1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  * Copyright (C) IBM Corporation 2014.
4  */
5 
6 #ifndef _RTE_MEMCPY_PPC_64_H_
7 #define _RTE_MEMCPY_PPC_64_H_
8 
9 #include <stdint.h>
10 #include <string.h>
11 
12 #include "rte_altivec.h"
13 #include "rte_common.h"
14 
15 #ifdef __cplusplus
16 extern "C" {
17 #endif
18 
19 #include "generic/rte_memcpy.h"
20 
21 #if (GCC_VERSION >= 90000 && GCC_VERSION < 90400)
22 #pragma GCC diagnostic push
23 #pragma GCC diagnostic ignored "-Warray-bounds"
24 #endif
25 
26 static inline void
rte_mov16(uint8_t * dst,const uint8_t * src)27 rte_mov16(uint8_t *dst, const uint8_t *src)
28 {
29 	vec_vsx_st(vec_vsx_ld(0, src), 0, dst);
30 }
31 
32 static inline void
rte_mov32(uint8_t * dst,const uint8_t * src)33 rte_mov32(uint8_t *dst, const uint8_t *src)
34 {
35 	vec_vsx_st(vec_vsx_ld(0, src), 0, dst);
36 	vec_vsx_st(vec_vsx_ld(16, src), 16, dst);
37 }
38 
39 static inline void
rte_mov48(uint8_t * dst,const uint8_t * src)40 rte_mov48(uint8_t *dst, const uint8_t *src)
41 {
42 	vec_vsx_st(vec_vsx_ld(0, src), 0, dst);
43 	vec_vsx_st(vec_vsx_ld(16, src), 16, dst);
44 	vec_vsx_st(vec_vsx_ld(32, src), 32, dst);
45 }
46 
47 static inline void
rte_mov64(uint8_t * dst,const uint8_t * src)48 rte_mov64(uint8_t *dst, const uint8_t *src)
49 {
50 	vec_vsx_st(vec_vsx_ld(0, src), 0, dst);
51 	vec_vsx_st(vec_vsx_ld(16, src), 16, dst);
52 	vec_vsx_st(vec_vsx_ld(32, src), 32, dst);
53 	vec_vsx_st(vec_vsx_ld(48, src), 48, dst);
54 }
55 
56 static inline void
rte_mov128(uint8_t * dst,const uint8_t * src)57 rte_mov128(uint8_t *dst, const uint8_t *src)
58 {
59 	vec_vsx_st(vec_vsx_ld(0, src), 0, dst);
60 	vec_vsx_st(vec_vsx_ld(16, src), 16, dst);
61 	vec_vsx_st(vec_vsx_ld(32, src), 32, dst);
62 	vec_vsx_st(vec_vsx_ld(48, src), 48, dst);
63 	vec_vsx_st(vec_vsx_ld(64, src), 64, dst);
64 	vec_vsx_st(vec_vsx_ld(80, src), 80, dst);
65 	vec_vsx_st(vec_vsx_ld(96, src), 96, dst);
66 	vec_vsx_st(vec_vsx_ld(112, src), 112, dst);
67 }
68 
69 static inline void
rte_mov256(uint8_t * dst,const uint8_t * src)70 rte_mov256(uint8_t *dst, const uint8_t *src)
71 {
72 	rte_mov128(dst, src);
73 	rte_mov128(dst + 128, src + 128);
74 }
75 
76 #define rte_memcpy(dst, src, n)              \
77 	__extension__ ({                     \
78 	(__builtin_constant_p(n)) ?          \
79 	memcpy((dst), (src), (n)) :          \
80 	rte_memcpy_func((dst), (src), (n)); })
81 
82 static inline void *
rte_memcpy_func(void * dst,const void * src,size_t n)83 rte_memcpy_func(void *dst, const void *src, size_t n)
84 {
85 	void *ret = dst;
86 
87 	/* We can't copy < 16 bytes using XMM registers so do it manually. */
88 	if (n < 16) {
89 		if (n & 0x01) {
90 			*(uint8_t *)dst = *(const uint8_t *)src;
91 			dst = (uint8_t *)dst + 1;
92 			src = (const uint8_t *)src + 1;
93 		}
94 		if (n & 0x02) {
95 			*(uint16_t *)dst = *(const uint16_t *)src;
96 			dst = (uint16_t *)dst + 1;
97 			src = (const uint16_t *)src + 1;
98 		}
99 		if (n & 0x04) {
100 			*(uint32_t *)dst = *(const uint32_t *)src;
101 			dst = (uint32_t *)dst + 1;
102 			src = (const uint32_t *)src + 1;
103 		}
104 		if (n & 0x08)
105 			*(uint64_t *)dst = *(const uint64_t *)src;
106 		return ret;
107 	}
108 
109 	/* Special fast cases for <= 128 bytes */
110 	if (n <= 32) {
111 		rte_mov16((uint8_t *)dst, (const uint8_t *)src);
112 		rte_mov16((uint8_t *)dst - 16 + n,
113 			(const uint8_t *)src - 16 + n);
114 		return ret;
115 	}
116 
117 	if (n <= 64) {
118 		rte_mov32((uint8_t *)dst, (const uint8_t *)src);
119 		rte_mov32((uint8_t *)dst - 32 + n,
120 			(const uint8_t *)src - 32 + n);
121 		return ret;
122 	}
123 
124 	if (n <= 128) {
125 		rte_mov64((uint8_t *)dst, (const uint8_t *)src);
126 		rte_mov64((uint8_t *)dst - 64 + n,
127 			(const uint8_t *)src - 64 + n);
128 		return ret;
129 	}
130 
131 	/*
132 	 * For large copies > 128 bytes. This combination of 256, 64 and 16 byte
133 	 * copies was found to be faster than doing 128 and 32 byte copies as
134 	 * well.
135 	 */
136 	for ( ; n >= 256; n -= 256) {
137 		rte_mov256((uint8_t *)dst, (const uint8_t *)src);
138 		dst = (uint8_t *)dst + 256;
139 		src = (const uint8_t *)src + 256;
140 	}
141 
142 	/*
143 	 * We split the remaining bytes (which will be less than 256) into
144 	 * 64byte (2^6) chunks.
145 	 * Using incrementing integers in the case labels of a switch statement
146 	 * encourages the compiler to use a jump table. To get incrementing
147 	 * integers, we shift the 2 relevant bits to the LSB position to first
148 	 * get decrementing integers, and then subtract.
149 	 */
150 	switch (3 - (n >> 6)) {
151 	case 0x00:
152 		rte_mov64((uint8_t *)dst, (const uint8_t *)src);
153 		n -= 64;
154 		dst = (uint8_t *)dst + 64;
155 		src = (const uint8_t *)src + 64;      /* fallthrough */
156 	case 0x01:
157 		rte_mov64((uint8_t *)dst, (const uint8_t *)src);
158 		n -= 64;
159 		dst = (uint8_t *)dst + 64;
160 		src = (const uint8_t *)src + 64;      /* fallthrough */
161 	case 0x02:
162 		rte_mov64((uint8_t *)dst, (const uint8_t *)src);
163 		n -= 64;
164 		dst = (uint8_t *)dst + 64;
165 		src = (const uint8_t *)src + 64;      /* fallthrough */
166 	default:
167 		;
168 	}
169 
170 	/*
171 	 * We split the remaining bytes (which will be less than 64) into
172 	 * 16byte (2^4) chunks, using the same switch structure as above.
173 	 */
174 	switch (3 - (n >> 4)) {
175 	case 0x00:
176 		rte_mov16((uint8_t *)dst, (const uint8_t *)src);
177 		n -= 16;
178 		dst = (uint8_t *)dst + 16;
179 		src = (const uint8_t *)src + 16;      /* fallthrough */
180 	case 0x01:
181 		rte_mov16((uint8_t *)dst, (const uint8_t *)src);
182 		n -= 16;
183 		dst = (uint8_t *)dst + 16;
184 		src = (const uint8_t *)src + 16;      /* fallthrough */
185 	case 0x02:
186 		rte_mov16((uint8_t *)dst, (const uint8_t *)src);
187 		n -= 16;
188 		dst = (uint8_t *)dst + 16;
189 		src = (const uint8_t *)src + 16;      /* fallthrough */
190 	default:
191 		;
192 	}
193 
194 	/* Copy any remaining bytes, without going beyond end of buffers */
195 	if (n != 0)
196 		rte_mov16((uint8_t *)dst - 16 + n,
197 			(const uint8_t *)src - 16 + n);
198 	return ret;
199 }
200 
201 #if (GCC_VERSION >= 90000 && GCC_VERSION < 90400)
202 #pragma GCC diagnostic pop
203 #endif
204 
205 #ifdef __cplusplus
206 }
207 #endif
208 
209 #endif /* _RTE_MEMCPY_PPC_64_H_ */
210