Merge commit '8bc67ec2c0d2b5444d51a1bed1d50f0e10d92717'

* commit '8bc67ec2c0d2b5444d51a1bed1d50f0e10d92717':
  Checkasm: assembly testing and benchmarking tool

Merged-by: Michael Niedermayer <michael@niedermayer.cc>

1 files changed, 115 insertions, 0 deletions

diff --git a/tests/checkasm/checkasm.h b/tests/checkasm/checkasm.h
new file mode 100644
index 0000000000..039aed7984
--- /dev/null
+++ b/tests/checkasm/checkasm.h
@@ -0,0 +1,115 @@
+/*
+ * Assembly testing and benchmarking tool
+ * Copyright (c) 2015 Henrik Gramner
+ * Copyright (c) 2008 Loren Merritt
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef CHECKASM_H
+#define CHECKASM_H
+
+#include <stdint.h>
+#include "config.h"
+#include "libavutil/avstring.h"
+#include "libavutil/lfg.h"
+#include "libavutil/timer.h"
+
+void checkasm_check_h264pred(void);
+
+intptr_t (*checkasm_check_func(intptr_t (*func)(), const char *name, ...))() av_printf_format(2, 3);
+int checkasm_bench_func(void);
+void checkasm_fail_func(const char *msg, ...) av_printf_format(1, 2);
+void checkasm_update_bench(int iterations, uint64_t cycles);
+void checkasm_report(const char *name, ...) av_printf_format(1, 2);
+
+extern AVLFG checkasm_lfg;
+#define rnd() av_lfg_get(&checkasm_lfg)
+
+static av_unused intptr_t (*func_ref)();
+static av_unused intptr_t (*func_new)();
+
+#define BENCH_RUNS 1000 /* Trade-off between accuracy and speed */
+
+/* Decide whether or not the specified function needs to be tested */
+#define check_func(func, ...) ((func_new = (intptr_t (*)())func) &&\
+                              (func_ref = checkasm_check_func(func_new, __VA_ARGS__)))
+
+/* Indicate that the current test has failed */
+#define fail() checkasm_fail_func("%s:%d", av_basename(__FILE__), __LINE__)
+
+/* Print the test outcome */
+#define report(...) checkasm_report("" __VA_ARGS__)
+
+/* Call the reference function */
+#define call_ref(...) func_ref(__VA_ARGS__)
+
+#if ARCH_X86 && HAVE_YASM
+/* Verifies that clobbered callee-saved registers are properly saved and restored */
+intptr_t checkasm_checked_call(intptr_t (*func)(), ...);
+#endif
+
+/* Call the function */
+#if ARCH_X86_64 && HAVE_YASM
+/* Evil hack: detect incorrect assumptions that 32-bit ints are zero-extended to 64-bit.
+ * This is done by clobbering the stack with junk around the stack pointer and calling the
+ * assembly function through x264_checkasm_call with added dummy arguments which forces all
+ * real arguments to be passed on the stack and not in registers. For 32-bit arguments the
+ * upper half of the 64-bit register locations on the stack will now contain junk which will
+ * cause misbehaving functions to either produce incorrect output or segfault. Note that
+ * even though this works extremely well in practice, it's technically not guaranteed
+ * and false negatives is theoretically possible, but there can never be any false positives.
+ */
+void checkasm_stack_clobber(uint64_t clobber, ...);
+#define CLOB (UINT64_C(0xdeadbeefdeadbeef))
+#define call_new(...) (checkasm_stack_clobber(CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,\
+                                              CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB),\
+                      checkasm_checked_call(func_new, 0, 0, 0, 0, 0, __VA_ARGS__))
+#elif ARCH_X86_32 && HAVE_YASM
+#define call_new(...) checkasm_checked_call(func_new, __VA_ARGS__)
+#else
+#define call_new(...) func_new(__VA_ARGS__)
+#endif
+
+/* Benchmark the function */
+#ifdef AV_READ_TIME
+#define bench_new(...)\
+    do {\
+        if (checkasm_bench_func()) {\
+            intptr_t (*tfunc)() = func_new;\
+            uint64_t tsum = 0;\
+            int ti, tcount = 0;\
+            for (ti = 0; ti < BENCH_RUNS; ti++) {\
+                uint64_t t = AV_READ_TIME();\
+                tfunc(__VA_ARGS__);\
+                tfunc(__VA_ARGS__);\
+                tfunc(__VA_ARGS__);\
+                tfunc(__VA_ARGS__);\
+                t = AV_READ_TIME() - t;\
+                if (t*tcount <= tsum*4 && ti > 0) {\
+                    tsum += t;\
+                    tcount++;\
+                }\
+            }\
+            checkasm_update_bench(tcount, tsum);\
+        }\
+    } while (0)
+#else
+#define bench_new(...)
+#endif
+
+#endif