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//===-- lib/fixdfsi.c - Double-precision -> integer conversion ----*- C -*-===// |
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// |
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// The LLVM Compiler Infrastructure |
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// |
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// This file is dual licensed under the MIT and the University of Illinois Open |
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// Source Licenses. See LICENSE.TXT for details. |
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// |
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//===----------------------------------------------------------------------===// |
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// |
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// This file implements float to unsigned integer conversion for the |
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// compiler-rt library. |
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// |
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//===----------------------------------------------------------------------===// |
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#include "fp_lib.h" |
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static __inline fixuint_t __fixuint(fp_t a) { |
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// Break a into sign, exponent, significand |
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const rep_t aRep = toRep(a); |
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const rep_t aAbs = aRep & absMask; |
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const int sign = aRep & signBit ? -1 : 1; |
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const int exponent = (aAbs >> significandBits) - exponentBias; |
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const rep_t significand = (aAbs & significandMask) | implicitBit; |
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// If either the value or the exponent is negative, the result is zero. |
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if (sign == -1 || exponent < 0) |
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return 0; |
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// If the value is too large for the integer type, saturate. |
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if ((unsigned)exponent >= sizeof(fixuint_t) * CHAR_BIT) |
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return ~(fixuint_t)0; |
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// If 0 <= exponent < significandBits, right shift to get the result. |
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// Otherwise, shift left. |
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if (exponent < significandBits) |
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return significand >> (significandBits - exponent); |
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else |
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return (fixuint_t)significand << (exponent - significandBits); |
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} |