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/*
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* Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies).
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* All rights reserved.
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* This component and the accompanying materials are made available
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* under the terms of "Eclipse Public License v1.0"
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* which accompanies this distribution, and is available
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* at the URL "http://www.eclipse.org/legal/epl-v10.html".
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*
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* Initial Contributors:
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* Nokia Corporation - initial contribution.
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*
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* Contributors:
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*
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* Description: Graphics Extension Library source file
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*
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*/
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@
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@ GfxMultiplyAsm - Multiply a 16:16 fixed point factor into iValue.
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@
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@ This function multiplies a 16:16 fixed point factor into iValue using
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@ an ARM 64 bit multiply instruction. This is much faster than using the
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@ Symbian TInt64 class. Note that iValue MUST be the first data member of
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@ this class.
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@
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@ r0 = Pointer to iValue (First data item in TFixPt class).
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@ r1 = Second factor to multiply.
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.align 2
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.globl GfxMultiplyAsm__6TFixPti
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.thumb_func
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.code 16
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GfxMultiplyAsm__6TFixPti:
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add r2, pc, #4 @ Switch from Thumb to ARM execution.
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bx r2
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nop
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.align 2
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.code 32
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ldr r2, [r0] @ r2 = *this, r1 = aVal.iValue.
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smull r3, r2, r1, r2 @ r2:r3 = iValue * aVal.iValue.
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mov r2, r2, lsl #16
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orr r2, r2, r3, lsr #16 @ Extract middle 32 bits from 64 bit product.
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str r2, [r0] @ Store into iValue.
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bx lr
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