glibc/sysdeps/ia64/fpu/s_roundl.S
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

234 lines
6.9 KiB
ArmAsm

.file "roundl.s"
// Copyright (c) 2000 - 2003, Intel 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.
//
// * The name of Intel Corporation may not 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 INTEL OR ITS
// 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.
//
// Intel Corporation is the author of this code, and requests that all
// problem reports or change requests be submitted to it directly at
// http://www.intel.com/software/products/opensource/libraries/num.htm.
//
// History
//==============================================================
// 10/25/00 Initial version
// 06/14/01 Changed cmp to an equivalent form
// 05/20/02 Cleaned up namespace and sf0 syntax
// 01/20/03 Improved performance and reduced code size
// 04/18/03 Eliminate possible WAW dependency warning
// 09/03/03 Improved performance
//==============================================================
// API
//==============================================================
// long double roundl(long double x)
//==============================================================
// general input registers:
// r14 - r18
rSignexp = r14
rExp = r15
rExpMask = r16
rBigexp = r17
rExpHalf = r18
// floating-point registers:
// f8 - f13
fXtruncInt = f9
fNormX = f10
fHalf = f11
fInc = f12
fRem = f13
// predicate registers used:
// p6 - p10
// Overview of operation
//==============================================================
// long double roundl(long double x)
// Return an integer value (represented as a long double) that is x
// rounded to nearest integer, halfway cases rounded away from
// zero.
// if x>0 result = trunc(x+0.5)
// if x<0 result = trunc(x-0.5)
//
//==============================================================
// double_extended
// if the exponent is > 1003e => 3F(true) = 63(decimal)
// we have a significand of 64 bits 1.63-bits.
// If we multiply by 2^63, we no longer have a fractional part
// So input is an integer value already.
// double
// if the exponent is >= 10033 => 34(true) = 52(decimal)
// 34 + 3ff = 433
// we have a significand of 53 bits 1.52-bits. (implicit 1)
// If we multiply by 2^52, we no longer have a fractional part
// So input is an integer value already.
// single
// if the exponent is > 10016 => 17(true) = 23(decimal)
// we have a significand of 24 bits 1.23-bits. (implicit 1)
// If we multiply by 2^23, we no longer have a fractional part
// So input is an integer value already.
.section .text
GLOBAL_LIBM_ENTRY(roundl)
{ .mfi
getf.exp rSignexp = f8 // Get signexp, recompute if unorm
fcvt.fx.trunc.s1 fXtruncInt = f8 // Convert to int in significand
addl rBigexp = 0x1003e, r0 // Set exponent at which is integer
}
{ .mfi
mov rExpHalf = 0x0FFFE // Form sign and exponent of 0.5
fnorm.s1 fNormX = f8 // Normalize input
mov rExpMask = 0x1FFFF // Form exponent mask
}
;;
{ .mfi
setf.exp fHalf = rExpHalf // Form 0.5
fclass.m p7,p0 = f8, 0x0b // Test x unorm
nop.i 0
}
;;
{ .mfb
nop.m 0
fclass.m p6,p0 = f8, 0x1e3 // Test x natval, nan, inf
(p7) br.cond.spnt ROUND_UNORM // Branch if x unorm
}
;;
ROUND_COMMON:
// Return here from ROUND_UNORM
{ .mfb
nop.m 0
fcmp.lt.s1 p8,p9 = f8, f0 // Test if x < 0
(p6) br.cond.spnt ROUND_SPECIAL // Exit if x natval, nan, inf
}
;;
{ .mfi
nop.m 0
fcvt.xf f8 = fXtruncInt // Pre-Result if 0.5 <= |x| < 2^63
nop.i 0
}
;;
{ .mfi
and rExp = rSignexp, rExpMask // Get biased exponent
fmerge.s fInc = fNormX, f1 // Form increment if |rem| >= 0.5
nop.i 0
}
;;
{ .mmi
cmp.lt p6,p0 = rExp, rExpHalf // Is |x| < 0.5?
cmp.ge p7,p0 = rExp, rBigexp // Is |x| >= 2^63?
cmp.lt p10,p0 = rExp, rExpHalf // Is |x| < 0.5?
}
;;
// We must correct result if |x| < 0.5, or |x| >= 2^63
.pred.rel "mutex",p6,p7
{ .mfi
nop.m 0
(p6) fmerge.s f8 = fNormX, f0 // If |x| < 0.5, result sgn(x)*0
nop.i 0
}
{ .mfb
(p7) cmp.eq p10,p0 = r0, r0 // Also turn on p10 if |x| >= 2^63
(p7) fma.s0 f8 = fNormX, f1, f0 // If |x| >= 2^63, result x
(p10) br.ret.spnt b0 // Exit |x| < 0.5 or |x| >= 2^63
}
;;
// Here if 0.5 <= |x| < 2^63
{ .mfi
nop.m 0
(p9) fms.s1 fRem = fNormX, f1, f8 // Get remainder = x - trunc(x)
nop.i 0
}
{ .mfi
nop.m 0
(p8) fms.s1 fRem = f8, f1, fNormX // Get remainder = trunc(x) - x
nop.i 0
}
;;
{ .mfi
nop.m 0
fcmp.ge.s1 p9,p0 = fRem, fHalf // Test |rem| >= 0.5
nop.i 0
}
;;
// If x < 0 and remainder <= -0.5, then subtract 1 from result
// If x > 0 and remainder >= +0.5, then add 1 to result
{ .mfb
nop.m 0
(p9) fma.s0 f8 = f8, f1, fInc
br.ret.sptk b0
}
;;
ROUND_SPECIAL:
// Here if x natval, nan, inf
{ .mfb
nop.m 0
fma.s0 f8 = f8, f1, f0
br.ret.sptk b0
}
;;
ROUND_UNORM:
// Here if x unorm
{ .mfi
getf.exp rSignexp = fNormX // Get signexp, recompute if unorm
fcmp.eq.s0 p7,p0 = f8, f0 // Dummy op to set denormal flag
nop.i 0
}
{ .mfb
nop.m 0
fcvt.fx.trunc.s1 fXtruncInt = fNormX // Convert to int in significand
br.cond.sptk ROUND_COMMON // Return to main path
}
;;
GLOBAL_LIBM_END(roundl)
libm_alias_ldouble_other (round, round)