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Remove <swab.h> and swabXX() functions

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GCC generates correct code for __builtin_bswapXX() on all architectures,
including ArmV4. It seems that whatever bug caused this to not work back
in commit 879ea7fce8 ("endian: Replace explicit byte swapping with
compiler builtin") has been fixed now. We can eliminate the swabXX()
functions and simplify the code.

All instances that had been calling these functions directly should have
been using real endianness conversions anyway.

Change-Id: I19713fd009aa5c0e01c4a42e0cf012364d6bed60
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/90438
Reviewed-by: Maximilian Brune <maximilian.brune@9elements.com>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Frans Hendriks <fhendriks@eltan.com>
This commit is contained in:
Julius Werner 2025-12-09 11:34:18 -08:00 • committed by Yu-Ping Wu
commit 8f34fdfab3
9 changed files with 17 additions and 76 deletions
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1
src/include/endian.h
View file

@ -6,7 +6,6 @@
#include <arch/byteorder.h>
#include <stdint.h>
#include <string.h>
#include <swab.h>
/* This include depends on previous ones, do not reorder. */
#include <commonlib/bsd/_endian.h>

55
src/include/swab.h
View file

@ -1,55 +0,0 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/byteorder/swab.h
* Byte-swapping, independently from CPU endianness
* swabXX[ps]?(foo)
*
* Francois-Rene Rideau <fare@tunes.org> 19971205
* separated swab functions from cpu_to_XX,
* to clean up support for bizarre-endian architectures.
*
* See asm-i386/byteorder.h and such for examples of how to provide
* architecture-dependent optimized versions
*
*/
/* casts are necessary for constants, because we never know how for sure
* how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
*/
#ifndef _SWAB_H
#define _SWAB_H
#include <stdint.h>
#if ENV_ARMV4
#define swab16(x) \
((unsigned short)( \
(((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \
(((unsigned short)(x) & (unsigned short)0xff00U) >> 8)))
#define swab32(x) \
((unsigned int)( \
(((unsigned int)(x) & 0x000000ffUL) << 24) | \
(((unsigned int)(x) & 0x0000ff00UL) << 8) | \
(((unsigned int)(x) & 0x00ff0000UL) >> 8) | \
(((unsigned int)(x) & 0xff000000UL) >> 24)))
#define swab64(x) \
((uint64_t)( \
(((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \
(((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
(((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
(((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) << 8) | \
(((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >> 8) | \
(((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
(((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
(((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
#else /* ENV_ARMV4 */
#define swab16(x) ((uint16_t)__builtin_bswap16(x))
#define swab32(x) ((uint32_t)__builtin_bswap32(x))
#define swab64(x) ((uint64_t)__builtin_bswap64(x))
#endif /* !ENV_ARMV4 */
#endif /* _SWAB_H */