src/compiler/nir/nir_vla.h

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  27
  28 #ifndef NIR_VLA_H
  29 #define NIR_VLA_H
  30
  31 #include "c99_alloca.h"
  32
  33
  34 /* Declare a variable length array, with no initialization */
  35 #define NIR_VLA(_type, _name, _length) \
  36    _type *_name = alloca((_length) * sizeof *_name)
  37
  38
  39 /* Declare a variable length array, and initialize it with the given byte.
  40  *
  41  * _length is evaluated twice, so expressions with side-effects must be
  42  * avoided.
  43  */
  44 #define NIR_VLA_FILL(_type, _name, _length, _byte) \
  45    _type *_name = memset(alloca((_length) * sizeof *_name), _byte, (_length) * sizeof *_name)
  46
  47
  48 /* Declare a variable length array, and zero it.
  49  *
  50  * Just like NIR_VLA_FILL, _length is evaluated twice, so expressions with
  51  * side-effects must be avoided.
  52  */
  53 #define NIR_VLA_ZERO(_type, _name, _length) \
  54    NIR_VLA_FILL(_type, _name, _length, 0)
  55
  56 #endif /* NIR_VLA_H */