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-rw-r--r--lib/ppc/floatditf.c37
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diff --git a/lib/ppc/floatditf.c b/lib/ppc/floatditf.c
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+/* This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ */
+
+/* long double __floatditf(long long x); */
+/* This file implements the PowerPC long long -> long double conversion */
+
+#include "DD.h"
+#include <stdint.h>
+
+long double __floatditf(int64_t a) {
+
+ static const double twop32 = 0x1.0p32;
+ static const double twop52 = 0x1.0p52;
+
+ doublebits low = { .d = twop52 };
+ low.x |= a & UINT64_C(0x00000000ffffffff); /* 0x1.0p52 + low 32 bits of a. */
+
+ const double high_addend = (double)((int32_t)(a >> 32))*twop32 - twop52;
+
+ /* At this point, we have two double precision numbers
+ * high_addend and low.d, and we wish to return their sum
+ * as a canonicalized long double:
+ */
+
+ /* This implementation sets the inexact flag spuriously.
+ * This could be avoided, but at some substantial cost.
+ */
+
+ DD result;
+
+ result.s.hi = high_addend + low.d;
+ result.s.lo = (high_addend - result.s.hi) + low.d;
+
+ return result.ld;
+
+}