FFmpeg
cuda_runtime.h
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1 /*
2  * Minimum CUDA compatibility definitions header
3  *
4  * Copyright (c) 2019 Rodger Combs
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef COMPAT_CUDA_CUDA_RUNTIME_H
24 #define COMPAT_CUDA_CUDA_RUNTIME_H
25 
26 // Common macros
27 #define __global__ __attribute__((global))
28 #define __device__ __attribute__((device))
29 #define __device_builtin__ __attribute__((device_builtin))
30 #define __align__(N) __attribute__((aligned(N)))
31 #define __inline__ __inline__ __attribute__((always_inline))
32 
33 #define max(a, b) ((a) > (b) ? (a) : (b))
34 #define min(a, b) ((a) < (b) ? (a) : (b))
35 #define abs(x) ((x) < 0 ? -(x) : (x))
36 
37 #define atomicAdd(a, b) (__atomic_fetch_add(a, b, __ATOMIC_SEQ_CST))
38 
39 // Basic typedefs
40 typedef __device_builtin__ unsigned long long cudaTextureObject_t;
41 
43 {
44  unsigned char x, y;
46 
48 {
49  unsigned short x, y;
51 
52 typedef struct __device_builtin__ uint3
53 {
54  unsigned int x, y, z;
55 } uint3;
56 
57 typedef struct uint3 dim3;
58 
60 {
61  int x, y;
62 } int2;
63 
64 typedef struct __device_builtin__ __align__(4) uchar4
65 {
66  unsigned char x, y, z, w;
68 
69 typedef struct __device_builtin__ __align__(8) ushort4
70 {
71  unsigned char x, y, z, w;
73 
74 typedef struct __device_builtin__ __align__(16) int4
75 {
76  int x, y, z, w;
77 } int4;
78 
79 // Accessors for special registers
80 #define GETCOMP(reg, comp) \
81  asm("mov.u32 %0, %%" #reg "." #comp ";" : "=r"(tmp)); \
82  ret.comp = tmp;
83 
84 #define GET(name, reg) static inline __device__ uint3 name() {\
85  uint3 ret; \
86  unsigned tmp; \
87  GETCOMP(reg, x) \
88  GETCOMP(reg, y) \
89  GETCOMP(reg, z) \
90  return ret; \
91 }
92 
93 GET(getBlockIdx, ctaid)
94 GET(getBlockDim, ntid)
95 GET(getThreadIdx, tid)
96 
97 // Instead of externs for these registers, we turn access to them into calls into trivial ASM
98 #define blockIdx (getBlockIdx())
99 #define blockDim (getBlockDim())
100 #define threadIdx (getThreadIdx())
101 
102 // Basic initializers (simple macros rather than inline functions)
103 #define make_uchar2(a, b) ((uchar2){.x = a, .y = b})
104 #define make_ushort2(a, b) ((ushort2){.x = a, .y = b})
105 #define make_uchar4(a, b, c, d) ((uchar4){.x = a, .y = b, .z = c, .w = d})
106 #define make_ushort4(a, b, c, d) ((ushort4){.x = a, .y = b, .z = c, .w = d})
107 
108 // Conversions from the tex instruction's 4-register output to various types
109 #define TEX2D(type, ret) static inline __device__ void conv(type* out, unsigned a, unsigned b, unsigned c, unsigned d) {*out = (ret);}
110 
111 TEX2D(unsigned char, a & 0xFF)
112 TEX2D(unsigned short, a & 0xFFFF)
113 TEX2D(uchar2, make_uchar2(a & 0xFF, b & 0xFF))
114 TEX2D(ushort2, make_ushort2(a & 0xFFFF, b & 0xFFFF))
115 TEX2D(uchar4, make_uchar4(a & 0xFF, b & 0xFF, c & 0xFF, d & 0xFF))
116 TEX2D(ushort4, make_ushort4(a & 0xFFFF, b & 0xFFFF, c & 0xFFFF, d & 0xFFFF))
117 
118 // Template calling tex instruction and converting the output to the selected type
119 template <class T>
120 static inline __device__ T tex2D(cudaTextureObject_t texObject, float x, float y)
121 {
122  T ret;
123  unsigned ret1, ret2, ret3, ret4;
124  asm("tex.2d.v4.u32.f32 {%0, %1, %2, %3}, [%4, {%5, %6}];" :
125  "=r"(ret1), "=r"(ret2), "=r"(ret3), "=r"(ret4) :
126  "l"(texObject), "f"(x), "f"(y));
127  conv(&ret, ret1, ret2, ret3, ret4);
128  return ret;
129 }
130 
131 #endif /* COMPAT_CUDA_CUDA_RUNTIME_H */
static int conv(int samples, float **pcm, char *buf, int channels)
Definition: libvorbisdec.c:131
ushort2
Definition: cuda_runtime.h:50
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
uchar2
Definition: cuda_runtime.h:45
#define GET(name, reg)
Definition: cuda_runtime.h:84
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
#define __align__(N)
Definition: cuda_runtime.h:30
#define TEX2D(type, ret)
Definition: cuda_runtime.h:109
#define make_ushort2(a, b)
Definition: cuda_runtime.h:104
int2
Definition: cuda_runtime.h:62
unsigned int z
Definition: cuda_runtime.h:54
ushort4
Definition: cuda_runtime.h:72
__device_builtin__ unsigned long long cudaTextureObject_t
Definition: cuda_runtime.h:40
static __device__ T tex2D(cudaTextureObject_t texObject, float x, float y)
Definition: cuda_runtime.h:120
#define make_uchar4(a, b, c, d)
Definition: cuda_runtime.h:105
#define __device__
Definition: cuda_runtime.h:28
#define b
Definition: input.c:41
#define T(x)
Definition: vp56_arith.h:29
uint8_t w
Definition: llviddspenc.c:38
uchar4
Definition: cuda_runtime.h:67
#define __device_builtin__
Definition: cuda_runtime.h:29
#define make_uchar2(a, b)
Definition: cuda_runtime.h:103
#define make_ushort4(a, b, c, d)
Definition: cuda_runtime.h:106
int4
Definition: cuda_runtime.h:77