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    stirlingboy1426459970 reacted to nickds1 in Easy way to monitor peak stack usage...   
    I needed a way to see how much of my C++ stack was being consumed in my MSP application - the traditional way is to "poison" the stack with a known pattern, and then to see how much of it gets burnt away.
    So I wrote the following - hope folk find it useful:
    The following code allows you to simply do this and to check at any point how much of the pre-allocated stack was consumed during peak usage, i.e. how close your app got to the bottom of the stack, or indeed, whether it over-ran. The TI CCS documentation is completely wrong in the names it gives for the global symbols that define the size and start of the stack - needs to be updated,
    Stick this code (or similar) wherever you want to report on/check stack usage <smallest number of byes left free on the stack since initialisation>/<configured size of the stack>.
    #if defined(STACK_CHECK) std::printf( "Stack: %d/%d\n", stackMinFreeCount(), stackMaxSize() ); #endif and then, in your main code you need to poison the stack as early as possible and then define the reporting routines: // Define STACK_CHECK to include stack usage diagnostics #define STACK_CHECK #if defined(STACK_CHECK) #define STACK_INIT 0xBEEF // Pattern to use to initially poison the stack extern uint16_t _stack; // Start of stack (low address) uint16_t stackMinFreeCount(void); uint16_t stackMaxSize(void); #endif #if defined(__cplusplus) extern "C" { #endif #if defined(__TI_COMPILER_VERSION__) || \ defined(__GNUC__) int _system_pre_init( void ) #elif defined(__IAR_SYSTEMS_ICC__) int __low_level_init( void ) #endif { //... stuff... #if defined(STACK_CHECK) // // Poison the stack, word by word, with a defined pattern // // Note that _system_pre_init is the earliest that we can // do this and that it may not be possible in TI-RTOS // // When we call the __get_SP_register intrinsic (same on IAR & CCS), it will return the address // of the RET address for the caller of this routine. Make sure that we don't trash it!! // register uint16_t *stack = &_stack; // Address of lowest address in .stack section register uint16_t *stack_top = reinterpret_cast<uint16_t *>(__get_SP_register()); do { *stack++ = STACK_INIT; // Poison stack addresses } while (stack < stack_top); // Stop before top of stack to leave RET address #endif return 1; } #if defined(__cplusplus) } #endif #if defined(STACK_CHECK) /** * Check how deep the stack usage has been * * \return \c uint16_t Minimum number of bytes to bottom of stack */ extern uint16_t __STACK_END; // End of data extern uint16_t __STACK_SIZE; // Linker-set size of stack uint16_t stackMinFreeCount(void) { const uint16_t *stack = &_stack; uint16_t freeCount = 0; while (*stack == STACK_INIT && stack++ <= &__STACK_END) { freeCount++; } return freeCount << 1; } /** * Return size of C++ stack * * Set by the linker --stack_size option * * \return \c uint16_t Configued maximum size of the stack in bytes */ uint16_t stackMaxSize(void) { return static_cast<uint16_t>( _symval(&__STACK_SIZE) ); } #endif int main(void) { ... stuff #if defined(STACK_CHECK) std::printf( "Stack: %d/%d\n", stackMinFreeCount(), stackMaxSize() ); #endif ...stuff }  
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