1 /*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "../SDL_internal.h"
22
23 #include "SDL_video.h"
24 #include "SDL_blit.h"
25 #include "SDL_blit_copy.h"
26
27
28 #ifdef __SSE__
29 /* This assumes 16-byte aligned src and dst */
30 static SDL_INLINE void
SDL_memcpySSE(Uint8 * dst,const Uint8 * src,int len)31 SDL_memcpySSE(Uint8 * dst, const Uint8 * src, int len)
32 {
33 int i;
34
35 __m128 values[4];
36 for (i = len / 64; i--;) {
37 _mm_prefetch(src, _MM_HINT_NTA);
38 values[0] = *(__m128 *) (src + 0);
39 values[1] = *(__m128 *) (src + 16);
40 values[2] = *(__m128 *) (src + 32);
41 values[3] = *(__m128 *) (src + 48);
42 _mm_stream_ps((float *) (dst + 0), values[0]);
43 _mm_stream_ps((float *) (dst + 16), values[1]);
44 _mm_stream_ps((float *) (dst + 32), values[2]);
45 _mm_stream_ps((float *) (dst + 48), values[3]);
46 src += 64;
47 dst += 64;
48 }
49
50 if (len & 63)
51 SDL_memcpy(dst, src, len & 63);
52 }
53 #endif /* __SSE__ */
54
55 #ifdef __MMX__
56 #ifdef _MSC_VER
57 #pragma warning(disable:4799)
58 #endif
59 static SDL_INLINE void
SDL_memcpyMMX(Uint8 * dst,const Uint8 * src,int len)60 SDL_memcpyMMX(Uint8 * dst, const Uint8 * src, int len)
61 {
62 const int remain = (len & 63);
63 int i;
64
65 __m64* d64 = (__m64*)dst;
66 __m64* s64 = (__m64*)src;
67
68 for(i= len / 64; i--;) {
69 d64[0] = s64[0];
70 d64[1] = s64[1];
71 d64[2] = s64[2];
72 d64[3] = s64[3];
73 d64[4] = s64[4];
74 d64[5] = s64[5];
75 d64[6] = s64[6];
76 d64[7] = s64[7];
77
78 d64 += 8;
79 s64 += 8;
80 }
81
82 if (remain)
83 {
84 const int skip = len - remain;
85 SDL_memcpy(dst + skip, src + skip, remain);
86 }
87 }
88 #endif /* __MMX__ */
89
90 void
SDL_BlitCopy(SDL_BlitInfo * info)91 SDL_BlitCopy(SDL_BlitInfo * info)
92 {
93 SDL_bool overlap;
94 Uint8 *src, *dst;
95 int w, h;
96 int srcskip, dstskip;
97
98 w = info->dst_w * info->dst_fmt->BytesPerPixel;
99 h = info->dst_h;
100 src = info->src;
101 dst = info->dst;
102 srcskip = info->src_pitch;
103 dstskip = info->dst_pitch;
104
105 /* Properly handle overlapping blits */
106 if (src < dst) {
107 overlap = (dst < (src + h*srcskip));
108 } else {
109 overlap = (src < (dst + h*dstskip));
110 }
111 if (overlap) {
112 if ( dst < src ) {
113 while ( h-- ) {
114 SDL_memmove(dst, src, w);
115 src += srcskip;
116 dst += dstskip;
117 }
118 } else {
119 src += ((h-1) * srcskip);
120 dst += ((h-1) * dstskip);
121 while ( h-- ) {
122 SDL_memmove(dst, src, w);
123 src -= srcskip;
124 dst -= dstskip;
125 }
126 }
127 return;
128 }
129
130 #ifdef __SSE__
131 if (SDL_HasSSE() &&
132 !((uintptr_t) src & 15) && !(srcskip & 15) &&
133 !((uintptr_t) dst & 15) && !(dstskip & 15)) {
134 while (h--) {
135 SDL_memcpySSE(dst, src, w);
136 src += srcskip;
137 dst += dstskip;
138 }
139 return;
140 }
141 #endif
142
143 #ifdef __MMX__
144 if (SDL_HasMMX() && !(srcskip & 7) && !(dstskip & 7)) {
145 while (h--) {
146 SDL_memcpyMMX(dst, src, w);
147 src += srcskip;
148 dst += dstskip;
149 }
150 _mm_empty();
151 return;
152 }
153 #endif
154
155 while (h--) {
156 SDL_memcpy(dst, src, w);
157 src += srcskip;
158 dst += dstskip;
159 }
160 }
161
162 /* vi: set ts=4 sw=4 expandtab: */
163