff >> j0;
- i0 |= 0x100000;
- if (((i0 & i) | i1) == 0)
- result = i0 >> j0;
- else
- /* X is not integral. */
- result = (i0 + (0x80000 >> j0)) >> (20 - j0);
+ i0 += 0x80000 >> j0;
+
+ result = i0 >> (20 - j0);
}
}
- else if (j0 >= 8 * sizeof (long int) || j0 > 51)
- {
- /* The number is too large. It is left implementation defined
- what happens. */
- return (long int) x;
- }
- else
+ else if (j0 < (int32_t) (8 * sizeof (long int)))
{
- u_int32_t i = ((u_int32_t) (0xffffffff)) >> (j0 - 20);
- if ((i1 & i) != 0)
+ if (j0 >= 52)
+ result = ((long int) i0 << (j0 - 20)) | (i1 << (j0 - 52));
+ else
{
- /* x is not integral. */
u_int32_t j = i1 + (0x80000000 >> (j0 - 20));
if (j < i1)
- {
- j = i0 + 1;
- if ((j & 0xfffff) == 0)
- {
- if (sizeof (long int) <= 4)
- /* Overflow. */
- result = (long int) x;
- else
- result = 1l << (j0 + 1);
- }
- else
- result = (long int) ((i0 & 0xfffff) | 0x100000) << (j0 - 31);
- }
- else
- {
- result = (long int) ((i0 & 0xfffff) | 0x100000) << (j0 - 31);
- if (sizeof (long int) > 4 && j0 > 31)
- result |= j >> (63 - j0);
- }
- }
- else
- {
- result = (long int) ((i0 & 0xfffff) | 0x100000) << (j0 - 31);
- if (sizeof (long int) > 4 && j0 > 31)
- result |= i1 >> (63 - j0);
- }
- }
-
- return sign * result;
-}
-#else
-long int
-__lround (long double x)
-{
- int32_t j0;
- u_int32_t se, i1, i0;
- long int result;
+ ++i0;
- GET_LDOUBLE_WORDS (se, i0, i1, x);
- j0 = (se & 0x7fff) - 0x3fff;
- if (j0 < 31)
- {
- if (j0 < 0)
- result = j0 < -1 ? 0 : 1;
- else
- {
- u_int32_t i = 0x7fffffff >> j0;
- if (((i0 & i) | i1) == 0)
- result = (long int) i0 >> j0;
- else
- {
- /* X is not integral. */
- u_int32_t j = i0 + (0x40000000 >> j0);
- if (j < i0)
- result = 0x80000000l >> (30 - j0);
- else
- result = j >> (31 - j0);
- }
+ result = ((long int) i0 << (j0 - 20)) | (j >> (52 - j0));
}
}
- else if ((unsigned int) j0 >= 8 * sizeof (long int) || j0 > 62)
+ else
{
/* The number is too large. It is left implementation defined
what happens. */
- result = (long int) x;
- }
- else
- {
- u_int32_t i = ((u_int32_t) (0xffffffff)) >> (j0 - 31);
- if ((i1 & i) != 0)
- {
- /* x is not integral. */
- u_int32_t j = i1 + (0x80000000 >> (j0 - 31));
- if (j < i1)
- {
- j = i0 + 1;
- if (j == 0)
- {
- if (sizeof (long int) <= 4)
- /* Overflow. */
- result = (long int) x;
- else
- result = 1l << (j0 + 1);
- }
- else
- result = (long int) i0 << (j0 - 31);
- }
- else
- {
- result = (long int) i0 << (j0 - 31);
- if (sizeof (long int) > 4 && j0 > 31)
- result |= j >> (63 - j0);
- }
- }
- else
- {
- result = (long int) i0 << (j0 - 31);
- if (sizeof (long int) > 4 && j0 > 31)
- result |= i1 >> (63 - j0);
- }
+ return (long int) x;
}
- return se & 0x8000 ? -result : result;
+ return sign * result;
}
-#endif
+
weak_alias (__lround, lround)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__lround, __lroundl)
+weak_alias (__lround, lroundl)
+#endif