arm-trusted-firmware/include/lib/utils.h
David Cunado 9edac0479d Resolve build errors flagged by GCC 6.2
With GCC 6.2 compiler, more C undefined behaviour is being flagged as
warnings, which result in build errors in ARM TF build.

The specific issue that this patch resolves is the use of (1 << 31),
which is predominantly used in case statements, where 1 is represented
as a signed int. When shifted to msb the behaviour is undefined.

The resolution is to specify 1 as an unsigned int using a convenience
macro ULL(). A duplicate macro MAKE_ULL() is replaced.

Fixes ARM-software/tf-issues#438

Change-Id: I08e3053bbcf4c022ee2be33a75bd0056da4073e1
Signed-off-by: David Cunado <david.cunado@arm.com>
2017-01-26 13:47:37 +00:00

83 lines
3.1 KiB
C

/*
* Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __UTILS_H__
#define __UTILS_H__
/* Compute the number of elements in the given array */
#define ARRAY_SIZE(a) \
(sizeof(a) / sizeof((a)[0]))
#define IS_POWER_OF_TWO(x) \
(((x) & ((x) - 1)) == 0)
#define SIZE_FROM_LOG2_WORDS(n) (4 << (n))
#define BIT(nr) (1UL << (nr))
/*
* The round_up() macro rounds up a value to the given boundary in a
* type-agnostic yet type-safe manner. The boundary must be a power of two.
* In other words, it computes the smallest multiple of boundary which is
* greater than or equal to value.
*
* round_down() is similar but rounds the value down instead.
*/
#define round_boundary(value, boundary) \
((__typeof__(value))((boundary) - 1))
#define round_up(value, boundary) \
((((value) - 1) | round_boundary(value, boundary)) + 1)
#define round_down(value, boundary) \
((value) & ~round_boundary(value, boundary))
/*
* Evaluates to 1 if (ptr + inc) overflows, 0 otherwise.
* Both arguments must be unsigned pointer values (i.e. uintptr_t).
*/
#define check_uptr_overflow(ptr, inc) \
(((ptr) > UINTPTR_MAX - (inc)) ? 1 : 0)
/*
* For those constants to be shared between C and other sources, apply a 'ull'
* suffix to the argument only in C, to avoid undefined or unintended behaviour.
*
* The GNU assembler and linker do not support the 'ull' suffix (it causes the
* build process to fail) therefore the suffix is omitted when used in linker
* scripts and assembler files.
*/
#if defined(__LINKER__) || defined(__ASSEMBLY__)
# define ULL(_x) (_x)
#else
# define ULL(_x) (_x##ull)
#endif
#endif /* __UTILS_H__ */