--- a/kernel/eka/nkern/arm/nklib.cia Tue Aug 31 16:34:26 2010 +0300
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,194 +0,0 @@
-// Copyright (c) 2010-2010 Nokia Corporation and/or its subsidiary(-ies).
-// All rights reserved.
-// This component and the accompanying materials are made available
-// under the terms of the License "Eclipse Public License v1.0"
-// which accompanies this distribution, and is available
-// at the URL "http://www.eclipse.org/legal/epl-v10.html".
-//
-// Initial Contributors:
-// Nokia Corporation - initial contribution.
-//
-// Contributors:
-//
-// Description:
-// e32\nkern\arm\nklib.cia
-//
-//
-
-#include <e32atomics.h>
-#include <nklib.h>
-
-#ifdef __SRATIO_MACHINE_CODED__
-__NAKED__ void SRatio::Set(TUint32 /*aInt*/, TInt /*aDivisorExp*/)
- {
-#ifdef __CPU_ARM_HAS_CLZ
- CLZ( 3,1); // r3=31-MSB(r1), 32 if r1=0
- asm("add r2, r2, r3 "); // r2=shift+aDivisorExp
- asm("movs r1, r1, lsl r3 "); // shift r1 left so bit 31=1
- asm("rsb r2, r2, #0 "); // r2 = -shift-aDivisorExp
- asm("moveq r2, #0 "); // if aInt=0, r2=0
- asm("bicne r2, r2, #0xff000000 "); // else clear iSpare fields
- asm("bicne r2, r2, #0x00ff0000 "); //
-#else
- asm("rsb r2, r2, #0 "); // r2 = -aDivisorExp
- asm("cmp r1, #0x00010000 "); // if aInt top 16 bits clear ...
- asm("movcc r1, r1, lsl #16 "); // ... shift 16 bits left ...
- asm("subcc r2, r2, #16 "); // ... and subtract 16 from iX
- asm("cmp r1, #0x01000000 ");
- asm("movcc r1, r1, lsl #8 ");
- asm("subcc r2, r2, #8 ");
- asm("cmp r1, #0x10000000 ");
- asm("movcc r1, r1, lsl #4 ");
- asm("subcc r2, r2, #4 ");
- asm("cmp r1, #0x40000000 ");
- asm("movcc r1, r1, lsl #2 ");
- asm("subcc r2, r2, #2 ");
- asm("cmp r1, #0x80000000 ");
- asm("subcc r2, r2, #1 ");
- asm("cmp r1, #0 ");
- asm("moveq r2, #0 "); // if aInt=0, r2=0
- asm("bicne r2, r2, #0xff000000 "); // else clear iSpare fields
- asm("bicne r2, r2, #0x00ff0000 "); //
-#endif
- asm("stmia r0, {r1,r2} "); // iM in r1, iX in bottom 16 bits of r2
- __JUMP(, lr);
- }
-
-__NAKED__ TInt SRatio::Reciprocal()
- {
- asm("ldr r1, [r0] "); // r1 = iM
- asm("ldrsh r12, [r0, #4] "); // r12 = iX
- asm("rsbs r2, r1, #0 ");
- asm("beq 0f "); // divide by zero
- asm("add r12, r12, #63 ");
- asm("rsb r12, r12, #0 "); // r12 = -63 - iX
- asm("addvs r12, r12, #1 "); // if iM==0x80000000 r12 = -62 - iX (ratio = 2^(31+iX) so reciprocal = 2^(-31-iX) = 2^(31 + (-62-iX))
- asm("bvs 1f "); // iM=0x80000000
-
- // 2^(32+iX) > r > 2^(31+iX)
- // 2^(-32-iX) < 1/r < 2^(-31-iX)
- // 2^(31+(-63-iX)) < 1/r < 2^(31+(-62-iX))
- asm("mov r2, #0 "); // accumulates result
- asm("mov r3, #0x80000000 "); // 33 bit accumulator in C:R3 initialised to 2^32
- asm("2: ");
- asm("adds r3, r3, r3 ");
- asm("cmpcc r3, r1 ");
- asm("subcs r3, r3, r1 "); // if C=1 or r3>=r1, r3-=r1
- asm("adcs r2, r2, r2 "); // next result bit
- asm("bcc 2b "); // finished when we have 33 bits (when top bit shifted off)
- asm("movs r2, r2, lsr #1 "); // rounding bit into C
- asm("orr r2, r2, #0x80000000 "); // top bit back
- asm("adcs r2, r2, #0 "); // add rounding bit
- asm("movcs r2, #0x80000000 "); // if carry, increment exponent
- asm("addcs r12, r12, #1 ");
-
- asm("1: ");
- asm("cmp r12, #-32768 ");
- asm("blt 9f "); // underflow
- asm("cmp r12, #32768 ");
- asm("bge 8f "); // overflow
- asm("str r2, [r0] "); // iM
- asm("strh r12, [r0, #4] "); // iX
- asm("mov r0, #0 ");
- __JUMP(, lr);
-
- asm("0: ");
- asm("mov r0, #%a0" : : "i" ((TInt)KErrDivideByZero));
- __JUMP(, lr);
-
- asm("8: ");
- asm("mov r0, #%a0" : : "i" ((TInt)KErrOverflow));
- __JUMP(, lr);
-
- asm("9: ");
- asm("mov r0, #%a0" : : "i" ((TInt)KErrUnderflow));
- __JUMP(, lr);
- }
-
-__NAKED__ TInt SRatio::Mult(TUint32& /*aInt32*/)
- {
- asm("ldr r3, [r0] "); // r3 = iM
- asm("mov r12, r0 ");
- asm("ldr r0, [r1] "); // r0 = aInt32
- asm("cmp r3, #0 ");
- asm("cmpne r0, #0 ");
- asm("beq 0f "); // result zero
- asm("umull r2, r3, r0, r3 "); // r3:r2 = aInt32 * iM (lowest value 0x0000000080000000)
- asm("ldrsh r12, [r12, #4] "); // r12 = iX
-#ifdef __CPU_ARM_HAS_CLZ
- CLZ( 0, 3); // r0 = number of leading zeros in r3:r2 (can't be >32)
-#else
- asm("str r12, [sp, #-4]! ");
- asm("movs r12, r3 ");
- asm("mov r0, #0 ");
- asm("cmp r12, #0x00010000 ");
- asm("movcc r12, r12, lsl #16 ");
- asm("addcc r0, r0, #16 ");
- asm("cmp r12, #0x01000000 ");
- asm("movcc r12, r12, lsl #8 ");
- asm("addcc r0, r0, #8 ");
- asm("cmp r12, #0x10000000 ");
- asm("movcc r12, r12, lsl #4 ");
- asm("addcc r0, r0, #4 ");
- asm("cmp r12, #0x40000000 ");
- asm("movcc r12, r12, lsl #2 ");
- asm("addcc r0, r0, #2 ");
- asm("cmp r12, #0 ");
- asm("ldr r12, [sp], #4 "); // r12 = iX
- asm("addgt r0, r0, #1 ");
- asm("moveq r0, #32 "); // r0 = number of leading zeros in r3:r2 (can't be >32)
-#endif
- asm("rsb r0, r0, #63 "); // bit number of most significant bit
- asm("add r0, r0, r12 "); // bit number of most significant bit after exponent shift
- asm("cmp r0, #32 ");
- asm("bge 8f "); // overflow
- asm("cmp r0, #-1 ");
- asm("blt 9f "); // underflow
- asm("adds r12, r12, #32 "); // shift needed to get result into top 32 bits (>0 left, <0 right)
- asm("beq 1f "); // no shift
- asm("blt 2f "); // right shift
- asm("rsb r0, r12, #32 ");
- asm("mov r3, r3, lsl r12 ");
- asm("orr r3, r3, r2, lsr r0 ");
- asm("mov r2, r2, lsl r12 "); // r3:r2 <<= r12
- asm("b 1f ");
- asm("2: ");
- asm("rsb r12, r12, #0 ");
- asm("rsb r0, r12, #32 ");
- asm("mov r2, r2, lsr r12 ");
- asm("orr r2, r2, r3, lsl r0 ");
- asm("mov r3, r3, lsr r12 "); // r3:r2 >>= r12
- asm("1: ");
- asm("adds r2, r2, r2 "); // rounding
- asm("adcs r3, r3, #0 ");
- asm("bcs 8f "); // overflow
- asm("beq 9f "); // underflow
- asm("mov r0, #0 ");
- asm("str r3, [r1] ");
- __JUMP(, lr);
-
- asm("0: ");
- asm("mov r0, #0 ");
- asm("str r0, [r1] ");
- __JUMP(, lr);
-
- asm("8: ");
- asm("mvn r0, #0 ");
- asm("str r0, [r1] ");
- asm("mov r0, #%a0" : : "i" ((TInt)KErrOverflow));
- __JUMP(, lr);
-
- asm("9: ");
- asm("mov r0, #0 ");
- asm("str r0, [r1] ");
- asm("mov r0, #%a0" : : "i" ((TInt)KErrUnderflow));
- __JUMP(, lr);
- }
-
-//TInt SRatio::Mult(TUint64& aInt64)
-// {
-// }
-
-#endif
-
-