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-rw-r--r--lib/builtins/fp_fixuint_impl.inc39
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diff --git a/lib/builtins/fp_fixuint_impl.inc b/lib/builtins/fp_fixuint_impl.inc
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+//===-- lib/fixdfsi.c - Double-precision -> integer 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 float to unsigned integer conversion for the
+// compiler-rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "fp_lib.h"
+
+static inline fixuint_t __fixuint(fp_t a) {
+ // Break a into sign, exponent, significand
+ const rep_t aRep = toRep(a);
+ const rep_t aAbs = aRep & absMask;
+ const int sign = aRep & signBit ? -1 : 1;
+ const int exponent = (aAbs >> significandBits) - exponentBias;
+ const rep_t significand = (aAbs & significandMask) | implicitBit;
+
+ // If either the value or the exponent is negative, the result is zero.
+ if (sign == -1 || exponent < 0)
+ return 0;
+
+ // If the value is too large for the integer type, saturate.
+ if ((unsigned)exponent > sizeof(fixuint_t) * CHAR_BIT)
+ return ~(fixuint_t)0;
+
+ // If 0 <= exponent < significandBits, right shift to get the result.
+ // Otherwise, shift left.
+ if (exponent < significandBits)
+ return significand >> (significandBits - exponent);
+ else
+ return (fixuint_t)significand << (exponent - significandBits);
+}