ArmPkg/Include/AsmMacroIoLib.h

   1 /** @file
   2   Macros to work around lack of Apple support for LDR register, =expr
   3
   4   Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   5   Copyright (c) 2011-2012, ARM Ltd. All rights reserved.<BR>
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17
  18 #ifndef __MACRO_IO_LIB_H__
  19 #define __MACRO_IO_LIB_H__
  20
  21 #if defined(__APPLE__)
  22
  23 //
  24 //  ldr reg, =expr does not work with current Apple tool chain. So do the work our selves
  25 //
  26
  27 // load _Reg with _Data
  28 #define LoadConstantToReg(_Data, _Reg)  \
  29   ldr  _Reg, [pc, #0]   ;               \
  30   b    1f               ;               \
  31   .long (_Data)         ;               \
  32 1:
  33
  34 #elif defined (__GNUC__)
  35
  36 #define LoadConstantToReg(Data, Reg) \
  37   ldr  Reg, =Data
  38
  39 #else
  40
  41 //
  42 // Use ARM assembly macros, form armasam
  43 //
  44 //  Less magic in the macros if ldr reg, =expr works
  45 //
  46
  47 // load _Reg with _Data
  48
  49
  50 #define LoadConstantToReg(Data, Reg)  LoadConstantToRegMacro Data, Reg
  51
  52 #endif
  53
  54 #endif