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-rw-r--r--lib/fixdfti.c45
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diff --git a/lib/fixdfti.c b/lib/fixdfti.c
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+/* ===-- fixdfti.c - Implement __fixdfti -----------------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __fixdfti for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#if __x86_64
+
+#include "int_lib.h"
+
+/* Returns: convert a to a signed long long, rounding toward zero. */
+
+/* Assumption: double is a IEEE 64 bit floating point type
+ * su_int is a 32 bit integral type
+ * value in double is representable in ti_int (no range checking performed)
+ */
+
+/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */
+
+ti_int
+__fixdfti(double a)
+{
+ double_bits fb;
+ fb.f = a;
+ int e = ((fb.u.s.high & 0x7FF00000) >> 20) - 1023;
+ if (e < 0)
+ return 0;
+ ti_int s = (si_int)(fb.u.s.high & 0x80000000) >> 31;
+ ti_int r = 0x0010000000000000uLL | (0x000FFFFFFFFFFFFFuLL & fb.u.all);
+ if (e > 52)
+ r <<= (e - 52);
+ else
+ r >>= (52 - e);
+ return (r ^ s) - s;
+}
+
+#endif