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author | 2020-08-10 21:14:10 +0000 | |
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committer | 2020-08-10 21:14:10 +0000 | |
commit | f2119caf99b8ed409235597050ceebdc9102f562 (patch) | |
tree | cfb90cfe994f47cfaf95506823ca0dac2d08b04d /lib/libcompiler_rt/fp_extend_impl.inc | |
parent | Un-hook and re-hook libcompiler_rt. (diff) | |
download | wireguard-openbsd-f2119caf99b8ed409235597050ceebdc9102f562.tar.xz wireguard-openbsd-f2119caf99b8ed409235597050ceebdc9102f562.zip |
Tedu compiler-rt 8.0.1.
Diffstat (limited to 'lib/libcompiler_rt/fp_extend_impl.inc')
-rw-r--r-- | lib/libcompiler_rt/fp_extend_impl.inc | 108 |
1 files changed, 0 insertions, 108 deletions
diff --git a/lib/libcompiler_rt/fp_extend_impl.inc b/lib/libcompiler_rt/fp_extend_impl.inc deleted file mode 100644 index b785cc7687a..00000000000 --- a/lib/libcompiler_rt/fp_extend_impl.inc +++ /dev/null @@ -1,108 +0,0 @@ -//=-lib/fp_extend_impl.inc - low precision -> high precision conversion -*-- -// -// -// 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 a fairly generic conversion from a narrower to a wider -// IEEE-754 floating-point type. The constants and types defined following the -// includes below parameterize the conversion. -// -// It does not support types that don't use the usual IEEE-754 interchange -// formats; specifically, some work would be needed to adapt it to -// (for example) the Intel 80-bit format or PowerPC double-double format. -// -// Note please, however, that this implementation is only intended to support -// *widening* operations; if you need to convert to a *narrower* floating-point -// type (e.g. double -> float), then this routine will not do what you want it -// to. -// -// It also requires that integer types at least as large as both formats -// are available on the target platform; this may pose a problem when trying -// to add support for quad on some 32-bit systems, for example. You also may -// run into trouble finding an appropriate CLZ function for wide source types; -// you will likely need to roll your own on some platforms. -// -// Finally, the following assumptions are made: -// -// 1. floating-point types and integer types have the same endianness on the -// target platform -// -// 2. quiet NaNs, if supported, are indicated by the leading bit of the -// significand field being set -// -//===----------------------------------------------------------------------===// - -#include "fp_extend.h" - -static __inline dst_t __extendXfYf2__(src_t a) { - // Various constants whose values follow from the type parameters. - // Any reasonable optimizer will fold and propagate all of these. - const int srcBits = sizeof(src_t)*CHAR_BIT; - const int srcExpBits = srcBits - srcSigBits - 1; - const int srcInfExp = (1 << srcExpBits) - 1; - const int srcExpBias = srcInfExp >> 1; - - const src_rep_t srcMinNormal = SRC_REP_C(1) << srcSigBits; - const src_rep_t srcInfinity = (src_rep_t)srcInfExp << srcSigBits; - const src_rep_t srcSignMask = SRC_REP_C(1) << (srcSigBits + srcExpBits); - const src_rep_t srcAbsMask = srcSignMask - 1; - const src_rep_t srcQNaN = SRC_REP_C(1) << (srcSigBits - 1); - const src_rep_t srcNaNCode = srcQNaN - 1; - - const int dstBits = sizeof(dst_t)*CHAR_BIT; - const int dstExpBits = dstBits - dstSigBits - 1; - const int dstInfExp = (1 << dstExpBits) - 1; - const int dstExpBias = dstInfExp >> 1; - - const dst_rep_t dstMinNormal = DST_REP_C(1) << dstSigBits; - - // Break a into a sign and representation of the absolute value - const src_rep_t aRep = srcToRep(a); - const src_rep_t aAbs = aRep & srcAbsMask; - const src_rep_t sign = aRep & srcSignMask; - dst_rep_t absResult; - - // If sizeof(src_rep_t) < sizeof(int), the subtraction result is promoted - // to (signed) int. To avoid that, explicitly cast to src_rep_t. - if ((src_rep_t)(aAbs - srcMinNormal) < srcInfinity - srcMinNormal) { - // a is a normal number. - // Extend to the destination type by shifting the significand and - // exponent into the proper position and rebiasing the exponent. - absResult = (dst_rep_t)aAbs << (dstSigBits - srcSigBits); - absResult += (dst_rep_t)(dstExpBias - srcExpBias) << dstSigBits; - } - - else if (aAbs >= srcInfinity) { - // a is NaN or infinity. - // Conjure the result by beginning with infinity, then setting the qNaN - // bit (if needed) and right-aligning the rest of the trailing NaN - // payload field. - absResult = (dst_rep_t)dstInfExp << dstSigBits; - absResult |= (dst_rep_t)(aAbs & srcQNaN) << (dstSigBits - srcSigBits); - absResult |= (dst_rep_t)(aAbs & srcNaNCode) << (dstSigBits - srcSigBits); - } - - else if (aAbs) { - // a is denormal. - // renormalize the significand and clear the leading bit, then insert - // the correct adjusted exponent in the destination type. - const int scale = src_rep_t_clz(aAbs) - src_rep_t_clz(srcMinNormal); - absResult = (dst_rep_t)aAbs << (dstSigBits - srcSigBits + scale); - absResult ^= dstMinNormal; - const int resultExponent = dstExpBias - srcExpBias - scale + 1; - absResult |= (dst_rep_t)resultExponent << dstSigBits; - } - - else { - // a is zero. - absResult = 0; - } - - // Apply the signbit to (dst_t)abs(a). - const dst_rep_t result = absResult | (dst_rep_t)sign << (dstBits - srcBits); - return dstFromRep(result); -} |