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-rw-r--r--lib/fixxfti.c47
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diff --git a/lib/fixxfti.c b/lib/fixxfti.c
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+/* ===-- fixxfti.c - Implement __fixxfti -----------------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __fixxfti for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#if __x86_64
+
+#include "int_lib.h"
+
+/* Returns: convert a to a signed long long, rounding toward zero. */
+
+/* Assumption: long double is an intel 80 bit floating point type padded with 6 bytes
+ * su_int is a 32 bit integral type
+ * value in long double is representable in ti_int (no range checking performed)
+ */
+
+/* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
+ * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
+ */
+
+ti_int
+__fixxfti(long double a)
+{
+ long_double_bits fb;
+ fb.f = a;
+ int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
+ if (e < 0)
+ return 0;
+ ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15);
+ ti_int r = fb.u.low.all;
+ if (e > 63)
+ r <<= (e - 63);
+ else
+ r >>= (63 - e);
+ return (r ^ s) - s;
+}
+
+#endif /* __x86_64 */