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/* lround function. POWER5+, PowerPC32 version.
Copyright (C) 2006-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<>. */
#include <sysdep.h>
#include <math_ldbl_opt.h>
#include <libm-alias-float.h>
#include <libm-alias-double.h>
/* long [r3] lround (float x [fp1])
IEEE 1003.1 lround function. IEEE specifies "round to the nearest
integer value, rounding halfway cases away from zero, regardless of
the current rounding mode." However PowerPC Architecture defines
"round to Nearest" as "Choose the best approximation. In case of a
tie, choose the one that is even (least significant bit o).".
So we pre-round using the V2.02 Floating Round to Integer Nearest
instruction before we use the Floating Convert to Integer Word with
round to zero instruction. */
.machine "power5"
ENTRY (__lround)
stwu r1,-16(r1)
cfi_adjust_cfa_offset (16)
frin fp2,fp1
fctiwz fp3,fp2 /* Convert To Integer Word lround toward 0. */
stfd fp3,8(r1)
nop /* Ensure the following load is in a different dispatch */
nop /* group to avoid pipe stall on POWER4&5. */
lwz r3,8+LOWORD(r1)
addi r1,r1,16
END (__lround)
libm_alias_double (__lround, lround)
strong_alias (__lround, __lroundf)
libm_alias_float (__lround, lround)