FreeRTOS/Demo/Common/Minimal/flop.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
     FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd.
     All rights reserved

     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

     This file is part of the FreeRTOS distribution.

     FreeRTOS is free software; you can redistribute it and/or modify it under
     the terms of the GNU General Public License (version 2) as published by the
     Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception.

     ***************************************************************************
     >>!   NOTE: The modification to the GPL is included to allow you to     !<<
     >>!   distribute a combined work that includes FreeRTOS without being   !<<
     >>!   obliged to provide the source code for proprietary components     !<<
     >>!   outside of the FreeRTOS kernel.                                   !<<
     ***************************************************************************

     FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
     WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
     FOR A PARTICULAR PURPOSE.  Full license text is available on the following
     link: http://www.freertos.org/a00114.html

     ***************************************************************************
      *                                                                       *
      *    FreeRTOS provides completely free yet professionally developed,    *
      *    robust, strictly quality controlled, supported, and cross          *
      *    platform software that is more than just the market leader, it     *
      *    is the industry's de facto standard.                               *
      *                                                                       *
      *    Help yourself get started quickly while simultaneously helping     *
      *    to support the FreeRTOS project by purchasing a FreeRTOS           *
      *    tutorial book, reference manual, or both:                          *
      *    http://www.FreeRTOS.org/Documentation                              *
      *                                                                       *
     ***************************************************************************

     http://www.FreeRTOS.org/FAQHelp.html - Having a problem?  Start by reading
     the FAQ page "My application does not run, what could be wrong?".  Have you
     defined configASSERT()?

     http://www.FreeRTOS.org/support - In return for receiving this top quality
     embedded software for free we request you assist our global community by
     participating in the support forum.

     http://www.FreeRTOS.org/training - Investing in training allows your team to
     be as productive as possible as early as possible.  Now you can receive
     FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
     Ltd, and the world's leading authority on the world's leading RTOS.

     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
     including FreeRTOS+Trace - an indispensable productivity tool, a DOS
     compatible FAT file system, and our tiny thread aware UDP/IP stack.

     http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
     Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

     http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
     Integrity Systems ltd. to sell under the OpenRTOS brand.  Low cost OpenRTOS
     licenses offer ticketed support, indemnification and commercial middleware.

     http://www.SafeRTOS.com - High Integrity Systems also provide a safety
     engineered and independently SIL3 certified version for use in safety and
     mission critical applications that require provable dependability.

     1 tab == 4 spaces!
 */

 /*
  * Creates eight tasks, each of which loops continuously performing a floating
  * point calculation.
  *
  * All the tasks run at the idle priority and never block or yield.  This causes
  * all eight tasks to time slice with the idle task.  Running at the idle
  * priority means that these tasks will get pre-empted any time another task is
  * ready to run or a time slice occurs.  More often than not the pre-emption
  * will occur mid calculation, creating a good test of the schedulers context
  * switch mechanism - a calculation producing an unexpected result could be a
  * symptom of a corruption in the context of a task.
  */

 /* Standard includes. */
 #include <stdlib.h>
 #include <math.h>

 /* Scheduler include files. */
 #include "FreeRTOS.h"
 #include "task.h"

 /* Demo program include files. */
 #include "flop.h"

 #ifndef mathSTACK_SIZE
 	#define mathSTACK_SIZE		configMINIMAL_STACK_SIZE
 #endif

 #define mathNUMBER_OF_TASKS  ( 4 )

 /* Four tasks, each of which performs a different floating point calculation.
 Each of the four is created twice. */
 static portTASK_FUNCTION_PROTO( vCompetingMathTask1, pvParameters );
 static portTASK_FUNCTION_PROTO( vCompetingMathTask2, pvParameters );
 static portTASK_FUNCTION_PROTO( vCompetingMathTask3, pvParameters );
 static portTASK_FUNCTION_PROTO( vCompetingMathTask4, pvParameters );

 /* These variables are used to check that all the tasks are still running.  If a
 task gets a calculation wrong it will stop setting its check variable. */
 static volatile uint16_t usTaskCheck[ mathNUMBER_OF_TASKS ] = { ( uint16_t ) 0 };

 /*-----------------------------------------------------------*/

 void vStartMathTasks( UBaseType_t uxPriority )
 {
 	xTaskCreate( vCompetingMathTask1, "Math1", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 0 ] ), uxPriority, NULL );
 	xTaskCreate( vCompetingMathTask2, "Math2", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 1 ] ), uxPriority, NULL );
 	xTaskCreate( vCompetingMathTask3, "Math3", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 2 ] ), uxPriority, NULL );
 	xTaskCreate( vCompetingMathTask4, "Math4", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 3 ] ), uxPriority, NULL );
 }
 /*-----------------------------------------------------------*/

 static portTASK_FUNCTION( vCompetingMathTask1, pvParameters )
 {
 volatile portDOUBLE d1, d2, d3, d4;
 volatile uint16_t *pusTaskCheckVariable;
 volatile portDOUBLE dAnswer;
 short sError = pdFALSE;

 	/* Some ports require that tasks that use a hardware floating point unit
 	tell the kernel that they require a floating point context before any
 	floating point instructions are executed. */
 	portTASK_USES_FLOATING_POINT();

 	d1 = 123.4567;
 	d2 = 2345.6789;
 	d3 = -918.222;

 	dAnswer = ( d1 + d2 ) * d3;

 	/* The variable this task increments to show it is still running is passed in
 	as the parameter. */
 	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

 	/* Keep performing a calculation and checking the result against a constant. */
 	for(;;)
 	{
 		d1 = 123.4567;
 		d2 = 2345.6789;
 		d3 = -918.222;

 		d4 = ( d1 + d2 ) * d3;

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		/* If the calculation does not match the expected constant, stop the
 		increment of the check variable. */
 		if( fabs( d4 - dAnswer ) > 0.001 )
 		{
 			sError = pdTRUE;
 		}

 		if( sError == pdFALSE )
 		{
 			/* If the calculation has always been correct then set set the check
 			variable.  The check variable will get set to pdFALSE each time
 			xAreMathsTaskStillRunning() is executed. */
 			( *pusTaskCheckVariable ) = pdTRUE;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 	}
 }
 /*-----------------------------------------------------------*/

 static portTASK_FUNCTION( vCompetingMathTask2, pvParameters )
 {
 volatile portDOUBLE d1, d2, d3, d4;
 volatile uint16_t *pusTaskCheckVariable;
 volatile portDOUBLE dAnswer;
 short sError = pdFALSE;

 	/* Some ports require that tasks that use a hardware floating point unit
 	tell the kernel that they require a floating point context before any
 	floating point instructions are executed. */
 	portTASK_USES_FLOATING_POINT();

 	d1 = -389.38;
 	d2 = 32498.2;
 	d3 = -2.0001;

 	dAnswer = ( d1 / d2 ) * d3;


 	/* The variable this task increments to show it is still running is passed in
 	as the parameter. */
 	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

 	/* Keep performing a calculation and checking the result against a constant. */
 	for( ;; )
 	{
 		d1 = -389.38;
 		d2 = 32498.2;
 		d3 = -2.0001;

 		d4 = ( d1 / d2 ) * d3;

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		/* If the calculation does not match the expected constant, stop the
 		increment of the check variable. */
 		if( fabs( d4 - dAnswer ) > 0.001 )
 		{
 			sError = pdTRUE;
 		}

 		if( sError == pdFALSE )
 		{
 			/* If the calculation has always been correct then set set the check
 			variable.  The check variable will get set to pdFALSE each time
 			xAreMathsTaskStillRunning() is executed. */
 			( *pusTaskCheckVariable ) = pdTRUE;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif
 	}
 }
 /*-----------------------------------------------------------*/

 static portTASK_FUNCTION( vCompetingMathTask3, pvParameters )
 {
 volatile portDOUBLE *pdArray, dTotal1, dTotal2, dDifference;
 volatile uint16_t *pusTaskCheckVariable;
 const size_t xArraySize = 10;
 size_t xPosition;
 short sError = pdFALSE;

 	/* Some ports require that tasks that use a hardware floating point unit
 	tell the kernel that they require a floating point context before any
 	floating point instructions are executed. */
 	portTASK_USES_FLOATING_POINT();

 	/* The variable this task increments to show it is still running is passed in
 	as the parameter. */
 	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

 	pdArray = ( portDOUBLE * ) pvPortMalloc( xArraySize * sizeof( portDOUBLE ) );

 	/* Keep filling an array, keeping a running total of the values placed in the
 	array.  Then run through the array adding up all the values.  If the two totals
 	do not match, stop the check variable from incrementing. */
 	for( ;; )
 	{
 		dTotal1 = 0.0;
 		dTotal2 = 0.0;

 		for( xPosition = 0; xPosition < xArraySize; xPosition++ )
 		{
 			pdArray[ xPosition ] = ( portDOUBLE ) xPosition + 5.5;
 			dTotal1 += ( portDOUBLE ) xPosition + 5.5;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		for( xPosition = 0; xPosition < xArraySize; xPosition++ )
 		{
 			dTotal2 += pdArray[ xPosition ];
 		}

 		dDifference = dTotal1 - dTotal2;
 		if( fabs( dDifference ) > 0.001 )
 		{
 			sError = pdTRUE;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		if( sError == pdFALSE )
 		{
 			/* If the calculation has always been correct then set set the check
 			variable.  The check variable will get set to pdFALSE each time
 			xAreMathsTaskStillRunning() is executed. */
 			( *pusTaskCheckVariable ) = pdTRUE;
 		}
 	}
 }
 /*-----------------------------------------------------------*/

 static portTASK_FUNCTION( vCompetingMathTask4, pvParameters )
 {
 volatile portDOUBLE *pdArray, dTotal1, dTotal2, dDifference;
 volatile uint16_t *pusTaskCheckVariable;
 const size_t xArraySize = 10;
 size_t xPosition;
 short sError = pdFALSE;

 	/* Some ports require that tasks that use a hardware floating point unit
 	tell the kernel that they require a floating point context before any
 	floating point instructions are executed. */
 	portTASK_USES_FLOATING_POINT();

 	/* The variable this task increments to show it is still running is passed in
 	as the parameter. */
 	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

 	pdArray = ( portDOUBLE * ) pvPortMalloc( xArraySize * sizeof( portDOUBLE ) );

 	/* Keep filling an array, keeping a running total of the values placed in the
 	array.  Then run through the array adding up all the values.  If the two totals
 	do not match, stop the check variable from incrementing. */
 	for( ;; )
 	{
 		dTotal1 = 0.0;
 		dTotal2 = 0.0;

 		for( xPosition = 0; xPosition < xArraySize; xPosition++ )
 		{
 			pdArray[ xPosition ] = ( portDOUBLE ) xPosition * 12.123;
 			dTotal1 += ( portDOUBLE ) xPosition * 12.123;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		for( xPosition = 0; xPosition < xArraySize; xPosition++ )
 		{
 			dTotal2 += pdArray[ xPosition ];
 		}

 		dDifference = dTotal1 - dTotal2;
 		if( fabs( dDifference ) > 0.001 )
 		{
 			sError = pdTRUE;
 		}

 		#if configUSE_PREEMPTION == 0
 			taskYIELD();
 		#endif

 		if( sError == pdFALSE )
 		{
 			/* If the calculation has always been correct then set set the check
 			variable.  The check variable will get set to pdFALSE each time
 			xAreMathsTaskStillRunning() is executed. */
 			( *pusTaskCheckVariable ) = pdTRUE;
 		}
 	}
 }
 /*-----------------------------------------------------------*/

 /* This is called to check that all the created tasks are still running. */
 BaseType_t xAreMathsTaskStillRunning( void )
 {
 BaseType_t xReturn = pdPASS, xTask;

 	/* Check the maths tasks are still running by ensuring their check variables
 	have been set to pdPASS. */
 	for( xTask = 0; xTask < mathNUMBER_OF_TASKS; xTask++ )
 	{
 		if( usTaskCheck[ xTask ] != pdTRUE )
 		{
 			/* The check has not been set so the associated task has either
 			stalled or detected an error. */
 			xReturn = pdFAIL;
 		}
 		else
 		{
 			/* Reset the variable so it can be checked again the next time this
 			function is executed. */
 			usTaskCheck[ xTask ] = pdFALSE;
 		}
 	}

 	return xReturn;
 }
	/*
	FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd.
	All rights reserved

	VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

	This file is part of the FreeRTOS distribution.

	FreeRTOS is free software; you can redistribute it and/or modify it under
	the terms of the GNU General Public License (version 2) as published by the
	Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception.

	***************************************************************************
	>>! NOTE: The modification to the GPL is included to allow you to !<<
	>>! distribute a combined work that includes FreeRTOS without being !<<
	>>! obliged to provide the source code for proprietary components !<<
	>>! outside of the FreeRTOS kernel. !<<
	***************************************************************************

	FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
	WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
	FOR A PARTICULAR PURPOSE. Full license text is available on the following
	link: http://www.freertos.org/a00114.html

	***************************************************************************
	* *
	* FreeRTOS provides completely free yet professionally developed, *
	* robust, strictly quality controlled, supported, and cross *
	* platform software that is more than just the market leader, it *
	* is the industry's de facto standard. *
	* *
	* Help yourself get started quickly while simultaneously helping *
	* to support the FreeRTOS project by purchasing a FreeRTOS *
	* tutorial book, reference manual, or both: *
	* http://www.FreeRTOS.org/Documentation *
	* *
	***************************************************************************

	http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
	the FAQ page "My application does not run, what could be wrong?". Have you
	defined configASSERT()?

	http://www.FreeRTOS.org/support - In return for receiving this top quality
	embedded software for free we request you assist our global community by
	participating in the support forum.

	http://www.FreeRTOS.org/training - Investing in training allows your team to
	be as productive as possible as early as possible. Now you can receive
	FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
	Ltd, and the world's leading authority on the world's leading RTOS.

	http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
	including FreeRTOS+Trace - an indispensable productivity tool, a DOS
	compatible FAT file system, and our tiny thread aware UDP/IP stack.

	http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
	Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

	http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
	Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
	licenses offer ticketed support, indemnification and commercial middleware.

	http://www.SafeRTOS.com - High Integrity Systems also provide a safety
	engineered and independently SIL3 certified version for use in safety and
	mission critical applications that require provable dependability.

	1 tab == 4 spaces!
	*/

	/*
	* Creates eight tasks, each of which loops continuously performing a floating
	* point calculation.
	*
	* All the tasks run at the idle priority and never block or yield. This causes
	* all eight tasks to time slice with the idle task. Running at the idle
	* priority means that these tasks will get pre-empted any time another task is
	* ready to run or a time slice occurs. More often than not the pre-emption
	* will occur mid calculation, creating a good test of the schedulers context
	* switch mechanism - a calculation producing an unexpected result could be a
	* symptom of a corruption in the context of a task.
	*/

	/* Standard includes. */
	#include <stdlib.h>
	#include <math.h>

	/* Scheduler include files. */
	#include "FreeRTOS.h"
	#include "task.h"

	/* Demo program include files. */
	#include "flop.h"

	#ifndef mathSTACK_SIZE
	#define mathSTACK_SIZE configMINIMAL_STACK_SIZE
	#endif

	#define mathNUMBER_OF_TASKS ( 4 )

	/* Four tasks, each of which performs a different floating point calculation.
	Each of the four is created twice. */
	static portTASK_FUNCTION_PROTO( vCompetingMathTask1, pvParameters );
	static portTASK_FUNCTION_PROTO( vCompetingMathTask2, pvParameters );
	static portTASK_FUNCTION_PROTO( vCompetingMathTask3, pvParameters );
	static portTASK_FUNCTION_PROTO( vCompetingMathTask4, pvParameters );

	/* These variables are used to check that all the tasks are still running. If a
	task gets a calculation wrong it will stop setting its check variable. */
	static volatile uint16_t usTaskCheck[ mathNUMBER_OF_TASKS ] = { ( uint16_t ) 0 };

	/-----------------------------------------------------------/

	void vStartMathTasks( UBaseType_t uxPriority )
	{
	xTaskCreate( vCompetingMathTask1, "Math1", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 0 ] ), uxPriority, NULL );
	xTaskCreate( vCompetingMathTask2, "Math2", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 1 ] ), uxPriority, NULL );
	xTaskCreate( vCompetingMathTask3, "Math3", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 2 ] ), uxPriority, NULL );
	xTaskCreate( vCompetingMathTask4, "Math4", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 3 ] ), uxPriority, NULL );
	}
	/-----------------------------------------------------------/

	static portTASK_FUNCTION( vCompetingMathTask1, pvParameters )
	{
	volatile portDOUBLE d1, d2, d3, d4;
	volatile uint16_t *pusTaskCheckVariable;
	volatile portDOUBLE dAnswer;
	short sError = pdFALSE;

	/* Some ports require that tasks that use a hardware floating point unit
	tell the kernel that they require a floating point context before any
	floating point instructions are executed. */
	portTASK_USES_FLOATING_POINT();

	d1 = 123.4567;
	d2 = 2345.6789;
	d3 = -918.222;

	dAnswer = ( d1 + d2 ) * d3;

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

	/* Keep performing a calculation and checking the result against a constant. */
	for(;;)
	{
	d1 = 123.4567;
	d2 = 2345.6789;
	d3 = -918.222;

	d4 = ( d1 + d2 ) * d3;

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	/* If the calculation does not match the expected constant, stop the
	increment of the check variable. */
	if( fabs( d4 - dAnswer ) > 0.001 )
	{
	sError = pdTRUE;
	}

	if( sError == pdFALSE )
	{
	/* If the calculation has always been correct then set set the check
	variable. The check variable will get set to pdFALSE each time
	xAreMathsTaskStillRunning() is executed. */
	( *pusTaskCheckVariable ) = pdTRUE;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	}
	}
	/-----------------------------------------------------------/

	static portTASK_FUNCTION( vCompetingMathTask2, pvParameters )
	{
	volatile portDOUBLE d1, d2, d3, d4;
	volatile uint16_t *pusTaskCheckVariable;
	volatile portDOUBLE dAnswer;
	short sError = pdFALSE;

	/* Some ports require that tasks that use a hardware floating point unit
	tell the kernel that they require a floating point context before any
	floating point instructions are executed. */
	portTASK_USES_FLOATING_POINT();

	d1 = -389.38;
	d2 = 32498.2;
	d3 = -2.0001;

	dAnswer = ( d1 / d2 ) * d3;


	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

	/* Keep performing a calculation and checking the result against a constant. */
	for( ;; )
	{
	d1 = -389.38;
	d2 = 32498.2;
	d3 = -2.0001;

	d4 = ( d1 / d2 ) * d3;

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	/* If the calculation does not match the expected constant, stop the
	increment of the check variable. */
	if( fabs( d4 - dAnswer ) > 0.001 )
	{
	sError = pdTRUE;
	}

	if( sError == pdFALSE )
	{
	/* If the calculation has always been correct then set set the check
	variable. The check variable will get set to pdFALSE each time
	xAreMathsTaskStillRunning() is executed. */
	( *pusTaskCheckVariable ) = pdTRUE;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif
	}
	}
	/-----------------------------------------------------------/

	static portTASK_FUNCTION( vCompetingMathTask3, pvParameters )
	{
	volatile portDOUBLE *pdArray, dTotal1, dTotal2, dDifference;
	volatile uint16_t *pusTaskCheckVariable;
	const size_t xArraySize = 10;
	size_t xPosition;
	short sError = pdFALSE;

	/* Some ports require that tasks that use a hardware floating point unit
	tell the kernel that they require a floating point context before any
	floating point instructions are executed. */
	portTASK_USES_FLOATING_POINT();

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

	pdArray = ( portDOUBLE * ) pvPortMalloc( xArraySize * sizeof( portDOUBLE ) );

	/* Keep filling an array, keeping a running total of the values placed in the
	array. Then run through the array adding up all the values. If the two totals
	do not match, stop the check variable from incrementing. */
	for( ;; )
	{
	dTotal1 = 0.0;
	dTotal2 = 0.0;

	for( xPosition = 0; xPosition < xArraySize; xPosition++ )
	{
	pdArray[ xPosition ] = ( portDOUBLE ) xPosition + 5.5;
	dTotal1 += ( portDOUBLE ) xPosition + 5.5;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	for( xPosition = 0; xPosition < xArraySize; xPosition++ )
	{
	dTotal2 += pdArray[ xPosition ];
	}

	dDifference = dTotal1 - dTotal2;
	if( fabs( dDifference ) > 0.001 )
	{
	sError = pdTRUE;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	if( sError == pdFALSE )
	{
	/* If the calculation has always been correct then set set the check
	variable. The check variable will get set to pdFALSE each time
	xAreMathsTaskStillRunning() is executed. */
	( *pusTaskCheckVariable ) = pdTRUE;
	}
	}
	}
	/-----------------------------------------------------------/

	static portTASK_FUNCTION( vCompetingMathTask4, pvParameters )
	{
	volatile portDOUBLE *pdArray, dTotal1, dTotal2, dDifference;
	volatile uint16_t *pusTaskCheckVariable;
	const size_t xArraySize = 10;
	size_t xPosition;
	short sError = pdFALSE;

	/* Some ports require that tasks that use a hardware floating point unit
	tell the kernel that they require a floating point context before any
	floating point instructions are executed. */
	portTASK_USES_FLOATING_POINT();

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( uint16_t * ) pvParameters;

	pdArray = ( portDOUBLE * ) pvPortMalloc( xArraySize * sizeof( portDOUBLE ) );

	/* Keep filling an array, keeping a running total of the values placed in the
	array. Then run through the array adding up all the values. If the two totals
	do not match, stop the check variable from incrementing. */
	for( ;; )
	{
	dTotal1 = 0.0;
	dTotal2 = 0.0;

	for( xPosition = 0; xPosition < xArraySize; xPosition++ )
	{
	pdArray[ xPosition ] = ( portDOUBLE ) xPosition * 12.123;
	dTotal1 += ( portDOUBLE ) xPosition * 12.123;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	for( xPosition = 0; xPosition < xArraySize; xPosition++ )
	{
	dTotal2 += pdArray[ xPosition ];
	}

	dDifference = dTotal1 - dTotal2;
	if( fabs( dDifference ) > 0.001 )
	{
	sError = pdTRUE;
	}

	#if configUSE_PREEMPTION == 0
	taskYIELD();
	#endif

	if( sError == pdFALSE )
	{
	/* If the calculation has always been correct then set set the check
	variable. The check variable will get set to pdFALSE each time
	xAreMathsTaskStillRunning() is executed. */
	( *pusTaskCheckVariable ) = pdTRUE;
	}
	}
	}
	/-----------------------------------------------------------/

	/* This is called to check that all the created tasks are still running. */
	BaseType_t xAreMathsTaskStillRunning( void )
	{
	BaseType_t xReturn = pdPASS, xTask;

	/* Check the maths tasks are still running by ensuring their check variables
	have been set to pdPASS. */
	for( xTask = 0; xTask < mathNUMBER_OF_TASKS; xTask++ )
	{
	if( usTaskCheck[ xTask ] != pdTRUE )
	{
	/* The check has not been set so the associated task has either
	stalled or detected an error. */
	xReturn = pdFAIL;
	}
	else
	{
	/* Reset the variable so it can be checked again the next time this
	function is executed. */
	usTaskCheck[ xTask ] = pdFALSE;
	}
	}

	return xReturn;
	}