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	Required to support big-endian processors, with the most notable being the PowerPC architecture. On little-endian architectures, these conversions can be optimized out and have no code impact. Initial patch provided by gmouchard
		
			
				
	
	
		
			81 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * lfs utility functions
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|  *
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|  * Copyright (c) 2017 ARM Limited
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|  *
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|  * Licensed under the Apache License, Version 2.0 (the "License");
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|  * you may not use this file except in compliance with the License.
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|  * You may obtain a copy of the License at
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|  *
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|  *     http://www.apache.org/licenses/LICENSE-2.0
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|  *
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|  * Unless required by applicable law or agreed to in writing, software
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|  * distributed under the License is distributed on an "AS IS" BASIS,
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|  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|  * See the License for the specific language governing permissions and
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|  * limitations under the License.
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|  */
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| #ifndef LFS_UTIL_H
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| #define LFS_UTIL_H
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| 
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| #include <stdlib.h>
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| #include <stdint.h>
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| #include <stdio.h>
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| 
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| 
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| // Builtin functions, these may be replaced by more
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| // efficient implementations in the system
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| static inline uint32_t lfs_max(uint32_t a, uint32_t b) {
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|     return (a > b) ? a : b;
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| }
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| 
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| static inline uint32_t lfs_min(uint32_t a, uint32_t b) {
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|     return (a < b) ? a : b;
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| }
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| 
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| static inline uint32_t lfs_ctz(uint32_t a) {
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|     return __builtin_ctz(a);
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| }
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| 
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| static inline uint32_t lfs_npw2(uint32_t a) {
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|     return 32 - __builtin_clz(a-1);
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| }
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| 
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| static inline uint32_t lfs_popc(uint32_t a) {
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|     return __builtin_popcount(a);
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| }
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| 
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| static inline int lfs_scmp(uint32_t a, uint32_t b) {
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|     return (int)(unsigned)(a - b);
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| }
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| 
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| static inline uint32_t lfs_fromle32(uint32_t a) {
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| #if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
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|     return a;
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| #elif defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
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|     return __builtin_bswap32(a);
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| #else
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|     return (((uint8_t*)&a)[0] <<  0) |
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|            (((uint8_t*)&a)[1] <<  8) |
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|            (((uint8_t*)&a)[2] << 16) |
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|            (((uint8_t*)&a)[3] << 24);
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| #endif
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| }
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| 
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| static inline uint32_t lfs_tole32(uint32_t a) {
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|     return lfs_fromle32(a);
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| }
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| 
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| // CRC-32 with polynomial = 0x04c11db7
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| void lfs_crc(uint32_t *crc, const void *buffer, size_t size);
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| 
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| 
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| // Logging functions, these may be replaced by system-specific
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| // logging functions
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| #define LFS_DEBUG(fmt, ...) printf("lfs debug: " fmt "\n", __VA_ARGS__)
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| #define LFS_WARN(fmt, ...)  printf("lfs warn: " fmt "\n", __VA_ARGS__)
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| #define LFS_ERROR(fmt, ...) printf("lfs error: " fmt "\n", __VA_ARGS__)
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| 
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| 
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| #endif
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