mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-23 03:10:05 +00:00
279 lines
7.8 KiB
ArmAsm
279 lines
7.8 KiB
ArmAsm
.file "modff.s"
|
|
|
|
|
|
// Copyright (c) 2000 - 2003, Intel Corporation
|
|
// All rights reserved.
|
|
//
|
|
// Contributed 2000 by the Intel Numerics Group, Intel Corporation
|
|
//
|
|
// 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
|
|
//==============================================================
|
|
// 02/02/00 Initial version
|
|
// 04/04/00 Improved speed, corrected result for NaN input
|
|
// 12/22/00 Fixed so inexact flag is never set, and invalid is not set for
|
|
// qnans nor for inputs larger than 2^63.
|
|
// 05/20/02 Cleaned up namespace and sf0 syntax
|
|
// 02/10/03 Reordered header: .section, .global, .proc, .align
|
|
//
|
|
// API
|
|
//==============================================================
|
|
// float modff(float x, float *iptr)
|
|
// break a floating point x number into fraction and an exponent
|
|
//
|
|
// input floating point f8, address in r33
|
|
// output floating point f8 (x fraction), and *iptr (x integral part)
|
|
//
|
|
// OVERVIEW
|
|
//==============================================================
|
|
|
|
// NO FRACTIONAL PART: HUGE
|
|
// If
|
|
// for double-extended
|
|
// If the true exponent is greater than or equal 63
|
|
// 1003e ==> 1003e -ffff = 3f = 63(dec)
|
|
// for double
|
|
// If the true exponent is greater than or equal 52
|
|
// 10033 -ffff = 34 = 52(dec)
|
|
// for single
|
|
// If the true exponent is greater than or equal 23
|
|
// 10016 -ffff = 17 = 23(dec)
|
|
// then
|
|
// we are already an integer (p9 true)
|
|
|
|
// NO INTEGER PART: SMALL
|
|
// Is f8 exponent less than register bias (that is, is it
|
|
// less than 1). If it is, get the right sign of
|
|
// zero and store this in iptr.
|
|
|
|
// CALCULATION: NOT HUGE, NOT SMALL
|
|
// To get the integer part
|
|
// Take the floating-point input and truncate
|
|
// then convert this integer to fp Call it MODF_INTEGER_PART
|
|
|
|
// Subtract MODF_INTEGER_PART from MODF_NORM_F8 to get fraction part
|
|
// Then put fraction part in f8
|
|
// put integer part MODF_INTEGER_PART into *iptr
|
|
|
|
// Registers used
|
|
//==============================================================
|
|
|
|
// predicate registers used:
|
|
// p6 - p13
|
|
|
|
// 0xFFFF 0x10016
|
|
// -----------------------+-----------------+-------------
|
|
// SMALL | NORMAL | HUGE
|
|
// p11 --------------->|<----- p12 ----->| <-------------- p9
|
|
// p10 --------------------------------->|
|
|
// p13 --------------------------------------------------->|
|
|
//
|
|
|
|
// floating-point registers used:
|
|
MODF_NORM_F8 = f9
|
|
MODF_FRACTION_PART = f10
|
|
MODF_INTEGER_PART = f11
|
|
MODF_INT_INTEGER_PART = f12
|
|
|
|
|
|
// general registers used
|
|
modf_signexp = r14
|
|
modf_GR_no_frac = r15
|
|
modf_GR_FFFF = r16
|
|
modf_17_ones = r17
|
|
modf_exp = r18
|
|
// r33 = iptr
|
|
|
|
|
|
.section .text
|
|
GLOBAL_LIBM_ENTRY(modff)
|
|
|
|
// Main path is p9, p11, p8 FALSE and p12 TRUE
|
|
|
|
// Assume input is normalized and get signexp
|
|
// Normalize input just in case
|
|
// Form exponent bias
|
|
{ .mfi
|
|
getf.exp modf_signexp = f8
|
|
fnorm.s0 MODF_NORM_F8 = f8
|
|
addl modf_GR_FFFF = 0xffff, r0
|
|
}
|
|
// Get integer part of input
|
|
// Form exponent mask
|
|
{ .mfi
|
|
nop.m 999
|
|
fcvt.fx.trunc.s1 MODF_INT_INTEGER_PART = f8
|
|
mov modf_17_ones = 0x1ffff ;;
|
|
}
|
|
|
|
// Is x nan or inf?
|
|
// qnan snan inf norm unorm 0 -+
|
|
// 1 1 1 0 0 0 11 = 0xe3 NAN_INF
|
|
// Form biased exponent where input only has an integer part
|
|
{ .mfi
|
|
nop.m 999
|
|
fclass.m.unc p6,p13 = f8, 0xe3
|
|
addl modf_GR_no_frac = 0x10016, r0 ;;
|
|
}
|
|
|
|
// Mask to get exponent
|
|
// Is x unnorm?
|
|
// qnan snan inf norm unorm 0 -+
|
|
// 0 0 0 0 1 0 11 = 0x0b UNORM
|
|
// Set p13 to indicate calculation path, else p6 if nan or inf
|
|
{ .mfi
|
|
and modf_exp = modf_17_ones, modf_signexp
|
|
fclass.m.unc p8,p0 = f8, 0x0b
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// p11 <== SMALL, no integer part, fraction is everyting
|
|
// p9 <== HUGE, no fraction part, integer is everything
|
|
// p12 <== NORMAL, fraction part and integer part
|
|
{ .mii
|
|
(p13) cmp.lt.unc p11,p10 = modf_exp, modf_GR_FFFF
|
|
nop.i 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Is x inf? p6 if inf, p7 if nan
|
|
{ .mfb
|
|
(p10) cmp.ge.unc p9,p12 = modf_exp, modf_GR_no_frac
|
|
(p6) fclass.m.unc p6,p7 = f8, 0x23
|
|
(p8) br.cond.spnt MODF_DENORM ;;
|
|
}
|
|
|
|
MODF_COMMON:
|
|
// For HUGE set fraction to signed 0
|
|
{ .mfi
|
|
nop.m 999
|
|
(p9) fmerge.s f8 = f8,f0
|
|
nop.i 999
|
|
}
|
|
// For HUGE set integer part to normalized input
|
|
{ .mfi
|
|
nop.m 999
|
|
(p9) fnorm.s.s0 MODF_INTEGER_PART = MODF_NORM_F8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// For SMALL set fraction to normalized input, integer part to signed 0
|
|
{ .mfi
|
|
nop.m 999
|
|
(p11) fmerge.s MODF_INTEGER_PART = f8,f0
|
|
nop.i 999
|
|
}
|
|
{ .mfi
|
|
nop.m 999
|
|
(p11) fnorm.s.s0 f8 = MODF_NORM_F8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// For NORMAL float the integer part
|
|
{ .mfi
|
|
nop.m 999
|
|
(p12) fcvt.xf MODF_INTEGER_PART = MODF_INT_INTEGER_PART
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// If x inf set integer part to INF, fraction to signed 0
|
|
{ .mfi
|
|
(p6) stfs [r33] = MODF_NORM_F8
|
|
(p6) fmerge.s f8 = f8,f0
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// If x nan set integer and fraction parts to NaN (quietized)
|
|
{ .mfi
|
|
(p7) stfs [r33] = MODF_NORM_F8
|
|
(p7) fmerge.s f8 = MODF_NORM_F8, MODF_NORM_F8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mmi
|
|
(p9) stfs [r33] = MODF_INTEGER_PART
|
|
nop.m 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// For NORMAL compute fraction part
|
|
{ .mfi
|
|
(p11) stfs [r33] = MODF_INTEGER_PART
|
|
(p12) fms.s.s0 f8 = MODF_NORM_F8,f1, MODF_INTEGER_PART
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// For NORMAL test if fraction part is zero; if so append correct sign
|
|
{ .mfi
|
|
nop.m 999
|
|
(p12) fcmp.eq.unc.s0 p7,p0 = MODF_NORM_F8, MODF_INTEGER_PART
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfi
|
|
(p12) stfs [r33] = MODF_INTEGER_PART
|
|
nop.f 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// For NORMAL if fraction part is zero append sign of input
|
|
{ .mfb
|
|
nop.m 999
|
|
(p7) fmerge.s f8 = MODF_NORM_F8, f0
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
MODF_DENORM:
|
|
// If x unorm get signexp from normalized input
|
|
// If x unorm get integer part from normalized input
|
|
{ .mfi
|
|
getf.exp modf_signexp = MODF_NORM_F8
|
|
fcvt.fx.trunc.s1 MODF_INT_INTEGER_PART = MODF_NORM_F8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// If x unorm mask to get exponent
|
|
{ .mmi
|
|
and modf_exp = modf_17_ones, modf_signexp ;;
|
|
cmp.lt.unc p11,p10 = modf_exp, modf_GR_FFFF
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfb
|
|
(p10) cmp.ge.unc p9,p12 = modf_exp, modf_GR_no_frac
|
|
nop.f 999
|
|
br.cond.spnt MODF_COMMON ;;
|
|
}
|
|
|
|
GLOBAL_LIBM_END(modff)
|