mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-25 20:21:07 +00:00
154 lines
4.1 KiB
ArmAsm
154 lines
4.1 KiB
ArmAsm
.file "significand.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 Unwind support added
|
|
// 05/31/00 Fixed bug when x a double-extended denormal
|
|
// 05/20/02 Cleaned up namespace and sf0 syntax
|
|
// 02/10/03 Reordered header: .section, .global, .proc, .align
|
|
//
|
|
// API
|
|
//==============================================================
|
|
// double significand(double x)
|
|
//
|
|
// Overview of operation
|
|
//==============================================================
|
|
// If x = sig * 2**n with 1 <= sig < 2
|
|
// significand returns sig
|
|
//
|
|
// predicate registers used:
|
|
// p6, p7
|
|
//
|
|
// floating-point registers used:
|
|
// f8, f9, f10
|
|
|
|
.section .text
|
|
GLOBAL_LIBM_ENTRY(significand)
|
|
|
|
// qnan snan inf norm unorm 0 -+
|
|
// 1 1 1 0 0 1 11
|
|
|
|
// f10 gets f8(sign) with f1(exp,significand)
|
|
{ .mfi
|
|
nop.m 999
|
|
fmerge.s f10 = f8,f1
|
|
nop.i 999
|
|
}
|
|
{ .mfi
|
|
nop.m 999
|
|
fnorm.s0 f9 = f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Test for denormal input
|
|
{ .mfi
|
|
nop.m 999
|
|
fclass.m.unc p7,p0 = f8, 0x0b
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// p6 = TRUE ==> x is not (nan,inf,0)
|
|
// return sign(f8) exp(f1) significand(f8)
|
|
// else x is (nan,inf,0)
|
|
// return sign(f8) exp(f8) significand(f8), normalized.
|
|
{ .mfi
|
|
nop.m 999
|
|
fclass.m.unc p0,p6 = f8, 0xe7
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mmb
|
|
nop.m 999
|
|
nop.m 999
|
|
(p7) br.cond.spnt SIGNIFICAND_DENORM ;; // Branch if x denormal
|
|
}
|
|
|
|
{ .mfi
|
|
nop.m 999
|
|
(p6) fmerge.se f8 = f10,f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfb
|
|
nop.m 999
|
|
fnorm.d.s0 f8 = f8
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
SIGNIFICAND_DENORM:
|
|
// Here if x denorm
|
|
{ .mfi
|
|
nop.m 999
|
|
fmerge.se f8 = f10,f9
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Check if fnorm(x) still denormal, means x double-extended denormal
|
|
{ .mfi
|
|
nop.m 999
|
|
fclass.m.unc p7,p0 = f9, 0x0b
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// This will be the final result unless x double-extended denormal
|
|
{ .mfi
|
|
nop.m 999
|
|
fnorm.d.s0 f8 = f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// If x double-extended denorm, then significand ok, but must merge in
|
|
// correct signexp
|
|
{ .mfi
|
|
nop.m 999
|
|
(p7) fmerge.se f8 = f10,f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Final normalization if x double-extended denorm
|
|
{ .mfb
|
|
nop.m 999
|
|
(p7) fnorm.d.s0 f8 = f8
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
GLOBAL_LIBM_END(significand)
|