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Diffstat (limited to 'contrib/compiler-rt/lib/builtins/fp_fixint_impl.inc')
-rw-r--r-- | contrib/compiler-rt/lib/builtins/fp_fixint_impl.inc | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/builtins/fp_fixint_impl.inc b/contrib/compiler-rt/lib/builtins/fp_fixint_impl.inc new file mode 100644 index 0000000..da70d4d --- /dev/null +++ b/contrib/compiler-rt/lib/builtins/fp_fixint_impl.inc @@ -0,0 +1,41 @@ +//===-- 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 integer conversion for the +// compiler-rt library. +// +//===----------------------------------------------------------------------===// + +#include "fp_lib.h" + +static __inline fixint_t __fixint(fp_t a) { + const fixint_t fixint_max = (fixint_t)((~(fixuint_t)0) / 2); + const fixint_t fixint_min = -fixint_max - 1; + // Break a into sign, exponent, significand + const rep_t aRep = toRep(a); + const rep_t aAbs = aRep & absMask; + const fixint_t sign = aRep & signBit ? -1 : 1; + const int exponent = (aAbs >> significandBits) - exponentBias; + const rep_t significand = (aAbs & significandMask) | implicitBit; + + // If exponent is negative, the result is zero. + if (exponent < 0) + return 0; + + // If the value is too large for the integer type, saturate. + if ((unsigned)exponent >= sizeof(fixint_t) * CHAR_BIT) + return sign == 1 ? fixint_max : fixint_min; + + // If 0 <= exponent < significandBits, right shift to get the result. + // Otherwise, shift left. + if (exponent < significandBits) + return sign * (significand >> (significandBits - exponent)); + else + return sign * ((fixint_t)significand << (exponent - significandBits)); +} |