Nils O. Selåsdal
85 lines
1.8 KiB
C
85 lines
1.8 KiB
C
#ifndef UC_SATMATH_H_
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#define UC_SATMATH_H_
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#include <stdint.h>
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/** Implementation of saturated operation on uintxx_t.
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*
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* Operations are clamped between 0 and UINTxx_MAX instead of
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* wrapping around.
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*
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* multiplication, subtraction and addition operations are provided.*/
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#define UC_SAT_ADD(a, b, type, max_val)\
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((type)((a) + (b)) >= (a) ? (a) + (b) : (max_val))
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#define UC_SAT_SUB(a, b)\
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((a) >= (b) ? (a) - (b) : 0)
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#define UC_SAT_MULT(a, b, type, max_val)\
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((b) == 0 ? 0 :\
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(a) <= (max_val) / (b) ? (type) (a) * (type) (b) \
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: (max_val))
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static inline uint8_t uc_sat_addu8(uint8_t a, uint8_t b)
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{
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return UC_SAT_ADD(a, b, uint8_t, UINT8_MAX);
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}
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static inline uint8_t uc_sat_subu8(uint8_t a, uint8_t b)
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{
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return UC_SAT_SUB(a, b);
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}
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static inline uint8_t uc_sat_multu8(uint8_t a, uint8_t b)
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{
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return UC_SAT_MULT(a, b, uint8_t, UINT8_MAX);
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}
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static inline uint16_t uc_sat_addu16(uint16_t a, uint16_t b)
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{
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return UC_SAT_ADD(a, b, uint16_t, UINT16_MAX);
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}
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static inline uint16_t uc_sat_subu16(uint16_t a, uint16_t b)
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{
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return UC_SAT_SUB(a, b);
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}
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static inline uint16_t uc_sat_multu16(uint16_t a, uint16_t b)
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{
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return UC_SAT_MULT(a, b, uint16_t, UINT16_MAX);
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}
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static inline uint32_t uc_sat_addu32(uint32_t a, uint32_t b)
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{
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return UC_SAT_ADD(a, b, uint32_t, UINT32_MAX);
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}
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static inline uint32_t uc_sat_subu32(uint32_t a, uint32_t b)
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{
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return UC_SAT_SUB(a, b);
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}
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static inline uint32_t uc_sat_multu32(uint32_t a, uint32_t b)
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{
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return UC_SAT_MULT(a, b, uint32_t, UINT32_MAX);
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}
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static inline uint64_t uc_sat_addu64(uint64_t a, uint64_t b)
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{
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return UC_SAT_ADD(a, b, uint64_t, UINT64_MAX);
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}
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static inline uint64_t uc_sat_subu64(uint64_t a, uint64_t b)
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{
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return UC_SAT_SUB(a, b);
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}
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static inline uint64_t uc_sat_multu64(uint64_t a, uint64_t b)
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{
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return UC_SAT_MULT(a, b, uint64_t, UINT64_MAX);
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}
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#endif
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