diff --git a/MdePkg/Library/BaseLib/BaseLib.inf b/MdePkg/Library/BaseLib/BaseLib.inf index 7aed3dcdf4..e317ed283d 100644 --- a/MdePkg/Library/BaseLib/BaseLib.inf +++ b/MdePkg/Library/BaseLib/BaseLib.inf @@ -195,6 +195,7 @@ Ia32/WriteDr6.asm | INTEL Ia32/WriteDr5.nasm| INTEL Ia32/WriteDr5.asm | INTEL + Ia32/WriteDr4.nasm| INTEL Ia32/WriteDr4.asm | INTEL Ia32/WriteDr3.asm | INTEL Ia32/WriteDr2.asm | INTEL diff --git a/MdePkg/Library/BaseLib/Ia32/WriteDr4.nasm b/MdePkg/Library/BaseLib/Ia32/WriteDr4.nasm new file mode 100644 index 0000000000..a1b143a2e6 --- /dev/null +++ b/MdePkg/Library/BaseLib/Ia32/WriteDr4.nasm @@ -0,0 +1,45 @@ +;------------------------------------------------------------------------------ +; +; Copyright (c) 2006, Intel Corporation. All rights reserved.
+; This program and the accompanying materials +; are licensed and made available under the terms and conditions of the BSD License +; which accompanies this distribution. The full text of the license may be found at +; http://opensource.org/licenses/bsd-license.php. +; +; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +; +; Module Name: +; +; WriteDr4.Asm +; +; Abstract: +; +; AsmWriteDr4 function +; +; Notes: +; +;------------------------------------------------------------------------------ + + SECTION .text + +;------------------------------------------------------------------------------ +; UINTN +; EFIAPI +; AsmWriteDr4 ( +; IN UINTN Value +; ); +;------------------------------------------------------------------------------ +global ASM_PFX(AsmWriteDr4) +ASM_PFX(AsmWriteDr4): + mov eax, [esp + 4] + ; + ; DR4 is alias to DR6 only if DE (in CR4) is cleared. Otherwise, writing to + ; this register will cause a #UD exception. + ; + ; MS assembler doesn't support this instruction since no one would use it + ; under normal circustances. Here opcode is used. + ; + DB 0xf, 0x23, 0xe0 + ret +