mirror of
https://github.com/ioquake/ioq3.git
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95 lines
No EOL
2.4 KiB
NASM
Executable file
95 lines
No EOL
2.4 KiB
NASM
Executable file
;===========================================================================
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;Copyright (C) 1999-2005 Id Software, Inc.
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;
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;This file is part of Quake III Arena source code.
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;
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;Quake III Arena source code is free software; you can redistribute it
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;and/or modify it under the terms of the GNU General Public License as
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;published by the Free Software Foundation; either version 2 of the License,
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;or (at your option) any later version.
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;
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;Quake III Arena source code is distributed in the hope that it will be
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;useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
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;MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;GNU General Public License for more details.
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;
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;You should have received a copy of the GNU General Public License
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;along with Foobar; if not, write to the Free Software
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;Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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;===========================================================================
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;
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; Sys_SnapVector NASM code (Andrew Henderson)
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; See win32/win_shared.c for the Win32 equivalent
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; This code is provided to ensure that the
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; rounding behavior (and, if necessary, the
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; precision) of DLL and QVM code are identical
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; e.g. for network-visible operations.
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; See ftol.nasm for operations on a single float,
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; as used in compiled VM and DLL code that does
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; not use this system trap.
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;
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segment .data
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fpucw dd 0
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cw037F dd 0x037F ; Rounding to nearest (even).
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segment .text
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; void Sys_SnapVector( float *v )
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global Sys_SnapVector
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Sys_SnapVector:
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push eax
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push ebp
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mov ebp, esp
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fnstcw [fpucw]
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mov eax, dword [ebp + 12]
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fldcw [cw037F]
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fld dword [eax]
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fistp dword [eax]
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fild dword [eax]
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fstp dword [eax]
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fld dword [eax + 4]
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fistp dword [eax + 4]
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fild dword [eax + 4]
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fstp dword [eax + 4]
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fld dword [eax + 8]
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fistp dword [eax + 8]
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fild dword [eax + 8]
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fstp dword [eax + 8]
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fldcw [fpucw]
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pop ebp
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pop eax
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ret
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; void Sys_SnapVectorCW( float *v, unsigned short int cw )
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global Sys_SnapVectorCW
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Sys_SnapVector_cw:
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push eax
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push ebp
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mov ebp, esp
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fnstcw [fpucw]
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mov eax, dword [ebp + 12]
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fldcw [ebp + 16]
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fld dword [eax]
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fistp dword [eax]
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fild dword [eax]
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fstp dword [eax]
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fld dword [eax + 4]
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fistp dword [eax + 4]
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fild dword [eax + 4]
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fstp dword [eax + 4]
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fld dword [eax + 8]
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fistp dword [eax + 8]
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fild dword [eax + 8]
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fstp dword [eax + 8]
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fldcw [fpucw]
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pop ebp
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pop eax
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ret |