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#define STACK_ALLOC_PROTECT

#ifdef STACK_ALLOC_PROTECT

// Try to detect stack smashing

#include <assert.h>

#define STACK_ALLOC_PROTECT_SET volatile int stack_check = 0x7fc01234;

#define STACK_ALLOC_PROTECT_CHECK assert(stack_check == 0x7fc01234);

#else

#define STACK_ALLOC_PROTECT_SET

#define STACK_ALLOC_PROTECT_CHECK

#endif

#if defined(MAX_STACK_ALLOC) && MAX_STACK_ALLOC > 0

/*

 * Allocate a buffer on the stack if the size is smaller than MAX_STACK_ALLOC.

 * Stack allocation is much faster than blas_memory_alloc or malloc, particularly

 * when OpenBLAS is used from a multi-threaded application.

 * SIZE must be carefully chosen to be:

 * - as small as possible to maximize the number of stack allocation

 * - large enough to support all architectures and kernel

 * Choosing a SIZE too small will lead to a stack smashing.

 */

#define STACK_ALLOC(SIZE, TYPE, BUFFER)                                        \

  /* make it volatile because some function (ex: dgemv_n.S) */                 \

  /* do not restore all register */                                            \

  volatile int stack_alloc_size = SIZE;                                        \

  if (stack_alloc_size > MAX_STACK_ALLOC / sizeof(TYPE)) stack_alloc_size = 0; \

  STACK_ALLOC_PROTECT_SET                                                      \

  /* Avoid declaring an array of length 0 */                                   \

  TYPE stack_buffer[stack_alloc_size ? stack_alloc_size : 1]                   \

      __attribute__((aligned(0x20)));                                          \

  BUFFER = stack_alloc_size ? stack_buffer : (TYPE *)blas_memory_alloc(1);

#else

  //Original OpenBLAS/GotoBLAS codes.

  #define STACK_ALLOC(SIZE, TYPE, BUFFER) BUFFER = (TYPE *)blas_memory_alloc(1)

#endif

#if defined(MAX_STACK_ALLOC) && MAX_STACK_ALLOC > 0

#define STACK_FREE(BUFFER)    \

  STACK_ALLOC_PROTECT_CHECK   \

  if(!stack_alloc_size)       \

    blas_memory_free(BUFFER);

#else

#define STACK_FREE(BUFFER) blas_memory_free(BUFFER)

#endif