ArmPkg/Library/CompilerIntrinsicsLib/Arm/ctzsi2.S

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   3 # Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
   4 #
   5 # This program and the accompanying materials
   6 # are licensed and made available under the terms and conditions of the BSD License
   7 # which accompanies this distribution.  The full text of the license may be found at
   8 # http://opensource.org/licenses/bsd-license.php
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  10 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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  13 #------------------------------------------------------------------------------
  14
  15 \s\s.text
  16 \s\s.align 2
  17 \s\sGCC_ASM_EXPORT(__ctzsi2)
  18 \s\s
  19 ASM_PFX(__ctzsi2):
  20 \s\suxth\s\sr3, r0
  21 \s\scmp\s\sr3, #0
  22 \s\smoveq\s\sip, #16
  23 \s\smovne\s\sip, #0
  24 \s\s@ lr needed for prologue
  25 \s\smov\s\sr0, r0, lsr ip
  26 \s\stst\s\sr0, #255
  27 \s\smovne\s\sr3, #0
  28 \s\smoveq\s\sr3, #8
  29 \s\smov\s\sr0, r0, lsr r3
  30 \s\stst\s\sr0, #15
  31 \s\smovne\s\sr1, #0
  32 \s\smoveq\s\sr1, #4
  33 \s\sadd\s\sr3, r3, ip
  34 \s\smov\s\sr0, r0, lsr r1
  35 \s\stst\s\sr0, #3
  36 \s\smovne\s\sr2, #0
  37 \s\smoveq\s\sr2, #2
  38 \s\sadd\s\sr3, r3, r1
  39 \s\smov\s\sr0, r0, lsr r2
  40 \s\sand\s\sr0, r0, #3
  41 \s\sadd\s\sr2, r3, r2
  42 \s\seor\s\sr3, r0, #1
  43 \s\smov\s\sr0, r0, lsr #1
  44 \s\sands\s\sr3, r3, #1
  45 \s\smvnne\s\sr3, #0
  46 \s\srsb\s\sr0, r0, #2
  47 \s\sand\s\sr0, r3, r0
  48 \s\sadd\s\sr0, r2, r0
  49 \s\sbx\s\slr