src/glsl/nir/nir_vla.h

/**************************************************************************
 *
 * Copyright 2015 VMware, Inc.
 * All Rights Reserved.
 *
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 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
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 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
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 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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#pragma once


#include "c99_alloca.h"


/* Declare a variable length array, with no initialization */
#define NIR_VLA(_type, _name, _length) \
   _type *_name = alloca((_length) * sizeof *_name)


/* Declare a variable length array, and initialize it with the given byte.
 *
 * _length is evaluated twice, so expressions with side-effects must be
 * avoided.
 */
#define NIR_VLA_FILL(_type, _name, _length, _byte) \
   _type *_name = memset(alloca((_length) * sizeof *_name), _byte, (_length) * sizeof *_name)


/* Declare a variable length array, and zero it.
 *
 * Just like NIR_VLA_FILL, _length is evaluated twice, so expressions with
 * side-effects must be avoided.
 */
#define NIR_VLA_ZERO(_type, _name, _length) \
   NIR_VLA_FILL(_type, _name, _length, 0)