; $Id: atan2.asm $
;; @file
; IPRT - No-CRT atan2 - AMD64 & X86.
;

;
; Copyright (C) 2022-2023 Oracle and/or its affiliates.
;
; This file is part of VirtualBox base platform packages, as
; available from https://www.virtualbox.org.
;
; This program is free software; you can redistribute it and/or
; modify it under the terms of the GNU General Public License
; as published by the Free Software Foundation, in version 3 of the
; License.
;
; This program is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
; General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, see <https://www.gnu.org/licenses>.
;
; The contents of this file may alternatively be used under the terms
; of the Common Development and Distribution License Version 1.0
; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
; in the VirtualBox distribution, in which case the provisions of the
; CDDL are applicable instead of those of the GPL.
;
; You may elect to license modified versions of this file under the
; terms and conditions of either the GPL or the CDDL or both.
;
; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
;


%include "iprt/asmdefs.mac"

BEGINCODE

;;
; Arctangent (partial).
;
; @returns st(0) / xmm0
; @param    rdY     [rbp + 8] / xmm0
; @param    rdX     [rbp + 8] / xmm0
RT_NOCRT_BEGINPROC atan2
    push    xBP
    mov     xBP, xSP

%ifdef RT_ARCH_AMD64
    sub     xSP, 20h
    movsd   [xSP + 10h], xmm1
    movsd   [xSP], xmm0
    fld     qword [xSP]
    fld     qword [xSP + 10h]
%else
    fld     qword [xBP + xCB*2]
    fld     qword [xBP + xCB*2 + 8]
%endif

    fpatan

%ifdef RT_ARCH_AMD64
    fstp    qword [xSP]
    movsd   xmm0, [xSP]
%endif
    leave
    ret
ENDPROC   RT_NOCRT(atan2)