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authorKacper <kacper@mail.openlinux.dev>2025-12-09 19:20:15 +0100
committerKacper <kacper@mail.openlinux.dev>2025-12-09 19:20:15 +0100
commit885f5974cdf65b59415837ae97f5a14ef1350670 (patch)
tree66ac13de29c7f4932c5fcae11773df574e4e256a /lib/libm/floor.c
parent8f9e448b2ef6db7cd905540c21f3c5b190e7a1e7 (diff)
feat: add gzip and new headers
Diffstat (limited to 'lib/libm/floor.c')
-rw-r--r--lib/libm/floor.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/lib/libm/floor.c b/lib/libm/floor.c
new file mode 100644
index 00000000..9972a974
--- /dev/null
+++ b/lib/libm/floor.c
@@ -0,0 +1,34 @@
+#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 floor(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 ? -1 : 0;
+ }
+ if (y > 0)
+ return x + y - 1;
+ return x + y;
+}