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[CRT]
Implement __rt_sdiv as a wrapper around the unsigned divide (now factored out into an inline worker function) svn path=/trunk/; revision=67179
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@ -476,7 +476,7 @@ elseif(ARCH STREQUAL "amd64")
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endif()
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elseif(ARCH STREQUAL "arm")
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list(APPEND LIBCNTPR_SOURCE
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math/arm/__rt_udiv.c
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math/arm/__rt_div.c
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)
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list(APPEND CRT_ASM_SOURCE
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math/arm/floor.s
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@ -484,7 +484,6 @@ elseif(ARCH STREQUAL "arm")
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math/arm/pow.s
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math/arm/__dtou64.s
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math/arm/__u64tod.s
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math/arm/__rt_sdiv.s
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math/arm/__rt_sdiv64.s
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math/arm/__rt_udiv64.s
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)
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@ -135,7 +135,7 @@ elseif(ARCH STREQUAL "amd64")
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math/sin.c)
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elseif(ARCH STREQUAL "arm")
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list(APPEND LIBCNTPR_SOURCE
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math/arm/__rt_udiv.c
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math/arm/__rt_div.c
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)
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list(APPEND LIBCNTPR_ASM_SOURCE
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math/arm/floor.s
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@ -143,7 +143,6 @@ elseif(ARCH STREQUAL "arm")
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math/arm/pow.s
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math/arm/__dtou64.s
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math/arm/__u64tod.s
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math/arm/__rt_sdiv.s
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math/arm/__rt_sdiv64.s
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math/arm/__rt_udiv64.s
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)
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126
reactos/lib/sdk/crt/math/arm/__rt_div.c
Normal file
126
reactos/lib/sdk/crt/math/arm/__rt_div.c
Normal file
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@ -0,0 +1,126 @@
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/*
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* COPYRIGHT: BSD, see COPYING.ARM in the top level directory
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* PROJECT: ReactOS crt library
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* FILE: lib/sdk/crt/math/arm/__rt_udiv.c
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* PURPOSE: Implementation of __rt_udiv
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* PROGRAMMER: Timo Kreuzer
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* REFERENCE: http://research.microsoft.com/en-us/um/redmond/projects/invisible/src/crt/md/arm/_div10.s.htm
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* http://research.microsoft.com/en-us/um/redmond/projects/invisible/src/crt/md/arm/_udiv.c.htm
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*/
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typedef struct _ARM_UDIVRESULT
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{
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unsigned int quotient; /* to be returned in R0 */
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unsigned int modulus; /* to be returned in R1 */
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} ARM_UDIVRESULT;
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__forceinline
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void
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__brkdiv0(void)
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{
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__emit(0xDEF9);
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}
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__forceinline
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void
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__rt_udiv_internal(
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ARM_UDIVRESULT *result,
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unsigned int divisor,
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unsigned int dividend)
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{
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unsigned int shift;
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unsigned int mask;
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unsigned int quotient;
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if (divisor == 0)
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{
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/* Raise divide by zero error */
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__brkdiv0();
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}
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if (divisor > dividend)
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{
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result->quotient = 0;
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result->modulus = divisor;
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return;
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}
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/* Get the difference in count of leading zeros between dividend and divisor */
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shift = _CountLeadingZeros(divisor);
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shift -= _CountLeadingZeros(dividend);
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/* Shift the divisor to the left, so that it's highest bit is the same
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as the highest bit of the dividend */
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divisor <<= shift;
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mask = 1 << shift;
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quotient = 0;
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do
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{
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if (dividend >= divisor)
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{
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quotient |= mask;
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dividend -= divisor;
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}
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divisor >>= 1;
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mask >>= 1;
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}
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while (mask);
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result->quotient = quotient;
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result->modulus = dividend;
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return;
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}
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ARM_UDIVRESULT
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__rt_udiv(
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unsigned int divisor,
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unsigned int dividend)
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{
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ARM_UDIVRESULT result;
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__rt_udiv_internal(&result, divisor, dividend);
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return result;
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}
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typedef struct _ARM_SDIVRESULT
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{
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int quotient; /* to be returned in R0 */
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int modulus; /* to be returned in R1 */
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} ARM_SDIVRESULT;
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ARM_SDIVRESULT
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__rt_sdiv(
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int divisor,
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int dividend)
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{
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ARM_SDIVRESULT result;
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int divisor_sign, dividend_sign;
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dividend_sign = divisor & 0x80000000;
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if (dividend_sign)
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{
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dividend = -dividend;
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}
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divisor_sign = divisor & 0x80000000;
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if (divisor_sign)
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{
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divisor = -divisor;
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}
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__rt_udiv_internal((ARM_UDIVRESULT*)&result, divisor, dividend);
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if (dividend_sign ^ divisor_sign)
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{
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result.quotient = -result.quotient;
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}
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if (dividend_sign)
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{
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result.modulus = -result.modulus;
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}
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return result;
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}
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@ -1,20 +0,0 @@
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/*
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* COPYRIGHT: See COPYING in the top level directory
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* PROJECT: ReactOS system libraries
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* PURPOSE: Implementation of __rt_sdiv
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* PROGRAMMER: Timo Kreuzer (timo.kreuzer@reactos.org)
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*/
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/* INCLUDES ******************************************************************/
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#include <kxarm.h>
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/* CODE **********************************************************************/
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TEXTAREA
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LEAF_ENTRY __rt_sdiv
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LEAF_END __rt_sdiv
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END
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/* EOF */
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@ -1,73 +0,0 @@
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/*
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* COPYRIGHT: BSD, see COPYING.ARM in the top level directory
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* PROJECT: ReactOS crt library
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* FILE: lib/sdk/crt/math/arm/__rt_udiv.c
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* PURPOSE: Implementation of __rt_udiv
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* PROGRAMMER: Timo Kreuzer
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* REFERENCE: http://research.microsoft.com/en-us/um/redmond/projects/invisible/src/crt/md/arm/_div10.s.htm
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* http://research.microsoft.com/en-us/um/redmond/projects/invisible/src/crt/md/arm/_udiv.c.htm
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*/
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typedef struct _ARM_UDIVRESULT
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{
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unsigned int quotient; /* to be returned in R0 */
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unsigned int modulus; /* to be returned in R1 */
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} ARM_UDIVRESULT;
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__forceinline
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void
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__brkdiv0(void)
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{
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__emit(0xDEF9);
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}
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ARM_UDIVRESULT
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__rt_udiv(
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unsigned int divisor,
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unsigned int dividend)
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{
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ARM_UDIVRESULT result;
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unsigned int BitShift;
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unsigned int BitMask;
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unsigned int Quotient;
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if (divisor == 0)
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{
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/* Raise divide by zero error */
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__brkdiv0();
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}
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if (divisor > dividend)
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{
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result.quotient = 0;
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result.modulus = divisor;
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return result;
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}
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/* Get the difference in count of leading zeros between dividend and divisor */
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BitShift = _CountLeadingZeros(divisor);
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BitShift -= _CountLeadingZeros(dividend);
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/* Shift the divisor to the left, so that it's highest bit is the same
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as the highest bit of the dividend */
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divisor <<= BitShift;
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BitMask = 1 << BitShift;
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do
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{
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if (dividend >= divisor)
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{
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Quotient |= BitMask;
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dividend -= divisor;
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}
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divisor >>= 1;
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BitMask >>= 1;
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}
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while (BitMask);
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result.quotient = Quotient;
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result.modulus = dividend;
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return result;
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}
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