2 * Assembly testing and benchmarking tool
3 * Copyright (c) 2015 Henrik Gramner
4 * Copyright (c) 2008 Loren Merritt
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
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
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
28 #include "libavutil/avstring.h"
29 #include "libavutil/lfg.h"
30 #include "libavutil/timer.h"
32 void checkasm_check_h264pred(void);
33 void checkasm_check_h264qpel(void);
35 intptr_t (*checkasm_check_func(intptr_t (*func)(), const char *name, ...))() av_printf_format(2, 3);
36 int checkasm_bench_func(void);
37 void checkasm_fail_func(const char *msg, ...) av_printf_format(1, 2);
38 void checkasm_update_bench(int iterations, uint64_t cycles);
39 void checkasm_report(const char *name, ...) av_printf_format(1, 2);
41 extern AVLFG checkasm_lfg;
42 #define rnd() av_lfg_get(&checkasm_lfg)
44 static av_unused intptr_t (*func_ref)();
45 static av_unused intptr_t (*func_new)();
47 #define BENCH_RUNS 1000 /* Trade-off between accuracy and speed */
49 /* Decide whether or not the specified function needs to be tested */
50 #define check_func(func, ...) ((func_new = (intptr_t (*)())func) &&\
51 (func_ref = checkasm_check_func(func_new, __VA_ARGS__)))
53 /* Indicate that the current test has failed */
54 #define fail() checkasm_fail_func("%s:%d", av_basename(__FILE__), __LINE__)
56 /* Print the test outcome */
57 #define report(...) checkasm_report("" __VA_ARGS__)
59 /* Call the reference function */
60 #define call_ref(...) func_ref(__VA_ARGS__)
62 #if ARCH_X86 && HAVE_YASM
63 /* Verifies that clobbered callee-saved registers are properly saved and restored */
64 intptr_t checkasm_checked_call(intptr_t (*func)(), ...);
67 /* Call the function */
68 #if ARCH_X86_64 && HAVE_YASM
69 /* Evil hack: detect incorrect assumptions that 32-bit ints are zero-extended to 64-bit.
70 * This is done by clobbering the stack with junk around the stack pointer and calling the
71 * assembly function through x264_checkasm_call with added dummy arguments which forces all
72 * real arguments to be passed on the stack and not in registers. For 32-bit arguments the
73 * upper half of the 64-bit register locations on the stack will now contain junk which will
74 * cause misbehaving functions to either produce incorrect output or segfault. Note that
75 * even though this works extremely well in practice, it's technically not guaranteed
76 * and false negatives is theoretically possible, but there can never be any false positives.
78 void checkasm_stack_clobber(uint64_t clobber, ...);
79 #define CLOB (UINT64_C(0xdeadbeefdeadbeef))
80 #define call_new(...) (checkasm_stack_clobber(CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,\
81 CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB),\
82 checkasm_checked_call(func_new, 0, 0, 0, 0, 0, __VA_ARGS__))
83 #elif ARCH_X86_32 && HAVE_YASM
84 #define call_new(...) checkasm_checked_call(func_new, __VA_ARGS__)
86 #define call_new(...) func_new(__VA_ARGS__)
89 /* Benchmark the function */
91 #define bench_new(...)\
93 if (checkasm_bench_func()) {\
94 intptr_t (*tfunc)() = func_new;\
97 for (ti = 0; ti < BENCH_RUNS; ti++) {\
98 uint64_t t = AV_READ_TIME();\
103 t = AV_READ_TIME() - t;\
104 if (t*tcount <= tsum*4 && ti > 0) {\
109 checkasm_update_bench(tcount, tsum);\
113 #define bench_new(...) while(0)