[Mesa-dev] [PATCH 4/5] gallium/util: add helper code for 1D integer range

[Brian Paul]

On 02/27/2013 04:11 PM, Marek Olšák wrote:
> ---
>   src/gallium/auxiliary/util/u_range.h |   91 ++++++++++++++++++++++++++++++++++
>   1 file changed, 91 insertions(+)
>   create mode 100644 src/gallium/auxiliary/util/u_range.h
>
> diff --git a/src/gallium/auxiliary/util/u_range.h b/src/gallium/auxiliary/util/u_range.h
> new file mode 100644
> index 0000000..ae9cc37
> --- /dev/null
> +++ b/src/gallium/auxiliary/util/u_range.h
> @@ -0,0 +1,91 @@
> +/*
> + * Copyright 2013 Marek Olšák<maraeo at gmail.com>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * on the rights to use, copy, modify, merge, publish, 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 the following conditions:
> + *
> + * 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 MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
> + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
> + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
> + * USE OR OTHER DEALINGS IN THE SOFTWARE. */
> +
> +/**
> + * @file
> + * 1D integer range, capable of the union and intersection operations.
> + *
> + * It only maintains a single interval which is extended when the union is
> + * done. This implementation is partially thread-safe (readers are not
> + * protected by a lock).
> + *
> + * @author Marek Olšák
> + */
> +
> +#ifndef U_RANGE_H
> +#define U_RANGE_H
> +
> +#include "os/os_thread.h"

#include "pipe/p_compiler.h" for completeness?


> +
> +struct util_range {
> +	unsigned start; /* inclusive */
> +	unsigned end; /* exclusive */
> +
> +	/* for the range to be consistent with multiple contexts: */
> +	pipe_mutex write_mutex;
> +};

3-space indentation?


> +
> +
> +static INLINE void
> +util_range_set_empty(struct util_range *range)
> +{
> +	range->start = ~0;
> +	range->end = 0;
> +}

Would a util_range_is_empty() function be useful?


> +
> +/* This is like a union of two sets. */
> +static INLINE void
> +util_range_add(struct util_range *range, unsigned start, unsigned end)
> +{
> +	if (start<  range->start || end>  range->end) {
> +		pipe_mutex_lock(range->write_mutex);
> +		if (start<  range->start)
> +			range->start = start;
> +		if (end>  range->end)
> +			range->end = end;

How about:
    range->start = MIN2(range->start, start);
    range->end = MAX2(range->end, end);


> +		pipe_mutex_unlock(range->write_mutex);
> +	}
> +}
> +
> +static INLINE boolean
> +util_ranges_intersect(struct util_range *range, unsigned start, unsigned end)
> +{
> +	return MAX2(start, range->start)<  MIN2(end, range->end);
> +}
> +
> +
> +/* Init/deinit */
> +
> +static INLINE void
> +util_range_init(struct util_range *range)
> +{
> +	pipe_mutex_init(range->write_mutex);
> +	util_range_set_empty(range);
> +}
> +
> +static INLINE void
> +util_range_destroy(struct util_range *range)
> +{
> +	pipe_mutex_destroy(range->write_mutex);
> +}
> +
> +#endif

Reviewed-by: Brian Paul <brianp at vmware.com>