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-rw-r--r--lib/fixsfti.c43
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diff --git a/lib/fixsfti.c b/lib/fixsfti.c
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+//===-- fixsfti.c - Implement __fixsfti -----------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __fixsfti for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#if __x86_64
+
+#include "int_lib.h"
+
+// Returns: convert a to a signed long long, rounding toward zero.
+
+// Assumption: float is a IEEE 32 bit floating point type
+// su_int is a 32 bit integral type
+// value in float is representable in ti_int (no range checking performed)
+
+// seee eeee emmm mmmm mmmm mmmm mmmm mmmm
+
+ti_int
+__fixsfti(float a)
+{
+ float_bits fb;
+ fb.f = a;
+ int e = ((fb.u & 0x7F800000) >> 23) - 127;
+ if (e < 0)
+ return 0;
+ ti_int s = (si_int)(fb.u & 0x80000000) >> 31;
+ ti_int r = (fb.u & 0x007FFFFF) | 0x00800000;
+ if (e > 23)
+ r <<= (e - 23);
+ else
+ r >>= (23 - e);
+ return (r ^ s) - s;
+}
+
+#endif