MdePkg/Library/BaseLib/X64/SwitchStack.nasm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006 - 2008, 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 ;   SwitchStack.Asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;------------------------------------------------------------------------------
  19
  20     DEFAULT REL
  21     SECTION .text
  22
  23 ;------------------------------------------------------------------------------
  24 ; Routine Description:
  25 ;
  26 ;   Routine for switching stacks with 2 parameters
  27 ;
  28 ; Arguments:
  29 ;
  30 ;   (rcx) EntryPoint    - Entry point with new stack.
  31 ;   (rdx) Context1      - Parameter1 for entry point.
  32 ;   (r8)  Context2      - Parameter2 for entry point.
  33 ;   (r9)  NewStack      - The pointer to new stack.
  34 ;
  35 ; Returns:
  36 ;
  37 ;   None
  38 ;
  39 ;------------------------------------------------------------------------------
  40 global ASM_PFX(InternalSwitchStack)
  41 ASM_PFX(InternalSwitchStack):
  42     mov     rax, rcx
  43     mov     rcx, rdx
  44     mov     rdx, r8
  45     ;
  46     ; Reserve space for register parameters (rcx, rdx, r8 & r9) on the stack,
  47     ; in case the callee wishes to spill them.
  48     ;
  49     lea     rsp, [r9 - 0x20]
  50     call    rax
  51