MdePkg/Library/BaseLib/Arm/SetJumpLongJump.S

#------------------------------------------------------------------------------
#
# Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
# Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
#------------------------------------------------------------------------------
.text
.p2align 2

GCC_ASM_EXPORT(SetJump)
GCC_ASM_EXPORT(InternalLongJump)

#/**
#  Saves the current CPU context that can be restored with a call to LongJump() and returns 0.#
#
#  Saves the current CPU context in the buffer specified by JumpBuffer and returns 0.  The initial
#  call to SetJump() must always return 0.  Subsequent calls to LongJump() cause a non-zero
#  value to be returned by SetJump().
#
#  If JumpBuffer is NULL, then ASSERT().
#
#  @param  JumpBuffer    A pointer to CPU context buffer.
#
#**/
#
#UINTN
#EFIAPI
#SetJump (
#  IN      BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer  // R0
#  );
#
ASM_PFX(SetJump):
  mov   r3, r13
  stmia r0, {r3-r12,r14}
  mov   r0, #0
  bx    lr

#/**
#  Restores the CPU context that was saved with SetJump().#
#
#  Restores the CPU context from the buffer specified by JumpBuffer.
#  This function never returns to the caller.
#  Instead it resumes execution based on the state of JumpBuffer.
#
#  @param  JumpBuffer    A pointer to CPU context buffer.
#  @param  Value         The value to return when the SetJump() context is restored.
#
#**/
#VOID
#EFIAPI
#InternalLongJump (
#  IN      BASE_LIBRARY_JUMP_BUFFER  *JumpBuffer,  // R0
#  IN      UINTN                     Value         // R1
#  );
#
ASM_PFX(InternalLongJump):
  ldmia  r0, {r3-r12,r14}
  mov    r13, r3
  cmp    r1, #0
  moveq  r1, #1
  mov    r0, r1
  bx     lr

ASM_FUNCTION_REMOVE_IF_UNREFERENCED