audk/ArmPkg/Library/CompilerIntrinsicsLib/Arm/ctzsi2.S

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# which accompanies this distribution.  The full text of the license may be found at
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\s\s.text
\s\s.align 2
\s\sGCC_ASM_EXPORT(__ctzsi2)
\s\s
ASM_PFX(__ctzsi2):
\s\suxth\s\sr3, r0
\s\scmp\s\sr3, #0
\s\smoveq\s\sip, #16
\s\smovne\s\sip, #0
\s\s@ lr needed for prologue
\s\smov\s\sr0, r0, lsr ip
\s\stst\s\sr0, #255
\s\smovne\s\sr3, #0
\s\smoveq\s\sr3, #8
\s\smov\s\sr0, r0, lsr r3
\s\stst\s\sr0, #15
\s\smovne\s\sr1, #0
\s\smoveq\s\sr1, #4
\s\sadd\s\sr3, r3, ip
\s\smov\s\sr0, r0, lsr r1
\s\stst\s\sr0, #3
\s\smovne\s\sr2, #0
\s\smoveq\s\sr2, #2
\s\sadd\s\sr3, r3, r1
\s\smov\s\sr0, r0, lsr r2
\s\sand\s\sr0, r0, #3
\s\sadd\s\sr2, r3, r2
\s\seor\s\sr3, r0, #1
\s\smov\s\sr0, r0, lsr #1
\s\sands\s\sr3, r3, #1
\s\smvnne\s\sr3, #0
\s\srsb\s\sr0, r0, #2
\s\sand\s\sr0, r3, r0
\s\sadd\s\sr0, r2, r0
\s\sbx\s\slr