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-rw-r--r--lib/builtins/fixunsxfsi.c44
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diff --git a/lib/builtins/fixunsxfsi.c b/lib/builtins/fixunsxfsi.c
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+/* ===-- fixunsxfsi.c - Implement __fixunsxfsi -----------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __fixunsxfsi for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#if !_ARCH_PPC
+
+#include "int_lib.h"
+
+/* Returns: convert a to a unsigned int, rounding toward zero.
+ * Negative values all become 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 su_int or is negative
+ * (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
+ */
+
+COMPILER_RT_ABI su_int
+__fixunsxfsi(long double a)
+{
+ long_double_bits fb;
+ fb.f = a;
+ int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
+ if (e < 0 || (fb.u.high.s.low & 0x00008000))
+ return 0;
+ return fb.u.low.s.high >> (31 - e);
+}
+
+#endif /* !_ARCH_PPC */