MdePkg/Library/BaseLib/Arm/SetJumpLongJump.asm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   4 ; Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   5 ; SPDX-License-Identifier: BSD-2-Clause-Patent
   6 ;
   7 ;------------------------------------------------------------------------------
   8
   9   EXPORT  SetJump
  10   EXPORT  InternalLongJump
  11
  12   AREA  BaseLib, CODE, READONLY
  13
  14 ;/**
  15 ;  Saves the current CPU context that can be restored with a call to LongJump() and returns 0.;
  16 ;
  17 ;  Saves the current CPU context in the buffer specified by JumpBuffer and returns 0.  The initial
  18 ;  call to SetJump() must always return 0.  Subsequent calls to LongJump() cause a non-zero
  19 ;  value to be returned by SetJump().
  20 ;
  21 ;  If JumpBuffer is NULL, then ASSERT().
  22 ;  For IPF CPUs, if JumpBuffer is not aligned on a 16-byte boundary, then ASSERT().
  23 ;
  24 ;  @param  JumpBuffer    A pointer to CPU context buffer.
  25 ;
  26 ;**/
  27 ;
  28 ;UINTN
  29 ;EFIAPI
  30 ;SetJump (
  31 ;  IN      BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer  // R0
  32 ;  )
  33 ;
  34 SetJump
  35   MOV  R3, R13
  36   STM  R0, {R3-R12,R14}
  37   EOR  R0, R0
  38   BX   LR
  39
  40 ;/**
  41 ;  Restores the CPU context that was saved with SetJump().;
  42 ;
  43 ;  Restores the CPU context from the buffer specified by JumpBuffer.
  44 ;  This function never returns to the caller.
  45 ;  Instead is resumes execution based on the state of JumpBuffer.
  46 ;
  47 ;  @param  JumpBuffer    A pointer to CPU context buffer.
  48 ;  @param  Value         The value to return when the SetJump() context is restored.
  49 ;
  50 ;**/
  51 ;VOID
  52 ;EFIAPI
  53 ;InternalLongJump (
  54 ;  IN      BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer,  // R0
  55 ;  IN      UINTN                     Value         // R1
  56 ;  );
  57 ;
  58 InternalLongJump
  59   LDM   R0, {R3-R12,R14}
  60   MOV   R13, R3
  61   MOV   R0, R1
  62   BX    LR
  63
  64   END