SDL  2.0
SDL_blit_copy.c
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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
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
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
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  while (h--) {
113  SDL_memmove(dst, src, w);
114  src += srcskip;
115  dst += dstskip;
116  }
117  return;
118  }
119 
120 #ifdef __SSE__
121  if (SDL_HasSSE() &&
122  !((uintptr_t) src & 15) && !(srcskip & 15) &&
123  !((uintptr_t) dst & 15) && !(dstskip & 15)) {
124  while (h--) {
125  SDL_memcpySSE(dst, src, w);
126  src += srcskip;
127  dst += dstskip;
128  }
129  return;
130  }
131 #endif
132 
133 #ifdef __MMX__
134  if (SDL_HasMMX() && !(srcskip & 7) && !(dstskip & 7)) {
135  while (h--) {
136  SDL_memcpyMMX(dst, src, w);
137  src += srcskip;
138  dst += dstskip;
139  }
140  _mm_empty();
141  return;
142  }
143 #endif
144 
145  while (h--) {
146  SDL_memcpy(dst, src, w);
147  src += srcskip;
148  dst += dstskip;
149  }
150 }
151 
152 /* vi: set ts=4 sw=4 expandtab: */
GLenum GLenum dst
Uint8 BytesPerPixel
Definition: SDL_pixels.h:304
int dst_pitch
Definition: SDL_blit.h:63
GLenum GLsizei len
SDL_bool
Definition: SDL_stdinc.h:126
Uint8 * dst
Definition: SDL_blit.h:61
#define SDL_memcpy
void SDL_BlitCopy(SDL_BlitInfo *info)
Definition: SDL_blit_copy.c:91
uint8_t Uint8
An unsigned 8-bit integer type.
Definition: SDL_stdinc.h:139
GLenum GLsizei GLsizei GLint * values
unsigned int uintptr_t
#define SDL_memmove
#define SDL_HasMMX
Uint8 * src
Definition: SDL_blit.h:57
SDL_PixelFormat * dst_fmt
Definition: SDL_blit.h:66
int src_pitch
Definition: SDL_blit.h:59
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:42
#define SDL_INLINE
Definition: begin_code.h:120
GLubyte GLubyte GLubyte GLubyte w
GLenum src
#define SDL_HasSSE
GLfloat GLfloat GLfloat GLfloat h