ArmPkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / ArmPkg / Library / CompilerIntrinsicsLib / Arm / ctzsi2.S

#------------------------------------------------------------------------------\r
#\r
# Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>\r
#\r
# SPDX-License-Identifier: BSD-2-Clause-Patent\r
#\r
#------------------------------------------------------------------------------\r
\r
#include <AsmMacroIoLib.h>\r
\r
ASM_FUNC(__ctzsi2)\r
  uxth  r3, r0\r
  cmp  r3, #0\r
  moveq  ip, #16\r
  movne  ip, #0\r
  @ lr needed for prologue\r
  mov  r0, r0, lsr ip\r
  tst  r0, #255\r
  movne  r3, #0\r
  moveq  r3, #8\r
  mov  r0, r0, lsr r3\r
  tst  r0, #15\r
  movne  r1, #0\r
  moveq  r1, #4\r
  add  r3, r3, ip\r
  mov  r0, r0, lsr r1\r
  tst  r0, #3\r
  movne  r2, #0\r
  moveq  r2, #2\r
  add  r3, r3, r1\r
  mov  r0, r0, lsr r2\r
  and  r0, r0, #3\r
  add  r2, r3, r2\r
  eor  r3, r0, #1\r
  mov  r0, r0, lsr #1\r
  ands  r3, r3, #1\r
  mvnne  r3, #0\r
  rsb  r0, r0, #2\r
  and  r0, r3, r0\r
  add  r0, r2, r0\r
  bx  lr\r