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authorScott Shawcroft <scott@tannewt.org>2017-08-28 13:59:26 -0700
committerGitHub <noreply@github.com>2017-08-28 13:59:26 -0700
commit447a4b1ecd5655357c9daaace03b91355d2e2c6d (patch)
tree46ca08a93e9870aab4fbb533843f3c99796cbdf4 /lib/libm_dbl/ceil.c
parent4e63d55d8d0df6d7600bb684fa90a8cb54708ba8 (diff)
parentc679c80c710fd4a0e37ad87200d8a721e19727aa (diff)
Merge pull request #208 from adafruit/merge-v1.9.2
Merge MicroPython v1.9.2
Diffstat (limited to 'lib/libm_dbl/ceil.c')
-rw-r--r--lib/libm_dbl/ceil.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/lib/libm_dbl/ceil.c b/lib/libm_dbl/ceil.c
new file mode 100644
index 000000000..b13e6f2d6
--- /dev/null
+++ b/lib/libm_dbl/ceil.c
@@ -0,0 +1,31 @@
+#include "libm.h"
+
+#if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1
+#define EPS DBL_EPSILON
+#elif FLT_EVAL_METHOD==2
+#define EPS LDBL_EPSILON
+#endif
+static const double_t toint = 1/EPS;
+
+double ceil(double x)
+{
+ union {double f; uint64_t i;} u = {x};
+ int e = u.i >> 52 & 0x7ff;
+ double_t y;
+
+ if (e >= 0x3ff+52 || x == 0)
+ return x;
+ /* y = int(x) - x, where int(x) is an integer neighbor of x */
+ if (u.i >> 63)
+ y = x - toint + toint - x;
+ else
+ y = x + toint - toint - x;
+ /* special case because of non-nearest rounding modes */
+ if (e <= 0x3ff-1) {
+ FORCE_EVAL(y);
+ return u.i >> 63 ? -0.0 : 1;
+ }
+ if (y < 0)
+ return x + y + 1;
+ return x + y;
+}