Initial import

2020-06-15 07:18:57 -07:00
commit c91b3c5006
14915 changed files with 590219 additions and 0 deletions
--- a/libc/math/round.c
+++ b/libc/math/round.c
@@ -0,0 +1,29 @@
+#include "libc/math/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 round(double x) {
+  union {
+    double f;
+    uint64_t i;
+  } u = {x};
+  int e = u.i >> 52 & 0x7ff;
+  double_t y;
+  if (e >= 0x3ff + 52) return x;
+  if (u.i >> 63) x = -x;
+  y = x + toint - toint - x;
+  if (y > 0.5) {
+    y = y + x - 1;
+  } else if (y <= -0.5) {
+    y = y + x + 1;
+  } else {
+    y = y + x;
+  }
+  if (u.i >> 63) y = -y;
+  return y;
+}