34 lines
857 B
ArmAsm
34 lines
857 B
ArmAsm
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! Copyright (C) 2012 by Imagination Technologies Ltd.
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!
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! 64-bit logical shift right routine.
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!
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.text
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.global ___lshrdi3
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.type ___lshrdi3,function
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___lshrdi3:
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MOV D0Re0,D0Ar2
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MOV D1Re0,D1Ar1
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CMP D1Ar3,#0 ! COUNT == 0
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MOVEQ PC,D1RtP ! Yes, return
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MOV D0Ar4,D1Ar3
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SUBS D1Ar3,D1Ar3,#32 ! N = COUNT - 32
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BGE $L30
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!! Shift < 32
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NEG D1Ar3,D1Ar3 ! N = - N
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LSR D0Re0,D0Re0,D0Ar4 ! LO = LO >> COUNT
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LSL D0Ar6,D1Re0,D1Ar3 ! TMP= HI << -(COUNT - 32)
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OR D0Re0,D0Re0,D0Ar6 ! LO = LO | TMP
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SWAP D1Ar3,D0Ar4
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LSR D1Re0,D1Re0,D1Ar3 ! HI = HI >> COUNT
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MOV PC,D1RtP
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$L30:
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!! Shift >= 32
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LSR D0Re0,D1Re0,D1Ar3 ! LO = HI >> N
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MOV D1Re0,#0 ! HI = 0
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MOV PC,D1RtP
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.size ___lshrdi3,.-___lshrdi3
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