diff options
Diffstat (limited to 'contrib/compiler-rt/lib/builtins/fp_fixuint_impl.inc')
-rw-r--r-- | contrib/compiler-rt/lib/builtins/fp_fixuint_impl.inc | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/builtins/fp_fixuint_impl.inc b/contrib/compiler-rt/lib/builtins/fp_fixuint_impl.inc new file mode 100644 index 0000000..d68ccf2 --- /dev/null +++ b/contrib/compiler-rt/lib/builtins/fp_fixuint_impl.inc @@ -0,0 +1,39 @@ +//===-- 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); +} |