kolibrios/programs/develop/open watcom/trunk/clib/cgsupp/7u8f386.asm

82 lines
3.4 KiB
NASM
Raw Normal View History

;*****************************************************************************
;*
;* Open Watcom Project
;*
;* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
;*
;* ========================================================================
;*
;* This file contains Original Code and/or Modifications of Original
;* Code as defined in and that are subject to the Sybase Open Watcom
;* Public License version 1.0 (the 'License'). You may not use this file
;* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
;* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
;* provided with the Original Code and Modifications, and is also
;* available at www.sybase.com/developer/opensource.
;*
;* The Original Code and all software distributed under the License are
;* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
;* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
;* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
;* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
;* NON-INFRINGEMENT. Please see the License for the specific language
;* governing rights and limitations under the License.
;*
;* ========================================================================
;*
;* Description: WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
;* DESCRIBE IT HERE!
;*
;*****************************************************************************
include mdef.inc
include struct.inc
.8087
modstart _7u8f386
xdefp __U8FD7
xdefp __U8FS7
;;;;two_to_64 dw 0000h, 0000h, 0000h, 43f0h ; removed by JBS
ULLMXP1:
DB 00H, 00H, 80H, 5FH ; (float)(ULONGLONG_MAX +1)
; (only exponent set)
defpe __U8FS7
push edx ; save unsigned int64 (hi)
push eax ; save unsigned int64 (lo)
fild qword ptr [esp] ; load as int64
test byte ptr 07H[esp],80H ; most significant bit set?
jns L$2 ; no, jump
fadd dword ptr cs:ULLMXP1 ; correct int64 to unsigned int64 as
; as float (because expression is exact
; in powers of 2, so save 4 bytes)
L$2:
pop eax ; correct stack
fstp dword ptr [esp] ; save float and pop coproc stack
pop eax ; return float in eax
ret
endproc __U8FS7
defpe __U8FD7
push edx ; save unsigned int64 (hi)
push eax ; save unsigned int64 (lo)
fild qword ptr [esp] ; load as int64
test byte ptr 07H[esp],80H ; most significant bit set?
jns L$3 ; no, jump
fadd dword ptr cs:ULLMXP1 ; correct int64 to unsigned int64 as
; as float (because expression is exact
; in powers of 2, so save 4 bytes)
L$3:
fstp qword ptr [esp] ; save double and pop coproc stack
pop eax ; return double (lo)
pop edx ; return double (hi)
ret
endproc __U8FD7
endmod
end