MdePkg: Replace Opcode with the corresponding instructions.

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / SetJump.nasm

;------------------------------------------------------------------------------\r
;\r
; Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>\r
; SPDX-License-Identifier: BSD-2-Clause-Patent\r
;\r
; Module Name:\r
;\r
;   SetJump.Asm\r
;\r
; Abstract:\r
;\r
;   Implementation of SetJump() on IA-32.\r
;\r
;------------------------------------------------------------------------------\r
\r
%include "Nasm.inc"\r
\r
    SECTION .text\r
\r
extern ASM_PFX(InternalAssertJumpBuffer)\r
extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))\r
\r
;------------------------------------------------------------------------------\r
; UINTN\r
; EFIAPI\r
; SetJump (\r
;   OUT     BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer\r
;   );\r
;------------------------------------------------------------------------------\r
global ASM_PFX(SetJump)\r
ASM_PFX(SetJump):\r
    push    DWORD [esp + 4]\r
    call    ASM_PFX(InternalAssertJumpBuffer)    ; To validate JumpBuffer\r
    pop     ecx\r
    pop     ecx                         ; ecx <- return address\r
    mov     edx, [esp]\r
\r
    xor     eax, eax\r
    mov     [edx + 24], eax        ; save 0 to SSP\r
\r
    mov     eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]\r
    test    eax, eax\r
    jz      CetDone\r
    mov     eax, cr4\r
    bt      eax, 23                ; check if CET is enabled\r
    jnc     CetDone\r
\r
    mov     eax, 1\r
    incsspd eax                    ; to read original SSP\r
    rdsspd  eax\r
    mov     [edx + 0x24], eax      ; save SSP\r
\r
CetDone:\r
\r
    mov     [edx], ebx\r
    mov     [edx + 4], esi\r
    mov     [edx + 8], edi\r
    mov     [edx + 12], ebp\r
    mov     [edx + 16], esp\r
    mov     [edx + 20], ecx             ; eip value to restore in LongJump\r
    xor     eax, eax\r
    jmp     ecx\r
\r