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authorAlexey Samsonov <samsonov@google.com>2014-02-14 09:20:33 +0000
committerAlexey Samsonov <samsonov@google.com>2014-02-14 09:20:33 +0000
commita6b264b51d4fa786d9df659621fc1ffad1fdc5d0 (patch)
tree416fdf341f03ee1f373907f65ce054afc40d7ab1 /compiler-rt/lib/extendsfdf2.c
parent0b28ea9c471308faf04b4b6695c9f016aabea49a (diff)
downloadbcm5719-llvm-a6b264b51d4fa786d9df659621fc1ffad1fdc5d0.tar.gz
bcm5719-llvm-a6b264b51d4fa786d9df659621fc1ffad1fdc5d0.zip
Move original compiler-rt functions (libgcc replacement) to lib/builtins directory
llvm-svn: 201393
Diffstat (limited to 'compiler-rt/lib/extendsfdf2.c')
-rw-r--r--compiler-rt/lib/extendsfdf2.c137
1 files changed, 0 insertions, 137 deletions
diff --git a/compiler-rt/lib/extendsfdf2.c b/compiler-rt/lib/extendsfdf2.c
deleted file mode 100644
index 91fd2b436a3..00000000000
--- a/compiler-rt/lib/extendsfdf2.c
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-//===-- lib/extendsfdf2.c - single -> double 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 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.
-//
-// This routine can be trivially adapted to support conversions from
-// half-precision or to quad-precision. 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 "int_lib.h"
-
-typedef float src_t;
-typedef uint32_t src_rep_t;
-#define SRC_REP_C UINT32_C
-static const int srcSigBits = 23;
-#define src_rep_t_clz __builtin_clz
-
-typedef double dst_t;
-typedef uint64_t dst_rep_t;
-#define DST_REP_C UINT64_C
-static const int dstSigBits = 52;
-
-// End of specialization parameters. Two helper routines for conversion to and
-// from the representation of floating-point data as integer values follow.
-
-static inline src_rep_t srcToRep(src_t x) {
- const union { src_t f; src_rep_t i; } rep = {.f = x};
- return rep.i;
-}
-
-static inline dst_t dstFromRep(dst_rep_t x) {
- const union { dst_t f; dst_rep_t i; } rep = {.i = x};
- return rep.f;
-}
-
-// End helper routines. Conversion implementation follows.
-
-ARM_EABI_FNALIAS(f2d, extendsfdf2)
-
-dst_t __extendsfdf2(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 (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 |= aAbs & srcNaNCode;
- }
-
- 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);
-}
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