1;------------------------------------------------------------------------------ 2; 3; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR> 4; This program and the accompanying materials 5; are licensed and made available under the terms and conditions of the BSD License 6; which accompanies this distribution. The full text of the license may be found at 7; http://opensource.org/licenses/bsd-license.php. 8; 9; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 10; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 11; 12; Module Name: 13; 14; ReadDr4.Asm 15; 16; Abstract: 17; 18; AsmReadDr4 function 19; 20; Notes: 21; 22;------------------------------------------------------------------------------ 23 24 .586p 25 .model flat,C 26 .code 27 28;------------------------------------------------------------------------------ 29; UINTN 30; EFIAPI 31; AsmReadDr4 ( 32; VOID 33; ); 34;------------------------------------------------------------------------------ 35AsmReadDr4 PROC 36 ; 37 ; DR4 is alias to DR6 only if DE (in CR4) is cleared. Otherwise, reading 38 ; this register will cause a #UD exception. 39 ; 40 ; MS assembler doesn't support this instruction since no one would use it 41 ; under normal circustances. Here opcode is used. 42 ; 43 DB 0fh, 21h, 0e0h 44 ret 45AsmReadDr4 ENDP 46 47 END 48