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+//===-- lib/floatditf.c - integer -> quad-precision conversion ----*- C -*-===//
+//
+// 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 di_int to quad-precision conversion for the
+// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even
+// mode.
+//
+//===----------------------------------------------------------------------===//
+
+#define QUAD_PRECISION
+#include "fp_lib.h"
+
+#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
+COMPILER_RT_ABI fp_t __floatditf(di_int a) {
+
+ const int aWidth = sizeof a * CHAR_BIT;
+
+ // Handle zero as a special case to protect clz
+ if (a == 0)
+ return fromRep(0);
+
+ // All other cases begin by extracting the sign and absolute value of a
+ rep_t sign = 0;
+ du_int aAbs = (du_int)a;
+ if (a < 0) {
+ sign = signBit;
+ aAbs = ~(du_int)a + 1U;
+ }
+
+ // Exponent of (fp_t)a is the width of abs(a).
+ const int exponent = (aWidth - 1) - __builtin_clzll(aAbs);
+ rep_t result;
+
+ // Shift a into the significand field, rounding if it is a right-shift
+ const int shift = significandBits - exponent;
+ result = (rep_t)aAbs << shift ^ implicitBit;
+
+ // Insert the exponent
+ result += (rep_t)(exponent + exponentBias) << significandBits;
+ // Insert the sign bit and return
+ return fromRep(result | sign);
+}
+
+#endif