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Diffstat (limited to 'newlib/libm/machine/spu/headers/nextafterf4.h')
| -rw-r--r-- | newlib/libm/machine/spu/headers/nextafterf4.h | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/newlib/libm/machine/spu/headers/nextafterf4.h b/newlib/libm/machine/spu/headers/nextafterf4.h new file mode 100644 index 000000000..15a5e3daf --- /dev/null +++ b/newlib/libm/machine/spu/headers/nextafterf4.h @@ -0,0 +1,120 @@ +/* -------------------------------------------------------------- */ +/* (C)Copyright 2006,2007, */ +/* International Business Machines Corporation */ +/* All Rights Reserved. */ +/* */ +/* Redistribution and use in source and binary forms, with or */ +/* without modification, are permitted provided that the */ +/* following conditions are met: */ +/* */ +/* - Redistributions of source code must retain the above copyright*/ +/* notice, this list of conditions and the following disclaimer. */ +/* */ +/* - Redistributions in binary form must reproduce the above */ +/* copyright notice, this list of conditions and the following */ +/* disclaimer in the documentation and/or other materials */ +/* provided with the distribution. */ +/* */ +/* - Neither the name of IBM Corporation nor the names of its */ +/* contributors may be used to endorse or promote products */ +/* derived from this software without specific prior written */ +/* permission. */ +/* Redistributions of source code must retain the above copyright */ +/* notice, this list of conditions and the following disclaimer. */ +/* */ +/* Redistributions in binary form must reproduce the above */ +/* copyright notice, this list of conditions and the following */ +/* disclaimer in the documentation and/or other materials */ +/* provided with the distribution. */ +/* */ +/* Neither the name of IBM Corporation nor the names of its */ +/* contributors may be used to endorse or promote products */ +/* derived from this software without specific prior written */ +/* permission. */ +/* */ +/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND */ +/* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, */ +/* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */ +/* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE */ +/* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR */ +/* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, */ +/* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT */ +/* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; */ +/* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) */ +/* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN */ +/* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR */ +/* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, */ +/* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +/* -------------------------------------------------------------- */ +/* PROLOG END TAG zYx */ +#ifdef __SPU__ +#ifndef _NEXTAFTERF4_H_ +#define _NEXTAFTERF4_H_ 1 + +#include <spu_intrinsics.h> + +/* + * FUNCTION + * vector float _nextafterf4(vector float x, vector float y) + * + * DESCRIPTION + * The nextafterf4 function returns a vector containing the next representable + * floating-point number after the element of x, in the direction of the + * corresponding element y. + * + * Special Cases: + * - Infinity and NaN are not supported in single-precision on SPU. They are treated + * as normal numbers. + * - x != y, and result = 0 is considered an underflow. + * + * + */ + +static __inline vector float _nextafterf4(vector float x, vector float y) +{ + vec_float4 n1ulp = (vec_float4)spu_splats(0x80000001); + vec_float4 zerof = spu_splats(0.0f); + vec_int4 one = spu_splats(1); + vec_uint4 xlt0, xgty, xeqy, xeq0; + vec_int4 xint; + vec_int4 delta, deltap1; + vec_float4 result; + + /* + * The idea here is to treat x as a signed int value, which allows us to + * add or subtact one to/from it to get the next representable value. + */ + + xeq0 = spu_cmpeq(x, zerof); + xlt0 = spu_cmpgt(zerof, x); + xeqy = spu_cmpeq(x, y); + xgty = spu_cmpgt(x, y); + + /* If x = -0.0, set x = 0.0 */ + x = spu_andc(x, (vec_float4)xeq0); + + xint = (vec_int4)x; + + /* Determine value to add to x */ + delta = (vec_int4)spu_xor(xgty, xlt0); + deltap1 = delta + one; + delta = spu_sel(deltap1, delta, (vec_uint4)delta); + + xint = xint + delta; + + /* Fix the case of x = 0, and answer should be -1 ulp */ + result = spu_sel((vec_float4)xint, n1ulp, spu_and((vec_uint4)delta, xeq0)); + + /* + * Special Cases + */ + + /* x = y */ + result = spu_sel(result, y, xeqy); + + return result; + +} + +#endif /* _NEXTAFTERF4_H_ */ +#endif /* __SPU__ */ |